This was a great thread, but the posted decided to remove his post for no good reason, I'm very sorry for this I wish I could have prevented this from happening, but this will never happen again, as I have put into place safety mmeasures to prevent this.

CNCadmin

Great looking project, we’ll be watching with interest.

Gary

Good luck, IJ. :)

Are you going "4 axis" on this unit? By this, I mean a quill Z drive on the spindle as well as the knee drive you have already built? Powered table up would be a nice feature, but perhaps not something that would be used during a single part program.

That table is heavy to lift up and down much, especially if you are doing much in the way of drill cycles. You might find it desirable to attempt to counterweight the table assembly. I would be concerned about wearing out the vertical ways on the back of the apron. The lube system to the vertical ways is sometimes of questionable value, ie., it could be nigh on impossible to prevent metal to metal contact.

Keep em coming bud, looking forward to follow the story.

LOL Ian,

How much cast iron ended up in your eyes?
Sounds like your 700w motors will do the job just fine then.

Good Showing Ian,

You really take pride in your work, it's good to see. Can't wait to see the next stage.

Ian,

That sounds OK since you are using a 25mm Ballscew, however, make sure you are not going to end up with whip in it as the controller you have will be able to spin it a 3700 rpm. It may pay you to talk to lee abount the RPM and maximum overhang when the ballscrew nut is at one end. That is of course if you are wanting to run it at supersonic speed. It is possible to de tune your drive to the speed that your ballscrew is happy with but I don't want you to get disappointed if it is not the speed you want, so , before you cut it too short make your mind up, or if you can, leave the screw a bit longer incase you have to turn an end bearing journal in the future.

Good luck

You beauty!!!

Go Get 'em dude.

Ian,

Overbuilt is good, much better than under built.

I have no problems with you posting pics of our controller.

IJ, I am following this thread closely, and I am interested in what controller you are planning to use for this project. It appears that you are using industry standard BLDC drives that accept ±10vdc. I have a machine very simmilar to this, with motors, drives and an outdated control. The controller is the part that I would like to update. My problem is that all of the software that I have found outputs step and direction. The drives that I have only accept ±10vdc. I realize that Rutex makes a converter board, but I thought that you might have a more elegant solution, or a more sophisticated software. If so, please let me know what you are planning on using.
Thanks-
NEATman

BTW, I like the Kollmorgen Silverline motors that you are using. Brushless DC is definetly the way to go. The only thing to wear out is the ball bearings.

Where did you get the ballscrew for the knee, what work did you have to do to it?

More pics of knee would be helpful for me as I am about to embark in retroing my mill also.

IJ:
What are those drives?
I'm very interested because I have 3 SST-1500-ACX on the shelf waiting for testing.
They look very much like yours, except for the silk screen printing. But I have only 2 motors, one very small and one small, both Technics motors. I'd be happy to hear about how you set up those motors with the drives if they are the same as mine. If you replace the capital letter words in my sig below, you have my email address, as this may not be very interesting to the others.

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Very nice work so far. Always overbuild is my rule. Most parts will be a pain to rebuild later so it's best to get everything 2x as strong as you need it because you never know what the future holds.

Ian, I'm impressed!

Klox

Ian, i've got a mill just like yours. I'm itching to convert it to cnc, however the funds are lacking at this stage. This is why i'm so interested in what you have done & how you have gone about doing the retrofit. At some stage i would be the one asking lots of questions......

Keep well,

Klox

Ian: I think my biggest obstacle would be the electronics side of things (I'm a BIG computor idiot! LOL!).
Maybe i could bribe Kookaburra to come and help me.....

The machining you did looks excellent, so neat!
Keep up your good work!

Klox

Klox,

I'm up for bribes, lol. Maybe I could come over and first of all watch my rugby union team beat yours and then come and help you with the retro, lol. :cheers:

Klox: I think by far the hardest part and the most critical to get correct is the dogbone.

I machined a mandrel to a slip fit into the original hole once the brass acme inserts were removed and turned a 20 mm shaft on it on centre.(mandrel is 1.5" stepped to 20 mm)

I slip the mandrel into the dogbone then put the 20 mm shaft into a collet chuck in the mill then clamp it all in a Kurt vice to ensure it doesn't move.

I then make sure I can slide the mandrel in and out of the dogbone using the quill on the mill.
Mill to whatever size you need for the ball nut then turn 90 degrees and repeat.

I'm assuming when the dogbone was made they either used a compound 2 axis boring machine or some sort of accurate fixture so am relying on this for my set up.

Dave: If you're going remember to pick me up on the way out ;)!!

Today's progress :)!

I made the upper belt covers today and the bearing retainers for X and Y.

I also added another outboard bearing to support the handle shaft in manual mode (Not really needed but as I had a couple of spare angular contact bearings I figured why not)

Last pic is for ty1295 showing how my knee drive fits inside the knee.

http://members.optushome.com.au/jg11_ij/CNC14t.jpg (http://members.optushome.com.au/jg11_ij/CNC14.jpg)

http://members.optushome.com.au/jg11_ij/CNC15t.jpg (http://members.optushome.com.au/jg11_ij/CNC15.jpg)

http://members.optushome.com.au/jg11_ij/CNC16t.jpg (http://members.optushome.com.au/jg11_ij/CNC16.jpg)

http://members.optushome.com.au/jg11_ij/CNC17t.jpg (http://members.optushome.com.au/jg11_ij/CNC17.jpg)

Thanks a bunch for pic.

I think you made my desicision on which way to go now.

I can picture it in my head now (little pun)

Your work on it is top notch.

Dave: I'm not into rugby! Yep i'm one of those few South Africans that's not rugby crazy! LOL! If i can arrange that the Aussie teams beat our local guys everytime you must supply all the spares as well! LOL!
Ian: I suppose you ended up with a stiff neck to maneuvre that drive into the knee, it looks very good/professional!

Klox

ty1295: Very welcome.

Klox: Nah just drilling and tapping the 4 mounting holes was hard the install went smooth as silk and very quickly :)!

I'm making the lower belt covers and motor covers today then sort out the cable routes and I'll get into the X and Y BallScrews on Monday!! All downhill from here !

Nice Limit switches Ian,

Looks like you are going to be using 6 overtravel switches and 3 homing switches, good move!!

Quality limits like those will give you a nice repeatable homing position, well done.

Really nice work IJ!
I've seen companies bringing their commercial CNC conversions to international fairs and not not looking half as professional as what you're doing. Thanks for showing us the details. This stuff should be serialized for when this thread is forgotten. Hey cnczone.sir do you hear?

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Trolly is done !

I got some aluminium C channel for the limit switch mounts today and a heap of stainless capscrews to bolt it all on.

I hope to get the limits done tomorrow then the cables on Saturday and see how this thing runs....

http://members.optushome.com.au/jg11_ij/CNC22t.jpg (http://members.optushome.com.au/jg11_ij/CNC22.jpg)

Your quality is still amazing me.

Keep the pics coming.

Giving me ideas by the handful.

Ian,

The trolley looks very cool, hope you not color blind as it seems that you are now ready to wire up our controller, lol. Keep it going buddy.

ty1295: Thanks and if there's anything you'd like to know/see just ask and if I can answer/take pics I'll be happy to!

Dave: LOL I'm pretty sure I'm not but will be triple checking each wire just to make sure.(there's so many of the damn things ;) )

I was going to mount everything in a wall rack but decided it's easier if it's on a trolly as I can wheel it into the middle of the floor to work on it!

Today's efforts :)!

I made the T Slot hardware from 6061 then had to go out to chase some wire and a few bits and pieces so only finished the X axis!

In the pic you can see the C channel I got for Y and Z and for X I used the stock T slot from the autofeed trip.

I made the trips offset (in the Z and Y) so the Home can never trip the Limits no matter how I adjust things.

I'll put a few hours in tomorrow and see if I can't get it ready for wiring around lunchtime.

http://members.optushome.com.au/jg11_ij/CNC23t.jpg (http://members.optushome.com.au/jg11_ij/CNC23.jpg)

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IJ

I have to say I admire your work, it is first-class all the way. I only hope my projects come out 1/2 as good and I will be happy.
How did you make it so the "home" switches don't trip the limits? The X and Z have little posts that contact the switches but what
contacts the switches in the Y? I can't tell from the pictures.

Thanks
Brian

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Yes we do follow your installments. It looks like someone else does too. It's at 1535 hits just now.

If you need any criticism, I have now carefully scrutinized all the pictures to find something wrong.
And finally I did! The door of your cabinet have no ground strap. Finally something not perfect. :p

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Nice work!
2 questions:
What is the parent Mill?
and
Have you considered the safety issue of having those handles spinning without some type of guard?

Steve

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The handwheels on my mill have no handles, they are just aluminum wheels. Also they are like you describe, you have to push them in to engage. And there is (sorry: was) a spring pushing them back out. This is because it had power feed. And yes, the wheels would rotate driven by the friction, but I could stop them with one finger. I recommend wheels like that, because you could push them in to engagement with your body. Plain wheels will be less probable to hurt you then. But it is less convenient to turn them by hand.

Now there will be no wheels. The drives will need to move the axes also in manual mode. I want handwheels, but that will have to be a "fly by wire" system. And I can put the "handwheels" wherever I want. They just need to feed the drives with step and direction pulses. And they will of course not spin when in CNC or "power feed" mode.

If there is interest, I could elaborate on how to do this. My idea is that the PC may not be beside the mill at all times, and the beast should still be available as a "manual" mill then. But the drive cabinet "belongs to" the mill.

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Ok. I'll put it up on my webpage and post a link here. Yes, I also think of a pendant with small handwheels. But I want it to work without the PC being present.

But it will not be done in a few days. I have 60 litres of paint, and it's still in buckets. Anyone know how to build a CNC housepainter? Oh, sorry. I know. My house needs paint now. :-)

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Nice progress bud!

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Originally posted by IJ.
Loffy: LOL Hi ya !! you do realise this is all your fault :D!


Must be my persuasive mind... and I gladly take the blame for this
:D

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I have been following this thread and must say what a nice piece of work!! I wish I had the time to try to build this.

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IJ, i think you did very well thus far! I know everything will work out just fine.

Klox

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Good job, IJ

I'm waiting to hear how you like the performance of that Z axis Knee drive, whether it can stand the heavy use that I imagine for it. You don't mind being a guinea pig for research, do you? :D

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I had another guy tell me he made a 4" air piston.

Hooked it to knee, instant adjustable counterweight just add/decrease air pressure to get close to no load on knee. Seemed reasonable to me -vs- hanging 600lbs or so off back of mill.

I am also very curious on performance of knee, as I plan to do almost identical on mine providing yours works out well.

ty1295: Now that's a cool idea :D!

I have an Excello Knee mill that is fitted with a ballscrew jack for operating the knee, with a 840 oz/inch step motor for operation , one turn of the motor moves the knee .050. The jack drive shaft comes out of the knee casting at right angles to the screw, so the motor is mounted horizontally to the side. There are two large 2" diam air cylinders used either side for counter weight control, they have an automatic pneumatic pressure release valve that keeps constant pressure whether raising or lowering.
The motor is fitted with a holding brake to prevent back feeding when not moving.
The knee can be jogged by pulse steps or run continuous.
This mill has a Z axis on the quill, so the knee control is just for initial positioning.
Al

Yes, the air cylinder counterbalance sounds like a good idea! If a person was going to be using it constantly (as IJ will), do you think it would work to plumb the cylinders to a large air tank "accumulator", so that the pressure would maintain a steady rate, no matter where the cylinder was on its stroke?

Hu, Essentially that is what this system does, it is a special constant pressure and relief valve, I think even if you had an accumulator you would still need the relief when on the downward stroke, Likewise you would need automatic top up as the cyclinder rises. This system works well. I don't know who makes the valve assembly, I think a spare came with the machine so I will try and look for a name.
Al

If the accumulator have a volume much larger than the displacement, it can be a closed system. That would save having a compressor running. The piping between cylinder and accumulator should have ample dimensions, dependin on max Z feed rate. There is no need to make the knee absolutely "weightless" in all positions.

OTOH if you want air assistance of the acceleration, a two-way cylinder and active control would be needed. Probably will be cheaper to use a more powerful servo.

I've seen used long stroke gas cylinders like the ones used for tailgates. It's simple and maintenance free.

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Three cheers for IJ,

What a great job, I am back from the trade show now after having to extend my time away from the office. I don't think counterweighting will be necessary in Ians case 700w @ 4:1 red. x 5mm Pitch should be a walk in the park.

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Are you suggesting the quill is easier to do then?

What would you do different with knee and what is the issue causing it to be so slow to not be usuable?

I suspected that you may have this problem with the knee going by the Excello I have with the powered knee. The motor and reduction I have is almost the same situation as you have and I would not want to use it for machining purposes as it is.
The Z quill on this machine has a ball screw mounted in a square tube enclosure parallel to the quill, the tube is slotted and a short operating bar is mounted with the ball nut on one end and the other end is pinned to the quill, the motor is mounted parallel to the Tube assy with the drive shaft at the top, with the timing belt coming off the top of the motor to the top of the ball screw.
These machines were originally manual machines that were converted by an OEM.
I have the original blue print of the Z axis assy, If you are interested I could try and get them scanned and displayed.
Al

I would be interested also, as I am about to do the same as IJ and following this closely, and undecided on Z yet.

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I found an Anilam retrofit manual online today that had some good pictures.

I have several anilam controls at work, and hate every one, but the manual gave me some good ideas on the quill.

I was searching for bridgeport ballscrew on google.

I too am awaiting pics, as more is always better.

I think you just convinced me to do the quill atleast for the first go around.

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This is a couple of shots of the arm from the ball screw to the quill and one of the front of the ballscrew enclosure with front cover off.
Al

encl

Thanks Al :)

When I purchased a used Shizouka knee mill that had been retrofitted, I took one look at the quill-ballscrew connection, and laughed. It has about a 1/2 square piece if keystock, with a hole drilled lengthwise through it, fastened to the spot where the scale indicator used to be on the quill. You could see this connection flexing about 1/32 inch every time the Z reversed direction. What a piece of crap! :D

But this seemed to be about all they could do, without doing it right, because this was the width of the slot in the front of the quill casting. So, I completely disassembled the head, and remilled the slot in the front of the casting to a little over 1 inch wide. I also increased the length of the slot as much as I could.
After this, I was able to mill and drill the front of the quill for a 3 bolt attachment, about 1" wide, and 2 inches long. To this, I attached the ballnut. This is very nice and rigid.

I also took all the gears out of the head. I made some polyV belt pulleys, for a high and low range. Low range is up to 2400 and high is up to 5000rpm. Both sets of pulleys are permanently mounted inside the belt housing on top of the machine. I just loosen the motor and slip the belt onto the other pulleys when changing ranges. This is not convenient for speed range changing within one program, of course.

For what I do, most of the time, the machine is running in high range anyways. If I have some larger threads to tap, I will most often plan to run the entire program in low range. But, with thread milling being a lot more fun than tapping anyways, a guy can safely run in high range. If you get a vfd with encoder feedback, even in high range, the torque is pretty good at low rpm commands. To try to ensure adequate power for tapping and face milling, I upped the motor from a 3 to a 5 hp while I was redoing the head.

I'll try to take some pics tomorrow if you need further clarification, but it is pretty much as I explained it.

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I did a scree capture from the Anilam manual showing the quill assembly.

Still interested in others pics/drawings though for my conversion.

Thanks to IJ, think I will start with quill and if I need more travel do the knee later.

http://s94691562.onlinehome.us/gallery/album12

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I think you should build 2 and send me one so I can confirm how well your construction skills are and let everybody know. GRIN.

I see the 4 bolts that hold it on, still not sure what they thread into as they are too small to be the head alignment bolts, unless they drilled and tapped those nuts or something.

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Shizouka quillbox retro

The quill is fully retracted to the top. The brown colored rectangle is the ballnut mount block. You can see a large hole through the face of it. Before the ballnut is mounted, you can imagine that I insert a large allen capscrew through this hole, and it passes right through to the back side of the hole, and screws into the quill, which was drilled and tapped for this. That would be a 1/2NC capscrew. This is one of three screws that fasten the nutblock to the quill.
The nutblock also has kind of an apron that extends downwards. The apron is hidden by the flange of the ballnut, but it is in behind there. A couple of 3/8" capscrews fasten through the apron into the quill. Because the quill is only about 1/2" wall thickness to begin with, and a large flat has to be milled to receive the nutblock, there is not a lot of wall left to actually hold the tapped threads. I took a lot of care to tap them as deeply as I could, and custom fit the capscrews so they would not quite bottom out.

You will notice a second vertical rod parallel to the ballscrew. This is my "coolant swing device". It has a long slot in it, with a bit of a helical twist in the slot near the bottom end. A projecting finger (mounted on the lower baseplate) runs in this slot. When the spindle fully retracts for a tool change, the helical twist of the slot forces the rod to rotate a little bit. Since the coolant line is fastened to the end of the rod, it swings clear. This permits the toolchanger arm to clamp on the tool without messing up the coolant nozzle position. Afterwards, when the tool rapids back down, the reverse motions occur, and the coolant nozzle is back in position.

different angle on same.

Because I had to remill the slot in the main housing anyways, I also faced off the entire front of the casting. As you may know, the front surface of most of these manual mill heads, is not a very nice place to bolt something on that will be parallel to the spindle bore.

This made it a lot easier to make a large 3/4" plate to bolt onto the face of the main housing. Then, everything else bolts to that.

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Dear IJ,

First of all, your work is beautiful. I am in the middle of retrofitting my knee mill as well. I am driving the knee for Z, so I was hoping your design was going to work well.

Could you clarify the problem you had with driving the knee for the Z axis? Was it that the motor couldn't move the knee very well (not enough torque?) or was the rapid rate not fast enough (not enough rpm?). Also, was the 700watt spec for the motors for continuous or peak?

I know that others have driven the knee axis, but the one I know of used gas springs for counterbalance to increase the rapid rate.Thanks.

Regards,
Rick

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Dear IJ,

I'm an ultra newbie as well, but I believe M03 is a clockwise (forward) spindle start command, usually accompanied on the same line by a "S" command for spindle speed in RPM, i.e. "S1000 M03". Don't know if that helps.

Thanks for the reply on the Z knee drive. I will hope my motor has enough grunt at 1600watts.

Regards,
Rick

Dear IJ,

On second thought, maybe if your CNC controller is not controlling the spindle on-off (i.e. you turn the spindle on manually), you don't need the M03?

Regards,
Rick

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Yes, M3 is a spindle on command.

I am thinking you don't have that active in Mach or is looking for the S command as mentioned.

FYI M5 at end is for spindle off.

M4 usually is counterclockwise
M3 clockwise.

I remember which is which, by remember how I draw a # 2. Clockwise.

G0 or G00 is Rapid or GO FAST
G1 Linear the 1 is a line
G2 Clockwise arc, again remember the 2 thing
G3 is Counter Clockwise (the other way)
G4 is dwell

Could go on, but those 5 may help you get started.

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M3 is spindle forward.
M4 is spindle reverse.
M5 is spindle stop.


G2 is clockwise motion of the tool.
G3 is counterclockwise tool path.

Best not to confuse M and G codes. :)

Pete

Ian( and anyone else who is interested),

The problem is coming from your arc commands in the above test program. The centre values of the arc in the test program are absolute centres, deskCNC requires (as most programs do) incremental centres. If you look below I have made some changes to all of the arc moves, give it a go and let us all know how it went. Note: the reason it said that the error was on line 5 is because DeskCNC looks ahead and throws up the error on the line before the problem. If you look at the code, the first arc command is on line 7 but in deskCNC if you look at the actual number on the side of the screen (not the program sequence numbers) you will notice that the first line is acutally line 0, hence the first arc command is on line 6 and the program stops on line 5.

N004 G90
N005 M03
N006 G00 Z-2
N007 G00 X10 Y0
N008 G00 Z0,5
N009 G01 X10 Y0
N010 G02 X-10 Y0 I-10 J0 (line change : I-10)
N011 G02 X10 Y0 I10 J0 (line change : I10)
N012 G00 Z-2
N013 G00 X5 Y0
N014 G00 Z0,5
N015 G01 X5 Y0
N016 G02 X-5 Y0 I-5 J0 (line change : I-5)
N017 G02 X5 Y0 I5 J0 (line change : I5)
N018 G00 Z-2
N019 G00 X-15 Y0
N020 G00 Z0,5
N021 G01 X15 Y0
N022 G00 Z-2
N023 G00 X0 Y-15
N024 G00 Z0,5
N025 G01 X0 Y15
N026 G00 Z-2
N027 G00 X-10,61 Y-10,61
N028 G00 Z0,5
N029 G01 X10,61 Y10,61
N030 G00 Z-2
N031 G00 X-10,61 Y10,61
N032 G00 Z0,5
N033 G01 X10,61 Y-10,61
N034 G00 Z-2
N035 G00 X15 Y0
N036 G00 Z0,5
N037 G01 X15 Y0
N038 G02 X-15 Y0 I-15 J0 (line change : I-15)
N039 G02 X15 Y0 I15 J0 (line change : I15)
N040 G00 Z-2
N041 G00 X0 Y0
N042 M05
N043 M2

Give the above program a go now it should work. Basicall in an arc move X centre = I, Y Centre = J, and the Z Centre = K. You will only be able to use the Z (K) as a centre if you are working in the planes of G18 or G19. To put it as simple as I can, the I and J values in the above EDITED program example tell the controller, "How far incrementally is the centre of this arc in X (I) and Y (J) from where the tool is situated at this present time. The X and Y movements in the arc command are telling the machine where the ABSOLUTE end point of the move is.

Hope this helps.

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IJ: You are going to have to pick up the pace. :D :D

I just got my 2nd motor mounted last night. Of course I have a lot of wiring, and the Z axis to go but didn't think I would catch up to you this fast.

I have the added bonus though of playing with G-Code for the past 5yrs full time, and 5 on and off before that.

CNC's are not new to me, retrofitting is though.

I will give you credit though. Looking at yours gave me ideas which helped to speed me up. My mounting isn't as nice as yours either, but so far appears it will work like a champ.

If I stop long enough I might even take some pics.

Jeff

LOL Jeff,

Get the pics up ASAP :)

Dave: Still came up as an error on line 5 ??

Not to steal IJ's thread. Figured be better to keep on one great thread. And since i have been hitting refresh every hour waiting for his progress here is mine.

Got pics of the mounts on my mill. Not nearly as fancy as IJ's but should work. Will add some bracing to X axis, and covers as time permits. For now very usuable and stiffer than I expected.

http://s94691562.onlinehome.us/gallery/album12

Now get those Z axis prints for me. GRIN.

IJ, I've got a new project in mind for my company and it might need some major mill work done. I was thinking about the possibility of buying a mill myself. How much did you pay for your knee mill if you don't mind me asking.

Ian,

I overlooked one silly little thing in the program. All the decimal values have comma's instead on decimal points. So give this one a go. You can stipulate in DeskCNC if you want the separators to be comma's or points but rather, I have made the changes for you.

N004 G90
N005 M03
N006 G00 Z-2
N007 G00 X10 Y0
N008 G00 Z0.5
N009 G01 X10 Y0
N010 G02 X-10 Y0 I-10 J0 (line change : I-10)
N011 G02 X10 Y0 I10 J0 (line change : I10)
N012 G00 Z-2
N013 G00 X5 Y0
N014 G00 Z0.5
N015 G01 X5 Y0
N016 G02 X-5 Y0 I-5 J0 (line change : I-5)
N017 G02 X5 Y0 I5 J0 (line change : I5)
N018 G00 Z-2
N019 G00 X-15 Y0
N020 G00 Z0.5
N021 G01 X15 Y0
N022 G00 Z-2
N023 G00 X0 Y-15
N024 G00 Z0.5
N025 G01 X0 Y15
N026 G00 Z-2
N027 G00 X-10.61 Y-10.61
N028 G00 Z0.5
N029 G01 X10.61 Y10.61
N030 G00 Z-2
N031 G00 X-10.61 Y10.61
N032 G00 Z0.5
N033 G01 X10.61 Y-10.61
N034 G00 Z-2
N035 G00 X15 Y0
N036 G00 Z0.5
N037 G01 X15 Y0
N038 G02 X-15 Y0 I-15 J0 (line change : I-15)
N039 G02 X15 Y0 I15 J0 (line change : I15)
N040 G00 Z-2
N041 G00 X0 Y0
N042 M05
N043 M2

Enjoy

Dave

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CF: Forgot to add the prices are in Aussie $$$! 1 AUD = 0.69c USD at the moment.

Dave: Just ran the code and it works fine thanks! :)

Thanks for letting us know IJ, good luck with the quill retro. :cheers:

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Excellent work IJ!
Isn't it boring just standing by and looking at the mill working? :p

And excellent picture. I could make a copy of your house keys from this hi-res picture. :bat:

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IJ, What size motors are you using? I am trying to determine what torque would be required for a Bridgeport Series 1 Mill.

Thanks
Steve

Ian,

DeskCNC will interpolate all 4 axes. Call me about it, there may be a setting you are missing if it is not.

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IJ,
What you've done so far with your quill looks good.

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IJ, you must stop posting all of these beautiful pictures for me to stare at. How am I supposed to get any work done with thoughts of knee mills going through my head;)

IJ,

Don't worry, we're all just in awe and speechless! (Well, at least I am). I've been working on my retrofit for the last 6 months and I've not even done a third of what you've done in a month. Well, I guess that's the difference between a real machinist and just a wannabe like me. Keep up the good work, I'm checking up on you several times a day.

Best regards,
Rick

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You've made a fantastic job. :)
On top as a final you have to post a pic on a 3D-piece made with the machine. ;)

Cheers,
Sven

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I think you deserve to go out and get yourself an ice cold slab of VB IJ. Great work, hope you get it honk'in this week.

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IJ,

May I have more info on the home and limit switches you're using (such as manufacturer and part number if you have it) as I should start thinking about ordering some soon.

Your progress is fantastic. I know I'm going to have some problems figuring out the wiring/electronic stuff because I don't have much background. Do you have any other sources of info for hooking things up, or are you just gifted in that area as well?

Regards,
Rick

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I usually use this type of Honeywell http://catalog.sensing.honeywell.com/datasheet.asp?PN=14CE2%2D1&FAM=limitandenclosed&P=5812,6530,6522,6271
They have a hermetically sealed cable attached and are often found on ebay.
Al

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IJ,
For what it's worth, you may need some kind of diode thing on the relay coil ciruit to absorb the back emf when the coil is released.
In my lathe retro, the PC talks to a mini-reed relay board with the diode protection on. This mini reed relay in turn controls the ice cube relays which control the contactor coils.

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Are you using optically isolated I/O along with the seperate external power supply?

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You can buy two kinds of I/O boards, the good ones have optically isolated inputs. This prevents external electrical signal noise and currents from working into your PC. The only communication then between your external power circuits and your PC circuits is through the optical isolator which uses light to transmit the info bit or state.

Its just some more $$ to spend that you weren't counting on :D

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I believe so, yes. The opto isolators are very low current devices, If you purchase a commercially made PCI i/o card, they will be in the correct place :)

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IJ, What exactly is the symptom you are getting with the relay problem?
Al

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I assume the serial board relays are picking up 12v relays that in turn pick up the contactors. I am not familiar with DeskCNC and how it effects its e-stop circuit but , have you tried just picking up the serial board relays with out the others hooked up? In order to isolate which relays are causing you problem.
Do you have the hook up in schematic form you can post? Also as well as the diode across the dc coils as Hu mentioned you should use RC suppression across the AC contactor coils, many manufacturers make them for their contactors or if you post the contactor size I can give you an idea of R C value to custom make one if you wish.
Al

Are your inputs filtered? If not your problem may be that they pick up noise. Also check if your software can filter (debounce) them. Hardware filtering is preferred. This suppresses noise where it is received and should be used in addition to suppressing it where it originates as Al suggests, not instead of.

Look at it like a radio link. You want both a weaker transmitter and a less sensitive receiver.

Appropriate grounding is also important to increase the ratio between signal and noise.

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Inputs: Limit/home switches, Estop, ready/fault output from servo drives.....

One other thought: I see you use a laptop. I have lots of problems using a new(ish) laptop serial port connecting to different control equipment. Sometimes it plainly will not communicate. In other cases it will for a while but get errors very easily. My old laptop does not have these problems. If you get cornered, try a home/office PC. I checked it, and the voltage swing on the line sending data from my laptop to the controller is marginally inside the RS232 specs.

It sounds to me like typically like a spike on the AC supply line, usually the difference with laptops and desktop PC's is the power supply on a laptop is not referenced to ground. On a desktop PC the incoming ground is connected to the PC chassis and the PC power supply output is also referenced to ground, I would wager if you use a desktop PC it would work.
What you could try is to connect the common output of the serial port to a solid ground and also all power suppy commons should be connected to a common ground point also.
If you have a 120 or 240 volt control power isolation transformer make sure also that it has a neutral connected to ground. Alot of the problems I run into in retrofits is not abiding by this method. I always use a large copper ground plate that is tapped to take termination screws and ground ALL machine grounds at this common point and this eliminates just about all problems of this kind.
Unfortunately Laptop PC's were not intended to run CNC machines.
Al

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Again please. What exactly did you do?
No changes in the way parts are connected, you just physically moved the relay and contactor out of the cabinet?

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IJ. If you want to suppress the spike from AC contactor coils, use a .5mfd non-polarized non-inductive capacitor in series with a 220 ohm 1 watt resistor across the coil.
The capacitor voltage rating should be at least twice the coil operating voltage, it also works for solenoids etc.
Al

Al, is that correct that one should use a 500 uF capacitor (0.5 milli-Farad)? If the contactor op voltage is 240 VAC, a 700 VDC, 500 uF non-polarized capacitor is going to be expensive (not to mention difficult to find)!

Or maybe I'm just talking through my hat :)

(^- first time to use that expression! I hope it means what I think it means; that maybe I don't know what I'm talking about? *smile*)

Arvid

Arvid, The value I meant to list was 0.5uf not 500mfd , the mfd stood for microfarad as I did not have the mu symbol to hand.
Al

Arvid: I think those non-SI units makes you confused as a fart in a basket chair.
That should be a 0,5mfd as in micro-Farad capacitor.
It's easier to handle than a 0,5MF capacitor. ;)

IJ: If moving the relay out of the box helps without doing any wiring changes, I would not trust it to always work. I looked at your control board on http://www.cnc.yertiz.com/deskcnccontrolconnect.htm
Look at the paragraph "Because of the the risk of crosscoupling....." It seems they have encountered such problems before. I can see no filtering on this board except for some capacitors that will do little or nothing without resistors in series with the signal.

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Originally posted by ESjaavik
Arvid: I think those non-SI units makes you confused as a fart in a basket chair.
That should be a 0,5mfd as in micro-Farad capacitor.
It's easier to handle than a 0,5MF capacitor. ;) *snip*

Just to make it clear, (some of) the SI prefixes are:



Factor Prefix Symbol
10^6 mega M
10^3 kilo k
10^-3 milli m
10^-6 micro µ



So 0.5 mF (milli Farad) = 500 µF (micro Farad). Don't know where you got the mega from :)

Oh, and don't ever use 'm' as a substitute for 'µ'. You'll be off by a factor of 1000! If there's no way to write a µ, use u instead - this doesn't collide with any other SI prefix.

This is the kind of thing that makes space probes run off in the wrong direction... :rolleyes:

Arvid

Just a thought, but could the magnetic fields of the relays working cause the problems with the e-stop?

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Electromagnetic interference from relays is often overlooked, as well as the volatge spkie when they're deactivated (can peak at a couple kV).

By the way, you've done an excellent job with the mill. Given me a good idea what to do with the spare harrison mill i bought. Just need to get a plasma table built first.

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EMR is overlooked by a lot of people (including those wonderful people who design european ford cars, who put an ecu sensor in between 2 sparkplugs and ran the cable along side the plug leads, needless to say, the resulting erratic tacho was only one side effect).

Currently I'm just designing the table, which is going well with the help of this forum. I won't be starting the construction of anything for at least another couple of weeks, as I'm off on holiday on wednesday.

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I guess the :cheers: time is near IJ, go get 'em dude, chips will be flying soon.

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Everything is a tramm to you Melbournites, lol. Can't wait to hear the results.

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Not sure deskcnc can open an inventor file directly.

Never used deskcnc myself.

You probably will need to save as a dwg or dxf file (2d :mad: )

If you want to email it to me jscott@airtomic.com I happen to have inventor here, as well as a cnc package that can read it directly. Be glad to make a program for you for the first few test cuts.

Thanks TY.. you have mail! :D

Congrats IJ! In my mind this has been the most professionel retrofit I've ever seen. Now where are my videos;)

Al_The_Man: I can't find a source for the Honeywell 14CE2-1 limit switches you use.

Will these Omron D4C limit switches work the same? There is a Roller Plunger D4C-1602 and a Sealed Roller Plunger D4C-1632 available. I'm assuming I want the Sealed Roller Plunger?

Also comes in a 5 meter cable length, or is 3 meters enough? Thanks for your help.

Product data: http://rocky.digikey.com/WebLib/Omron%20Web%20Data/D4C.pdf

IJ: Congratulations! Sounds like everything is working well. I am going to miss your daily posts once you've finished. I have become rather addicted to this thread.

Regards,
Rick

RJ, think Honeywell were the first but there are some knock-offs that are the same as you have found. Incidentally you can get the roller wheel at right angles or in line, they also stack well as in when you have a home limit and over travel together. You just have to set the home striker to hit its respective limit first.
The cable length depends on where you exit your electrical cabinet, the longer one will usually take you right into the terminal strip with a small knee mill etc.
Al

An example of how they stack for home and OT.
Al

IJ,

Save the inventer file as a dxf for 2-d work or an stl for 3-d stuff, desk cnc will read these two formats to output g-code.

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IJ,

If you command "F100" you are setting the feed rate of the move to 100mm/min.

If you command a G01 (linear @ move feed rate) it will move at the "F" value you have set. Once you have set the "F" value (in this case 100) it will feed at this until you change the value as it is a modal command.

EG:

G01 X60 F125

Will move the machine +60mm absolute from the datum point at a feed rate of 125mm/min.

G91 G01 X60 F200

Will move the machine incrementally +60mm from where ever the tool is at the time at a feed rate of 200mm/min.

If you want to make a move as described in you post you would command the two axis positions on the same line to produce a taper.

EG:

G01 X60 Y20 F125 (to the point you wanted)
G01 X0 Y0 ( to return to the XY 0 position)

If you ever use G91 for incremental moves you must command G90 to return to absolute positioning.

G00 will ignore the "F" feedrate and rapid traverse the machine at what ever the maximium travel speed is that you have set the controller to run at.

G codes are modal as well (at least most of the are anyway)

In a multi line program you only need to comment the g-code command once until you want it to change.

EG: (Modal g-codes and feedrates)

G01 X60 Y20 F125 (Linear move @ 125mm/min feed)
X120 Y40 (Linear move @ 125mm/min feed)
X0 Y35 F200 (Linear move @ 200mm/min feed)
G00 X120 Y40 (Rapid travers move feed rate ignored)
X60 (Rapid travers move feed rate ignored)
G01 X0 Y0 (Linear move @ 200mm/min feed)
M2 (program end and rewind)

Hope this helps

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IJ, you want me to send over some files I've written in Onecnc so you can see a real life part cut?

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Sure. Here is a code designed for Mach1/Mach2.

1/4 end mill for the first cycle and a 1/8 for the second (it is *possible* to use the same for both though).

Something to note on G90 G91 (Incremental -vs- Absolute)

In general it is prefered to run Absolute to avoid a stack up of error on incremental.

For example if every move is off .001 inches in absolute the CAN start to add up.

Here IJ, did a quick code for you to run. :D :D

Kept it simple to start, I could have output code for a custom minature billet wheel but........

N1 G20 G90 G40
N4 G28 G91 Z0
N5 G28 X0 Y0
N6 G90
N8 G54 M06
N9 T01 M01
N10 S2000 M3 M41 M7
N11 G0 X0.4157 Y0.5457
N12 G43 Z0.1969 H00 M7
N13 G1 Z-0.1969 F0.98
N14 Y1.5299 F1.97
N15 G0 Z0.1969
N16 X1.5969 Y0.5457
N17 G1 Z-0.1969 F0.98
N18 X1.8593 Y1.5299 F1.97
N19 X2.1218 Y0.5457
N20 G0 Z0.1969
N21 X1.6953 Y0.8737
N22 G1 Z-0.1969 F0.98
N23 X2.0234 F1.97
N24 G0 Z0.1969
N25 X2.778 Y0.5457
N26 G1 Z-0.1969 F0.98
N27 Y1.5299 F1.97
N28 X3.2373 Y0.5457
N29 Y1.5299
N30 G0 Z0.1969
N31 G00 Z4.0 M09
N32 Z0 H00 M19
N33 M30
%

It output in inches, being us arrogant americans tend to like that goofy system.

Thanks for pointing that out Ty1295! I'm new to the g code and haven't got my post on Onecnc tuned exactly right yet.

Originally posted by Cold Fusion
Thanks for pointing that out Ty1295! I'm new to the g code and haven't got my post on Onecnc tuned exactly right yet.

Your code output in Absolute

N100 G00 G90 G54

It ran in Mach2 for me so must be doing something right.

I should add that I'm using the arrogant American system as well.

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I'm one that has never posted here, but being part of the 7000+ viewers, I just wanted to say that this thread is a real enjoyable education for me......More pics! .....can't seem to get enough of the interest you generated here.
Bloy

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Just ad an Fx on the same line as the first G1

N009 G01 X10 Y0 F10
for example.

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There might be a default speed in your controller software, or it might be using the max speed you have the motors set to.

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No worries IJ,

e-mail me your stl file and we will go through it.

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Very nice IJ! Have you done any work that would approach the limit of the machine as far as ridigity? I am very curious as to how well this type of mill preforms.

PS, still battling my drivers. The people here have given me some suggestions and I can't wait to try them out tomorrow in hopes that one wll fix my problem.

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I would love to get a knee mill similar to yours and retrofit it in the future. Ebay is not a bad place to pick them up used. I've seen suitable ones go for just over a a grand, with tooling.

Maybe I missed this in the thread but have you been able to get a good reading on the accuracy?

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Great thread! I'm about to finalize the purchase of a used Bridgeport clone this week, with the hopes of converting to CNC.

IJ, you said you still have complete manual control if you ever want it. How would you manually move the quill? Or can you only move the knee when in "manual" mode?

Also, what is the long travel of the table? What was the travel before the conversion? And what is the table size of your mill? I'm looking at a 9x42 mill (only size in my area), and I will need every last bit of the 30 inch travel for the work I want to do with it. I am figuring I will have to make some sort of extension about 12 inches long that is of a smaller cross section than the table, so that the stepper/servo will not hit the knee and limit the travel.

Finally, could you have mounted the servo for your Y axis so that the motor pointed inwards? That should have given you more room for your legs when standing in front of the machine. Was there a reason you chose to do it like you did?

Thanks,

Nick

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Nick,

Attached is an image of my Y-axis motor mount in progress. As IJ said, facing the motor inward makes the belt pretty long.

Regards,
Rick

But it shouldn't really matter if the belt is long, does it? I mean, they are usually steel inforced or similar.

Cheers,
Sven

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I'm glad you still have your finger :)

I did not quite understand your answer for manual Z axis control. Are you saying you can still move the quill using the original lever if you reinstall it? Wouldn't you have to disengage the ballscrew in order to do that?

Thanks,

Nick

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Great job IJ! beautiful workmanship.

I have just spent the last 1.5 hours reading this thread (I should be programming;) ).
I'm kinda of a mechanical freak myself. I love to build stuff from my own ideas (original or not) as it is very satisfying when complete.
I am also a business man and need to make profit to stay in business.
Brings me to the question of money.
How much did all this cost? The retrofit not the base machine.
How many hours have you logged to get to the point of making chips?
Would you do this again or buy a working CNC next time?

Thanks for thread and great documentation.

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IJ
Mentioning using the CNC to make the parts for the lathe conversion kinda makes a guy wonder about development on the first machine.
Sombody must have used a chisel, file and sandpaper to fabricate the first hand hewn miller. Then used the half-assed hand made jobbie to build a better one, and then.....you get the picture.

Yep that must of been how it happened (although i belive the lathe came before the mill,mainly to do with the spindle)

Also look at any of the threads anout building a second router, everyone uses their old router to cut parts for the new. My philosophy about cutting aluminum goes hand in hand with that type of construction, that is any machine can cut aluminium you just need to go slow and if you need a good finish take off say.01 or even .005 in your finish pass full depth

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It: I believe your correct that the lathe came before the mill.
Speaking of ship parts and machining. I read somewhere that back in the good ol'days before national standards if ship builders needed to fasten something they would just arbitrarily (spelling?) turn a helix on a shaft (normally wood) and hand fit a nut to it. Must have been son-o-***** trying to replace parts.

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You really seem to have this CNC thing kicked already IJ, nice Jig, well done. :cheers:

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Originally posted by IJ.
Nick: I'm glad to I like that finger ;)!

Yes the original lever just clips back on the shaft with a ball bearing detent!

I leave the BallScrew engaged and it just adds a little drag (I have to say though the only time I'd use this is if there was a power failure and I needed to raise the quill or if when I finally get around to enclosing the belt to back off from a limit switch if I misjudge travel.)

OK. I'm still confused on the manual Z axis movement. You said that you keep the Z axis screw and nut physically engaged when in manual mode. That means that when you move the quill using the original bridgeport quill lever, that the force on the screw and nut causes the screw to turn???? That just doesn't seem possible to me. If that is what actually happens, is the movement free enough for drilling?

And, if that is what happens, wouldn't that imply that you would need to use some sort of mechanical break on each axis when using the mill in manual mode? Otherwise, the cutting force would cause the X, Y, or Z screw to turn and the corresponding axis would move.

I'm asking these questions because when I do my conversion I would still like the ability to use the mill in fully manual mode, for the quick and simple cuts.

Thanks.

IJ,

EG: G83 Z-10 R5 Q2 F100

G83 Is to set into peck canned cycle
Z-10 is the hole depth
R5 is the return point
Q2 means it will execute 2mm peck depths
F100 is the feed rate

:cheers:

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Originally posted by daytrader
And, if that is what happens, wouldn't that imply that you would need to use some sort of mechanical break on each axis when using the mill in manual mode? Otherwise, the cutting force would cause the X, Y, or Z screw to turn and the corresponding axis would move.
Thanks.
Yes, that's also what I found out. With no motor on the knee will go all the way down by it's own weight. There is not enough friction in the ballscrew to hold it. So I found out that when I want to run it manually, it have to be with the motors engaged. That means I'll have to make handwheels connected to encoders. Then output from these will control the power drives. A bonus is that the handwheels can be placed anywhere I like. And I did not like the original position of the Y-wheel all the way at the back on the side of the mill. Y is by moving the mill head, not the worktable on this one.

If you don't do it like that, you will have to lock each axis except the one you hold on to when engaging a cut. OK, I know we should do that also with Acme screws, but....

IJ: Did you tune the servos after mounting, or do you run them using calculated values?
Can you post the settings here, together with the gearing and screw pitch?

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Ian,

The postprocessing is a thing we will need to go over via a teleconv. Also the language file is where you need to change the button text, another thing that would be better done over a teleconv. I suggest we get together on this over the next couple of days, it will only take about 10 mins. You are really flying now I see, those parts look great.

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Hope you feel better soon IJ, lots of garlic and fluids now OK, do I sound like your Mum?

:)

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Great looking parts IJ. I know nothing about this sort of thing but they look great to me! Can you explain/show how the fixture works?
What prep does the raw stock need to fit fixture?

You should be very proud of your conversion/parts. When are the vids coming?

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IJ, What are you using to generate g-code for these pieces? Your not still hand writing it are you?

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Very Impressive IJ,

We need to get rid of that hand editing so lets catch up and get you post sorted! I have just returned from Melbourne (short trip) and Tweed heads but will be in the office today (Sat) if you want to call me.

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IJ.:
I like the look of your latest work. I would like to learn to make similar parts that have combinations of turned and milled portions. If you have time, I'd love to know how you made this part. Is it all done on the mill or was your lathe involved? How did you hold it during the process? Fixtures? Hope my newbie machining questions are not too boring. Thanks.

Regards,
Rick

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IJ.:

Thanks for the explanation. It's easier to visualize when you explain how you did it. Still seems like magic to me. Setups seem very dependent on the experience and creativity of the machinist. I guess I need to start showing some of these parts to my instructors to get some insight on how you machinists think. Thanks.

Regards,
Rick

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IJ.:

You're so fast in replying, I couldn't cover up my stupid question in time! Holding it by the stubs came to me just after I posted, so I went back to edit. The answer always seems so simple once it's explained.

Thanks for the explanations. I still think it's fascinating how some parts are machined. I can't wait to find out more about this black art's secrets! I know there's no substitute for experience. Maybe it would be easier if I were good with puzzles (I've noticed most engineers are good at puzzles).

Regards,
Rick

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IJ: I must first congratulate you on a job very well done. I've aquired the same motors and drives you have and I would like to know what power supply did you use? Thank you.

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Are those bigger parts made on the mill only??? Or did you turn/thread them on the lathe first?

Arvid

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I really enjoy watching what's possible to do on that nice (and nicely converted!) mill of yours. What kind of tolerance is possible on milled holes (dia)? Do you have any way to measure surface quality (Ra)?

Arvid

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Nice work IJ, soon you will have the military chasing you down to make some for there in house war games, lol.

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IJ, Nice job. Now that you have the mill taken care of, when is the lathe project getting underway? can't wait.

I just got my used Bridgeport and will like to convert it into a 2 axis (possibly 3) cnc. What is your opinion on the following:

1. Not using ballscrews. How accurate could the machine be without the screws? Is the software backlash compensation good enough if only conventional milling and not climb cutting were done?

2. Using 5/8 diameter ballscrews. This would probably reduce the problem you had with the dogbone that connects the X and Y lead screws. Thomson sells them brand new for about $1.00 USD per inch and the nuts are only $23 USD. This is significantly less than what they charge for the 1 inch size. The question is will the screw be strong enough?

Thanks,

Nick

Nick: If using servos, use ball screws. Acme screws does not transfer all the load back to your motors, so a servo setup will be very difficult or maybe impossible to tune to good dynamics. Also the small amount of backlash is a problem for a servo. It has a small amount of movement where there is little or no resistance to it moving back and forth. When you tune the system for good dynamics on movements, it will buzz violently back and forth within the backlash. And it will heat the motor until the drive shuts down with an overcurrent fault. Tune this out, and the movements will be sluggish.

Use steppers with Acme. They actually may benefit from the damping effect of these screws. But for a Bridgeport they should be fairly big.

Don't forget that the leadscrew can contribute more to the inertia than the table, vice and workpiece does. You can adjust this by using a gearing (like IJ does), but that could bring in an unwanted compliance or even worse: backlash. Harmonic drives are low at both, but high in price. The ratio of inertia between the motor and the load should be within the specifications for the motor, or it will be hard to tune.

5/8" sounds fine for that size mill. (Look at what professional mills of same size uses) But not much below that. Then chances of resonance increases. Think of a scew the thickness of a piano string and you understand the effect: boing..boing. Support it at both ends if running high speeds to minimize whip. Actually, do it anyway.

I never thought of the problem with tuning if using servos. I might use servos, so I would like the potential of a good zero backlash system.

I thought new bridgeport ballscrews were just slightly smaller in diameter than the conventional bridgeport acme screw. But if all I have to worry about is reduced rapid traverse speeds, I can live with that.

Now I have to focus on wiring up the machine and fixing a noise in the head. It sounds like a belt noise (vari-speed head). A very loud thump. Any ideas what it could be?

Once I get the machine running well, I can decide how soon until I go the cnc route.

Thanks.

I don't know the BP, but could this be the sound of the splice in the old type flat belts? Is there such a belt in it?

And my mill just made the first cuts with no hand wheels today. Z is still hand fed, but not a problem with the parts I need just at the moment. And I'm out of the chicken and egg problem and can get the remaining parts for the mill made too. I'ts been a headache making the necessary parts with no mill large enough to take the parts.

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I have a couple of questions about your conversion (which Im very impressed at to say the least).

1) where, how, what was the dog bone used for and can I see a photo of it in place as that bit seems to have been skipped in the thread.

2) Can I see a piccy of the Ball Screw Yoke actually connecting into the Spindle on the z axis and how its all mounted together as I am unsure what you did to make this work.

Im thinking of getting a bridgeport copy similar to the one you have and doing a conversion and this is all very helpful.

Cheers,
Tom

IJ: I have the same motors and drives as you and for some reason or other, I can't get the motors to run!
Do you happen to have a diagram that shows the motor to drive connections and to parallel port?
What values did you tune your motors at?

Cheers!

Does that include the dog'n'bone?

Im gettin all excited!

Cheers,
Tom
:banana:

Oh one other thing...you said in your retrofit you used the ballscrew for the quill from left overs, did you buy oversized screws for this purpose and how did you seat the Z screw into the bearing?

This is quite a complex project as you have found out and I am learning :)

Cheers,
Tom

Guy's Give me a bit of time and I'll put something up.

Kookaburra: :cheers:

IJ. I wonder if I could buy a length that would fit with no turning, I mean perhaps a length used for the Y axis could be used...hmm I dont have a lathe IJ. fancy some paid work? :)

Cheers,
Tom

My old school used to have a metal working lathe, I wonder if they will let me borrow it for a donation.

Anyhow, this is going to cost a packet anyway so money is not my concern, postage will have to be paid for most of my stuff from the USA (geckodrives, ballscrews, servos) so whats a few more hundred $$$ :(

Cheers,
Tom

IJ.,

I will miss you. Thank you for sharing, if only for awhile.

Best regards,
Rick

All the photos from IJs retrofit can be found here: http://grid.zerofiveone.com/cnc/ij/

I will post up a description of what he did, and how he did it when I have a little more time.

Cheers,
Tom

The problem with restoring this thread is that I dont think any backups of the forum db are available. Added to that the forum at the time was enforcing a deny rule on any search engines taking a copy of the site (eg google, archive.com).

The latter has now been resolved, Im not sure about the backups.

Admin, if you need an external site to send a backup of your forumdb I can provide you with 2gb of space, and a 800KB/s uplink so you can send those backups somewhere safe. I think this would give you a 10-20day archive of your forum in case you need to restore that elusive thread :)

Cheers,
Tom

You know that every post as a icon (upper right, next to the post #) for alerting a bad post, he had the opportunity to press the button and complain if he was being attacked.

Well I think a good idea would be to remove this thread completely, and perhaps start again with a single message containg everything relavent.

For now unban IJ's IP and see what happens, if he doesnt come back or I get the log then thats the end of that and this thread is worthless anyway.

Cheers,
Tom

Ian has not emailed me but I have un-banned him the door is open.

3 years on and the machine is still going strong only downtime was from the single phase 240v motor bursting into flames on a semi regular basis....

http://members.optushome.com.au/cougarmod/CNC40t.jpg (http://members.optushome.com.au/cougarmod/CNC40.jpg)

Since this pic it's grown a VFD and a 3hp 3 phase motor.

It might be an idea to remove this thread Paul..

IJ!!! You are back! :)

Thats one nice looking mill!!!!
Looks like you are running steppers with encoders, right? Are you using Mach3?

Sven: LOL yep ;)

Dennis: They're servos and I use DeskCNC.

http://members.optushome.com.au/uber-2/vfdt.jpg (http://members.optushome.com.au/uber-2/vfd.jpg)

now that is a big'un in the garage. It's lovely and i bet i could play for hours, but what do you make with it IJ?


p.s. funny how Australian sheds and garages are single-skinned and uninsulated - nothing like a wee drop of condensation around the wiring.

it's 7.53 a.m. and damn freezing in Tassy, i'm going back to bed. :)

Its too bad the majority of this thread was deleted, as it was showed the downside of trying to CNC the Knee, subsequently the quill was made the Z due to the inherent problems of a Z axis knee.
Al.

Bon jour young Al i am a newcomer with little or no knowledge and less experience, no workshop and disabled with a work history that has nothing to do with practical things as a result i am sure you understood what you said but i didn't.

Still, i won't let that stop me, hey? :-)

What I was aluding to was the often failed attempts to make the Knee (Knee Mill) the Z axis instead of the Quill, the quill is the vertical machining mechanism that is normally used to move the tool in the vertical direction, the knee is usually used to just move the table up and down in the vertical direction closer or farther from the quill to accomodate the work piece.
However due to the knee having considerable weight it is much harder to make this a machining axis instead of the quill, when converting to CNC.
Al.

I converted the "knee" to motorized, but monoter with a DRO for precise position. The 6" quill is positioned by the program..When I see a need to increase(or decrease ),just program in a pause, usually 60 seconds.It works if I'm alert.

I have saved the 4th axis for a rotary table ( horz.& vert.) with a servo.


Adobe (old as dirt)

I have an Excello with motorized - counter balanced knee and Z quill.
I just program in a M0 and a message text if it requires a knee change in the prog. Just push start button to continue.
Al.

Al: Yep sorry about that......

I ended up putting the old x axis powerfeed on the Knee so I don't have to crank it for height changes.

Tas: I make small production runs of parts as a hobby it keeps me off the streets ;)

http://members.optushome.com.au/cougarmod/106t.jpg (http://members.optushome.com.au/cougarmod/106.jpg)

http://members.optushome.com.au/cougarmod/109t.jpg (http://members.optushome.com.au/cougarmod/109.jpg)