PDA

View Full Version : Started to build my plasma table.



Apples
06-29-2004, 02:10 AM
I have started to build my plasma table. I have used 65x65x2.5mm galvanised s.h.s. The size of the table is 3.5meters x 2meters. It is huge! It will be able to cut a full sized sheet of material, which is 3mx1.5m.

I will take some photo's and post them up. The basic frame has just about been completed. I have 6 castor wheels on it to move it around, four of which are in the corners and are locking wheels.

ynneb
06-29-2004, 02:15 AM
I can hardy wait for the pictures.

InventIt
06-29-2004, 08:45 AM
Yeh, lets see some pics!!!

Apples
06-30-2004, 02:46 AM
Here are some pics of the table.

3500x2000x900mm.

Apples
06-30-2004, 02:51 AM
how do i upload a pic?

i just went to browse and select the pic and submit reply and thats all that happened.

InventIt
06-30-2004, 09:20 AM
is your pic file too big? Try it again.

Apples
07-01-2004, 04:18 AM
here is a pic

svenakela
07-01-2004, 05:07 AM
I like your welding helmet. :)

-Sven

ynneb
07-01-2004, 05:52 AM
I dont know how plasma cutters work. But I was wondering if there was going to be a problem with cutting through those cross beams. Would it be an idea to have strips of steel in turned sideways in the middle. If you had slots at each end you could replace the strips as needed.

Maybe plasma cutting isnt like oxy cutting!

InventIt
07-01-2004, 09:12 AM
WOW! That's a Monster! Looks good.

IJ.
07-01-2004, 06:48 PM
Originally posted by Apples
It is huge!
Understatement Apples :D!

Well done so far I'll follow this one with interest.
(said it before and I'll say it yet again I really admire you guys that scratch build a machine as my recent retrofit has been an enormous amount of work/thought to complete)

Apples
07-02-2004, 01:57 AM
i am going to have 4 lengths of angle iron welded onto those cross braces and then every 2inches or so cut a slot into the angle and insert some flat steel. The flat steel i will use would have to be around 75mm or 3" wide. that means that i should have 75mm of clearance between the bottom of my sheet of steel that i am cutting and those cross braces. Hopefully this is enough clearance.

Yeah that is a pretty awesome looking welding helmet, it is an automatic darkening one too.!

Apples
07-19-2004, 03:12 AM
Here is a new photo of my plasma table.
Since the last photo, I have grinded back all the welds and painted the frame with one coat of charcoal hammerite paint.

She is slowly coming along.

Still deciding whether to use linear bearings with shafts and pillow block supports. Or to use the 'dual-l-vee' / bishop wise carver bearings.

What are everyone's opinions.

Apples :cheers:

DSL PWR
08-27-2004, 08:56 PM
How are things going? I've looked at the dual vee specs, and I think they may be overkill for a plasma table. But if you used them, you would have a killer router!

Alex S.A
08-28-2004, 10:01 AM
Hi everyone.
Apples,
What you're still deciding is about the way you will make the support to put the sheet to be cut on the table?

Apples
08-29-2004, 12:25 AM
Going to use angle iron to support the sheets of steel. Building has stopped now as i have to fininsh putting up the front fence, retaining wall, lay the turf etc. etc. , Give me a couple months for further progress.

Apples

DSL PWR
08-29-2004, 11:18 AM
I know how that goes, I'm currently building a shed, so a converted mill and plasma table will have to wait.

ynneb
08-29-2004, 06:07 PM
Going to use angle iron to support the sheets of steel. Building has stopped now as i have to fininsh putting up the front fence, retaining wall, lay the turf etc. etc. , Give me a couple months for further progress.

I know how that goes, I'm currently building a shed, so a converted mill and plasma table will have to wait.

The other way to look at it, is finish the machine, and the money you make from using your machine can go into paying someone else to do those other jobs.
My option leaves you with a working machine and a built fence etc, as opposed to a unfinished machine and a built fence in a similar amount of time.

DSL PWR
08-29-2004, 07:04 PM
I need something to put the mill amd plasma in! And the cost of the shed has broke the bank. BTW it's a 12 x 30 garden shed with a 8.5' x 10' bi-fold door.

Apples
08-31-2004, 01:40 AM
The only reason that i am making this plasma table, or the main reason is to make money from it. I hope to cut out parts for fabrication shops.

I am a bit skeptical at the moment. Just wondering if it is worth building?Especially if i can't make money from it.

I just hope that i can make money from it, otherwise i am down $15,000.

Maybe i should just buy a bobcat and a small truck and get into that? What are everones thoughts?

Cheers Apples

DSL PWR
08-31-2004, 02:10 AM
Running a bobcat will get borrrrrring. That type of work is typically seasonal. If you can get a few steady part runs, you'll be busy year round. I take it you have approched some mfg outfits to see if they will contract you? If not well...

Johnuk
11-09-2004, 10:12 AM
Roughly how much did all the steel come to? It looks excellent, but it looks quite expensive.

I'm at the frame stage with mine and am thinking about which way I should go.

Best wishes,
John

InventIt
11-09-2004, 05:07 PM
Well, if you decide not to finish it, you could stand it upright and make one heck of a shelving unit out of it :)
Seriously though, it's looking good. Finish building it. If you don't use it after it's built you could always sell it.

Apples
11-10-2004, 04:25 PM
Yeah i have been so busy working in the garden putting up the front fence that i havent had much time and money. I have just got up my new shed, 6x9 (20'x30). So thats where she will go. I have been thinking of using angle iron with those dual-l-vee bearings to run the gantry up and down. This should be good enough shouldn't it?

shockwatch
01-12-2005, 04:29 PM
Hi Apples. What are you considering using for the rails?

Apples
02-25-2005, 10:45 PM
So far the steel frame has cost me $650 AUD. I have saved up some cash and I am now ready to get some linear motion things happening.

I intend to use those abec7 skate bearings. I am thinking of running them on a pipe, with the bearings spaced out at 120degrees each.

What kind of pipe should I use? Will aluminium pipe be okay? or should i use mild as it might last longer and not wear as much?

Ideas please...........

Apples
03-13-2005, 12:38 AM
Hi all.

Well it has been a while since I have last worked on my plasma table. I am trying to think through a small problem, any help is appreciated.

As you can see in the photo's below, I have two bits of angle iron with a round bar just sitting on top of it. The angle on the outside was just tack welded on, so the other angle and round are just sitting there. In another photo you can see that I have drilled and tapped a bolt in the round bar. A total of five bolts have been tapped into this bar. Here is my problem.

Originaly I had planned on having the angle iron spaced apart by the thickness of a length of 13mmx13mm box sandwiched between the angle. Then the round bar would sit on top. The bolts that have been tapped would hang down between the angle. Then the box would have to have holes drilled so the bolts that hang down off the bar could pass through the box. The bolts could then be inserted through the box and upwards into the bar to tighten and hold it all togeher.

The problems that I see with this are:

1. I might have a problem with tightening the bar evenly and this might cause the bar to flex.
2. The bar will sit lower because the angle is further apart. This means that I might not be able to have three bearing spaced evenly apart. The two bottom bearings would prevent the carrage/truck from lifting up.

What I would like to do now is to just tack weld the round bar onto the angle like how it is sitting in the photo. This is quick and easy and becasue the angle is butted together this allows the round to sit up higher giving access to allow three bearing to be evenly spaced at 120* apart.

Will the heat fromn welding the precision ground bar (20mm +- 0.013mm) affect the accuracy of the rail? Will this be much to worry about as it is only a plasma table not a router/mill.

You thoughts please.

Cheers, Apples

Peter, Queensland , Australia

ajwaverider
03-14-2005, 11:14 PM
I would try another way to mount the round bar to the angle other than welding.The heat just from tacking could cause the bar to warp and ruin accuracy. Im not sure how well the angle is formed at the ends,usaully the 90 degree angle is pretty straight
but the ends are a out of shape. After you get it setup how will you make ajustments if needed?

vladdy
03-15-2005, 01:18 AM
One way to get 'some' accuracy in the welding of the round bar to the double angle iron would be to use a spacer in between the angles, slightly lower than the bar so it doesn't interfere, in this way the bar will be held between the two straight edges in sort of a 'cradle' thing-a-ma-jig

the pieces have to held quite tightly when welding to reduce any possiblity of 'permanent' distortion....:)

If all you are doing is plasma, there 'shouldn't' be any upward load, so two sets of bearings on top may be all you need, but then it wouln't be very suitable if you decided to convert it to a router or other type of 'contact' maching.. the bat could even be skip welded to the angle irons, no tie down bolts would be needed..

drawback is very little adjustablilty for that 'oops' factor..

quick example..

Apples
03-15-2005, 04:41 AM
Vladdy,

That drawing of yours is exactaly what I originaly had in mind. The spacer material in the middle that I was going to use was 13mmbox. That way I could bolt the round to the spacer box. Problem is though that the head of the bolt is to large, and I would not fit a socket onto it to tighten it up. So..
Now I plan on having a stud, or in my case it is only a bit of threaded rod which is going to be threaded into the round and then be used as a spacer and hang down and go through the steel box frame of the actual table. Then from underneath I can bolt it up with plenty of room to tighten things up.


Peter

Hasher
03-17-2005, 05:55 AM
Hi Apples

For another idea how to make your X axis take a look at this webpage .

http://www.frontiernet.net/~salterc/cnc.htm
http://www.frontiernet.net/~salterc/slidebearings.jpg

I am looking at making mine with a group of "box transfers" but I am building a Router not plasma table

Project looks great so far !


Paul

Apples
03-27-2005, 06:43 PM
I have put my bearings and rails on and can move left, right forwards and backwards!

I will take some photo's this afternoon when the camera comes home. .

Apples
03-27-2005, 10:54 PM
The rails a precison ground mild steel that are supported by 40x40x4mm angle.

Both the the long and short gantry's slide very easily up and down the length of the table. I was sitting on it before and was able to "push" myself along very easy. With one push I would just keep rolling along..........AWESOME!

It slides nice and smooth without bumps or wobbles...WHHOOOOO!

The precison ground rods and angle iron have not yet been bolted down. I have to straighten one side. How is the best way to do this? I think that the way to go would be to stretch out a lenght of mig wire and pullit really tight with a turnbuckle or somthing. Then measure the gap between the mig wire and the precision ground shaft with feeler gauges.

To adjust the gap maybe I could tap some bolts or weld some nuts onto the angle iron and rig up somthing so that I can just turn a nut and the angle iron slides in or out for adjustment. Hey maybe I don't need to go that far as such. I could probably just bolt the angle down lightly and then adjust with a hammer/block of wood for straightness against the mig wire. Then once it is straight I could tighten up the bolts and nuts.


Let me know what you all think, she is really starting to come together now. YES YES YES!

ajwaverider
04-06-2005, 12:39 AM
Hey Apples!Nice to see some more of your progress.How did you end up fiting the rails to the angle?

Apples
04-13-2005, 07:01 AM
as of yet the rails are not bolted down. I have decided to get the rack and pinion and motors all going first just to see how it all goes. Then i will adjust the rails for straightness and bolt them down etc.

CanopyFx
05-08-2005, 09:49 PM
Apples
Do you have any drawings on how you are going to mount the Rack and Pinion? I am building a similar table and would liek to see your ideas for the drive system

Joe

dgalaxy
05-11-2005, 09:34 PM
i was wondering the same thing man that is a awsome table

Apples
05-12-2005, 06:28 AM
Joe

I plan on supporting the rack, by bolting it to some angle iron and then bolting the angle iron to the side of the table. The rack will hang witht the teeth down to stop 'crap' from falling in. Then i will most likley have a direct drive setup from the motor shaft to pinion to rack. The motor will hang on a hinge below the rack. Then I will put a spring up to the carrage/truck, which will slide up and down the table and also support the motor, whilst providing contact for the pinion to the rack.

Hope you know what I mean.


i need help on deciding what hardware and electronics to use. I have some cash now and I might just spend some to get the table going. At this stage I was thinking of just starting off with an oxy setup first while cash is low.

CanopyFx
05-12-2005, 08:42 AM
I am working on a few drawings that use the same idea. The only difference is I am making a timing belt reduction box to allow for a 10:1 gear reduction. I will post some pictures as soon as they are done.

Thanks
Joe

ynneb
05-12-2005, 07:05 PM
The only problem I see with your linear bearing design is that there is nothing to stop the gantry lifting off the rails. I made the same mistake, The ganty will buck when accelerated.

You are doing well though.

Apples
05-13-2005, 12:15 AM
ynneb, I have extended the length of the trucks/carrages on the long length of the table. They are now 1m in length. I have also bolted the gantry that goes left and right to the 1m long carrages that go forwards and backwards. There is a fair bit of weight there so I do not think that this will be a problem, but hey...I'm only new and learning as I go.

ynneb, you also seem to have a bit of experience with the Rutex drives. I am going to use my table with an oxy first to save me spending big dollars on buying a 3phase plasma cutter just yet. I am particularaly interested in the plasma a/b board they have for sale with thc built in. Can I just use this board for oxy now then later on use if for a plama cutter?

What do you think are the bits that I should get to make this thing move? Can you give me some advice on what power supplies to buy, what servo motors to buy and what rutex products to buy?

Anyone else that knows a bit please tell me what you think I should use.

Cheers Peter

ynneb
05-13-2005, 12:34 AM
Wow 1M trucks. I guess that should work. I finished up just putting a bearing under my trucks so as to stop the bucking. ( Ye har ridem cowboy)

I cant see there been a difference with the driver cards for plasma or flame. Best to ask Vlad at Rutex.

I have some bad news for you. The biggest part of your machine is the least expensive part. To build my frame it cost me $700 in steel, and yet, my machine still totaled 3 - 3.5k in the end.
I dont know how belts would preform in a flame/arc environment, so I guess rack and pinion is your only option, other than expensive ball screws. Unless you could hide the belts away from incidental hot splashes.Belts is definately the cheapest option.

What will you need?
You will need timing pulleys, quite a few of them so as to gear down your servos.
Servos, servo driving cards, the mother board for the cards,power supply, obviuosly a computer and driving software, and lots of sundries. The sundries will unexpectantly add quite a bit to the cost of your machine.

I notice you are taking your time with this machine. That will allow you to save up as you go.

I must say, your machine reminds me a lot of mine. Lotsa steel.

Apples
05-13-2005, 01:10 AM
why can't I direct drive servo onto the rack? If i tell the motor to go slow it will go slow right??

Yeah i will use rack and pinion and hopefully be right to drive on just on side. A 2m length of rack is about $100 i think.

ynneb
05-13-2005, 02:22 AM
Well you can direct drive, its just that you lose resolution/acceleration/decelleration.
I guess the feed rate of plasma/flame is quite slow. You should be alright. I must say its a bit of a guess though. The other thing is you will only be using about a 10th of the servos speed without gearing down. If you gear down you will get much better arcs (circles) etc.
You will get a much snappier machine gearing down.
I have geared down 3:1 and wish I could have geared more. I still may in the future.

For a machine the size of yours I truelly think you will regret not gearing down a bit.

Apples
05-13-2005, 03:31 AM
I can remember some sort of calculation to work out the reduction gearing. What is it do you remember. Can you show me a photo of your motors with the reduction setup please. Have you just used a steel lined rubber belt, with teeth that grip onto a cog/gear wheel etc. I want the table to whizz up and down pretty quick. So reduction sounds like the way to go.

Can I use a duel drive setup with the rutex boards?

Peter

ynneb
05-13-2005, 05:24 AM
See if you can decypher the pictures mid way into this thread.
http://www.cnczone.com/forums/showthread.php?t=6143

I didnt do dual drive, i just had a drive shaft through the ganty driving both sides.
It is cheaper, easier, requires just one servo, has less potential to have racking problems, and works extremely well. Remember my ganty is 2m wide, probably similar to yours.

Apples
08-14-2005, 06:59 AM
Hi all,

Well I am finally slowly getting there. I have bought a 1200oz-in stepper for the long axis. That axis will weigh about 110lbs or 50kg when the gear rack goes on. The shorter axis is powered by a 270oz-in stepper motor.

Both of these motors will be run via Gecko G202 drives. I have them already.

The gear rack and pinion should arrive late this week. Bought off of T.E.A. Transmissions from Brisbane, Australia. If anyone in Oz interested.

I have breakout board, saftey charge pump, and mini power supply on order from cnc4pc.com. Hopefully they get here end of this week, if not they should be here buy next week.

Yeah so all is coming along good. I just need a power source, I have seen the thread about using a microwave oven for a power supply. I have one here, so maybe I can use that, not to sure though, see what happens.

So basically when the gear rack,pinion and the breakout boards arrive, I can set them all up. Get myself a power supply and then I can test the table to see if it will actually move. If it does, I will be able to breath a sigh of relief..

The plan is to get it to the stage of whereI can make it move via the computer. Test it all out, and check for square. I'm really not looking forward to getting it all square. I think it is going to be a bit of stuffing around. The gantry is just bolted at the moment, as it will allow for me to adjust if for square latter on.

So that's where I am at.

GOTTA GET ME SOME POWER..................................

Cheers

:cheers: Apples

DanOSB
08-16-2005, 11:17 PM
i would be bit concerned about spring.. if u are moving back n forth it might loose its accuracy.. the pinion coming out of rack and skip or something like that...

im planning on running 1200 oz/in motor for x/y axis myself.. overkill hopefully.. but keep up with your progress u are lot more far ahead than me.. i need to catch up :)

Good JOB!

Apples
08-17-2005, 12:08 AM
Yeah I will just see how the spring idea works. If it is no good I will have to permantly fix the motor.

Any ideas on where I can get a 50v 15amp power supply from?

Cheers

Apples

DSL PWR
08-17-2005, 01:47 AM
Most industrial machines have a spring on the motors. Any that I have seen have a compression spring.

DSL PWR

DanOSB
08-17-2005, 09:13 AM
oh thats good news for ya apples :) and for power supply i have no idea.. i was tryin to find some turnkey power supply from ebay or something... no luck.. might buy some from someone who builds the stuff or something..

ynneb
08-19-2005, 01:26 AM
Nice job Peter (apples), You machine is really starting to take shape.
I am considering to change my machine to dual head. One for router work and the other for plasma. I will watch your progress with interest.

What sort of things are you planing to use your machine for ?
All I can think of is making more machine parts, and super heavy duty car ramps :)

Apples
08-19-2005, 04:23 AM
I am going to hopefully make a few steel signs and odd jobs. I have had different quotes for power supplies. Ranging from $1500, $550 for 50vdc@15amps, $800 for 42VDC@20amps and 42VDC@10amps for $400.

Think i might order from overseas or ebay one, or even make one. I was only hoping to spend about $200.

CJL5585
08-19-2005, 04:46 AM
I am going to hopefully make a few steel signs and odd jobs. I have had different quotes for power supplies. Ranging from $1500, $550 for 50vdc@15amps, $800 for 42VDC@20amps and 42VDC@10amps for $400.

Think i might order from overseas or ebay one, or even make one. I was only hoping to spend about $200.

Buy 2 of these for $70.00 + 1 large capacitor and your power supply problem is solved. Wire them in parallel. You will never max them out with one 1200 in/oz motor and one 250 in/oz unit.

http://cgi.ebay.com/Vicor-FlatPAC-48V-Power-Supply-New-In-Box_W0QQitemZ7539380689QQcategoryZ36323QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Jerry

EDIT: Just noticed he sells to US only. But these will do the trick. You might be able to get him to ship them to you since Australia is a LOYAL and FRIENDLY country to the US>

Apples
08-19-2005, 06:10 AM
Thanks heaps for that eBay link. Have you used these before? How did you know about them?

I have sent them an email to ask for postage to Australia, hope they will post them.

What size capacitor do i need?
Also these will have to be bolted into a box so that the terminal are not exposed?

Thanks again for that Jerry.

Cheers

CJL5585
08-19-2005, 10:14 AM
Thanks heaps for that eBay link. Have you used these before? How did you know about them?

I have sent them an email to ask for postage to Australia, hope they will post them.

What size capacitor do i need?
Also these will have to be bolted into a box so that the terminal are not exposed?

Thanks again for that Jerry.

Cheers

I am using this power supply in my CNC Control box. It is powering 3 each 200 in/oz steppers and does not even get warm. I could possibly run 2 more off it before causing it to warm up.

Don't worry about the terminals. A kit is included with the supply that contains copper bolts, nuts, washers, and molded plastic covers that insulate the terminals.

The unit has threaded holes ( 8/32 ) in the supply bottom. One just drills holes in the chassis to match the supply, sticks some screws through and tightens them up, attaches the line, neutral, and ground on the input side, and adds a wire for the + and - outputs. There are lots of other terminals, but don't use them, otherwise you will be bewildered.

On my unit using this supply, I used a 15,000 uF capacitor rated at 100 Volts DC.

I would recommend in hindsite, mounting the unit to a side wall of the enclosure to keep any particles of dust, metal, out of the unit.

I used Vicor products years ago in some major instrumentation systems. The units worked for years without problems. When I saw them on e-bay and I was building a CNC, I purchased several of them. There are some CNC control boxes in Florida and Utah operating with these supplies other than my own.

Hope this helps.
Jerry

CJL5585
08-19-2005, 11:01 AM
Peter,
Check your private mail.

Jerry

Apples
08-23-2005, 07:44 AM
I have received my rack and pinion from T.E.A. Transmissions. They arrived well packaged on a piece of 1"x3" lump of timber, so as to stop them getting bent.

ynneb
08-23-2005, 09:57 AM
What was the cost of your rack and pinion ?
How much backlash do they say it has ?

Apples
08-27-2005, 07:08 AM
Well I have had the pinions machined to fit on the motor shafts.

I have put the pinions on and welded the rack to the table, and put the springs on to hold the motors up to the rack.

My breakout board should arrive wed-thurs this week. The power supplys should get here by friday this week coming I hope.

All I need now is to buy a capacitor, and buy some wire to hook everything up.



What kind of wire should I use for the power supply. What size for hooking up the capacitors, and wiring the power supplies in parrallell?

Also what kind of wire to use that goes from the gecko's to the steppers. These will be pretty long lenghts of wire. I understand that these have to be sheilded wire????? If they have to be sheilded wire, what kind of sheilding do they need and what sixe wire should i use?

Cheers Peter

Not much to go to see if it will actually move, VERY excited :banana:

CJL5585
08-27-2005, 08:32 AM
What kind of wire should I use for the power supply. What size for hooking up the capacitors, and wiring the power supplies in parrallell?

Also what kind of wire to use that goes from the gecko's to the steppers. These will be pretty long lenghts of wire. I understand that these have to be sheilded wire????? If they have to be sheilded wire, what kind of sheilding do they need and what sixe wire should i use?
----------------------------------------------

The input (or line side) should be wired with at least # 16 wire. It should also be fused.

The wire from the Gecko's to the motors is NOT required to be shielded, but shielded is better. This wire should be the same size that is on the steppers. It is probably #18 or #20 gauge wire. If you use shielded wire, Connect the shield ONLY ON ONE END to chassis ground.

As for the Power Supply + and - wires: It should be #14 gauge wire. Run the + and - wire from the supplies, to the capacitor, to a common stud terminal for each side of the supply. From the common stud + install a 5 Amp fuse and then run a wire # 18 to the + line on the Gecko. Run a seperate wire for each + and - line. DO NOT loop the power for the drives togather. Make sure you have a capacitor across the Gecko + and - terminals rated at least 65 VDC.

For the breakout board:
Run a +5 Volt seperate line to each Gecko.
The - 5 Volt (common) goes to terminals 18 thru 25 on the breakout board.
The step and direction wires from the breakout board goes directly to the Gecko's. (I ran seperate wires for each of the step and direction lines, so as not to permit induction from the step signal into the direction line)

Hope this helps
Jerry

Apples
08-31-2005, 01:31 AM
Well I now have everthing ready to go.

Just have to hook everything up.

CJL5585
08-31-2005, 02:17 AM
Peter,
Looks like you are ready to do some work. Everything is looking good.

Jerry

Apples
09-08-2005, 03:20 AM
Hi all,

I have a video of my plasma table moving for the first time.

It is drawing out "Road Runner" that comes with Mach3.

Not to sure how fast it is going. How fast does everyone think that it is going? I'd like to know myself.


Any questions just email me.

Here is the link. Thanks go to Ynneb for uploading it to the zone.

http://www.cnczone.com/modules.php?name=Downloads&file=viewfile&id=56


apalais@supernerd.com.au

Peter

Apples
09-08-2005, 03:22 AM
Here is a pic of the Road Runner.

Scott V
09-26-2005, 02:27 AM
Looks like it will be fast enough for about any plasma job.
The speed is kind of hard to judge, but looks like you will
be happy with it.

Scott

Apples
10-09-2005, 07:03 AM
Well,

Since the first run of the plasma table I have noticed some design flaws and have therefore taken corrective action.
I no longer have the angle iron gantry setup. This was just to flimsy and it was also wobbly. I have now decided on making myself a tough rigid gantry out of box steel. This should be much much stronger than the dodgy angle iron. I will be using Bishop Wisecarver bearings(number 2 size) and the matching track, which is hardend and ground.

Checkout the photo's. This gantry is actualy about 10kg lighter than the angle iron setup. So there you go, it is stronger, will be eaiser to mount the cutting torch to and it also looks more astheticaly pleasing, and slightly professional.

I have since ordered another Geckodrive and another 1200 oz-in stepper. I really think that I am going to slave one motor off the other and drive it that way. I have heard mixed responsed to this argeumentative topic. Some say the only way is to use a driveshaft or a jackshaft. Where as some people say that they have never had trouble using the slave way. So this is where I am at the moment. I really havent got that far to go now. My Bishop Wisecarver vee bearings and track should arrive either tomorrow or tuesday. The THC should get here this coming week as well. And I am just about to order myself a Hypertherm Powermax 1000 with the machine torch.

So I will let everyone know how it all goes.

Cheers,

Apples (Peter)
Australia

ger21
10-09-2005, 09:36 AM
I've never heard anyone say they had a problem with Mach3's slaving feature. Just remember you'll need to modify the homing button macro so the slaved axis homes with the master. I don't remember how to do it offhand, but I saw it on the Yahoo group.

If you use a shaft between the two sides, it should be driven by one motor only. Two motors mechanically joined together will all be fighting each other as they will usually be misaligned a very small amount.

DSL PWR
10-09-2005, 11:52 AM
3mm tube wall should be thick enough to hold a thread, so just drill and tap holes for the rail. If you insist on using sheet metal screws DO NOT use the self tapping type, as they make a big hole with little thread contact. Get the pointed type and drill a pilot hole. It will take a couple trys (in a scrap piece) to get the smallest possible pilot hole that you can drive the screw thru without it breaking. Remember you don't need to get the screw thru in one pass, just rock it back and forth like a tap.

Now that I think about it don't the wisecarver rails require a stand off? If they do get some square stock (20-25mm) drill and tap holes in it to match the rails and weld it on to the 75mm tube.

Metalfab_101
10-13-2005, 06:25 AM
Hey Pete, got an update for us? I hope these storms haven't given you too much curry out there!

Cheers,

Damo.

Apples
10-13-2005, 06:42 AM
Metalfab_101,

Unfortunatly we havent go anything much out of these storms. They seem to come at us then hit the Toowoomba range and go around. How about you?

Go to www.bom.gov.au it is the beauro of meterology website. You can select from a variety of radar sites and they will show you where the clouds and rain are.

There are no updates at the moment, all that I am doing now is drilling the holes that will be used to screw the bishop wisevcarver track on.

DSL PWR

I have actualy allready bought some self tapping screws. I might try one or two and see how they go. If they are no go I will buy the ones with just the point. I really do not want to go and tap all those holes, but if in the end I have to, well I have to.

You mentioned a stand off. I have not heard of this before. When the rail is sitting in place, it looks and feels pretty good.

Peter

Apples
10-23-2005, 07:56 AM
Here's how things are coming along with my gantry.

The vee bearings work good. nice and smooth! those steel plates at the end have absolutly no twist at all. See how it goes when she is all bolted together.

I was just checking the height for the gantry beam. That is why the box and clamp is there.

Peter
Australia

Metalfab_101
10-24-2005, 12:33 AM
Here's how things are coming along with my gantry.

The vee bearings work good. nice and smooth! those steel plates at the end have absolutly no twist at all. See how it goes when she is all bolted together.

I was just checking the height for the gantry beam. That is why the box and clamp is there.

Peter
Australia

It's coming along Pete. I bet you'll be happy with those v-bearings, they look the goods.

How did you end up adjusting them for height, using the shaft in an eccentric housing?

Cheers,

Damo.

Apples
11-03-2005, 06:51 AM
Hi all,

Here are some more update photo's of my plasma table.

Apples

Metalfab_101
11-03-2005, 04:25 PM
Getting closer Pete. And DAYUM that's big b!tch :rainfro: :eek:

How's the gantry now, have you sorted those flexing issues?

Cheers

Damo.

Apples
11-21-2005, 06:08 AM
Damo,

I have not yet had the gantry moving with the motors yet, so I do not know what the flex is like. I am having 2 motors for the long axis. They will be direct drive straight onto the rack. Hope fully this will be okay, otherwise I will have to reduce it down with belts. I really do not want to as this will be more stuffing around. I just want to get in and start cutting things.

This is what I am up to now with handing the motors.

Cheers all,

Peter

Metalfab_101
11-21-2005, 12:13 PM
Damo,

I have not yet had the gantry moving with the motors yet, so I do not know what the flex is like. I am having 2 motors for the long axis. They will be direct drive straight onto the rack. Hope fully this will be okay, otherwise I will have to reduce it down with belts. I really do not want to as this will be more stuffing around. I just want to get in and start cutting things.

This is what I am up to now with handing the motors.

Cheers all,

Peter

You must have been busy lately Pete! Haven't heard much from you.

How long til you're cuttin' you reckon?

Apples
11-21-2005, 02:04 PM
Damo,

I should have 3 phase power on in two weeks. By that time I should have it all running again, although I do not know if I will have the THC going by then.

How are you going with you cutting machine?

Peter

Metalfab_101
11-21-2005, 08:16 PM
Damo,

I should have 3 phase power on in two weeks. By that time I should have it all running again, although I do not know if I will have the THC going by then.

How are you going with you cutting machine?

Peter

Haven't even started mine yet. Still gaining knowledge and collecting info while I build my shed. Once that's done I can start collecting parts :) which will be around April I guess.

:idea: If your setup is going to be able to cut 12mm i'll throw a job your way once it's up and running. I have a tube bender project happening that I need bits cut for at some stage.

Damo.

Apples
11-22-2005, 05:58 AM
Damo,

I have a hypertherm powermax 1000 with the machine torch for the cutting table. I can cut anywhere on the sheet of steel up to 10mm. Anything else I have to do an edge start or drill a hole. If I do an edge start hypertherm have a reccomended cut capacity of 19mm, with a maximum of 25mm.

I think that if I end up cutting much steel over 1/2" or 12.5mm I will rig up an oxy. This has a straight cut regardless of the thickness of the steel being cut.

Cheers

Peter

Metalfab_101
11-22-2005, 12:17 PM
Damo,

I have a hypertherm powermax 1000 with the machine torch for the cutting table. I can cut anywhere on the sheet of steel up to 10mm. Anything else I have to do an edge start or drill a hole. If I do an edge start hypertherm have a reccomended cut capacity of 19mm, with a maximum of 25mm.

I think that if I end up cutting much steel over 1/2" or 12.5mm I will rig up an oxy. This has a straight cut regardless of the thickness of the steel being cut.

Cheers

Peter

I bet the Hypertherm cost you a packet!

Sorry if this is a bit OT but I have been trying to track down a machine torch for my oxy/acet setup. Any idea where I can get one from without having to sell one of my kidneys???

Damo.

Brian Kidd
11-22-2005, 03:40 PM
I bet the Hypertherm cost you a packet!

Sorry if this is a bit OT but I have been trying to track down a machine torch for my oxy/acet setup. Any idea where I can get one from without having to sell one of my kidneys???

Damo.


Tell me about it. I was looking into getting a machine torch for my brothers ESAB Plasma thinking it would be $300-$400 but they want $1000+ for an ESAB and about $800.00 for a Thermal Dynamics one that would fit the ESAB :eek:. Hell he only paid about $2000 for the whole machine. Guess I am going to just design the CNC Table to hold the regurlar hand torch.

B.Kidd

whateg01
11-22-2005, 04:02 PM
This, too, may be a bit off topic. Maybe a new thread is in order, but why are machine torches so expensive?

From what I know, which isn't much, the fundamental difference is the way the gas is controlled. I believe the straight tip is fairly minor, and maybe somebody makes a straight tip that will attach to a hand-held. On that note, does anybody know of a manufacturer why makes a straight tip for a hand-held Victor type torch?

Dave

DanOSB
11-22-2005, 08:21 PM
get 180 degree head torch on ebay.. i got mine for 100 or less

and then what im going to do is simlar to http://www.cnconabudget.com/torch.html

but not using regular hand torch since it would be bulky.. rather it straight up

there is picture of that torch but thats bad one but im sure u get the idea

Apples
11-26-2005, 05:33 PM
Hi all,

I have to say, thanks for all the help so far.

I am in need of some help to finish of the machine. All the details can be found here.

http://plasmatable.bravehost.com/

Cheers

Peter
(Australia)

whateg01
11-27-2005, 12:01 AM
Peter,

Thanks for all the photos! I enjoy watching these projects progress. (It's good to know that somebody is making progress.)

Forgive my ignorance, but I was wondering why the slats in the table top are woven through the supports instead of being straight?

Dave

DSL PWR
11-27-2005, 11:04 AM
If the slats are straight and you cut a straight line directly over one, you weld your work to the slat.

whateg01
11-27-2005, 10:32 PM
Thanks. I knew there was a reason.

Dave

whateg01
11-27-2005, 10:52 PM
Hey, what if you needed to cut out an ocean scene with gentle waves that matched your slats? LOL :rolleyes: :D :wave:

Dave

Apples
11-28-2005, 06:47 AM
Well I have tried to upload 4 movies to my site. To better help explain the low speed noise. I have a fast one there at 2000ipm or 50,800mm/min, making a circle.

Unfortunatly I have to pay money to upload movie files to this site. So If anyone was interested in the videos see what you want and I can email them to you.

Cheers

Peter

P.s. Bought some bearings today to make belt reduction setup!

Have top order timing belts and pullys now.

Cheers

Peter
(Australia)

whateg01
11-28-2005, 09:46 AM
Peter, I would definitely be interested in videos you have. It helps to give me ideas for my design. Looking back through some of your previous posts, it looks like you went through several revisions on your gantry. Interesting to watch the progress.

Dave
whateg02@yahoo.com

Apples
12-18-2005, 05:51 AM
Well well well,

I made a timing belt reduction. I used 28 tooth and a 72 tooth pulleys which gave me about 2:57 to 1 reduction.

This made a slight difference to the vibrations/resonance that I was getting.


Found out that with the Gecko's there is a 'low speed trimpot screw'. Basically all you do is run the machine then turn the screw untill the thing goes quiet.
The screw is located at the back of the gecko, opposite where all the wires hook up.



I have also done my fist cut/s with the setup.

I have only just been using the remote starting pendant that you turn on with the flick of a switch.

Cuts are very slaggy underneath. I just wanted to see if anything would happen with the plasma setup.

Now I have to work out how to hook up the remote start to the breakout boad and turn it on via the computer.

Apples

Peter
Australia

Weldtutor
12-18-2005, 09:15 AM
Peter
Congratulations!!!
It must feel great to make those first cuts after several months of work.
When you get to faster travel speeds the slag may be reduced.
WT

DSL PWR
12-18-2005, 11:52 AM
Make sure the air pressure is set on the high side, crank up the current, make sure the torch is square, and go faster. If your torch is on the small side for the material: get a bigger torch, cut thinner material, or live with the slag.

Apples
12-19-2005, 05:28 AM
Done some more testing in the shed.

I was cutting those parts at 40 amps. So I wound it up the the maximum of 60amps and upped the feed speed. These new cuts came out pretty good.

When it turns a corner the corner is not very sharp, like the torch needs to stop ther for say 1/4 of a second.

Is this possible to program into Mach3?

Peter

ty1295
12-19-2005, 02:46 PM
G4 is a dwell command. You can spec how ever long you want it to pause.

You will need to research what letter Mach needs with the G4, some machines use F, etc. I forget what Mach uses.

Apples
01-29-2006, 05:37 AM
Well it has been a while since I last posted.

Here is an update.

I need to find a way of supporting the wires that go to the motors. I think that I could just hang them from the roof and let them dangle down. I might have to make somthing up though.

Any ideas?

Cheers

Peter

Weldtutor
01-29-2006, 10:05 AM
Peter
To support your cables one method would be a post about 4 ft up from a corner of the table (or centre of one side) with an arm from top of post extending over the middle of the table.
Wires could hang from the end of the arm.
Nice photo of the bracket in the hand.

Apples
01-29-2006, 02:10 PM
Weldtutor,

I have thought about ways of doing it, and that way probably seems the best way to do it. Like when you go to "Carlovers" and was your car by hand. The hoses come down from the roof via an arm. The arm can spin 360.

So I might have to do this, and put a bearing at the piviot point so that the arm can swing left and right a little.

Peter
Australia

Apples
02-03-2006, 05:59 AM
This is 1.5mm gal, steel.

Peter
Australia

Weldtutor
02-03-2006, 06:14 AM
Peter
Mighty fine looking sign.
That should get you some customers!
WT

Metalfab_101
02-06-2006, 05:47 PM
Congrats Pete! Just all the fiddly stuff now eh?

Scott V
02-06-2006, 07:56 PM
Hey Peter,
do you need a litte help keeping the center in your P and other
letters?

Are you using Corel?

I saved a E-mail Tom Caudle sent me from a while back with
that info. Use the trim in Corel to keep the centers.
It's very simple and will help the look of your good looking
sign.

Scott

Apples
02-09-2006, 06:44 AM
Scott,

Yes I have the instructions for the corel trim thing that you have mentioned. I just totaly forgot about it untill it was cutting. It is just a test piece to see what the cut cam out like.

I have bought some 40 amp nozzles, and they really do give a tighter cleaner cut. It is also good because the machine can go slower, and this makes a smoother cut.

I cut out three small signs today about 500mm long. I have really go the *&$%'s about it because each one is a different length.

I wonder If I am loosing and steps. I think that there is a function in the mach3 mill screen that allows you to check for missed steps. Any ideas on how to use this?

Peter
Australia

Apples
02-09-2006, 06:47 AM
Metalfab,

Yeah fiddle stuff now, I have to get the thing square now. I have just had it clamped down really hard with 4 f clamps. I will bolt it this weekend.

I really do not think that I can get this thing to be accurate within 1mm. I was hoping to get it at least that accurate. But that I mean possitioning.


Scott,

How accurate is your table. Practiacal isn't it?

Peter
Australia

Scott V
02-09-2006, 10:29 AM
Peter,

I never really checked on total accuratcy but on small pieces it's very good.
The table is way more accurate then the plasma arc itself. I surprise
myself sometimes in that area. (Good accurate cuts)

I like different tips for different size material but the 40 amp ones
are my overall favorite.(Thermal one torch) Up to about .180 thickness. Thicker then .180 the
edge are like a laser in smoothness but loose too much in the area
of bevel. I step up to the 60 amp nozzles at that point. More lines
in the edge but a much straighter piece. Plasma is all about compromises
and the work arounds. :)

I have not looked at mach 3 for the feature of checking the steps,
I'm sure the Mach 2 forum will help. I have not lost any steps (that I know of) yet, so I have not bothered with finding that info.

Apples
02-12-2006, 06:26 AM
Here are some more photo's of some part that I cut.

These are 5mm steel. They are for a 44 gallon drum that is being made into a camping oven.

They are the ends, the ring is to be welded onto the drum then the other thing is the door that will swing off the ring.

I measured the parts on the top of the steel and they all came in with in 0.6-1.4mm of being right. I think that I can get this a bit better, but I am really happy with that so far. These were actually undersize by that much. I wonder what they would be if I measured them on the underside. The bevel would make them bigger so it would make it a lot close to the correct size. I might have to measure it tomorrow again.

Peter
Australia

Weldtutor
02-12-2006, 11:16 AM
Peter
Nice cuts you are getting now! :) The quality seems to be improving for you.

What material thickness is shown?

Do you know the travel speed and amperage settings used for the items pictured?
Thanks WT

Apples
02-12-2006, 02:13 PM
WT,

That is 5mm steel. Cut with a 40 amp nozzle, with the machine set at 40amps. The cutting speed is 1000mm/min.

The 60 amp nozzles allows you to cut at 3300mm/min, according to the hypertherm manual.

Peter
Australia

Apples
02-13-2006, 02:33 AM
That cicle was to be 533.6mm in diameter. It is a bit hard to measure below 1mm with a tape measure. But I reckon that I can estimate.

I measured on the back of the steel this time.

Anyway the circle is not quite round. The x axis is 533.5mm which is spot on, well out by0.1mm, but how can you really measure thay amount with a tape.

But the y axis is 530.5mm, so that is out by 3.1mm. Looks like I will have to go back out and reset the steps per unit in mach.

Cheers for now,

Peter
Australia

Apples
02-14-2006, 05:51 AM
What is wrong with this picture?

Something happened today on my plasma table. That has really shocked me.
The shaft of my 1200oz-in stepper motor fell off! I can't believe it. Like why?
I mean wouldn't it just have lost steps first???

That is a 1/2" shaft, cleanly snapped off. Would it be because of a dud in a batch of shafts?

Peter
Australia

paulC
02-15-2006, 07:32 PM
You must be gutted.
Is that the x axis?
How was the belt tensioned? If there was too much tension it could have been flexing the shaft until it fatigued and broke.
I would think that it was more likely a faulty shaft but I'm no expert.
Was it a new or second hand stepper?

Paul

Apples
02-16-2006, 12:35 AM
I am a bit surprised rather than dissapointed at the moment. I haven't actually started chasing work at the moment so there was no money lost in that regard.

I am getting a new one sent ASAP. Even the bloke that I bought it off was surprised. "That's one I havent seen before", was his reply.

Looks like it might have just been a dud shaft, who knows, could have had a hairline crack?

Anyway this down time will let me install some home switches. And also give me time to tidy up loose wires.

Peter
Australia

Apples
09-11-2006, 07:26 AM
Hi all. Been a while.

I want to fix up the whole z axis and carrage assembly. I bought a router and have cut a test piece of MDF wood of a clamp/bracket that I will be making out of aluminium.

There is a fair bit of backlash/slop/play in the whole carrage assembly. So I'm going to cut out a new carrage out of probably 15mm thick aluminium.

Here is a pic of the test design of that bracket.

Peter

Apples
09-11-2006, 07:46 AM
Here is a pic of the small router in the machine. You can see all the parts in mild steel that I want to make into a nice tight aluminum carrage.

Peter

Terry G
09-23-2006, 09:44 PM
Apples,

Thanks for all the great pictures and updates of your table. I am in the process of designing and building a much smaller table to use with my Hypertherm 1000.

In one of your earlier posts you mention you were going to use a THC. Did you end up using the THC to cut out out the pieces you posted photos of?

Thanks.

Apples
09-23-2006, 09:57 PM
Hi Terry G,

Yes I have got a THC. I have a THC-300. I need to put in a ballscrew for my Z-Axis and really need to machine up some alum. brackets etc. There is a fair bit of play there at the moment.

Peter
Apples

Terry G
09-23-2006, 10:21 PM
I was also looking at the THC300 today. I read through the manual a couple of times. Though I am not sure if my DeskCNC contoller will support this THC. I already have a complete DeskCNC controller board, driver and servo setup for my CNC mill, and was hoping to use all the same stuff for my plasma table expect for the servos.

This is just a hobby for me, and I never know what I am going to be making next, but up untill now I haven't had the need for anything very large. I am just trying to figure out the drawbacks to not using a THC, and how much acuraccy I would loose.

I will most likely build the table using what I have, and make it so I can add a THC if I am not happy with the results.

Have you cut out pieces with and without the THC on your table? If so what differences did you notice.

Thanks.

Apples
10-01-2006, 08:41 AM
5mm and up in thickness there is no difference. But under 5mm the steel really warps and I don't see how you would cut with out it.

I have cut smaller brackets in 3mm without the THC. But I have also cut 3mm steel where it has buckled and twisted by a very huge amount.

Peter

sanjiv
10-26-2006, 10:53 AM
it is 2006 last., it might have completed or u are making bed for sleeping

sanjiv
10-26-2006, 10:55 AM
what is this, i had posted above message for some one else

cncner
07-27-2008, 01:31 PM
Hi Peter
I am sure your table is working well
I would like to use the same bearing system for my plasma table.
Could you please tell me, roughly, the cost of pinion & rack/meter and vee bearing & track/meter included parts number?
thanks a lot for sharing your experience
Feliciano
Italy

Apples
07-27-2008, 04:41 PM
Hi cncner

I can't remember how much the bits cost. I have sold the table ages ago.

Peter