Hi All
Like many i've been lurcking about for a while trying to learn as much as i could before attacking a cnc project.

Why a 25hr day?? well it takes me soooo long to do things and i've to many hobbies

I started by downloading the jgro plans, I had full intentions of building my machine out of mdf but to my luck work was dumping some extrusion so have decided to use that instead. So now this machine has turned into an all metal affair.

I started by making the gantery, I sort of just work 'on the fly' when it comes to sizes, but I intended to make a machine that would be able to mill parts for model rc aircraft.

I also have got the bearings fitted that will run along my guide rails.

I will have to modify the bearing design as there is no way to adjust them if they are not 100% parallel to each other. This could mean that a bearing may not run along the rails correctly. At this point I have not tested this yet.

As this is an all metal machine I got a friend to weld me a box section frame to act as a soild base.

To this base I have been able to attach aluminium end plates which will support the guide rails and table.
I have used aluminium angle as the support for the mdf table bed

The guide rails are held in place with centering blocks which can be used to aline the rails.

For the z axis i saved some linear bearings from the skip at work. I have most of the z axis complete but no pictures so far, am hoping having this log will help me keep track of where i am and what i have to do..

As far as the electronics side of things go I plan to use the picstep drivers as I have 10 of the diver chips LMD18245

http://www.fromorbit.com/projects/picstep/

Although I have quite a lot to learn, ie. etch boards, program pic chips.
I am going to try toner transfer method for etching so I will let you all know how I get on considering its all new to me. Might try photoboard as I made a uv light box which I made, but again never used
Likewise with the pic programming will be a sharp learning curve, although I have i programmer I have never used. (more unfinished projects :rolleyes: )

I have not played around with the software side of things to much but will try turbocnc as I saved a pc from the skip which is a 200Mhz PII so I guess dos based is best for this machine, after all it will be out in my shed/workshop so I dont want a good machine out there.
As you can see I saved a few useful things from the skip at work, they are so wasteful, if its dirty bin it???? oh well one man rubbish, another mans gold :)

Well thats my posts for tonight, an hours work to show what I've done in a couple of months, hopefully as i post stuff as i do it there will be a bit more detail included.

One thing no one tells you at the start of all this is the mess your workshop gets into, I've had to pack away my current plane build project to make room, and now there is a helicopter to add to the clutter.

Like I said, 25 hours maybe more needed lol, its 1:50am here am off to bed

Poof I grant you a 25 hour day, problem is the hours are only 57.6 minutes long! :D

you are making great headway.

Watching with interest. Looking good so far !

You won't be dissapointed with the picstep drivers. Great boards, just shout up when your building them, there is a lot of help on here.

Good to see another 'skip-rat' :)

Cheers

Wey Hey! Nice to see another metal contraption taking place!
I'm afraid the best I can offer you is 24 hours 39 minutes; However this would entail relocating to Mars. Another bonus is you wouldn't have to worry about moisture in the workshop again. :D

I like your rod adjusters. Did you do them on a lathe or use some other cunning means?
Are you going to put some plates on the side of the gantry to make it more rigid?

Hi Guys thanks for the support nice to know am not just rambling off into cyber space lol.

The rod adjusters where made using hole saws, I had to cut both hole at once as I had only one saw holder bit and it wasn't the right type for the lager bit. The saws are 52mm for the larger and 25mm for the inner one.
Its a bit crude but when needs must and I wish I had a lathe :(

I must likely will add extra support to the gantry sides, I will wait to see what turns up in the skip lol.

Hi started to put things together just to see how things are going.
Mounted z carrier to the gantry, had to load bearings to take slack from bearings, I think there is a lot of flex in the 20mm pipe and I may look into getting soild rod. At the moment I have the gantry cross members tight to the rods to stop flex.

I fitted evrything together and it gives a good idea of how the final machine will turn out, I have put some measurements on to give an idea of size.

I will have a final cutting area of 42x69.5cm and a max height of workpiece 13cm

Can you not just keep the gantry cross members that way? That sounds like an elegant solution. Your gantry is going to end up very heavy when you're finished (even with hollow pipe). I think your table (X axis?) rods will definetly need some supports (and possibly made solid) as they bear the most weight. I've read some people people fill their pipes with concrete to increase strength (and improve dampening)

Very clever method for the rod supports! You could bang out lots of supports that way fairly quickly.

Hi 10bulls, yes I agree about the x axis rods so I will most likely get some solid rods as there might be no simple way to support them with the gantry lay out.
The weight is really adding onto this machine add I wonder if my motors will be up to the job. Its hard to source good 'cheap' steppers here in the UK.

I have to get started on lead screws and mounting the motors, I like the way xairflyer has used 12mm rod and turned the ends down to 8mm. I will have to get a mate to do this for me or i may just use 8mm to get started.

Anyone advice on floating nuts?

... as there might be no simple way to support them with the gantry lay out.
Can you not move the 'under gantry' cross piece above the x-bearings so the rods are free underneath for supports?
...Its hard to source good 'cheap' steppers here in the UK.
I got mine from http://www.arceurotrade.co.uk/ ~£30 for 180Ncm (255oz/in).
Anyone advice on floating nuts?
Tapped delrin (or nylon breadboard) works great for starters. Fancier AB nuts can be made later.

Hi robe_uk,

The machine's looking great!

Can I ask how you're cutting the plates of aluminium?

Cheers.

Hi sploo, the plate was cut on a guillotine at the local engineering works, makes quick and accurate work of it.

10Bulls, Unfortunately I am unable to move the cross support up as it will then interfer with the angle of the table support.
I have tried bolting some 20x20mm 3mm angle to the pipes to increase support, it helps but there is still some movement. wonder if solid rod will help more??
The lack of adjustment in the bearings is starting to bite because when the gantry is riding in the middle of the rail it can rock and have a bearing off a rail, I can not preload the rails any more without binding at the ends of travel.

Some redesign is required, this has always been a problem with working on the fly, things never quite run smooth lol. but i guess i never change, makes life fun :o

Solid rod will certainly help. I'm only using 18mm solid silver steel rods (unsupported). They are about a foot shorter than your machine, but I don't get a signifcant amount of flex from them, even cutting aluminium.
You *should* be able to get a degree of adjustment from those bearings by oversizing the bolt holes for the skate bearings and adjusting the bolts to a better position. Make sure your pipes are dead parallel first though, otherwise no amount of adjusting will get it to run right.

well not much going on at the moment, have to work sometime :devious: and when I finish shift I dont feel like doing to much out in the shed/workshop/den/hanger (doghouse if i've annoyed her in doors lol)

But trying to keep things going I had a go at toner tranfer onto copper board, I just used what I had laying about which is photo quality inkjet paper. Must get some glossy paper. Turned out ok'ish as some tracks came off, might have just been me not ironing it enough or rubbing paper to hard to come off. One thing about this paper is that it left glue on the board which may cause some parts of the board not to get etched. Needless to say out with the acetone and clean the lot off.
Also my laser printer with new toner and drum didn't put down dark a layer of toner as I hoped, it had some pinholes.
I have to get stuff from www.rswww.com so may try photoboard and use the UV box I made ages ago and never used :rolleyes:

oh one more thing, look at the lovely button I saved ;)

Well with the electroinc side of things on my mind I was considering what type of power supply to use.
I know linear supply is best for the controllers so was thinking of using 24v toroidal transformer rectified to about 34volts dc. But I was not sure about smoothing capacitor sizing extra and have been reading through many posts.

BUT strange the way things work out, I was at work today and was walking past the electronics bin and I spotted the item below.

It is some sort of controller that someone has dumped as faulty, but who cares about the controller side... just look at the power supply in it. (just one pic as camera battery died)

It is a 240v to 32vac transformer rectified to 40vdc, 20000mf cap with bleed resistor.
The current rating is 9A output which is great as my current motors are just 1A. so will get me started for free :wee:
Also the is a psu on board beside the cap which gives +/-5v +/-12v and 24v
Great Stuff.

Just one question, If I get 220Ncm motors that run 2.5A/phase, does that mean each motor draws 5A when running with the picstep controller?
3 motors = 15A
If so I will have to keep my eyes open then for more psu.

(cut out of psu bottom left was just my picture taking :rolleyes: )

Well not to much going on here as usual :violin:

I got some odds and ends in from Maplin's so I've had a go at etching a PicStep board.
As I've stated before I dont get a great print quality from my laser printer, which is disappointing as this was the main reason I bought it. The toner has pinholes and could do will being thicker. To try and over come the short comings of the printer I printed the circuit onto two transparency sheets, lined them up together and stapled them. This help but there was still some pinholes :mad:

As I have never tried this before I do not know what level of 'blackness' is needed?

Anyway with a do or die attitude I headed for the workshop to light up my homemade UV box for the first time in anger. (woohooo)

I got the Pre-Sensitised Copper-Clad Board (maplin small size is perfect for picstep) lined up with the transparencys and let her rip

...Anyway with a do or die attitude I headed for the workshop to light up my homemade UV box for the first time in anger. (woohooo)
Great stuff!
For my UV artwork I print onto sheets of tracing paper. Viking do pads of the stuff. This works great! Make sure to do a few test exposures first as underexposed boards will take ages to etch. Get your Ferric chloride nice and warm an bubbly.
Also, try www.megauk.com for pcb stuff. Probably cheaper and more variety than Maplins.
...and don't forget your shades!...you gotta look the part!

Watching the clock closely to time how long the board was getting exposed for..... hold on.... what the Freddy flintstone the hands on the clock are not moving!!!!

I had to guess the board was on for about 10mins, I wish i knew for sure so I could better gauge the next.

Right, now thats the board is exposed time to put into a sodium hydroxide solution (Caustic soda), really cool watching the circuit appear like magic. I think I left it in for to long as the writing on the board lost some lettering, although it may have been an exposure issue. I dont know??

As we see the board looks a lot better than toner transfer, so am not sure why people bother with it?

Nice one!
I agree regarding toner transfer. UV lightbox is cheaper and you can do double sideds fairly easily.
Don't worry about the lettering...Alan's ego is big enough as it is! ;)

Now time to etch, things are getting exciting.

Just had to nip in, get sprog to bed, back out to workshop.. oh am on a roll now....

I went over the worst pinholes with a permanent marker.

Mixed up some etch solution with warm water and placed into a plastic tray to etch the board. It took nearly half an hour to etch so as 10bulls says I may have not exposed long enough, also the fact the solution was not kept warm and had not air stiring it would not help.
Is this funny taste in my mouth normal, better ventilation required!!

I was really pleased with the way the board turned out, just about to start drill and I remembered that thing which 'i know i forgot something but what?' when placing my order... the correct size drill bits, the smallest I have is 1mm.

Oh well.. more for another day

just a quick update on the machine side of things, I have some 20mm solid chrome rods on order for my x axis and have ordered linear bearings to match, so a whole redesign coming for this side of things. If all goes well, the Y axis will get the same.
Hi 10bulls it great to have your input, I really like your machine, its driving me on :cheers:

Hi there. I'm not sure how I managed to miss this thread so far, but I'm along for the ride now. Great stuff, loving it.
Forgot to order your drill bits eh? Sounds like me. Axminster do a nice set of 50 tungsten carbide drills with some endmills thrown in if you're lucky. Around £16 for the 50 pc set. I got 2 sets, 'cause I'm greedy.

Keep the updates comming.

Reagrds Terry.....

Bugger. I forgot to post the link.

http://www.axminster.co.uk/product.asp?pf_id=20475&name=micro&sfile=1&jump=0

cheers bye.

As we see the board looks a lot better than toner transfer, so am not sure why people bother with it?

Guess it depends on your laser printer and the temperature and pressure of your iron. I've used the Press-n-Peel branded transfer sheets for ages and I get perfect results from my little Samsung ML1740 printer. I've always steered clear of the UV sensitive sheets because of their additional cost and their storage requirements, but each to their own, whatever works for you! :)

Your boards look good, well done!

Cheers,
Alan.

He's on a roll !

I do enjoy the writing style Robe. Adds a little 'humour' to keep things entertaining.

I'm with you on the UV method but probably as my PCB material is donated from scrap bits from work. I did dabble with the toner method and I nearly got it 100% but the junko laser I aquired was on it's last legs and now lives no longer.

From memory I expose for about 3 mins and also put two transparencies together to get a darker image. I use a 'Pritt-stick' to stick the two together and then staple the corners and sides to keep secure.

The fun is about to start, drilling those pcb holes :)

Keep those picture's coming.......

Cheers

Hi Alan & Santini

For my 2 cents worth here is my take on Toner Transfer.

http://www.cnczone.com/forums/showthread.php?t=11814

Post #3.

Alan especially for you as your in Aus. I tried and was successful with the press & peel but I am firmly convinced that the Pelican Inkjet Photo Paper from Woolies is much better and costs less for 100 sheets than I paid for 5 sheets from the States a few years ago. I still have some.

For others not from sunny AUS I think I saw someone one the forum talking about Kodak Paper and it was plastic but of course I cannot vouch for that, It may be that the Pelican Paper is rebranded Kodak????

Hi guys, don't get me wrong I never gave toner transfer much of a try so I guess it would be a matter of getting the right paper.
Plus the fact I had made a uv box, I just never had a way of making good transparencies, the laser printer at work never seemed to be working so I got a second hand one off ebay(Brother HL-820) which then needed a new drum and toner. .. sometime its better to go and buy new :rolleyes:
I am happy with the results I got, great work Alan

If fact my cnc journey started with me looking for a way of making pcb boards and I came across routing. So here I am making a cnc router/mill.

I am all ready thinking about making a smaller mill just for pcb's. Every time a printer gets thrown out at work I pull the rail and print head carrier out.
So I reacon I need 2 rails and four carriers per axis...just thinking out loud.

oh anyone know how to change the standard pcb art work into gcode for routing or can a package do it.. ie eagle? just downloaded and have to learn

MrBean thanks for link, bits ordered, have to wait before drilling starts, no harm as the suns been shinning and I've been trying to get that heli to hover in one place :eek: run...its coming at me aaarrrghh lol

Eagle will generate gcode, but you need a ULP script. You can download it for free. I tried it a while ago and it does do a good job. I can't remember exactly what it's called. Try googling for "gcode ulp"

Regards Terry.....

Well I got my drill bits and now I have a complete PicStep board :wee:
Well almost, I discovered I have no 20k resistors (nuts) but I think I can get some at work without having to go and order some.
Am not sure if the resonator has to fit one way round or the other (no fixed in yet).

Heres a pic of the picstep, Am impressed myself, cann't wait to try it out.

Oh b"£$"£$%"£$%

So excited about having the board amost complete I forgot I had to program the PIC.

No worries, just have to find where i left that programmer and learn how to use it :rolleyes:

Good stuff! Very neat job.
Resonator orientation doesn't matter.
One down - 2 to go.

Hi can I make two suggestions one brace your uprights with a 45 degree peice of extrusion to the horizontal bearing supports or a plate of aluminum in the corner, two back your rod with the extrusion run it down one of the grooves you can also attach with t bolts somehow. Just some thoughts I have been planning roughly the same Idea for some time now hope this will help or at least get the wheels turning.

Hi truman
I do intend to brace the conners for extra support, as far as the rods go I have ordered solid 20mm chrome bar (as used in hydraulic rams) which should give very little or no flex. I also have linear bearings in pillow blocks for the x-axis which will get rid of some skate bearing troubles I have. Just waiting for the supplier to get it in, always a case of 'it'll be in next wednesday, have to reorder it blah blah', turns out they are waiting to order a large batch of stuff from their supplier rather then the small amount I need. Very frustrating :mad:
All this has sort of knocked me off track, I haven't even programmed my picstep yet.

Motivation + 25hr day required now :rolleyes:

Added; just read over my thread and I see it was August when I order the bar, time for a new supplier I think. funny how time just rolls by. This is why my hall has been needing to be painted for over a year now lol. Pressure from her in doors nearly at breaking point but I think I get hold out for longer :D