Paul's CNC

[paulplaysguitar]

Hi there.
I'm biting the bullet, I've got some money, I've done a bit of research and I'm finally getting on with my first CNC.
My intentions at this time, are to build a Joe's CNC Model 2006 http://www.cnczone.com/forums/showthread.php?t=17279. There are several reasons for this:
1. It's made of wood (well, MDF anyway). That's good. I can do wood.
2. It's working area is roughly 4 x 2 ft. That's all I need for now.
3. The plans and drawings are freely available, although the provided DWG file is in imperial measurements and is somewhat awkward and needs some readjustment, I think. (If anyone can help out here, it will be much appreciated)

I intend to get a Xylotex 3 Axis Drive Box kit. It comes prewired with motors, a box and fan etc. There is hardly any price difference between the 269 oz.in. model and the 425 oz.in. model, so I thought maybe 425 model might be better, though I don't have any real reason for thinking so. The dollar is not so good at the moment, so I'll be spending roughly $200 more than just a few weeks ago :C.

This is my first CNC. I know nothing. So if anyone wants to reply with a :oDear God Paul! What are you doing???:o note, go right ahead. I'm open to suggestions...

[Greolt]

Welcome aboard Paul. :)

As far as an all MDF router goes, I have not seen a better design than the Joe2006.

There have been a lot of these built and I would be surprised if there is not a set of drawings for metric sized MDF floating about somewhere. Perhaps ask in the Joe's forum at CNCzone.

It is critical that all the MDF bits that cradle the pipe rails are identical. They are most often cut straight from the drawings with a CNC router.

However they can be made with a template and hand held router. Make sure you get the pipe before cutting the MDF. The rails must be a snug fit.

I suggest you skip the allthread and go straight for ACME screws with "dumpster" anti backlash nuts. Most who build this machine quickly upgrade to ACME screws.

Many here are Xylotex fans. I think there are better options but if you need "plug and play" then maybe that is the way to go. And yes for this application I would go for the bigger motors.

There is a lot of help to be had, here for local info and CNCzone for general help. You just sometimes have to "filter" the advise a bit. :) (not here, on the zone)

Greg

[chrisb691]

Dear God Paul! What are you doing??? :o

Welcome to the crazy world of CNC, it's going to suck the rest of your life away. :D

I'm well on the way through my first build, and probably had all the same questions as you. They're a marvelous mob in here, and are some of the most helpful people you could hope to meet.

I looked at the Joe2006, and decided that I probably couldn't build it accurately enough by hand. My you, that purely relates to me, as other people have done it. I ended up going for a desgn from buildyourcnc.com, which is a much simpler design. It's not as good, but was makeable by yours truly. My intent is to use it to build the joe model. :)

I think you are right with the selection of the 425oz motors, as you'll need them to drive the rapid type of leadscrews which you will ultimately fit (IMO). I also got the plug & play box from Xylotex. However, after a lot of thought, I went for a 4 axis kit. All my reading seems to suggest, that there are a lot of cnc bulders that say "I wish I had a 4th axis". At the very least, I now have a spare motor, and spare, drive if anything should go wrong. At this point, there is not a huge difference in price between the 3 and 4 axis boxes, and it's a lot easier getting the 4th axis up front.

A word of warning. Do not under-estimate the effects of building an imperial design, using metric materials. It has a real chance of biting you in the bum. In my case, I managed to adjust for everything okay, but the accumulated differences got me when I went to fit the leadscrews. I got it done, but had to do some rapid footwork in the last 2 days.

Also, you need to remember the forum mantra "This thread is worthless without pictures". So make sure you make a pictorial record of the build.

[paulplaysguitar]

Chris and Greg, thanks for the advice.
I'm not a metalworker so here's some dumb questions.
What sort of pipe should I use?
And where do I get the ACME screws with "dumpster" anti backlash nuts from? (ebay didn't have any)

[Greolt]

Don't know what sort of pipe the drawings say but most likely won't be able to find the exact same here.

Dumpster link, http://www.dumpstercnc.com/

Acme screws, Read up on the zone but I think they are using 1/2" 8, 2 start.

You won't get that in Aus I think. Get used to buying from OS. :)

Greg

[Ch4iS]

You won't get that in Aus I think. Get used to buying from OS. :)

Greg

And you will love the exchange ratio right now.


BTW I think the Joe2006 is a little out of anyones league unless you are a woodworking god. From the dawings it is made to be cut with a cnc router (ie. no inner corners)

Good luck thou, my first attempt was a complete failure, my 2nd was also but my 3rd works somewhat (Build thread is around here.)

[paulplaysguitar]

In the available drawings for Joe's 2006 CNC, the pipes are labeled as 1 inch and 3/4 inch "gas pipe". According to my father in law, a retired plumber, Australian copper gas pipe comes in imperial external diameters! :2tsup: It also seems smooth, straight and hard? enough for the job (again, I'm not a metalworker, so give me the ":oDear God Paul:o" note if you like). This is good. It means I don't have to try to modify Joe's drawings to accommodate metric pipe.
I had another thought. Joe's drawings seemed a little awkward for metric measuring at first, mainly because of MDF thicknesses. American 1/2 inch board for example, is 12.7mm, ours is 12mm exactly. Naturally, this would cause some sloppy joints. My original intention was to modify the drawings to accommodate metric thicknesses, but if I use veneered MDF and thickness sand it a bit, I can have virtually imperial sized thicknesses and not have to worry about drawing modification at all (CAD is a little beyond my capabilities anyway). eg. veneered 18mm MDF is 19mm which is near enough to 3/4 inch (19.05mm).
How does that sound?

[appiwood]

Hello Guitarman

Your ideas on your new machine sound like a plan, have you posted any messages on CNCZONE about metric plans for that machine, someone may have converted the plans already.

One thing that did bother me was that you can't work around in CAD yet, I share the view that building the machine is the easy part, unless you have someone who is going to do your drawing your machine will sit there.

2D CAD isn't hard once you have drawn your first line, it's like walking it will fall into place but the first step is the hardest.

ED

[paulplaysguitar]

I did post a note on CNC Zone, I got a reply, but no one offered any modified drawings.
The main problem I have with CAD is I don't really have a CAD program. At the moment I'm using Adobe Illustrator to adjust things around a bit, it's more for graphic design than drawing, but it works well.
If you want to suggest a good freeware program...
You're right though, I really only need to adjust the cross-halving joints a bit to accommodate metric sizes. Shouldn't be too hard.

[appiwood]

Hello Guitarman

I don't have any suggestions as to CAD - I'm using a >10 year old copy of Autocad, I don't have the plans you mention either, but if you can send them to me along with which parts you want changed I'll do it for you, have you got access to a machine to cut them ??

Ed

[twistedfuse]

There is a small company called progeCAD or similar which uses an IF very similar to auto cad. I think from memory it is free for home use??? Not sure. Either way if you just want 2d this wouldn't be a bad package for what you need i think. I use'd it for a few pdf to dxf conversions, but other than that not sure.

Daniel

[appiwood]

Hello Guitarman

Did you not read my offer to convert the drawing parts for you???

Ed

[paulplaysguitar]

Thank you Mr Ed. I did note your offer, but I'm having a go at it myself. It's taking rather a long time, it's not difficult, but I'm thinking if you knew just how tedious it all was, you would regret offering your help.

I've bought the pipes, not the copper ones I mentioned before, they were unsuitable and the wrong size after all. The drawings of Joe's 2006 model CNC show them as 1" and 3/4", but those are in fact, the internal diameters. I got some seamless steel pipe, but the suppliers will only sell 6m lengths, and they mucked up the smaller pipe, wrong size. I'm taking it back tomorrow. AND some of the blasted pipe was rusty! That can't be good for smooth tracking. Luckily, the rusty pipe is the one I'm taking back.

I've ordered the dumpster thingys and the bearings, but I'm having difficulty finding the acme 1/2-8 threaded rod I need. I tried McMaster-Carr, but "...due to the ever-increasing complexity of U.S. Export regulations, McMaster-Carr has decided to only accept orders from a few, long-established customers of ours overseas...", which is a round-about way of saying "we can't send 6ft lengths through the mail". They don't say that on their website though, do they?
Having already ordered (and paid for) the dumpster thingys, I'm now committed to using the acme screws.
Oh well...

[appiwood]

Hello Guitarman

If you are taking the pipe back, ask for a price on bright bar and hydraulic bar, the second one it the stuff that hydraulic cylinders are made from, for short lengths your best bet may be an engineering business for all three type of steel, I googled engineers in Nowra and got this " ARCTEC ENGINEERING
Victa Way
Bomaderry, NSW
PH : (02) 4421 3822
FAX: (02) 4421 5663 "

If they can't / won't sell to you they might have a suggestion, normally you will pay a premium for short lengths but it may still be cheaper, failing that, Horan Steel deliver to her in the Central West of NSW, they are cheaper than either of the two local suppliers and deliver mon' - Thursday,
here are the details,


165 Newton Road
Wetherill Park
Telephone 02 9203 1111
Facsimile 02 9725 3871

Good luck with your drawing, I wouln't have had a problem with doing it as I see it as a way of keeping the CAD skills sharp.

Ed - I'm not really a Mr type either.

[rodm]

For your Acme thread try Woody as he might still be helping us Aussies out
http://www.cnczone.com/forums/showthread.php?t=54291

If that falls through then Hoss is a great bloke and might help you out if you get him to machine the ends as well. His prices are very competitive on end machining and it is something you will have to do anyway. I have seen where he supplies acme, machines and ships out to other countries so ask.
http://www.hossmachine.info/

[paulplaysguitar]

Um.... Can someone remind me why I'm having to machine the ends??? :?

Did I mention I'm a woodworker?

[paulplaysguitar]

And where do I get 3/4 inch "water hardening drill rod" from???
Or is there a substitute?

Thanks for all your help by the way, I'm learning heaps.

[rodm]

The screw needs to rotate so it has to be supported each end by a bearing. You also need to couple one end to a motor or a pulley. Sounds complicated but it isn't. Machining is an issue if you or a friend do not have a metal lathe. If you can get it done by a supplier then problem solved. Check Hoss's site and there are other ways of doing it from cheap skate bearings through to angular contact bearings and tapered roller bearings.

[rodm]

Paul I missed the bit about only being a woodworker. We are all from woodworkering backgrounds and learning as we go so you are in good company.

I am going to try to steer you away from the fabricated pipe and home made bearing slides. Personally I think you will spend almost as much money (if not more) sourcing the pipe and parts and heaps more time fabricating your own bearing than buying commercial rails.
It sounds like I work for the fellow but I don't and he has delivered affordable commercial rails to a few of us on the forum in the last couple of months. An example is a complete set of rails for a machine (6 rails and 12 bearings) for $250 Aus plus shipping. Modify your design to incorporate these and ask for diferent sizes as he is very helpful.
http://stores.ebay.com.au/linearmotionbearings_W0QQssPageNameZstrkQ3amefsQ3amesstQQtZkm

If you already have the pipe and other parts then I would not suggest the above alternative. I have built very strong home built rails with 50 by 25 solid bright steel bar stock and knowing what I know now and the recent availablity and price of commercial rails I would not do it again.

If you are stuck on your pipe rail design then that is good too.

[appiwood]

Hello Guitarman

I would agree with Rod, I'm guessing that most of use who have been doing this for awhile would agree, at first homemade looks to be the way of keeping the boss happy ( if that can be done ) but it allways is a compromise and I'm not convinced that it is really cheaper, if you want to build a machine to get on with your woodwork then itdefinetly isn't, if you enjoy " tinkering " then maybe.

The other thing is, for me I can take great satisfaction of designing a machine,building the rails, linear bearings.............................. but when finished it looks like a homemade machine, the second or third machine will benefit from the " early " days and will look better, I went the commercial route because like Rod the price of commercial is affordable when sourced overseas.

As an aside, some Australian companies just don't have a clue, I am rebuilding my machine and have bought all the parts in readiness, just about the last part was the Y axis belt, I ordered it from Econobelt but ordered a 1100mm long belt instead of a 2100mm belt, this came to light on Sat' the belt from the states will cost about Au$80.00 to land here, I rang a Melb based supplier today and yes they can make one ordered in from O/S for $175.00 or can do so here, the belt made here will lose about 1/2 of it's strength due to the wires not bieng contuinous, so I increased it from 16mm to 25mm, bit better in price $168.00, but the crunch is they will only make a min' of 2 so the price becomes $336.00 + 15.00 to get them here $351.00 or $80.00, This my son is why we bring stuff in!!

Ed