One out of 18mm MDF in the Netherlands

[Witsenburg]

Well, at least, that's the plan. A little backround:
Af few year ago I checked the DIY CNC forums and everything was new, difficult and expensive. Now I'm pretty lazy myself (hence, I want to fit my router to a CNC machine), so I decided to wait a little. Now, I see many good, cheap ideas have evolved. It was worth the wait!

So, after reading through some threats here, I sat down and fired up the old AutoCAD program. I've attached what I came up with so far.

The idea is to make identical X, Y and Z rails, only use two for X, one for Y and one for Z. The rail consists of 3 layers of 18mm MDF. The outer ones are 150 mm tall and have the long sides 6x6 mm chamfered. The middle one is 134 mm tall, and glued central between the outer 2. This leaves top and bottom channels that perfectly take a 33,7 mm thick-wall gas tube.

Some aluminium angle, bolts and ball-bearings make up the skids, the upper skid can be clamped down on the rail using bolts.

I'm thinking about using double steppermotors instead of one large one for the X drive.

Please feel free to (constructively) comment the design.
Thanks,

Hugo

[Witsenburg]

OK, after a lot of research and buying some second hand motors, I finally started building. Not too difficult, just lots of MDF and some stainless bits. I work at a food-machines producing factory, stainless is easy to get hold of. Only downside so far is that it is all pretty heavy, but even without proper bearings on the threaded bar and no lubrication, it stil turns fairly light. I hope uploading the pics works...







The rails for the Y -axis is ready, too, and the rail for the X-axis, which is actually the table, is assembled dry, I will glue it tomorrow.

Cheers,

Hugo

[Witsenburg]

This was a good weekend, I did the final assembly of the machine, with the exception of the spindles and motors. Here are the pics.

Overview of the bed, 620 x 1220 mm. That's a standard MDF board at the Gamma DIY store here in Holland...


Y-axis cart with the space between the housing and the wood that holds the angle iron: there are squashed rubber buffers mounted in there to keep the wheels under tention in the rails at all times. Every axis has this on my machine.


Z-axis, same thing only more narrow.


Both X-axis carts, one fixed and the other one with the rubber tention buffers.




The whole thing, on rather flimsy stands. The idea is to make a stand on wheels with the computer, drivers, powersource, etc, and a vacuum cleaner. Machine on top, ready for use. Just not sure where to place the monitor, keyboard and mouse, yet.


Well, that it for now. Just ordered the drivers and power source last Wednesday, but despite the quick answers to my questions before order, my e-mails post-order seem to have less impact...

Cheers,

Hugo

[Menno]

Nice, looks like a solid machine with the fully supported linear bearing.
I see you're using metric threathed bar as spindle, do you notice any backlash?

[Witsenburg]

Yep, the spindle is M16, and is has some backlash. But the weight of the unit pretty much cancels it out, since this is the Z-axis, so it is placed vertical. The X and Y axis get 16x4 mm trapezium thread (English??) which probably also has some backlash, but it is a machine to rout crude shapes which will get hand finished anyway. I make musical instruments, I don't want to loose the human aspect in making them too much.

Cheers,

Hugo

[picbits]

Looking good - I'm just building my own CNC/PCB drilling machine out of 18mm MDF (it has the same stickers on as yours !!!)

I'll be a bit more careful with it tomorrow as I managed to split a piece earlier today but its coming together.

[Witsenburg]

It's up and running, see movie posted in this thread:

http://www.cnczone.com/forums/showth...489#post313489

Because of the issue mentioned there, please let me know your accelleration / decelleration settings if you have a similar machine. Mine is an MDF Lionclaw-ish machine.

Cheers,

Hugo

[Kevin Lamers]

Hi,

Nice machine!

What are totall costs to make one?

Í'm planning to make something like this but a little bit smaller (X = 500 mm Y = 300 mm and Z = 100 mm)

Yours,

Kevin (also from holland)

[Kevin Lamers]

Hi,

How strong motors do i need you think?

Kevin

[Witsenburg]

Hi,

Well, the machine is really up and running, now. Since the first movie, I’ve changed acceleration settings and added home and limit switches, so the CNC bit is now fully operational. See here for the second movie. What’s missing is the router; I’m now designing the cradle for that.

As requested, some costs:
Pentium3 with windows XP home Free (thanks, Richard)
Mach3 controller software US$ 150.00
3 MSD542 drivers £ 85.50 excl. VAT
2 PS407 power sources £ 81.66 excl. VAT
(all from Motion Control Products in the UK)
C10 breakout board by CNC4PC.com US$ 38.00
Lots of MDF € 150,00
Micro switches and lots of shielded wire € 60,00
Two big HY 200 3438 motors, second hand € 90,00
(Marktplaats.nl, the Dutch e-bay)
One small 57BYGH728 £ 16.50 excl. VAT
(Again Motion Control Products)
A 10V zener and a 7805 € 5,00 (wrong shop)
Stainless steel and bearings € 100,00
Threaded barstock M16x1,5 and 16x4 € 100,00
Nut, bolts, screws, etc. € 50,00
Miscellaneous € 100,00

I think all in all that’s about one thousand one hundred euros. Which is a lot of money, but not much for the machine I now have. BTW, this does not included the spindle motor yet (my trusty Porter Cable) and all the money spent on items that didn’t make the final cut (other second hand motors that didn’t work, DIY drivers that proved unreliable, etc). I think it all I spent about € 1.750,00.

And about motor size, that's always an educated guess. Just look at similar sized machines and see what is used. Mine now has a work area of 890x550x200 mm. I think it could be handled by smaller motors, if acceleration is less of an issue. Getting this whole gantry going quickly requires some force...

Cheers,

Hugo