Official Luthiers Forum!

Hi All,

Thought it was about time to start contributing something back after all the the great info I have read and learnt on here.

After a number of months of research and designing I finally kicked off building my new cnc, totally addicted to it now... not enough hours available in the day!

My main design criteria:

Accuracy, obviously needed for making guitars, templates, tools etc so I want to be able to ensure the accuracy is as good as it can be for a home built machine.

Cutting area, 1100 x 450 x 150, optimum area for the guitars etc that I make

Size, Over all 1400 x 700 x 600, Space available in my garage!

Rigidity, Enough said

Dust and noise, due to working in a confined space the cnc will need to have a good dust extraction system and also be enclosed to reduce operating noise (got to look after the neighbours!), and so i can work later at night!

So far I have managed to collect the following parts:

60 x 60 Extrusion for the gantry and bed
Hwin 15mm rails and bearing guides
1400mm RM2005 C7 ballscrew
660mm RM1605 C7 ballscrew
300mm RM1605 C7 ballscrew
3 x 570oz steppers
3 x 203V Geckos
Power-supply
Associated bolts and screws.

I had the parts for the bed laser cut, I was quite surprised how it worked out price wise and the accuracy is great.

Spent the last weekend preparing and building the bed, did the countersinking (after some fiddling around with the right depth) Tapped the rail holes, primed and sprayed (hammertone is great stuff! decide to go with charcoal).

Next fitted the ally extrusion to the side plate, loaded up the T slot nuts and fitted the front and back plate, then attached the other side.

Seems to have gone together relatively well and 'seems' to be fairly square, will need to do some checks on it though to make sure its ok!

looking foward to getting some more done as soon as I get the time (dang day job! )

Cheers
Glenn

Good Looking Machine! Best of luck with your build, and yes, please keep us updated on the progress....

One thing which is relatively new, is the new design of rolling ball nuts....not sure if you have considered that. if I was building mine again, I would opt for that....

You see, for the length of your bed, of 1400mm, driving the ball screw to high speeds, causes it to whip, and this, depending on the thickness of the screw, tends to limit the rapids. I max out at about 400IPM with mine, since anything higher, whips it, and causes a stall....not that I need anything higher in speed, but just for laughs and giggles...and bragging rights! LOL!

With a rolling ball nut, the screw remains stationary, and the servo is coupled directly to the nut, rotating it. With this, rapids would be close to 1000 IPM, if not more...which is quite good, for a machine which is not belt or rack and pinion driven...

http://www.thk.com/documents/us_pdf/pro ... 6rolro.pdf

Regardless, your machine looks really good, and let us know if we can offer any guidance or advise....

_________________
-CyborgCNC
http://www.cncguitar.com
https://www.facebook.com/CncGuitar

Cyborg, thanks for the comments, the rolling ball nut looks really interesting especially for the X axis... maybe in the future when I have some more $$!

Made a little more progress over the last couple of weeks.. lots of cutting, drilling, tapping, countersinking.. and tapping

I've started to put the main parts together on the gantry, seems to move ok on the rails with little binding, need to play around with things a little more though.

Gantry feels rock solid, no play or movement at all which is what I was hoping for!

I was working on the Z axis today, but in my haste I snapped a M4 tap off ... so I need to figure a way to get it out.

Hopefully by next weekend i will have everything assembled, then no doubt things will realllllly slow down.... the ELECTRICS!!

Cheers
Glenn

Been a while since i have had a chance to update the thread..

Managed to almost finish the machine, all steppers hooked up and running. Spindle wired and ready to go.

Just need to do the limit switches and table top.

Here's a couple progress shots and a vid of the first run with the steppers hooked up.




Cheers
Glenn

Nice looking machine, Glen. What's the second wire leading into the spindle?

_________________
http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Thanks Andy, the spindle has a independent cooling fan so that you can run the spindle at lower rps and it won't over heat, as opposed to having an integrated fan which spins as part of the spindle.
just waiting on some collets but hopefully get to test the spindle out soon
Cheers
Glenn

Nice job Lappy!

_________________
Brad
Avon, OH

That looks terrific! Of course I'm wondering what that program was supposed to be cutting, besides air.
Sometimes I wish that I'd built mine smaller like that.

_________________
"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

thanks for the comments guys!

Don - i think it was just some gcode i had for a sign or something or other, really should have tested out some guitar related gcode

I thought about making something bigger but was glad that i settled on this size, plus my workshop space is very limited!



Cheers
Glenn

Good deal man. I got my 2kW tekno spindle in the other day. Have my collets and such, just waiting for my VFD Funny thing is it looks huge on my machine and I accidentally made my mounting plate wrong - didn't realize that the bolt pattern on the back of the spindle was different from the sides - used the side spacing. It will still work though. Once I get it fully functional, I'll make a new one using the new machine (I made the current one on an old 3 in 1 machine).

I like the idea of a supplemental electric fan on there. I may have to make a plug in one for low speed work as well.

_________________
http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Hi Andy - VFD hasn't arrived yet??

I know what you mean about the size of the spindle, i was completely shocked when I took it out of the box, i freaked out for a second think it was going to be too big for the cnc
I will need to rebuild a couple of parts on the Z axis as well, just not quite getting the clearance I need, some how miscalculated it, lucky i have the cnc to make the new parts though!

Cheers
Glenn

I suggest you add the second ballscrew to that gantry. You will eventualy. Might as well get it out of the way now.

That's freaking awesome dude. I wish I knew how to build one of those myself. Out of curiosity, how much cash did you save by building your own?

Thanks - I actually wouldn't say i saved anything, it was almost on parr with buying especially since i had to outsource some of the parts, buys tools etc..

The only reason i went down the build route was i had bought a prebuilt cnc but i had a few issues with accuracy that I couldn't seem to fix. I sold it then used the money +sum to build this.

If i was in the US and was able to physcially see and test some of the CNC's you have available i would have purchased one instead of building.

Great experience building though, you really get a good knowledge of whats goes into the CNC, how it works etc etc..