Official Luthiers Forum!

Hi Guys,

A couple of weeks ago i decided to build a CNC Machine but saw that most plans and building costs where cost prohibitive, I then went to www.cnczone.com and found DIY Plans for a wood CNC Router made from MDF. Many people have made this unit from the FREE plans available from the site. Don't let the MDF fool you, this is a very nice machine when properly sealed with shellac and paint. most are getting an accuracy of .005 in and 30-110ipm cuting speed depending on the size stepper motors used. Construction cost including electronics is $300-$500 (486 or greater coputer not included). I've decided to build this model myself. To get the plans you need to goto the site and register for free and then you can go to the download page and look for the file with the name JGRO you can also do a searh to read all the post about it. Enclosed is a picture. Tell me what you think of this Idea for rough carving archtops ect.

And what software does it interface with? I think I remember somewhere that the real "hidden cost" in DIY CNC is in the software interface (and moving to servos vs. steppers.)

I have always been tempted by this... if for no other reason to play with the gagetry. It looks like a lot of fun.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Me too...please keep us informed. Also, looks like you could use a vacuum system to hold down the top as there is plenty of clearence.

Hey Brock...there's an idea for a seminar...build your own CNC! That would be great. One or two day building it ( or going over how to buid it at home) and then maybe a day or two learning to run the thing.

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Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

That is a great idea.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Very cool Ed!!

Couple of questions?

"X" ,"Y" and "Z" lead or drive screws what type and size of thread?

What are the follower bushing that correspond to the lead screws made from

Ed--I use a similar sized CNC for rough carving my plates. It is a Techno-Isel with servo motors retrofitted to replace the steppers.
One issue to consider is the duty capacity of the router motor used. I run the Bosch 1617EVS which works okay but have to replace the bearings occasionally. Could probably slow down the cutting feed rate and get more router life but get tired of hearing the noise.
One way around that is to go upstairs and surf the OLF while it's running.
I use vacuum to hold the plate while roughing the outside and then have a clamping setup for roughing the inside.
Nelson

I'd love to build a cnc. Not sure where I'd put it, but I guess I could always tear out a wall or two and throw out some rosewood planks to make room.
We also have a resident expert here, John Watkins, who has built a very nice cnc for himself, and has done some great looking work with it. Maybe he will chime in...

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"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."

John's in the spray booth. Finishing those electrics. Doubt he has time to sit on his duff like the rest of us lazy people.

Don--You may have to chuck a rock over there and get John's attention.
Nelson P.S. Here's a shot of my CNC roughing out a top plate.

Brock, As far as the software there seem to be many low cost solutions < $150. As far as steppers vs servos, servos cost more and are faster but my friend who works with many cnc machines say's that servos are not as reliable as steppers. My friends say's they have to change out the servos every so often on most of the machines they have that use them. I'm a newbie to this so I really can't say that this is the case for all servos.

Nelson, That is a great looking machine. Did you build it or purchase it? how do you like cnc? do you have any trouble with your servos?

As far as the scew it is an acme unit about $24 and uses Delrin for the follower bushings I think. Sorry I'm not use to the terminology yet.

Ed--I bought the Techno-Isel on Ebay several years ago. It had steppers on it with the Techno-Isel control. I retrofitted it with servo motors with encoders and bought a control from a fellow in Canada.
I also have a little Maxnc10 benchtop mill that I've used for several years for making small parts such as the tailpiece, pickguard, bridges, headstock machining, inlays and inlay cavities, fretboards etc. It originally had underpowered steppers so I retrofitted it with servos and drives also.
I like CNC because, as I alluded to above, I can be messing around on the OLF while the CNC is carving a top for me, as it is at the moment. Seriously, it is very productive to be able to do something else while the machine is running.
Nelson    P.S. I use the Mach2 controller software.

nelson, I just downloaded the mach3 software it looks pretty good have you seen it?

Well guys I'm going to go ahead and start building one next week. I'll keep you posted and let you know what problems I run into and what observations I have. Nelson, what is the cutting area of your machine? I'm going to build one about 2'x4', I've always wanted to try and build a cello.

Ed--It's about 20"x22". Don't short yourself on Z axis travel.
I have not seen Mach3. I'm curious whether it will allow feed rate override "on the fly". That would be an improvement over Mach2.
There is a company in Kansas City (kcstrings.com)that uses CNC to carve cello and bass plates.
Nelson

What Z axis travel/clearance would you recommend?

Ed,

I too am interested in your progress and would be really interested to know where you end up getting all of the bits and pieces and what the final cost is as well as how well it works. I have been to the cnczone.com site before and have thought about putting one of these units together. After I build a couple of guitars though!

Thanks for including us in your project.

Shane

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Canada

Ed--I have about 6" travel on Z with the lowest point putting the router collet at about 2" above the table. The 6" is probably enough but there are times I need to get the tool down a little closer to the table depending on how the workpiece is fixtured. I can reposition the Z slide base lower or higher but would rather avoid having to do that.   I have some setups where I have to mount a tiny endmill in an extension sleeve to get the cutting edge to depth.
Might mention also that dust control is a big issue with a CNC router. I built a plexi housing with "walrus whiskers" hanging down to "seal" the chips as much as possible so the airstream can pick them up.
Nelson

Yah, dust control... it's a whole other world with a cnc. You have to stay on top of the dust with those things.
The great thing about the noise issue, is that there are some new routers out there that are really quiet if you use a router for the unit. I think I'd rather have a multi-tool spindle, but at t his point I'd settle for a home-made cnc with a dremel.

There are also the nice quiet shopvacs like the Fein I have. I hardly notice it's on, it's that quiet. Just hook one of those up and you're golden, except you would need to empty it frequently.

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"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."

i have been thinking of building a duplicarver type machine for roughing out necks, and violin and mandolin plates, but the relatively small cost of upgrading to one of these seems well worth the consideration, especially since the accuracy is much greater and it does not require my attendance whilst doing its job.

please keep us informed of progress, pitfalls, etc.

and any comments on how difficult it is for technodopes like me to learn to operate the beast would be most welcome as well.

Nelson, Mach2 does do on the fly feedrate changes. The control is right here:



Maybe if you turned some lights on....     

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John Watkins
CNC Guitar Parts

[QUOTE=crazymanmichael] i have been thinking of building a duplicarver type machine for roughing out necks, and violin and mandolin plates, but the relatively small cost of upgrading to one of these seems well worth the consideration, especially since the accuracy is much greater and it does not require my attendance whilst doing its job.

please keep us informed of progress, pitfalls, etc.

and any comments on how difficult it is for technodopes like me to learn to operate the beast would be most welcome as well.

[/QUOTE]

I am tempted by this too... however from what I have read, the real cost comes in with the investment of software, time, programming etc.

With the duplicarver you just set it up and go, but the CNC is much more of a learning curve if you are not already an engineer familiar with this equipment.

Maybe one of you guys who are using this already (Nelson?, John?) you could talk about that. Is there a source where you can learn CNC for dummies?

Brock Poling38650.5156018519

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Yes please tell more. I also have been looking at making a duplicarver for necks and other parts but a CNC...

John--I can't find the lightswitch. Besides, someone told me that "lights out manufacturing" is cool.
I do override the feed rate but it doesn't take effect until there is a change in Z.
Brock--My problem is that CNC as well as CAD/CAM, in my case, has been a learning experience over the last 35+ years and the learning curve is steeper now than ever. My recommendation would be to start reading the wealth of information on the web which should direct a person to some good basic books/videos on CNC. I'm happy to answer any questions I can but don't have a good feel about the best place for a newbie to start.
Nelson

If you've got about $5k to spend this is a good turnkey unit:
http://www.shopbottools.com/
-C

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Freeborn Guitars
and home of BeauGuard©

Oh great, we started at $500 now we are up to $5000

[QUOTE=Brock Poling] [QUOTE=crazymanmichael] i have been thinking of building a duplicarver type machine for roughing out necks, and violin and mandolin plates, but the relatively small cost of upgrading to one of these seems well worth the consideration, especially since the accuracy is much greater and it does not require my attendance whilst doing its job.

please keep us informed of progress, pitfalls, etc.

and any comments on how difficult it is for technodopes like me to learn to operate the beast would be most welcome as well.

[/QUOTE]

I am tempted by this too... however from what I have read, the real cost comes in with the investment of software, time, programming etc.

With the duplicarver you just set it up and go, but the CNC is much more of a learning curve if you are not already an engineer familiar with this equipment.

Maybe one of you guys who are using this already (Nelson?, John?) you could talk about that. Is there a source where you can learn CNC for dummies?

[/QUOTE]