Official Luthiers Forum!
http://mowrystrings.luthiersforum.com/forum/

Inlaying purchased shell with CNC
http://mowrystrings.luthiersforum.com/forum/viewtopic.php?f=10106&t=31563
Page 1 of 1

Author:  Andy Birko [ Tue Mar 22, 2011 8:41 am ]
Post subject:  Inlaying purchased shell with CNC

So as I wait patiently for my machine to arrive, I have a lot of time to ponder stuff and all this logo talk has me wondering a few things.

What's the best way to cut pockets with CNC for pre purchased inlays? I have little interest in learning how to cut my own shell as it sounds extremely expensive but, being able to buy an inlay from one of the many diplomats out there, scan it in, generate the G-code and cut the pocket would be pretty cool, even if you had to clean up the corners a bit with a chisel.

Does anyone do that here?

I've also read on this forum that many of you sneak up on the final size of your inlay a thou at a time. Are you doing this in your cam software or are you using a feature in your controller to do that? I know that Mach3 (what I'll be using) does have a scaling feature but it's not clear to me exactly how do use that to sneak up a thou at a time.

Does Mach have a way of compensating for a smaller tool? It seems that you could drop the tool diameter by .0005" with each pass to get a thou bigger pocket if that's possible.

Thoughts?

Thoughts?

Author:  Mike Kroening [ Tue Mar 22, 2011 10:07 am ]
Post subject:  Re: Inlaying purchased shell with CNC

Andy,
There are different ways to sneak up on it. It can be done using the cam software and setting an offset. Or setting a tool diameter in the cam software as well. Also Mach 3 has in the "offset section" where you can set this for tool compensation of diameter. The scaling in M3 is not the way to go for this though.

Mike

Author:  Bob Garrish [ Tue Mar 22, 2011 4:31 pm ]
Post subject:  Re: Inlaying purchased shell with CNC

Andy Birko wrote:
So as I wait patiently for my machine to arrive, I have a lot of time to ponder stuff and all this logo talk has me wondering a few things.

What's the best way to cut pockets with CNC for pre purchased inlays?


With the tool that cut them. Cutting pockets nearly always takes significantly less time than cutting the inlays, so it's a small upcharge.

If that's not an option, then you could give them a CAD drawing you generated so you'll have proper dimensions for the pocket. Reverse-engineering something that small is no mean feat, and it requires a lot of trial and error (ie: wasted material) to dial it in. Or convince them to send you the CAD of the logos.

Author:  Parser [ Tue Mar 22, 2011 5:56 pm ]
Post subject:  Re: Inlaying purchased shell with CNC

I agree with Bob & would recommend cutting the inlay as well as the cavity. You'll learn a lot if you can do this stuff on your own...and if you have a CNC it makes sense to do so..!

Here are a couple screenshots I posted awhile ago showing a bit of my process:
Image

Image

Image

Give it a shot...!

Trev

Author:  Kevin Waldron [ Wed Mar 23, 2011 7:28 am ]
Post subject:  Re: Inlaying purchased shell with CNC

Parser has helped me a lot .......... but I would some what disagree on this issue.......... Depaul offers many excellent inlay ........... there is a learning curve to being able to take the inlay and use it with the cnc or laser........... but it is a do-able project and not as hard as you might think.

Take your inlay ........... scan it with a good flat bed scanner.......... use a conversion software (Corel, Flexisign, Vector Magic, or other) or even pay some one else to convert it if you will be using a lot of this inlay and you don't want to do it. Cost for conversion on 2-4" is usually $15-$50 . Basically with a purchased inlay you only need the outline not the parts and pieces that make up the graphic. Once you have a dxf file or other vector file simply a matter of processing the pocket either on a cnc or a laser in our case. ( most of the time ) Advantage to laser are square corners, .002 accuracy, and no hold down necessary .......... disadvantage of the laser is actually burning the material out of the way......... not all material are the same density and it somewhat becomes a matter of experience as to how long and how deep. ( it is also possible to cut inlay with a laser but it does take a more powerful laser than most of the mom and pop shops..... have........ also some trade secrets ha!.......... we also have cnc but I never did like using micro-bits if I didn't have to.)

We have not been in luthier near as long as many of the guys on this forum but we for sure have done our share of inlay in a short period of time.......... don't let them discourage you.......... find something commercially available that you like.........then use it.......... after all our most valuable resource is our time. ( if we do the math most of the time the bought inlay will always be cheaper.......... even if you have someone else customize the inlay just for you)

kevin

Author:  Parser [ Wed Mar 23, 2011 5:40 pm ]
Post subject:  Re: Inlaying purchased shell with CNC

I think Kevin brings up some very valid points - well said Kevin..!

Besides that, I'm pretty sure Kevin is a better business man that I am, so you might weigh our respective advice with that in mind as well :D

Have fun, whichever way you decide to go..

Trev

Page 1 of 1 All times are UTC - 5 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/