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Hey Everyone!
Finally got my logo drawn up. Roughed in pencil on vellum. My question is what comes next? My goal is to have this logo cnc inlaid onto headstock overlays. I have someone close that is willing to do this for me but I need to get the logo into the proper format (I think) for him to use it.

Thanks,
Chris

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There is no difference between the man that thinks he can....and the man that thinks he cannot.

Hey Chris,

Can you show it? What kind of file does your cnc guy need? I'll be willing to help if I can.

Mike

Hey Mike....thanks a bunch for the help. I'll check with my friend and find out what file format he needs.

Here is the Logo. It's the best I can do with my limited photo manipulating experience. I can resize them and that's about it. Check your pm's.

Chris

_________________
There is no difference between the man that thinks he can....and the man that thinks he cannot.

My guess is your CNC guy will want the art in DXF (data exchange format), DWG format (AutoCAD drawing) or some other cad drawing format so that he does not have to draw in up in his cad system. Otherwise expect a drawing setup fee. You see the CNC reads vector data to make the cuts if you provide the CNC operator a JPG or other digital graphics he has to create the path geometry. If provided in DXF, DWG or other cad format the file is the numerical geometry. JPG and other graphic images are raster images (series of dots, not numeric information)

Hi Chris,
Attached, if it works, is a quick tracing of your logo I did in Rhino. I drew it as close to the image as I could, but I do have some suggesions...assuming you are interested!

Get with your cnc guy and find out what the smallest bit he wil use for cutting this inlay pocket. Make all your inside radii the same as in bit. This allows you to draw this the way it is going to look, rather than just close.

Second, I don't know if your artwork was to symetrical or if you intended it to be asymetrical. I will need to know that as well and then I would need to know the smallest width of any part of the art work to make sure the smallest bit the cnc guy uses will indeed be able to get in to make the cut.

Mike

Hey Mike....here is some of the information you asked for.

Length = 1.940

The smallest bit my cnc guy has is .0092

The narrowest line on my drawing is .024

Call me back when you can - I have some questions about the outline Rhino made. In short...Rhino outlined details of the drawing that I had no idea were even there. Craziest thing I ever saw. I'm excited. Thanks by the way for the help and work you are putting into this.

Also - as the asymmetrical question...yes...we drew it off center and out of whack on purpose. I do however think the C needs to be centered, which it's not based on the tracing. Hopefully that address what you were talking about.

Chris

Michael - Thanks for that information. It helps.

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There is no difference between the man that thinks he can....and the man that thinks he cannot.

Find out how much flute length he's got on that nine thou cutter; a lot of them at that size have very short flutes and won't make it through shell over a certain thickness. A normal micro end mill only cuts to 3 X diameter which would mean you'd have to use 0.03" or possibly 0.025" shell blanks. You can special order them with up to 6 x diameter flute length which will allow you to cut a normal-thickness (0.06") blank. It's not so important on headstocks, since you inlay the pearl into something flat, but it becomes an issue on fretboards where the radius requires a thicker blank.

0.024" is fine for thinnest section on shell, the thinnest I've made lines was ~0.012 but that was really on the edge when using a full-thickness (0.06") blank. The material itself has trouble holding together once it gets too thin.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Bob--Have you had any luck with trying to run the tiny endmills deeper than their flute length with multiple passes?
I get by with this cutting ebony with, say, 1/16" diameter endmills but I suspect the micro-miniature endmills don't tolerate this well?
Thanks
Nelson

Bob I am curious as well and in addition, I am curious about feedrates??? I know you run a real machine and want to ask if you have any experinece with lesser machines and the vibration that most of them have???

Mike

Nelsen: Depends on the cutter. I take multiple passes on shell. The cutters I use have flutes all the way to the top of the max cutting depth (before it tapers out to 1/8") but I've tried to get cutters that only had flutes up to the pass depth I use before. The cost of the custom cutters was prohibitive compared to the theoretical benefits so I didn't go through with it. I have run 1/16" cutters deeper than their flute or max cutting depth (letting the taper 'cut') on occasion, but you need to make sure the taper rubbing isn't going to stall the cutter or damage the work.

Mike: I use cutters from PreciseBits and they have feedrate recommendations on their website for their cutters. That'll get you started. So far as the machine I think the main thing you need to worry about is runout. You'll be moving the cutters slowly, anyhow, so motion smoothness isn't a huge deal but a little runout hurts a lot. A sub-spindle with less runout like one of the Wolfgang ones or an Air Turbine Tools spindle will go a longer way to avoiding cutter breakage than a smoother-running machine! Bonus is they'll both give you more RPM, too, which helps a lot.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Chris I have the logo done, assuming it can be cut. Some of the entities only measure .023" wide. Take a look.

Mike