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I use up to a 1/8" bit, although I think it's hard on the turbine to run the 1/8". You can run a Fadal up to 600IPM, as the feed rate pot goes (and works) up to 150%. The older Fadals (all pre-1994, I believe) had smaller imperial ballscrews and were slower.

There are other factors to feed rate as well. Eventually the beam strength of the cutter comes into effect, as well as how much it heats up per cut. On small cutters, you really can't increase feeds too high or the other stresses besides chip buildup will snap them. 6x the cuts means heat builds up 6x as fast, and 6x the feed means 6x the lateral stress.

Good advice those last two lines. My favourite feature of the Fadal control, which a lot of newer mill controls lack, is a hardwired feed rate pot. Every time I proof a program I stand there with my hand on that pot and figure out the perfect feed rate (which is then coded into the program permanently).

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

What's the deal with Rhino and CAM? I was looking on Rhino and it looks like I would have to buy a 3rd party cam product, is that true? What does everyone use for that?

Rhino is a CAD only program, though I claim the best such program at any price.

As for CAM, there are two popular plugins for Rhino that do the trick. RhinoCAM is essentially VisualMill Basic, but operable from within Rhino. MADCAM is another Rhino CAM plugin, and it's pretty spiffy as well.

If you go to secondary software then there're a load of options out there. On the lower end in price you have Visual Mill (which I quite like) and BobCAD (which I don't really like, but they sell a lot of copies). From there it zips up and up in price until you hit MasterCAM, GibbsCAM, and the other big CAM players.

I use MasterCAM, but wholeheartedly recommend Visual Mill. I also used MADCAM for some time, but it's been awhile so I can't say yea or nay on it, though 3.0 was a good piece of software and relatively affordable as well.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Bob, RhinoCAM is a form of Visual Mill made as a plug-in for Rhino CAD.

Isn't that what I said?

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

[QUOTE=EricKeller] What's the deal with Rhino and CAM? I was looking on Rhino and it looks like I would have to buy a 3rd party cam product, is that true? What does everyone use for that?
[/QUOTE]

I use Rhino and RhinoCAM for my home shop and am very impressed with both. I use Solidworks, Rhino, and MasterCAM at work and I can do a lot of the same things at home for a LOT less $$.   

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http://www.PeakeGuitars.com

I just got a quote for Solidworks, and the package I would want would be $4000-$8000. Top end would have the engineering packages, so I could probably make my money back with that, but that's still enough money to choke a horse. Plus the maintenance was most of $1k a year.

So Rhino does look like a good deal if I go with the educational package at $200. But I see that Rhinocam basic is $1000. Hmm.

Bob, yes, that is what you said; I kluged earlier confusion and your name by mistake.

CAD/CAM is still either a hobby unto itself for a really small shop, OR you have a CAD background and so the learning curve won't be too bad, OR you have a small production operation and you really do need to make multiples of parts.

It's taken many hours for my CAD/CAM guy, Matthew Tolley, to tool up our most difficult part to date...our double stiletto bridges.   It's a very 3D part with several spots that very easily blow out.   I can make them on a pin router with some hand work in about 40 minutes...not too bad for how tricky it is.   Matthew has got it down to 20 minutes on the CNC machine; they are really beautiful; they need hardly any 220 sanding; and they have tooling holes in the bottoms that we'll eventually be able to use for locating pins.   They are significantly better than what we got in the past from NC solutions.   At 18 to 24 of these a month, that will be a good day and a half a month less labor going out here. There are three vacuum fixtures, bottom, top, and tilted saddle slot, and each fixture holds three bridges, so this thing can run for a full day, get out 24 bridges, and maybe we'll have an hour and a half of labor into them.   

Our philosophy on the machine is that machine run time is practically irrelevant if it saves sanding labor and makes for more accurate assembly of parts.   I wouldn't care if it took an hour per bridge instead of 2/3 of that in my time. The machine is doing that work all on it's own, and at about $300.00 a week in lease costs, it's cheap. I can't wait to see it working six to eight hours a day, every day of the week.   

I cut my bridges very similar to Rick and do a tilted saddle as well, I have one jig with vaccum and I start with index holes in the top (they are very shallow), round the bottom and add a lip for finish. Then flip it over (the machine cuts a set of index holes for me) do the top, do the string holes (two are open to the bottom for vaccum), then I cut the string slots with a smaller bit and finally move it to the tilted jig to do the lean back cut on the saddle.

Took me forever to figure that out and get it working, but I can kick a full one out in about 30 minutes now if needed. I've learned that very curly woods need to have steps cut into it or it will tear out, that's my latest change but an easy one.

Eric, Rhino and RhinoCam are great products, the people who built where AutoCad sales professionals who got tired of mokeying with it and wrote their own, they started with a viewer and ended up with what we use today. They still teach some AutoCad courses in fact, but Rhino is a better deal and I would argue just as powerful as anything else out there for less money.

-Paul-

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-Paul-

Patriot Guitars

There's also Moi3D, written by the guy who originally coded Rhino for McNeel. It's coming along well, uses the same file format as Rhino, and moving from one to the other is pretty simple I find. It's also a pretty powerful program and in free beta right now.

Also, MecSoft, who make VisualMill and RhinoCAM, are offering something called FreeMill right now which is free and will make toolpaths for you, albeit limited ones.

If you wanted to, you could make stuff in Moi, for free, and then make toolpaths in FreeMill, for free. Moi is a bit weaker than Rhino but has more or less everything you'd need to do guitar stuff, and FreeMill doesn't do nice things like contour toolpaths, but you could get by with them if cash is tight.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

if money is tight, don't get into CNC!

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http://www.PeakeGuitars.com

[QUOTE=Parser] if money is tight, don't get into CNC!

[/QUOTE]

No kidding! It's a slippery slope if ever I've seen one.....even more than building guitars for a hobby!

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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."

[QUOTE=Parser] if money is tight, don't get into CNC!

[/QUOTE]

Hahahahaha... A Truer statement was never said...

Some builders treat machines like the K2 as hobby machines because we aren't taking out three mortages to buy them! I don't find that to be true at all, my machine is solid, has performed well (even when I've crashed it) and has acceptable tolerances. The price *was* attractive but I would not have purchased it had it not met my needs.

To this day I would love to have a little desktop machine just to do inlays. I would not consider it hobby at all, but something I could easily make money on.

It's all a matter of perspective :)

Cheers

-Paul-

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-Paul-

Patriot Guitars

[QUOTE=Sprockett]
To this day I would love to have a little desktop machine just to do inlays. I would not consider it hobby at all, but something I could easily make money on.

It's all a matter of perspective :)[/QUOTE]

Build one!

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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."

Your a funny guy Williams....

I can't afford one right now, but at some point....

-Paul-

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-Paul-

Patriot Guitars

Yeah! Me neither!

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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."

my wife is starting to get on my case now. Apparently I promised that I would start a business and make some money...or something along those lines. If only I could sell sawdust...

I'd offer to cut some stuff for you guys..but it would be preaching to the choir. How about some surfacing work? I can do some Rhino surfacing work if you need it...I'll take any work...just make her stop!

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http://www.PeakeGuitars.com

I'm thinking about saving all my wood dust by species and making exotic hdf to sell. Just think, Brazilian Rosewood high density fiberboard. I'll bet you could build guitars with that...

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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."

Don, maybe you could make extruded linings.  BRW solid extruded linings - custom shaped for specific designs.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

There you go!

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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."

[QUOTE=Bob Garrish]Good advice those last two lines. My favourite feature of the Fadal control, which a lot of newer mill controls lack, is a hardwired feed rate pot. Every time I proof a program I stand there with my hand on that pot and figure out the perfect feed rate (which is then coded into the program permanently).[/QUOTE]

That's a cool idea!

I meant to ask Bob, what kind of Air turbine you're using?  I burned out the bearings in my Air Turbine Tools unit years ago and never replaced them.  I just fell out of love for the idea of using a 4 hp compressor to power a 1/32" bit.

[QUOTE=Sheldon Dingwal] I meant to ask Bob, what kind of Air turbine you're using? I burned out the bearings in my Air Turbine Tools unit years ago and never replaced them. I just fell out of love for the idea of using a 4 hp compressor to power a 1/32" bit.[/QUOTE]

I get mine from them. I don't know of any other companies putting out precision turbine spindles for machine use. Not many other good ways to get a mill to 65000 or 90000 RPM.

Their service is amazing, when I sent mine in to be repaired it went back in the mail to me the same day it arrived there. The feed rates I'd have to use with 1/64" bits at 10000 RPM would be unacceptable, so I let my compressor suffer. The 5HP compressor is using less juice than my 10HP spindle anyhow.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services