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I'm thinking about jumping off this cliff. I read a bit here and appreciate all the knowledge. I have lots of questions and thought it may be best to separate them in different threads so here's the first.

I've not found much info on choosing a router vs a different spindle. It appears that the expensive spindles are quieter. Any other advantages? Less runout?

I'm imagining doing some jigs with stationing, blind slot fretboards, headplate inlays, some neck work, maybe brace profiling, and rosettes. It seems like a router will work fine for most of that but a higher speed spindle my be better for inlay and fret slots?

What about different mounts for a router and dental tool?

What about collets for the typically used bits? I'm not talking about a machine that can change it's own bits but are there advantages to having something different than a typical router collet?

I have no previous personal experience so simple language is appreciated.

Thanks.

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http://www.chassonguitars.com

I'm still into my first year of CNC too, so take my experience for what it's worth. I started out using a Bosch Colt router and a homemade mount for a high speed "Presto" pneumatic dental handpiece. In order to use 1/8" shaft bits, I got some good collets from precisebits.com. These are very nice collets--much better than the 'factory' Colt collets, but still didn't give me the low runout numbers that I got from the ceramic bearings in the Presto. Not a problem except with things like fret slots--they came out a bit bigger than the bit size with the Colt due to runout, still useable, but a bit wider than expected. Still, the Colt with the precisebits collets gave good results--nothing un-useable.

I bought another machine used, and it came with a Colombo spindle. Huge improvement in all regards. It was much quieter, the runout was next to nil, and its power was pretty incredible for the size. My Colombo is a small one, rated at 1.5 HP, but the power it really generates out does 3 HP routers pretty easily from what I've seen. But, I bought my whole CNC machine for about the price of the spindle alone. Is it worth the difference in price? It depends on what you're doing I guess. I'd have never spent what the Colombo costs if it hadn't been part of a package. I'd have a hard time going back at this point though.

The bottom line to me is this: A good router with a solid mount and better quality collets will probably serve you fine for most instrument making tasks. They'll wear out quicker than a fancier spindle, but they're cheap to replace/repair. Routers will run a lot hotter than a dedicated spindle on long jobs, and they're louder. Not quite up to the precision of a spindle, but good enough for most wood working, including inlay/fret work. Would a spindle be better? Yes. Would it be worth the difference in price? It depends.....

On a CNC machine, I'd concentrate on having a really solid, non-flexing and smooth moving XYZ axis first and worry about a spindle later. The rigidity of the machine itself makes a lot bigger difference on the final work than the spindle does.

I use a PC690router with a super pid2 speed control, using precise bits collets. Since using this I have had no problems with any of these tasks required in guitar building. I very rarely run my router over 14k and can say I can carry on a conversation without raising my voice vs a standard router at speed. Now I have also used spindles and they are even less noisy, but for the $, I can watch the sales from say Grizzly, (This past september) and bought 2 PC690Rs for $89.00ea. I then have replacements to use while changing bearings on the other when needed. Bearings are less than $20 and last about 1500hrs depending on the load. If your spindle needs servicing, this may take awhile as my experience has been changing bearings is not as user friendly and having a spare is IMO not economically sound. so to me having 30mins down time to change routers if a problem comes up is better and a choice I have made that works for me best.

Just my opinion.
MK

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I'm outside looking in, just farther from the window than most.

That's helpful. Thanks.

Quiet is nice but my dust collection is loud enough that I need ear protection anyway so function would have to justify most of the cost.

Banjo, does the Columbo take bits down to 1/8"?

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http://www.chassonguitars.com

Mine has an ER20 collet--you can get ER20s in about any size up to 1/2". I have collets down to 1/16" for mine. A 1/16" will take dental cutters.

Dave

A Colombo or any other spindle will be an ER collet chuck, so they'll take bits right down to 1mm for anything up to ER 40 and you can definitely get 1/8" collets for ER 40. The ER size is one less than the diameter of the collet, in mm, so larger ER ratings mean larger maximum tool sizes but also generally mean larger and slower spindles. Good micro cutters are all 1/8" shank, so you don't need anything smaller. A 1mm ER collet will close pretty much down to zero.

It's a lot easier to change out your spindle than the motion control components of the machine, so the advice to focus first on the mechanics of the machine is good. If you can afford it I don't think you'll ever regret moving up to a spindle- runout on my air turbine spindles drives me nuts and it's minuscule compared to the runout on a router. You can get spindles much cheaper than a Colombo from Keling or various other resellers who'll warrantee them.

((I edited in the Keling line and noticed that the collet question was answered while I was typing...responsive bunch we are!))

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services