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OK, I finally have a small custom CNC table and Mach3 setup. Can someone please give me spindle recommendations. The CNC was originally designed for a Dremel, but I am cutting exotic hardwoods....and need to remove/rough quite a bit.

What is a variable speed spindle......preferably where the speed can be controlled by Mach3......that you would recommend?

I think it needs to be roughly the same size as a Dremel. These Porter Cable routers I see at Home Depot are too big.

What Horsepower, Max and Min speeds, ect?????

ALso, can someone please tell me what speeds and feed rates you would recommend for BOTH roughing AND finish work on Jatoba, Purple Heart, and Rosewood????

What spin RPM on the spindle?

What feed rate (inches per minute) for the feed?

Do you need to give the tool bits a rest so they dont overheat......I.E.....programming them to back off the wood every so often???

Have you thought about a laminate trimmer, such as a Bosch Colt, or a PC?
An actual spindle can be a pretty heavy beast, and finding one that small can be virtually impossible, and would more than likely require a VFD to go along with it. One example is a product sold by HomeShopCNC as seen here. It's pretty hefty, but for a spindle it's pretty reasonable, for a combined price of $1060.00
My guess is that if this cnc was built for a Dremel, it will never handle the weight of a real spindle.
You can also look into air-drive spindles, such as John Hall sells on his Blues Creek Guitars website. While not necessarily great for hogging large amounts of wood, it could probably do a decent job with small stuff.
For inlay work, consider the mini-spindles made by Wolfgang Engineering that are sometimes available in eBay on his ebay store.

As far as feeds and speeds etc, I would offer you the best advice in the world which my friend John Watkins once offered to me...go to the CNC Zone online and read, read, read. Different materials require different speeds and feeds, as well as different router bit geometry. There's more to it than you could possibly imagine, and I haven't even begun to scratch the surface myself. Perhaps John or one of the other CNC guys here can give you some baseline numbers, but it's going to depend a lot on your equipment.

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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--Where in the world have you been hiding this spindle? That's awful close to what I've been searching for. Might require a little heavier counterbalance springs than I use for a Bosch router but that's not a show stopper.
Seems like so many of these compact spindles out there only go to an ER16 collet. Need to be able to handle a 1/2" shank so this spindle with it's ER20 is great! Great price too!
Nelson

Nelson - they've had the spindle for awhile, but only recently added the VFD. If it's at all accurate with minimal runout, it's a great price. But you have to make your own cable to go bewteen the VFD and the spindle. Also, I'm guessing you'll have to make a mount for it as well. It's certainly on my radar for the future if I ever get more heavily back into making guitars again. But right now the PC router is enough to make my backgammon board...

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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."

Feeds and speeds are -highly- setup dependent when you're talking sub-50K hardware. Start with feeds and speeds for aluminum and move things slower or faster from there. There is a LOT of talk about machining aluminum online with all kinds of different setups and it's a good starting point on machining woods (vs guessing).

The type of spindle that might work depends a lot on your machine. Air turbine spindles can work great if you have a load of accurate feed rate to spare, but their only advantage is lightness in a slow or flimsy machine. They're also usually fixed RPM if you want any torque. If the machine's built for a Dremel then you're going to have all kinds of deflection and rigidity issues if you use too much spindle for your machine.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

I was definetly considering the Bosch Colt Variable Speed.......but wanted to know more about the requirements for HP and speed before finalizing.

Can the Dremel work if I put in a 1/8" tool bit and only plunge in 1/8" or so into the wood? I realize that will drastically drag out the cutting time........but I am not a production shop. I am more interested in achieving good results with my limited budget. (Dont have $50k lying around)

The Bosch Colt looks like it will fit and wont be too heavy or bulky for the setup. The body of the carriage and table is made from 1/4" aluminum plate and aluminum extrussions. It isnt bulky and sturdy....but it isnt one of those particle board jobs either.

Is this what you were recommending from Wolfgang Engineering? Why wouldnt this spindle be able to do some roughing with a 1/4" bit? It seems sturdier than a laminate trimmer like the Bosch Colt.

http://cgi.ebay.com/TB-350S-High-Speed- ... 911.c0.m14

Simply because it is only a 1/8" diameter chuck. You can't use this for anything or than small, precise cuts. It's not meant for heavy duty use by any stretch. It's meant for inlay, pc boards and the like.

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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 ended up using the Bosch Colt. It is pretty good, and compact for its power. It is also somewhat cylindrical in shape, which makes it easier to mount than a Rotozip and all those very heavy Porter Cable routers.

it was also only $60 used. The nicer spindles were getting up there between $1500 and $2500.

My Dremel has died twice already. I dont even know what the appropriate use for it is any more......maybe it has an attatchment to hold a feather to tickle yourself with.

You'll have to find a feather with 1/8" or smaller shank.

Turn it down in a lathe, tickling doesn't need much shear strength

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services