Collet accuracy / tolerance ??

[Greg Parrish]

How accurate of a collet can the Axiom 3hp spindles really benefit from? I'm looking to add another size and see that I can find them with accuracy to 0.0004, 0.0002 and 0.0001 with increasing prices of course. But I don't find anything in the axiom specs that lead me one way or another. Thanks.

[Jim Becker]

A good collet setup is beneficial even in "less critical" cutting. Collets are also "wear items" and should be replaced periodically or if you drop them on the hard floor. Most of the collets I use are Amana, but there are some other good choices. I have multiple collet nuts for convenience, too. Those nuts came from Maritool (https://www.maritool.com/product_info.php?products_id=47). The link is for ER-25 that my spindle uses, but you should buy collets and nuts with the correct ER designation for your particular spindle...likely ER20 or ER25, but check first. The extra collets and alternative size collets I bought came from ToolsToday.

Collets for spindles are available in a wider variety of sizes than for regular routers. I have a few 3/16" cutters and have a 3/16" collet to match. While I mostly use .25" and .5", my .375" and .125" get use, too.

[bobby milam]

What are you going to be using them for? I do a lot of 2.5D carving on plaques and such. I ordered a cheap Chinese set off of Amazon pretty cheaply and they work perfect for me. At the moment I have found no reason for buying any of the higher priced ones. I mainly only use 1/2, 1/4 and 1/8 at the moment but I do have some 1mm bits that I need to order some collets to fit.

[Greg Parrish]

General wood cutting like the hardwood cutting board and sign I posted, as well as eventually some 2.5D and 3D carving.

The standard collets rated to 0.0004 accuracy seem most affordable. That’s what the Amana ones are. Just didn’t know if it paid to go for more precision. Thanks.

[Jim Becker]

Unless you're machining metal to high tolerances, those "standard" collets should be just fine, especially if you take care of them.

[Greg Parrish]

Unless you're machining metal to high tolerances, those "standard" collets should be just fine, especially if you take care of them.

Thanks. I ordered the ones from Maritool that you linked above. They were reasonably priced and claimed tolerance to 0.0003. Also, picked up a spare collet nut. Thanks again.

[Bruce Page]

I get my collets from Precise Bits. I typically order precision grade, .0004 TIR. I use the .250 collet 80% of the time so it gets replaced every few months.

[richard newman]

Have you checked your spindle internal taper for runout? Unless it's less than a few tenths, theres nothing to be gained with a .0001 collet. If it is runout you may be able to correct it by the orientation of the collet in the spindle to cancel error if it's important to you.

The Precise Bits website has good information on acceptable runout. It's pretty much proportional to the diameter of the bit. For pearl inlay on my banjos I use bits down to .015", which requires really low runout, no more than a few tenths, or the bits break quickly