DIY spindle design

[Jeremy]

Total cost to date is about £60, not including the 12V 30A power supply that I already had. Similar power supplies cost about £25 to £30 via ebay.

This is strictly a one-off for my router build. I'm after something that will spin at a reasonably high speed so that I can use small diameter tools, but don't really needs lots of power, as it'll only be cutting light stuff. Mind you, I suspect that the few hundred watts that this little unit will deliver should make it pretty powerful for it's size. If anyone want more power, the place I purchased this little 550 watt motor also sells some nice 2800 watt model motors for around £30 each. I have a few for another project, the snag being that they draw around 80 amps each, so need fairly hefty power supplies.

I also wanted a fair degree of accuracy, without the fairly horrid run-out that Dremel-like tools have, as I'd like to try using it for milling PCB's as well. So far I think I'm on-track to have a fairly solid little spindle with relatively good accuracy, probably better than a thou TIR.

Jeremy

[philbur]

Small cutters really need much better than a thou TIR. Better than a tenth would be much more suitable. Otherwise the necessary low chip load per tooth will leave you cutting on one flute only. A decent level of precision in the bearings is called for, together with good adjustment for preload. No-name deep grove bearings of unknown class may not get you there. The other killer will be the concentricity of the spindle taper with the bearings seats.

Get these two points right and you are on a winner. Get them wrong an it's going to be a so-so spindle.

Just some thoughts
PHil

PS: I haven't read the whole thread so if I missed something sorry.

So far I think I'm on-track to have a fairly solid little spindle with relatively good accuracy, probably better than a thou TIR.

Jeremy