Quote Originally Posted by Lee Roberts View Post
Hi Thomas,

I think when all said and done these motors/spindles are just a typical DC motor, so you can just give them 12-48v and your away.

I would imagine then that you can just vary the voltage supplied, to control the speed, you may be able to do this with a controller depending on what you've got, however it may just be better to get/use a standard type potentiometer where you control the speed manually.

I say the above because to be honest I wouldn't bother to invest any time or energy in one of those spindles, they work yes (they hold a cutter and spin) but their not really up to much at all, not sure if you've noticed or not but they are fitted with an ER11 collet, that's going to limit you to very small cutters for a start.

If your looking to fit it to one of these £4-500 Chinese machines, then yeah pop it on the machine and crack on making dust as you've nothing to lose.

If it's going on a machine that is much more capable then that is when I would say don't bother, the machine will be capable of more than the spindle will like and you'll just kill it or be limiting yourself/machine, it will just end up being a false economy is what I mean to say.

If you consider what is involved with adding a spindle to a machine (properly), it would be a much better investment of everything to use a more worthy spindle to start with.

The best price I can find a 2.2k water cooled spindle and vfd for is £180, they've sold lots, comes with a 2 year warranty but more attractive is the quote of 4 quality bearings in the spindle:

http://www.ebay.co.uk/itm/170746857178

I haven't ordered from them yet but I will be soon and I'm pretty positive that's who I will buy from, they do have negative feedback but I couldn't find any that related to this item.

As I said these spindles do work, here is a video of one actually cutting something:

https://youtu.be/6v534cJNzrU

.Me
A PWM speed controller would be much better for a DC motor. You will struggle to find a resistor that is rated high enough wattage wise to limit the current. Also, reducing the voltageis not a good idea as it will shorten the life of the motor. You're on the right track though.