Hi Colin,

I'd gone for one of those from linearmotionbearings2008, and have just got it working. Pleased with it so far, although not ready for cutting yet. Chai is prompt with replies to emails.

After much research it would seem they don't need much cooling at all. A mere 20 litres / hours is all, which is tiny compared to a windscreen pump of 200 litres / hours or CPU water cooling pump of 500 litres / hours. Simplest solution, tried by several people, is using 5 litres of water in a metal bucket, hooked up to a small aquarium pump. Relies on passive cooling and works well by all accounts.
I'm planning to add a digital temperature readout to my cooling circuit (~£5 ebay). Might be possible for someone clever to link this to an over temperature estop in Mach3, but that is for another day.

Here's my build log so far:
http://www.mycncuk.com/forums/showth...upgrade!/page2

If this puts you off, there is always the aircooled option, although these are lower max power, and are a bit noisier (fan) but still nothing like a router.

Don't forget you also need an invertor to drive them. I went for a German VFD (Moeller), but Hitachi are also popular. I didn't fancy the Chinese VFDs after reading about quality problems with them.

Hi Mike,
The speed for the Chinese spindles is similar to a router, so the advantage for me is the low noise levels. They also claim a very low runout.