Anyone know of a small high speed spindle that would be suitable for attaching to my mills quill. Only for engraving so doesn't have to be that powerful and small size and reasonable cost would be a big advantage. Looking for around 20,000 rpm and variable speed is not needed.

Hood

For engraving?  For straight line engraving I use a non spinning spring loaded engraving point.  There are several on Ebay.  Used to be there was only one for about $179 USD, but there is now another cheaper one.  I got mine from one of the guys on the Zone.  Now that I have seen his I could make one on my lathe easily enough.  The hard part is finding just the right spring.  Depending on the point chosen (or made) it works on a variety of things.  I have even used it to engrave the curved side of relatively large sockets to see how far I could push it.  

What are you engraving?  I found this type worked very well with a sharp carbide point on steel or hard aluminum, but for plastics a rounded point worked better and "pressed" or embossed in the marks.  You can also get diamond tips for engraving really hard stuff like glass.  

If you are routing out you can get a Harbor Freight flex shaft tool with a handpiece with chuck that will handle .125 shaft bits for about $50 USD and it only has a couple thousandths side play.  I can't feel it in mine.  It free spins about 15,000 rpm, but if you load it down with deep passes it slows down.  I have two of them and I sometimes use them in my mill with a home made bracket that holds two of them so I can destroy two work pieces at a time.  I hang the motor on the wall and clamp in the handpieces.  They actually have less sideplay than the $50 Foredom (no motor included) hand pieces, but for a lot of work the $135-$150 Foredom 25 continuous duty handpiece would be better because it has bigger bearings and sideplay down around .0015.  

If you are hogging out larger lettering in wood then the cheapest thing that's halfway decent is probably a Makita Router and your own mounting bracket.  Thei trim router turns about 28,000 RPM.

Thanks Bob,
What I am doing is I suppose V Carving in Alu and possibly stainless and also want it for PCB prototyping.
So spring loaded is not wanted and end float in the spindle has to be minimal as the max depth I am going is 0.5mm.
Will have a look at the flexi stuff you mentioned. A router was my first thought but really its too bulky, would prefer something small, preferably that I could fit half way into a 40 taper spindle.
Below is the type of thing I am wanting to do, this took 3hrs and if I could get the spindle up to 20,000rpm it would take under half an hour.

Hood

Side play and runout can be a much bigger issue when using smaller bits.  That looks almost like lithograph type work there.  I think I would be tempted to go with the Fordom 25 with one of their motors.  It only claims 1/5 HP, but its a true 1/5 HP and it turns 18,000 rpm.  Either that or there is a guy selling a high speed spindle and motor on ebay that claims very low runout and side play.  He claims people are using it with bits and mills so small you might break one just looking at it.  

Do not get a Foredom 44T or 43T handpiece thinking to save a few bucks and compromise.  They are intended strictly as a hand carving tool holder and they have looser tolerances and looser bearings to reduce heat build up.  I know.  I already tried them and I was unhappy with them for a spindle on my machine.  Go with the 25 if you go that way.  If you want to go cheap the HF ones are tighter tolerance than the 44 or 43, and yes they do build up some heat at full speed.  

Also, the Foredom 25 comes with self centering collets instead fo a chuck.  Slightly better consistency that way. 

I've heard great things about the Kress spindles, but I don't think it's as small as what you're after though 

Dave

Thanks guys,
 cant seem to find anything decent in the UK for the flexi type but have found some Kress ones which look promising but a bit expensive. Then again the only place I have found so far that has them is well known for top flight prices.

Will keep searching.

Hood

Have found some Kress ones which look promising but a bit expensive. Then again the only place I have found so far that has them is well known for top flight prices.

Will keep searching.

Hood

Welcome to the World Of CNC 

Have you though about a die grinder, they can be bought quite cheaply on that well know auction site

Hi Phil,
yes have thought about die grinders but not sure what the end float and runout would be, any ideas?
 Suppose if the worst came to the worst I could make up a short spindle  and just use the grinder for  driving it.


Hood

Hi Hood,

I think i paid £20 for mine from that well know auction site it has no discernible end float.

It is quality Taiwan not cheap Chinese rubbish.

LOL,
 link? Name?

Hood