If you go down the spindle motor route it would probably be better to use that for the spindle rather than have it drive a separate spindle.

But one would work mounted pointing up at the back of the machine a bit like this with a simple clamp type arrangement to hold the spindle motor body which they often come with.

They do make a lot more noise than a sewing machine motor.

Don’t understand the the bit about a faff to set up, been using mine in all modes for close to 30 years and if it take a whole minute to swap things round I could be exaggerating and lets face it how many times do you have to do it?

Why not just fit one of these:

https://www.proxxon.com/en/micromot/28472.php

I have one fitted to the head of my little cnc mill, primarily for engraving, and find it very good. I have also used it for high speed drilling where the mill’s top speed is inadequate.

Russell

Indeed, my CNC mill max speed of 5000 rpm and that’s really much too slow for small drills and cutters, I’d like 20,000.

On 26 July 2024 at 12:03 John Haine Said:

Indeed, my CNC mill max speed of 5000 rpm and that’s really much too slow for small drills and cutters, I’d like 20,000.

I understand the maths behind these super-high speeds, but I must question the necessity.

… generations of of watchmakers produced magnificent work using a hand bow.

Not arguing, just bewildered.

MichaelG.

.

Edit: Nice example … albeit only drilling a brass plate

https://youtu.be/UqXKpWYo3vI?feature=shared

.

The reason for high speed Michael is to minimise the tooth load.  All too easy to break small cutters rotating too slow.  E.g. for PCB isolation routing I have to limit the feedrate and it takes ages to make a board.

And back in the day when their drill bits were probably just carbon steel they could not be run as fast as HSS or Carbide even if they had a fast elbow.

I recon he is getting over 1000rpm out of that setup.

If you say the pulley is 6mm dia and the travel of the bow 200mm that is 10 turns per pull

I can count about 18 pulls in 10 seconds so 108 pulls per min.

108 x 10 = 1080rpm.

On 26 July 2024 at 14:20 Roderick Jenkins Said:

These motors seem to be back in stock:

hebdenmotorbits on ebay

I use one to drive my lathe toolpost milling spindle and it would fit very nicely on the back of my Pillar tool

 

Rod

 

 

The controller in that ebay listing is deadly. exposed terminals and no earth.At least you put yours in a plastic enclosure.

Hi Martyn

I maybe misunderstanding what advice you are looking for, but in the March 2024 MEW, there was an article, Fifty Years of George H Thomas Universal Pillar tool Part IV  where the author,  Warren Williams,  describes an “integral  variable speed drive for the sensitive drilling attachment”  … “using a 24V DC motor … fitted to millions of electric scooters”

Tony

I built the GHT sensitive drill and drive it via a small 3ph parvalux motor and small inverter.

I don’t use it often but when I do the change over time is minutes.

It did take a bit of careful aligning to make sure the round belt didn’t keep coming off the pullies though.

I did also make the staking part as well but hardly ever use it. The tapping part of the tool though is always used and no way would I want to be without it.

I have some less than ideal electrical setups in my workshop but that motor and controller and mains lead being sold on ebay frightens me!

No warnings or advice on the listing to alert the purchaser that the motor wiring is a mains potential. I know there is label about earthing (as in Rod’s reply), but in one of the ebay pictures the earth lead is just shown unconnected.

We know that putting the controller in an enclosure is straightforward but how many buyers will properly protect the red/black motor wires from where they exit the motor endplate to the controller I wonder.

Ian P

Tapping chuck design comes with the courtesy of Mikes Workshop.