Pillar drill stepped pulley and belts - UK Vintage Radio Repair and Restoration Discussion Forum

ToneArm · 1st Oct 2015, 8:32 pm

I got a nu tool pillar drill missing its motor on ebay, it looked very much like the one i have already but with a nice rack and pinion mech on the table. When i picked it up it turned out to be a much bigger machine, and a definate step up in quality from my old one. No model or serial number to be found, but it looks similar to a n-7b but with a square table not round.

I have found a suitable motor that mounts and lines up nicely, however i am not sure how to specify a pulley and belts. Can someone give me some pointers to measure the existing pulleys and work out what's needed please.

It looks like by the time i finally get it working i could have bought a fully working one as these go pretty cheaply second hand. At least i can make it a learning exercise...

Thanks
Glyn

Station X · 1st Oct 2015, 8:54 pm

This may help:-

http://www.beltingonline.com/a-secti...alculator-8405

I assuming the belt is of 'A' cross section. Most of these I've fond on machine tools are. Check here:-

http://www.beltingonline.com/vee-and...g-v-belts-591/

ToneArm · 1st Oct 2015, 10:06 pm

Graham, thanks for the links.
Regards glyn

John_BS · 2nd Oct 2015, 5:31 pm

Glyn:

From my limited experience of buying pulleys & belts, the costs do mount up!

My own pilllar drill tends to stay on one (lowish) speed* for 98% of the time, so it may be more cost-effective in the short-term to buy one (single-diameter) motor pulley and matching belt untill such time as you happen upon a multi-speed pulley (= the inverse of the quill pulley).

John

* 600 -700 rpm.

Station X · 2nd Oct 2015, 6:13 pm

Any new stepped pulley will need to be similar to the existing one, but will need to be mounted the other way up.

Picador used to be the source for this sort of thing, but I think they went out of business.

Plenty of stepped pulleys on eBay, but you may have to find someone who can bore the centre to the correct size and if necessary broach a keyway in it.

ToneArm · 4th Oct 2015, 8:08 pm

Tried to take the intermediate pulley and use it on the motor shaft but it was just too small to make the swap. It had roller bearings so opening out not an option. I just ordered a single 2 inch pulley for nine quid, John. That will get it spinning and I can still change speeds on the intermediate pulley.
Cherrs
Glyn

1st Oct 2015, 8:32 pm	#1
ToneArm Pentode Join Date: Feb 2015 Location: Conwy, Clwyd, UK. Posts: 246	Pillar drill stepped pulley and belts I got a nu tool pillar drill missing its motor on ebay, it looked very much like the one i have already but with a nice rack and pinion mech on the table. When i picked it up it turned out to be a much bigger machine, and a definate step up in quality from my old one. No model or serial number to be found, but it looks similar to a n-7b but with a square table not round. I have found a suitable motor that mounts and lines up nicely, however i am not sure how to specify a pulley and belts. Can someone give me some pointers to measure the existing pulleys and work out what's needed please. It looks like by the time i finally get it working i could have bought a fully working one as these go pretty cheaply second hand. At least i can make it a learning exercise... Thanks Glyn

1st Oct 2015, 8:54 pm	#2
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,289	Re: Pillar drill stepped pulley and belts This may help:- http://www.beltingonline.com/a-secti...alculator-8405 I assuming the belt is of 'A' cross section. Most of these I've fond on machine tools are. Check here:- http://www.beltingonline.com/vee-and...g-v-belts-591/ __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

1st Oct 2015, 10:06 pm	#3
ToneArm Pentode Join Date: Feb 2015 Location: Conwy, Clwyd, UK. Posts: 246	Re: Pillar drill stepped pulley and belts Graham, thanks for the links. Regards glyn

2nd Oct 2015, 5:31 pm	#4
John_BS Octode Join Date: Dec 2008 Location: Wincanton, Somerset, UK. Posts: 1,784	Re: Pillar drill stepped pulley and belts Glyn: From my limited experience of buying pulleys & belts, the costs do mount up! My own pilllar drill tends to stay on one (lowish) speed* for 98% of the time, so it may be more cost-effective in the short-term to buy one (single-diameter) motor pulley and matching belt untill such time as you happen upon a multi-speed pulley (= the inverse of the quill pulley). John * 600 -700 rpm.

2nd Oct 2015, 6:13 pm	#5
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,289	Re: Pillar drill stepped pulley and belts Any new stepped pulley will need to be similar to the existing one, but will need to be mounted the other way up. Picador used to be the source for this sort of thing, but I think they went out of business. Plenty of stepped pulleys on eBay, but you may have to find someone who can bore the centre to the correct size and if necessary broach a keyway in it. __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

4th Oct 2015, 8:08 pm	#6
ToneArm Pentode Join Date: Feb 2015 Location: Conwy, Clwyd, UK. Posts: 246	Re: Pillar drill stepped pulley and belts Tried to take the intermediate pulley and use it on the motor shaft but it was just too small to make the swap. It had roller bearings so opening out not an option. I just ordered a single 2 inch pulley for nine quid, John. That will get it spinning and I can still change speeds on the intermediate pulley. Cherrs Glyn