Clarke pillar drill, centre main bearing gets hot!

[Andrew TinsleyParticipant @andrewtinsley63637]

A friend of mine has a 12 speed pillar drill, Clarke badged. It is the sort that has 3 pulleys.

Drilling a few holes in Perspex made the centre main bearing run very hot! The cast iron block (?) which supports the three pulleys was getting hot in the middle and I assume this is because the centre bearing is bad.

A quick look at the offending item, gave no signs of any lubrication points, indeed it looked as if getting the centre shaft out of its bearing housing was not going to be easy. Can anyone throw any light on what type of bearing this would be? Or is it likely to be a shaft in a reamed hole in the block! Before I attempt to dismantle it, I would not mind some more info.

Thanks,

Andrew.

[Andrew TinsleyParticipant @andrewtinsley63637]

[Ian ParkinParticipant @ianparkin39383]

Best thing to do is to remove the centre pulley turn the motor pulley the other way up and then fit a longer belt and then have 8 speeds or so…less adjusting and wearing parts and noise too

Edited By Ian Parkin on 12/06/2017 21:06:40

[Nicholas FarrParticipant @nicholasfarr14254]

Hi Andrew, the floating pulley should just lift out of the hole in the bottom of the belt guard. The pulley is mounted on the swivel with a ball bearing, it is most likely to be a press fit in the pulley and the swivel stub, items 18,19 and 20.

Regards Nick.

Edited By Nicholas Farr on 12/06/2017 21:32:20

[Andrew TinsleyParticipant @andrewtinsley63637]

Thanks Nicholas!

The exploded diagram looks to be the information I am after. I did not realise that the centre pulley is on a crank! Makes me wonder what could possibly cause so much heat to be generated? The drill has had very little use as my friend would normally use his mill for drilling. In fact I doubt he has ever changed the speed! he is not exactly very savvy when it comes to things mechanical!

So I must assume the ball race is the culprit for the excess heat, at least it looks simple to change, contrary to my first quick impression.

Thanks again,

Andrew.

[Bob StevensonParticipant @bobstevenson13909]

Does it actually HAVE a bearing?………My Aldi drilling machine just has a steel collar for the idler pulley and shortly after I started using it seized solid in mid drill…… I jsut made some crude oil channels in the collar and simply give it a squirt of oil every now and then. These are extremely inexpensive tools and my feeling is that one needs to do as little as possible to them until they inevitably fail and are simply replaced…….to bore out the collar and fit ball races would be a good improvement, but it's kind of against the spirit of the 'Chinese Cheapy' philosphy…..for me anyway!

[Andrew TinsleyParticipant @andrewtinsley63637]

I have done a strip down and found the eccentric shaft to be a sloppy fit in the pillar drill, top block, however this doesn't rotate. The ball race that connects the multi step pulley wheel to the other end of the eccentric shaft is in good order. I put it all back together for some trial drilling. Guess what, the centre portion of the top block got quite hot.

Checking the bearing's temperature revealed that it was about the same temperature as the centre of the block! I give up, I cannot see why there is so much heat generated and where it is coming from.

Andrew.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Andrew Tinsley on 15/06/2017 18:02:23:

I have done a strip down and found the eccentric shaft to be a sloppy fit in the pillar drill, top block …

Checking the bearing's temperature revealed that it was about the same temperature as the centre of the block! I give up, I cannot see why there is so much heat generated and where it is coming from.

.

Just guessing …

The eccentric shaft is a sloppy fit, and therefore the pulleys are canted over [by the belt tension] and therfore the belts are scuffing … That causes heat to be generated throughout the locality.

MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Andrew Tinsley on 15/06/2017 18:02:23:

I have done a strip down and found the eccentric shaft to be a sloppy fit in the pillar drill, top block …

Checking the bearing's temperature revealed that it was about the same temperature as the centre of the block! I give up, I cannot see why there is so much heat generated and where it is coming from.

.

Just guessing …

The eccentric shaft is a sloppy fit, and therefore the pulleys are canted over [by the belt tension] and therfore the belts are scuffing … That causes heat to be generated throughout the locality.

MichaelG.

[Andrew TinsleyParticipant @andrewtinsley63637]

Hello Michael,

It did occur to me that the whole caboodle may be canted. However on checking with the tops of the first and final pulley, the centre pulley seemed to be pretty upright! It is a mystery to me although itdoesn't get hot enough (quite) so that you cannot keep your hand on it.

Thanks,

Andrew.

[Michael GilliganParticipant @michaelgilligan61133]

Sorry … my guess wasn't really worth double-posting.

MichaelG.

[Author]

Posts