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Tenson
26-10-2015, 07:30 PM
My pillar drill was worn out so I pulled all the bearings off and ordered new ones. However I note the bearings were really bloody tightly on there originally so I won't be able to put them back without using my bearing puller. Now I can do that for some of them but not all; one is right down the end of a long rod and the puller won't reach it.

I was wondering if they are put on with heat so the inner race of the bearing expands. What kind of temp could I heat the bearing to without worrying about melting the grease? 50C? It's a 6201-2RSH SKF bearing with plastic covers.

Is this the method they probably used when building the drill in the first place, or did they just use a lot of force?

EDIT: SKF induction heater has a standard temp of 110C, but they did not use a pre-greased bearing in the video.

Lee Roberts
26-10-2015, 08:09 PM
If you get a small and sharp/pointed item, you should be able to pop the rubber seals off the bearing safely, as they more or less clip into place.

Then you can just re-grease them, I would clean the grease out before you heat, when you do re-grease, try not to over pack them, basically where you have open space around each ball bearing, just try to lightly fill that void, over packing a bearings can hinder it's performance and life span.

.Me

Tenson
26-10-2015, 09:21 PM
Thanks for the reply. I actually just tapped them onto the shaft. It wasn't as difficult as I thought it would be.

However... once assembled it has a clunky notch feeling as it rotates, just as it did with the old bearings! I thought 'shit I mashed one of the new bearings' so I took it apart again. Not assembled, each bearing feels smooth but assembled it has a clunky feeling as though the outer race has an indent and bumps as each ball rolls over. What's going on here!?

Incidentally, the old bearings feel smooth once removed from the drill.

This is the assembly. The central rod is held inside the outer sheath by two 6201 bearings.

1637216373

Tenson
26-10-2015, 09:25 PM
And assuming I need a new drill - can anybody recommend a good brand for under 100? I don't need a big one, just the standard bench top pillar drill but good quality if possible on a budget!

The one I have is Axminster and probably would have been in better condition now if I hadn't tried to use it as a router sometimes ;)

Lee Roberts
27-10-2015, 12:12 AM
Well i was about to say, "have you checked the spindle shaft for strait, using some rollers" but then i read your last post about using it as a Router...

I would defo check the shaft, as I think you know, a drill press isnt designed for the kind of forces (axial loads) exhibited when used like this, let alone the chuck comming lose and dropping off in mid "flight" taking a chunk out of anything or one standing close by. Standard radial bearings dont like this kind of thing either, I believe it's the reason we use angular contact bearings on our machine leadscrews...or should be :whistle:.

I use a 50 drill press from Lidl, there are a few like it in these types of shop at times, the Lidl one though, is of better quality than the others, dont forget your getting what you pay for at 50. Not sure if they still do this one though as everything they seem to get now is branded "Parkside".

.Me

komatias
27-10-2015, 10:33 AM
A design note here on the selection of bearings. For machine tools it is preferable to use shielded bearings to sealed. Rubber seals add friction and heat to the assembly that you could do without. Shields do not contact the inner race so they do not add too much friction and allow oil to seep through to the balls.

What you are experiencing with the assembly being notchy is probably out or roundness in the housing or some misalignment on the shaft itself.
Should not be difficult to figure out and save a few bob repairing it.

Tenson
27-10-2015, 08:13 PM
I took it apart again and checked the shaft and found it was good and true. So I re-assembled and it ran smoothly. I must have bodged something first time!

Drill back together and it runs quieter and less wobbly now. Sadly still a little bit of runout which I think is from the chuck arbour. Good enough for now and I'm not sure how to remove the chuck as the morse taper is directly on the end of the spindle, meaning I have no way to press the chuck away from the spindle shaft. I don't think it was meant to be removed. It's only a cheap Axminster WD13S (about 90 I think).

Tempted by a Bosh PBD40. Any reviews on this?

Tenson
28-10-2015, 03:39 PM
Does anyone have tips on how to remove the chuck on my WD13S pillar drill from Axminster?

The spindle has a taper directly on the end and pressed into the chuck. There is no 'key way' to release it. Tapping a bearing release fork between the chuck and drill body only acts to pull the spindle out of its bearings.

Perhaps a bit of dis-assembly lubricant and heat on the chuck? Any other tips?

mekanik
28-10-2015, 05:06 PM
If you can lever off the bottom bearing you could try something like this.

http://www.tools-4-you.co.uk/Hand%20Tools/ball_tie.htm

If the bearing wasn't on the shaft a sharp strike to the back of the chuck should break it(the taper not the chuck)

Sorry about that missed the bit where you had tried the taper wedge tried to delete the message but couldn't
You could grip the shaft in the vice just behind the bearing (to prevent it moving) and try the wedge again.
Regards
Mike

Lee Roberts
29-10-2015, 04:46 PM
A design note here on the selection of bearings. For machine tools it is preferable to use shielded bearings to sealed. Rubber seals add friction and heat to the assembly that you could do without. Shields do not contact the inner race so they do not add too much friction and allow oil to seep through to the balls.

Are you sure about that? All the RS type I've played with don't appear to have had an interference fit? Surely if they did the rubber would just brake down and contaminate the balls?

.Me

Lee Roberts
29-10-2015, 05:02 PM
Does anyone have tips on how to remove the chuck on my WD13S pillar drill from Axminster?

The spindle has a taper directly on the end and pressed into the chuck. There is no 'key way' to release it. Tapping a bearing release fork between the chuck and drill body only acts to pull the spindle out of its bearings.

Perhaps a bit of dis-assembly lubricant and heat on the chuck? Any other tips?
Well the wedges method is the preferred way, did you use two either side or just one, here is a link to the correct type, not sure whats going on with the price but I'm sure you can find others or make some: http://www.ebay.co.uk/itm/371117648999

Here is a great video by a friend I follow on YouTube, he's doing a service on a chuck, uses the wedges method correctly and takes you through the motions and more:

https://youtu.be/h_jQ7-UiWgI

.Me