Bosch PBD 40 bearing upgrade

[th1980Participant @th1980]

I have a Bosch PBD 40 drill press. One of the common reported problems with it is the upper bearing of the drill shaft. The original from factory is a needle bearing and it has a lot of radial play in it. The suggested replacement is either an 8 mm high 8×12 mm bronze bushing or two 8x12x3.5 mm roller bearings stacked on top of each other. I have bought both options but I’m not sure which one would be better for the job? The bushing has graphite lubrication inserts in it. The bearings look a bit flimsy and they are tiny.

[DiogenesParticipant @diogenes]

How do the deficiencies of the standard bearing affect the work that you ask of the drill?

 

[th1980Participant @th1980]

There is a noticeable sideways play in the drill chuck. I would like to reduce that.

[Michael GilliganParticipant @michaelgilligan61133]

At the risk of being branded a boring old ____

They don’t build ‘em like they used to !

https://www.mtmc.co.uk/product.aspx?ProductID=162581&SKU=BSD-1600A000SR.A5

MichaelG.

[gerry maddenParticipant @gerrymadden53711]

I’d go for the unit that gives you the best spindle stability/minimum free play.

[Michael GilliganParticipant @michaelgilligan61133]

With subtitles in English:

.

https://youtu.be/olqs1MNOg2g?feature=shared

.

MichaelG.

 

[gerry madden]

On gerry madden Said:

I’d go for the unit that gives you the best spindle stability/minimum free play.

And which one would that be? I have no idea myself.

There are videos in Youtube with both options installed. I suppose either one will work but being a bit of a perfectionist I would like to use the best option.

[DiogenesParticipant @diogenes]

Could be that their drill spindles are designed to perform under dynamic conditions and axial pressure – and what happens when it is limp and static may not be a reflection of the true picture..?

[gerry maddenParticipant @gerrymadden53711]

And which one would that be? I have no idea myself.

Assuming the companion parts are suitably dimensioned, my preference would be for the rolling element bearings. The video seems to confirm these are a good choice.

[old martParticipant @oldmart]

I would opt for the ball races first, but keep the bronze bush just in case it is ever needed.

[th1980Participant @th1980]

OK, I shall try the bearings then. Thanks for the answers.

[Howard LewisParticipant @howardlewis46836]

Since the thrust on the spindle will be axial, the ideal would be a taper roller bearing. The thrust will minimise any eccentricity

Ideally taper roller bearings at lower and upper ends of the spindle, with a light preload, say 0.05 mm

Howard

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