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BaronJ
10th Apr 2021, 02:40 AM
Hi Guys,

How to remove a ball race from a blind bore came up on another forum recently which reminded me of a method that I used to remove one.

I turned a piece of rod down to be a tight push fit into the bore of the bearing and drilled a tapping size hole down the centre. I then cut a slit in the end just longer than the bearings width with a hacksaw and squashed the slit closed at the end using a vise, after which I threaded the hole keeping the slit closed with the vise.

Using a bolt and putting my just made extractor into the bearing bore and tightening the bolt, thus expanding the slit rod end to tightly grip the bearing, using a hooked slide hammer to remove it. A little heat on the outside helps as well.

Commander_Keen
10th Apr 2021, 10:58 AM
The trick with pilot bearings on vehicle clutches is to get a tightly fitting dowel and packing the hole with grease. Hammer it in and repack grease as necessary to hydraulically drive out the bearing.
You can play with grease viscositites to account for different tolerances. I've even heard of guys tearing up bits of bread to achieve the same outcome.

Sparksy
10th Apr 2021, 11:20 AM
The trick with pilot bearings on vehicle clutches is to get a tightly fitting dowel and packing the hole with grease. Hammer it in and repack grease as necessary to hydraulically drive out the bearing.
You can play with grease viscositites to account for different tolerances. I've even heard of guys tearing up bits of bread to achieve the same outcome.

Or wet paper towel.

nadroj
10th Apr 2021, 12:07 PM
In a hurry once, I removed a ball race from a dead-end hole in a light alloy case, by welding a threaded rod to the inner race.
Then I could pull it out, and no harm done (except to the bearing).

I now have a really cheap Asian blind bearing puller set with slide hammer included. It works sometimes.

SurfinNev
10th Apr 2021, 06:47 PM
I have a proper blind hole bearing puller set, but before that have even used a dynabolt.

.RC.
10th Apr 2021, 07:02 PM
I have used swear words.










didn't work.

eskimo
10th Apr 2021, 07:45 PM
I have used swear words.



didn't work.

Nor me.
It lessened the stress tho

Michael G
10th Apr 2021, 08:48 PM
I did once use the 'weld inside the race' method and it worked surprisingly well.

Michael

OxxAndBert
10th Apr 2021, 11:56 PM
Hi Guys,

How to remove a ball race from a blind bore came up on another forum recently which reminded me of a method that I used to remove one.

I turned a piece of rod down to be a tight push fit into the bore of the bearing and drilled a tapping size hole down the centre. I then cut a slit in the end just longer than the bearings width with a hacksaw and squashed the slit closed at the end using a vise, after which I threaded the hole keeping the slit closed with the vise.

Using a bolt and putting my just made extractor into the bearing bore and tightening the bolt, thus expanding the slit rod end to tightly grip the bearing, using a hooked slide hammer to remove it. A little heat on the outside helps as well.

Hi John. I must be misunderstanding what you mean, as can't get my head around how that could work.

If you squeeze the slit end while threading won't you take more material out of the split section with the tap - resulting in a clearance to the bolt thread when it relaxes back to parallel? How would the bolt expand it?

The only way I can see it being able to expand and grip the bearing bore is if there was LESS material taken out of the split section by the tap, which would either require expanding the split end while tapping, or using a tapered tap and not cutting a full depth thread into the split section.

Steve

BaronJ
11th Apr 2021, 07:29 PM
Hi Steve,

The screw down the middle pushes the taper apart causing the plug to grip the bearing bore.

Argh I've just re-read what I wrote, yes you are right, I've got the work order wrong.
Thread the bore and then squash it.

I'm going to blame it on brain way ahead of my fingers, or something like that.

Thanks for pointing it out !