Silver steel with roller bearings.

I've been asked to make some bearing bushes for inside a roller bearing race.

Is silver steel suitable?

I have no experience of this!

Thanks,

Too many unknowns to give a sensible answer.

It might be OK. My only experience is mild steel running inside a needle roller race on a car steering column. Very slow speed and very little side load. Its worked OK for 40 years but I would not consider it would be suitable for a motor.

Ian P

A few years ago I made silver steel rollers for hard- to- find ~80cc motorbike crowded roller bigend for a young friend and the bearing was still going strong after a year of hard work. The rollers were hardened, quenching in water, and tempered to a pale straw colour. I have made several successful less stressed bearing rollers in the same way since then for various vintage machinery repairs. Colin

From me2576

Home made roller bearing from 40cc petrol engine

crankpin
Made from silver-steel, this was screwed into
the web with a fine thread. Before finally
pegging into position it was hardened and
tempered to a deep straw colour and lapped to
size. Two thous. were allowed for this operation
and no appreciable distortion occurred through
the hardening process.

Rollers
A few preliminary trials showed that unless
the rollers were constrained, serious distortion
would occur through hardening. Thirty-seven
1/2 in full lengths of 1/16 in. diameter silver-steel
were cut off and pressed into a mild-steel tube of
the same length and lapped in the bore to a
diameter of 7/16 in., or more exactly, 0.4375 in.
This number was selected because it is the
nearest number of 1/16 in. diameter circles to the
required number which lie geometrically in
contact. (It provided a goodly munber of
spares.) With one at the centre, successive
layers were 6, 12, and I8. They were secured
against movement by a spot of soft solder for
facing to length on the emery wheel. The
solder was cleaned off, the rollers replaced into
the tube, and the whole brought to a dull red
heat and quenched in oil. No discernible
distortion occurred in any of the rollers. They
were polished by rolling a few at a time between
two pieces of flat brass sheet smeared with a
touch of fine lapping paste.

Outer Sleeve
Cast steel was used for this and the inside
and outside diameters were machined with
0.002 in. allowance on each for final lapping.
A mild-steel plug having a nice push it was
inserted in the bore as a safeguard against
distortion during hardening. The heat treatment
consisted of quenching in oil from a cherry-rred
heat and tempering to a dark straw, evenly heating
in hot sand.- The sleeve was then lapped to
size, internally and externally, the first dimension
being checked by a plug gauge lapped to size
also (0.545 in. diameter)

Conclusion
On assembling the parts, the results were
extremely gratifying. The 24 rollers fitted
around the crankpin to a nicety ; there was no
lateral shake in the assembled bearing and it
worked with a pleasing ease and smoothness,
each roller turning evenly.

Edited By Ady1 on 16/04/2014 10:24:28

Dependant upon the size of the needle roller bearings you can buy hardened insert bushes to fit,

I don't think the OP was actually asking how to make rollers, more the inner bush for roller beasrings, you know, like a polo but not minty

If it is a big diameter bush you may find the cost of the material a bit salty. Might want to think of alternative materials or going the case hardening route.

graham.

For light use, even a mild steel pin works ok for the crank on my Ross Yoke Stirling Engine. The bearing suppliers have a (?stainless) sleeve that is Loctited on the shaft. The silver steel should give quite good service. I think I'm off course with this, I think you have a roller bearing (not needle roller), with inner and outer races, and you wish to fit it to a reduced size of shaft, mild steel would be ok, or even 4140 unheat treated, depending on the use, an aluminium bush might be ok. Ian S C

Edited By Ian S C on 16/04/2014 13:33:03

Yes, this is right!

its for the a rear suspension on a mountain bike linkage. so needs to be hard enough to resist compression (indentation) from forces on the rear wheel.

The chap has the roller bearing race already, so a bush is needed for inside the race with a hole for the linkage bolt to go through. So polo shape as you say!

Any ideas?!

Both PGMS and unhardened silver steel have been used in the past for loco axleboxes.

Surface finish is, perhaps, more important than hardness in such a role. On mountain bike there will be serious shock loads, so Imaybe one of the manufacturer's sleeves for avoidance of doubt..

Neil

Bicycle ... So I'm thinking small bush that needs to be light and corrosion resistant. Silver Steel would work for sure but would be an unnecessarily expensive option. I concur with Jason and Ian SC above in that most common steels could be used.

I cycle (not too often ... only when I can't find the lathe chuck key) and if it were me I would try a brass, bronze or aluminium (light weight) bush first and see whether it stands up to the conditions. Alternatively, a bush made of some Acetyl or Delrin would be fitted.

Alternatively, steel, or you could get real fancy and use a stainless steel such as 304. It has enough strength, it looks nice and does not corrode easily, but is heavier.

It depends what I had lying on the rack ...

Ian