Hi Terry…re front stub axel spacer just found that Dennis Welch does them…dosnt say jag on this link but called them…they said yes they are for E type… £20 each…have just ordered a pair…Steve Front Wheel Bearing Spacer
Boy, those look AWFULLY similar to the MGB spacers.
Post some dimensions when you receive them, and I’ll compare them to an OE MGB spacer.
There may be an opportunity here, because a lot of MG owners shrug their shoulders when they encounter these parts, and toss them in the bin.
Just recieved the Dennis Welch spacers…overall length 2.375in…i believe the Mg spacers are 1.987in…Steve
The new parts have arrived from SNG.
An installation question. Does one put grease or anti-seize on the taper of stub axle where it goes into the carrier or is it put in dry?
I use a very light smear of anti-seize.
Thanks Steve…
John - per the advice I received from @Robin_O_Connor in a different thread - be sure to check the bearing fit before you install everything. Mine (axle stub and bearings ordered recently from SNG) fit fine, but Robin had issues -
Rob Y
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Good advice, thanks. Everything is from SNG so hopefully. . … .
So were mine but not good as far as the bearing fit was concerned on 2 sets.
I’ll check it tomorrow. Meanwhile here is a comparison between the original stub axle and the one from SNG. The original was only machined where it mattered. Not a problem, I just found it interesting.
The difference is that the originals were machined from forged blanks where as the SNG replacements have been machined from bar stock.
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I didn’t know that, thanks.
Hello John,
When discussing the effects of surface finish of machined components in a Mechanical Engineering class, I use a Stub Axle as an example, as there were different surface finishes present on the one part. A student asked what the purpose of the taper was (the one between the two bearing journals). I replied that it’s a very important feature of the component; it joins the small diameter to the larger diameter.
Regards,
Bill
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Hello John,
If you drag your finger nail along the surface of the bearing journals (long axis) does it have the slight feeling similar to that of a gramophone record (ultra fine thread)?
Regards,
Bill
On the old or the new stub axle?
Edit: The new one’s? Yes they do.
Is there a torque spec for securing the stub axle to the carrier? I’ve looked and can’t find one.
…scribbling furiously…
Makes sense IMO. The NC lathe was programmed to turn this part (between the smooth journals) fast and rough since surface finish wasn’t of concern. One does the same with hand turning, too.
Question for @angelw I guess there’s no surface hardening? What about hardening the entire part to make it less likely to bend, sorta like a grade 8 bolt vs grade 2? Or is it important to let it bend as opposed to snapping? That’s some ME stuff I’ve always wondered about.
Through hardening would make the part too brittle, case hardening would be ok but it’s really unnecessary the chosen material has a sufficiently high tensile strength to perform its intended duty.
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Hello Robert,
My question regarding the surface finish related to the Bearing Journals, not the taper between them. The reference to long axis was to qualify the direction to drag the finger nail.
I asked the question because even in the picture John Posted, the surfaces looked like the surface finish was reasonably coarse and is not a good thing for a bearing journal.
The surface finish produced by turning is tantamount to a very fine thread, where you have crest and root diameters. In operation, the surface contact is reduces and crests get smeared more easily with the fit becoming loose in quick time. Its the same reason that a tighter grip is achieved in an interference fit with a Shrink or Expansion assembly, as opposed to a Press assembly. In the Press assembly, the crests get smeared down to the root diameter, but in manufacture, its the Crest Diameter being measured. This what prompted me to make my own because the alternatives available were rubbish.
The original equipment are forgings, turned then the bearing journals cylindrical ground. Accordingly, the surface finish of the bearing journals is very good.
The original equipment stub axles are quite soft. Those that I’ve tested (many) were circa 28RC. 4140 bar stock is circa mid 30’s RC off the shelf. There is no advantage in making this part hard. In operation, I would rather bend a stub axle than have it break off.
Later XJS cars and I suspect other of that period, changed to larger bearing journal diameters than the E Type Stub Axle. The Taper Roller Bearing used have the same OD Cup and therefore, no change to the internal dimensions of the Hub were required. Instead, the Cone component of the bearing had a larger ID, with smaller diameter roller and more of them being used.
Its not possible to simply use XJS Stub Axles on an E Type, because the taper that locks into the Stub Axle Carrier is much larger. Its possible, but not all that practical, in terms of manufacture, to make the Stub Axle with the same small taper of the E Type and a larger inner bearing journal. However, I make a hybrid Stub Axle that uses the same inner bearing as the standard E Type inner bearing, but with the outer bearing journal to accommodate the larger ID bearing used with the XJS.
Regards,
Bill
.
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Hello Bill. I have a few questions that I hope you can answer for me.
- Do the original stub axles become unsafe with age? Should they ge changed out as a matter of course even if the journals are not worn?
- If the journals are worn, but not excessively, is it reasonable to use a bearing spacer to stop any rotation and to continue using them?
- Does it really matter if the aftermarket axles have a rough bearing surface if you are using a spacer to prevent rotation anyways?
- If one was to want to buy replacement parts from you what is the procedure to be followed.
Thanks, Geoff.