G series Axle, I think I got a Friday afternoon one

[TheStitt]

Hi all I'm in the middle of doing a disc brake swap on my RN2X diff, and I found this interesting point







its like the splines are offset at the end of the axle.

The other axle is dead straigh ruler sits flush anlong the axle the whole way around.

However the other axle seems to be offset, like its over one way.

Now im wondering can I get this straightened or should I just get another axle shortened to suit??

Any ideas inputs.

Thanks Stitt

[oldcorollas]

weird

is the rough part of that axle thicker than the straight one?
if it is thinner, then maybe better to get another one?

all it would really affect is the balance, but axles don't spin that fast, so maybe not much vibration will occur? as logn as it is not weaker (by being thinner) or wobbles around too much....

well spotted

[TheStitt]

Axles is the same diametre

the black section is 32.5mm whole way down so is the other axle,

the clear area is 31mm on both weird

[brett_celicacoupe]

i wouldnt worry about it too much.

the casting mould was probably getting toward the end of its life. since the bearing section axis and the spline section axis are the same from the machining process, it will be all true relative to each other.

most brake rotors are out of round a little (.5mm?) as the casted outer edge isnt machined.

regarding vibration; very negligible. moment of interia would be small and rpm of the axle is also very low

[The Real Roadrunner]

its like the splines are offset at the end of the axle.

The other axle is dead straigh ruler sits flush anlong the axle the whole way around.

However the other axle seems to be offset, like its over one way.

Now im wondering can I get this straightened or should I just get another axle shortened to suit??

Thanks Stitt

its quite normal, not ideal but still normal.

id run it unless you plan on making 5 million HP, but then id go 9" or bigger

cheers
linden

PS how is the bus going? ready to rock yet?

[PeteH]

Yeah as per the above posts that axle is perfectly normal. The process of making an axle is fairly rugged and as it isn't a visual item not much care is given apart from making sure it "fits in the axle tube"...........honest that is a response I recieved once.

First up the axle is forged from a billet, so heated and belted with a lot of force. Following on from this the axle is allowed to cool to ambient temp during which they can bend due to differing rates of cooling along opposing sides of the shaft length. This can happen due to the way axles are arranged and stacked after forging, i.e. bottom shafts cool slower as hot shafts are loaded on top, and top shafts cool quicker due to less heat mass above.

Now that the axle forging has cooled, and probably warped, it goes through another heating and cooling process. This process, annealing, is the one most likely to promote warping as the axles are jumbled on top of one another and loaded into the furnace for a few hours at a temp I can no longer remember.....thankfully. Next step remove axles from furnace, stack into baskets and cool to ambient.

As per every automotive component manufactured there is a specification controlling the amount of bend a shaft can have. Prior to machining, which is after the above ops, each shaft will be measured for run-out. Any shafts found to be outside these specs will then go onto a straightening device to try and bring the shaft back to spec. The result of this is a bunch of shafts with varying degrees of straightness, and as per your images shafts with varying machined surface to forged surface runout. Some look prettier than others but thay all get the job done.

Don't be too concerned about it not looking pretty

[TheStitt]

no worries I wasn't aware of the process, and was a little worried about stressing bearings with what I thought was a dogey run out.

Thanks all for the input Pete thats on of the best answers i've seen for a while.

Linden the Bus is back on the agenda, the problem is coin still, still on probation with new job so don't have real play money atm. I've been flat out to but i'm back on it and I hope it happens soon

[allencr]

It's a pretty good forging but on that rough end there isn't a really good way to to find its center for the center drill. Those tapered holes are the basis for all machining and getting it drilled in the right spot has quite a bit of leeway.

Make some dead centers out of nails & wood so you can spin it, vertical might be easier then horizontal and when it's spun, I think you'll see that the machined surfaces don't have any runout & it's not bent.