Idler gear remove and replace tips?

[Tom]

Tim,

I think releasing the stress caused by the stamping is the key to salvaging these gears. However I have no idea on exactly how to do that. Maybe shot peening? Please keep us informed.

Tom

[GerryH]

I believe heating to 400 degrees and holding for 3-4 hours is the method used commercially to stress relieve a part. There are big ovens in the area here for all the oilfield manufacturing. I can check further if needed.

[Doug]

Electric motor rewind shops have burn out ovens that can heat to about 600F. The warm up and cool down cycle is about 12-18 hours but I don't think this is enough heat to aneal in one shot. I was under the impression that at less than critical temp you have to reheat and cool many times to destress cast.

But what do I know, I'm an electrican.

Doug

[GerryH]

At http://www.efunda.com/processes/heat_treat/matl_modify/stress_relieving.cfm they say----

"Stress relieving is done by subjecting the parts to a temperature of about 75 ºC (165 ºF) below the transformation temperature,line A1 on the diagram, which is about 727 ºC (1340 ºF) of steel—thus stress relieving is done at about 650 ºC (1202 ºF) for about one hour or till the whole part reaches the temperature. This removes more than 90% of the internal stresses. Alloy steels are stress relieved at higher temperatures. After removing from the furnace, the parts are air cooled in still air"

[GuyFawkes]

just posted a looong bit about this in the general discussion section

[kyradawg]

Peace&Love , Darren

[sawmiller]

Hi guy

There's more to it than just running the gears thru the oven,I used to work Eaton axle now Dana. The gears are ground( after) coming out of the oven. I could get the gears run thru the oven but how would i get them finished.


Regards
Tim

[GuyFawkes]

see the looong thread in general discussion

[Tom]

Well I tested my gear lash as described as above and at the rim of the flywheel I get about 1/4" of movement to take up the lash. This seems reasonable to me and I think I'll leave things as they are for now.