Pinion Gear Step Machining

Rowdy

Rowdy

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Last week a friend brought over a repop 3.54 ring and pinion gear set he bought about 8 years ago. Seems his is one of the sets from that run that the front bearing area on the pinion gear was not machined for a slip fit so setting the preload will be near impossible to set. Who have most people sent these to have them properly machined? Any help or contact info would be GREAT. He has had them long enough that the parts house will not take them back or offer any help. Rod
 
Rowdy said:
Last week a friend brought over a repop 3.54 ring and pinion gear set he bought about 8 years ago. Seems his is one of the sets from that run that the front bearing area on the pinion gear was not machined for a slip fit so setting the preload will be near impossible to set. Who have most people sent these to have them properly machined? Any help or contact info would be GREAT. He has had them long enough that the parts house will not take them back or offer any help. Rod
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I think any machine shop could reduce the diameter by mounting the gear on a lathe between conical centers, rotate it and use a strip of emery cloth to address the area requiring reduction. Tom Endy gave me this tip a couple months back about reducing the diameter with emery cloth. Good Day.

ps: I have a precision hone in my shop and have in the past, enlarged the front bearing. It seems to make more sense to decrease the diameter of the gear by Endy's method.
 
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I had thought about that but was not sure it would stay concentric. I know this flaw was discussed on the old Fordbarn and thought at that time the manufacturers contact info was given and they were fixing this problem on an as found and sent back basis. Rod
 
Three or Four years ago, the Early V8 guru, Dan Krehbiel (sp?) had someone that he sent the gears to, exactly for this work. You might try to contact him, and see if the info is still current. However, I would speculate that Tom Endy would have info, too.
If all else fails, you could PM me, as I have had this done locally, and might be able to put you in touch with the source. Can't you find a shop that is local for you? There should be a crank grinder, somewhere close to you??
JMO
 
Knowing the needed dimension is helpful. Anybody know what that is? Then one can determine their ability to make the correction, lathe or otherwise.
 
I have not contacted my normal machinist. Last I knew he had about a 2 month back log. Best in the area but the wait can be a real project killer for a car the owner wants back on the road in a week or less. When the place I used to work at was still open I would take the part to work with me in my lunch box and take it to our tool and die guys and they would grind it to spec or whatever small job needed done in their spare time. Usually bought them many beers after work and it was an even trade. I miss having that at my disposal as long as I did not ask much very often it worked out well. Rod
 
I may have that spec in one of my books. I know it is a hardened area so it has to be ground rather than turned by normal lathe tooling. I had mine done at work when I bought that set. We had a spindle grinder for small parts like this. Took longer to set it up than it took to grind it to spec. Rod
 
A tool can be made from a discarded axle shaft or drive shaft. Cut off the tapered end of the shaft and remove the key. The other end can be turned down to fit a 1\2" drill press. Slide the pinion on to the tapered end and install a nut finger tight. The area of the front bearing can be turned down on a lathe using a cutting tool or Emory paper, or in a drill press using a file or Emory paper. The surface is not that hard. The dimension is only .0015 smaller than the area of the rear bearing.

For a description of the process go to the web site of the Santa Anita A's of Arcadia, California at www.santaanitaas.org. On the home page put your cursor on "Technical Reference", my name will appear below, click on it.

A menu of articles will come up. Scroll to "Steering", and then to "R&P sets, Reproduction Blues". The article is a pdf file, you are welcome to download and print it out.

Tom Endy
 

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Thanks guys as of sometime this morning before I got up it is taken care of. Another local machine shop ground it for him and he started re-assembly. Hope he has it together by Thursday morning so I can help him put the rearend back in his pickup. At any rate I think he will enjoy the difference in speed compared to his original 4.11's that finally failed. Rod
 
I agree with Jim, if it is probably a few tenths I would just polish it off. The emery cloth will just follow the surface and remove material evenly. This would be in a lathe or some other device to rotate the part. I would start with 180 and finish with 320 or finer. It sounds like some want to over engineer a simple operation. If you are measuring a couple a thou over then grinding would be the best. I would grind it with my toolpost grinder if it needed that much.
 
Like mentioned in my last post it was ground this morning and re-assembly is started after getting a good used axle from me about 2 hours ago. Now that he is upgrading from 4.11's to 3.54's the next thing he will likely want a high compression head and a cam change or possibly a brake rebuild. Rod
 
NEW Volvo camshaft with rear journal .010" too large. Machinest took it to the back room, back in 7 MINUTES, PERFECT FIT!
Bill W.
 
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