More questions on gear pattern

[NMBronco77]

Following up on 69Bronc's thread, I am the "father in law" he mentioned. I posted some pics on that thread but I am going to put them up here again. I have pics on patterns with shim thicknesses of .028, ,024 and .020. Some of the replies to 69Bronc's thread werer saying that the pinion was too close at the .020 shim paterns pictured, but I had done .024 and .028, and they looked real bad. Here are some photos showing in order of .020, .024 and .028 Tell me what you all think. I am curious about WHY you think it should be moved one way or another. What are the indicators that you are going by. I would like to better understand how to read gear patterns so an explanation of what you are basing your reccommendations on would be greatly appreciated..

 

[truehi9]

Try .015, show us that and the .020 again but both sides of the tooth.

By moving the pinion in, less shim, the pattern moves deeper towards where the tooth is connected to the ring. By adding shim the pattern moves more toward the tip of the tooth. The object is to put the pattern in the center depthwise not lengthwise.

I'll add more info after more pics. I'll watch this thread tonight so you don't have to wait so long for a response.

Chris

 

[NMBronco77]

Ok, Here are pics of top and bottom, (or front and back) of the .020".
The shop is shut down for the night but I will try .015" tomorrow and put on pics.

 

[truehi9]

OK. I'll try to keep an eye out for it.

 

[Devin]

Welcome to the board, "Dad" ;D ;D

These guys will hook you up. Sorry I didn't make it over there today.


You will have to post some pictures of your rig so these guys can drool.

 

[SaddleUp]

When the pinion is too close the pattern tends to go deep on the inside (drive side) and high on the outside (coast side). Having pics of both sides of the tooth are critical since it can look fine on one side and be off on the other. In the case of the pics above the drive side is showing the pattern deep in the tooth. You mentioned that the backlash was not in limits in the other thread though so I would get it in limits first since the pattern can change significantly from just 0.003 of backlash change.

 

[NMBronco77]

OK, I have removed the .020 shim and put in a .015. I have also double checked the BL and it is falling in at .007 - .010. So now I have pics of patterns of .028, .024, .020 and .015. On this post I am sending pics of .020 both sides and .015 both sides. The .024 and .028 are shown in earlier posts. Am I getting closer or further away from correct?

 

[truehi9]

It seems funny that the .015 and .020 basicly look the same. That being said I'd say your about right with a .018. You could try a .010 though and see if it gets better. My bet would be that either the gears or gear case are not quite machined correctly and that is the best you'll get. I just put a set together for a drag race guy, Currie 9+ case and Richmond gears that looked exactly the same way. If it feels smooth when you run the pattern your probably going to be fine.