Sharpeniing Gear selector dogs

[Brett]

Is it common practice to sharpen up the drive dog gears while the bottom end is split apart?  I actually lost third gear due to a circlip shearing which i believe was due to the slightly rounded edges of the drive dogs.  This gear only had a 1mm radius on the dogs but 4th and 5th actually have more like 2mm but are better supported than third gear.  I have access to a dividing head and so should be able to grind the dogs at 120 degrees not a problem.  what i want to know is if the gears are through hardened or whether just case hardened. if case hardened by grinding i may go through the case and just end up with straight and square but soft material.  have an of you guys done this before?

[KXcam22]

Brett,
   You can grid the dogs quite easily but I would suggest buying a new gear if they are worn, unless it is big $$.  In the late 70's I used to have to grind the gears on my Huskys lots. I was hard on the tranny and the dogs would wear quite quickly (and break teeth off too).  The thing to watch out for is this: because there are 3 or 4 dogs it is a pain to grind them so they all contact (when reassembled) at the same time.  It is not hard, just takes some care and attention to get them all the same.  The hardness of the gear should be uniform throughout, not case hardened, otherwise the teeth would shear off under stress.  Hope this helps. Cam.

[Brett]

Yep they are worth s**tloads here. $160AU for third gear, let alone the selector part.  I just have to set up the little 4 inch angle grinder on milling machine and put the dividing head on and will get it exactly 120 degrees but i might even put in a little back cut so they self energise (same as a detroit locka for 4wd's)

[KXcam22]

Brett,
  A mill would be nice and precise.  Yikes! 160AU is about $300 CAD.  I always used a dremel to do mine with lots of test fitting on the shaft using a feeler guage and/or cigarette paper (thin) to get the clearances even.  Back cut of OK but makes it harder to shift under load. If you back off on the throttle (like most) it makes no diff.  Happy grinding. Cam.