29-06-2024, 10:03 AM
(This post was last modified: 29-06-2024, 10:05 AM by John Cornforth.)
Hi
The end play should be minimal (a few thou), or the timing will vary. From memory the standard Tufnol washer is about 30 or 40 thou. I see no reason why a second washer should not be added to reduce play. The shaft diameter is something odd like 0.48 inches.
I have found a bit of variability in the position of the hole in the gear relative to the face of the boss. I don't have space for a lathe, but have a couple of friends who have such beasts and just buy them a beer or two if I need a little job done like making a custom Teflon spacer - see pic. Original steel gears are hardened, but if your old one is brass you might be able to cut it down with hand tools. Filing flat could be a challenge !
The end play should be minimal (a few thou), or the timing will vary. From memory the standard Tufnol washer is about 30 or 40 thou. I see no reason why a second washer should not be added to reduce play. The shaft diameter is something odd like 0.48 inches.
I have found a bit of variability in the position of the hole in the gear relative to the face of the boss. I don't have space for a lathe, but have a couple of friends who have such beasts and just buy them a beer or two if I need a little job done like making a custom Teflon spacer - see pic. Original steel gears are hardened, but if your old one is brass you might be able to cut it down with hand tools. Filing flat could be a challenge !