Joined: Aug 2017 Posts: 780 Threads: 26
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Location: On a hill in Wiltshire
"Lapping gears"? Yes, I believe it does. But is is a long process.
I spent a day on my spare box - probably 3 or four hours' worth of lapping if you added it up, which got it into a usable state.
I reckon another hour or two would make it from "usable" to "good".
But it restores a box for which spares are not available.
I have not had much success with the turning of the gear through 120 degrees, I suppose the worm is always worn anyway.
If you do take the gear off to turn it, do not, whatever you do, hit the threaded end to try and knock it through the gear.
Hitting it will mushroom it, and fixing that is a pain. And, having wrecked it, the gear is still fixed tightly on the shaft.
I made a puller from 1/4" bar, which eventually did the job. But had to grind the gears in, after all.
Joined: Aug 2017 Posts: 66 Threads: 17
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Many thanks to everybody for their helpful suggestions.
John
Joined: Dec 2017 Posts: 1,160 Threads: 68
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Location: Nottinghamshire. Robin Hood County
Car type: Austin Ruby Mk1 1935
Charles lapping the gears does make a difference. What you are trying to achieve by lapping is to adjust the central portion to take out the play then wear down the section at the end of each lock that is less worn (because of less use on full lock) so that it’s full travel is all warn the same and there is less or no play anywhere along its length.
John Mason.
Would you believe it "Her who must be obeyed" refers to my Ruby as the toy.
Joined: Aug 2017 Posts: 2,748 Threads: 31
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Location: Auckland, NZ
03-08-2020, 08:23 PM
(This post was last modified: 03-08-2020, 11:28 PM by Bob Culver.)
Some consider very little or no backlash undesirable in which case lapping may not be worth the effort. The box on my car has done about 130,000 miles and with the gear turned but no lapping lost motion is about 1/4 inch.
A possible problem with lapping, if done in one position as soon as the mesh is altered a tiny degree rides on the unlapped. With car cwp the lapping machines oscillate the gears around a base postion slightly.
valve grinding paste is not very aggressive and breaks down. Carborundum powder needs very careful clean up and must not get into bushes.
Joined: Aug 2017 Posts: 66 Threads: 17
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As it happened, the draglink endcap came off without the need for compression as there was zero spring pressure on the cups.
Once straightened, I might follow Charles' example with the adjustable endcaps. I'm reluctant to get any of my sash cramps greasy.
Thanks again
John
Joined: Mar 2015 Posts: 5,436 Threads: 231
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Location: Scotchland
It is wise man who keeps woodworking and metalworking tools separate.
Joined: May 2018 Posts: 2,096 Threads: 110
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Location: Llandrindod Wells
Car type: 29 Special, 30 RK, 28 C Cab
Hi All
Wood and metal hmmmm.
I have separate sheds (of course I’m not showing off ?).
Although cross contamination is frequent. I’ve currently given up on trying to use my wood lathe with an 8” swing to lightly skim brake drums. My metal lathe (substantially socially distant) has a meagre 3” even in the gap!
Cheers
Howard
PS I have some sash cramps but like Charles invested in Tony’s Drag link ends modified with adjuster AND grease nipple!