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I have recently removed both rear shock absorbers for cleaning and refurbishing, using Woodrow for advice. On the spring shackle end the lock nuts and spring washer assembly on dismantling from inside out was 1, lock nut, 2, spring washer, 3 lock nut. However Woodrow shows assembly as 1, spring washer, 2, lock nut, 3, lock nut. My personal opinion is that the Woodrow method would be best as otherwise the nuts are not locking against each other. I would be grateful for other opinions please.
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Spring shackle???  = Spring pin. I do not have W book.
Starting at the spring pin shoulder.......fibre washer which is trapped between pin shoulder and link rubber bush (or in later years the rubber link bush came in 2 parts each side having a rubber built in washer instead of having to have the fibre washers....like top hat section); rubber link bush; fibre washer; key washer (key sits in the groove in the spring pin); spring washer; nut; lock-nut.
The key washer allows the nut/spring washer to be done up to the correct amount key washer just touching fibre washer(as specified somewhere I can't remember where) so that the link can rotate whilst the key washer/spring washer/nuts remain static. Without the key washer the spring washer would chew up the fibre washer (/rubber bush shoulder). It can be said that lightly tightened then the spring washer will tend to keep a slight tension between key washer and fibre washer so will take up a certain amount of side thrust wear? Once first nut done up against spring and key washer then lock nut can be put on to lock first nut in place.
Lock nuts ....it is not just the friction of the nut faces.......a fascinating subject on its own - - - 1 thick one thin ----which one goes on first --- both same size--etc...---if you are mathematical minded there are articles showing the locking action through the threads and the reaction forces vectors.
One article I like is
https://engineerdog.com/2015/01/11/10-tr...fasteners/
I will be using nyloc nuts instead of the 2 locknuts and split lockwasher.
Reminder to all - do not just copy what you found, a previous owner may have been a bodger and done it all wrong.
Dennis
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(07-01-2019, 04:08 PM)Dennis Nicholas Wrote: Spring shackle??? = Spring pin. I do not have W book.
Starting at the spring pin shoulder.......fibre washer which is trapped between pin shoulder and link rubber bush (or in later years the rubber link bush came in 2 parts each side having a rubber built in washer instead of having to have the fibre washers....like top hat section); rubber link bush; fibre washer; key washer (key sits in the groove in the spring pin); spring washer; nut; lock-nut.
The key washer allows the nut/spring washer to be done up to the correct amount key washer just touching fibre washer(as specified somewhere I can't remember where) so that the link can rotate whilst the key washer/spring washer/nuts remain static. Without the key washer the spring washer would chew up the fibre washer (/rubber bush shoulder). It can be said that lightly tightened then the spring washer will tend to keep a slight tension between key washer and fibre washer so will take up a certain amount of side thrust wear? Once first nut done up against spring and key washer then lock nut can be put on to lock first nut in place.
Lock nuts ....it is not just the friction of the nut faces.......a fascinating subject on its own - - - 1 thick one thin ----which one goes on first --- both same size--etc...---if you are mathematical minded there are articles showing the locking action through the threads and the reaction forces vectors.
One article I like is
https://engineerdog.com/2015/01/11/10-tr...fasteners/
I will be using nyloc nuts instead of the 2 locknuts and split lockwasher.
Reminder to all - do not just copy what you found, a previous owner may have been a bodger and done it all wrong.
Dennis Fantastic Dennis, thank you. Just the answer that I was hoping for. Makes perfect sense and to my small engineering brain, perfect logic.
Regards
Peter
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Car type: 1928 tourer (mag type), short chassis Gould Ulster
(07-01-2019, 12:30 PM)Biddlecombe Wrote: I have recently removed both rear shock absorbers for cleaning and refurbishing, using Woodrow for advice. On the spring shackle end the lock nuts and spring washer assembly on dismantling from inside out was 1, lock nut, 2, spring washer, 3 lock nut. However Woodrow shows assembly as 1, spring washer, 2, lock nut, 3, lock nut. My personal opinion is that the Woodrow method would be best as otherwise the nuts are not locking against each other. I would be grateful for other opinions please.
Since the purpose of any spring washer with the lock nuts is to prevent them moving against each other it is arguable that it is not needed, but if used it should be between the nuts.
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Now I am completely confused !!??
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Thank you Dennis for making engineringdog acessible. I seem to recall many years, or perhaps decades ago, ongoing discussion in the Model Engineer about locknuts. Should they be different, should the thin one be inside or outside, I am far from sure that any definite agreement has ever been reached. One thing rejected by all would be putting washers, paricularly spring washers, between the nuts. I also take the same aproach to nyloc nuts. If I was building hundreds of cars then I'd want to save ha'pennies. With just one, the number and cost of discarded nylocs is minimal.
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Spring washers are at best barely effective as a locking device.
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(07-01-2019, 09:33 PM)Chris KC Wrote: Spring washers are at best barely effective as a locking device.
All the original 'flat' spring washers I have are springless and the later square section with the sharp ends are usually too brutal for an old Austin 7.
I don't use a spring washer with locknuts at all (put the full nut on first and lock with the half nut).
The tanged washer is necessary against the fibre washer on the dampers.
Cheers, Tony P.
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(07-01-2019, 09:33 PM)Chris KC Wrote: Spring washers are at best barely effective as a locking device.
Apparently now locknuts are called jam nuts (I will still call them locknuts).
From Google, the placing of the half nut below the full nut only applies when two nuts are used on a bolted assembly clamping two pieces together.
With the Austin Seven application of locknuts to the shock absorber pins, the half nut should be placed on the outside of the full nut and tightened together without actually clamping anything, just stoping them unscrewing.
As a side issue Nylock nuts should be replaced each time they are unscrewed, whereas locknuts can be re used- less waste ! 
Cheers, Tony P.
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