Fabric Couplings: The Good and the bad

[GK5268]

Just to conclude matters, the cherished supplier has this morning contacted me to say that he has contacted his manufacturer to resolve the sizing issue and that these have now been withdrawn from sale until correctly sized ones are produced! He has also offered to refund my machining costs against my next order, so that is a satisfactory conclusion!

[Ivor Hawkins]

Gary, you are not related to Ralph Nader by any chance?!

[GK5268]

No!

I don't know how long these bolts have been supplied by others - it could be for a number of years - and so might be the cause of these now so-common fabric-joint failures, which is why I wanted to draw attention! Probably nothing wrong at all with the joint itself just the fixings!

When my car is returned to the road, it will get used (as I am using the Ruby), so it will get a good real-life testing!

[Zetomagneto]

Can’t see how these bolts would cause failure of the fabric joint.
At worst they will just move the propshaft back a 1/4” or so.
Our cherished suppliers do an excellent job, the parts are cheap, and I for one 
don’t mind do a bit of fettling if needs be. I wouldn’t complain about a minor issue on a forum.

[Robert Foreman]

Zeto, 
  the radius in the corner was too big allowing it not to sit flat on the coupling. 
Also I can see that the split pin hole would not work unless lots of washers were used.

[JonE]

Our cherished suppliers do an excellent job, the parts are cheap, and I for one 
don’t mind do a bit of fettling if needs be. I wouldn’t complain about a minor issue on a forum.

It's a difficult one, as there are lots of newbies coming in (we all hope) who perhaps don't have your engineering understanding and skills, Zeto. Suppliers are no doubt busy and one little part - it might be good that it is raised if it doesn't get picked up through the normal "this doesn't seem quite right" channel - which didn't happen to work this time.
Otherwise lots of new people start using potentially slightly wrong things - whilst the old hands quietly sort things out?

It has got to be a (tiny) barrier worth minimising for encouraging people to stay with a Seven for the longer term (i.e. rather than buying something, getting annoyed with faffing around trying to fix things perhaps without adequate support, and then selling up at a loss to return to a classic)

So we should look at it as positive - asking questions about slightly different shaped parts on here, so we can all learn to fettle if we DO need to, or specs can be updated. I was thinking this with brake lever cotter pins last week. New ones from somewhere - can't remember and it doesn't really matter anyway - didn't fit like another older one I had which fitted straight in. I will try to remember to check size when I buy some more next time!

[Russlin]

Hi Winston, Have just rebuilt a 1928 Austin 7 (magneto engine) found unused for many years. When I saw the delaminated fabric coupling I was reminded of my father struggling to make a vibration free coupling for our 1927 Oldsmobile. As I did not want to repeat history with the Austin I fitted one of David's Hardy-Spicer propshafts as a replacement. It provides smooth and reliable service.
I believe that oil contamination may be the cause of fabric coupling failure on some cars.
Russell.