rod QD back brake and spindles

[tombeau]

Hello there.
I don't suppose anyone could sort me out with some photos/drawings and dimensions of the bits on a swing arm A10 rod brake QD set up?
In particular the measurements of the spindles and spacers?
Mine is a mish mash of bits '48 A7 drum /sprocket unknown brake plate and concocted spindles...and doesnt seem to work that well.
The brake plate seems to be able to wobble a bit. If the bike has been sitting on the side stand, fiirst few times you use it, it howls.Presumably after this it centralises itself. I've just had it apart. There is a groove worn in the shoes, looks like its been caused by pressing against the outside edge of the drum.
Cheers,
iain

[scotty]

Hi Iain

I have a 55 GF with QD and rod rear brake all going together slowly in the shed.

Here's what I have..

Spindle dimensions:
Overall length 8 and 3/4 "
Threaded end is 9/16" dia and 1 1/16" long
Main shaft of spindle is 0.68" dia and 6" long
Spindle head is 1" dia 1 11/16"

Spacer (right side) dimensions:
Overall length is 1 9/16"
Outside dia 0.9"

Hope this helps

Scotty

[tombeau]

Scotty.
Thats superb! thanks very much for your help. I'll measure mine up and compare.
You couldn't give me the dimensions of the stub spindle in the brake drum that the wheel spindle screws into as well could you?
There's no tearing hurry for it but your help is greatly appreciated.


Isn't this great? The ability to ask for information, and compare bits within hours.

I remember years ago returning to my bike to find an old boy in a suit lying underneath it!
he was rebuilding an A10 and missing all the footrest gubbins, he needed to see what the bits he was missing looked like.
Cheers,
Iain

[scotty]

Iain

Here's the bumf on my brng sleeve that the spindle screws in to.

Length overall approx 3 3/8 "
Threaded portion is 9/16 dia and 1 1/4 in length
Main shaft is 0.87" dia and 1 1/2 " in length (it has a couple of flats machined close to where the threaded bit starts)
The head is 5/8" long with a step up to 1.125 dia then down to 0.96" dia then back up to 1.125" dia

I've checked all my bits against parts book for A group swing arm (1954/5) and all seems to be complete and correct as far as components I have (which is more than can be said about the rest of the bike!)

Good luck

cherrs Scotty

 

[tombeau]

Scotty you are an absolute star!
Thanks again.
Iain

[tombeau]

Sorry Scotty. Me again...

I've been out measuring stuff, my stub spindle is a fair bit shorter, and the flats only just reach into the slots in the swinging arm. How deep were the flats on yours?


What I did notice though was that there is a collar that sits on top of the bearing which is the first thing you see when you take of the brake plate. It is stepped and appears to fit flush with the edge of the bearing housing...upon removal I found that the bearing is not fitted all the way into the bearing housing. If it was the collar would not be flush, which presumably it should be.
I'm hoping that this is what my problem is.

Can I be a total pain and ask for a few more measurements?

1.How thick is the collar that fits between the bearing and brake plate?

2. How thick is the brake drum/sprocket unit?

Sorry to ask all these questions, I'm worried about throwing good money after bad. The brakedrum/sprocket unit I have cost more than £50 in postage alone to get here. So I really want to avoid having to shell out for another one.

As I said no tearing hurry I've plenty of other stuff to be getting on with.
I really do appreciate you taking the time to do this.
Cheers,
Iain

[scotty]

Iain

No probs getting this info to you...its all laid out on the bench and has been begging me do dive in there for some time now !

The flats on my brng sleeve are 11/32 " deep

The collar that sits on the brng I have is 1/2" thick with the larger dia being 1.75" and the stepped down dia being 1.10".

The thickness/width of my drum/sprocket is 1.4"

Cheers

Scotty

[tombeau]

Scotty,
You are a gent.
Thanks again,
iain

[tombeau]

Well, I decided to order up all the correct spindle bits as there is a mish mash of components in there.
I now have a spindle to tight to fit through the wheel and a dummy spindle that will need some bearing fit, need to investigate the spacers some more too. Maybe I should have stuck with my mishmash.
Scotty I may to post a drawing of my hub so you can compare it to yours if thats ok?
Cheers,
Iain

[scotty]

Iain

Hope the rear hub build progresses well

Post your dwg and I'll gladly compare it to mine which still languishes on the bench awaiting quality time.

Cheers

Scotty

[tombeau]

Hi Scotty,
Thanks for all your help, I couldnt have got this far without it.
I've worked out the problem (i hope)
The brake drum I have is an early A7 plunger or rigid, it uses a much larger bearing, presumably as it is subject to greater loads.The extra thickness of this bearing effectively shortens the reach of the stub axle. Whilst I could probably get a mate to make up new bits and spacers in exchange for a decent bottle of malt, if it still doesn't work, I wont know if its my calculations that went awry, or the theory that was wrong. I'm going to bite the bullet and buy a new drum.
Cheers,
Iain