I'm struggling with the search engine...... I'm looking for a source of self adhesive abrasive tape to stick inside the brake drums to bed in new brake linings. I know I've read about it on this site sometime ago, but cannot find it. Also what grit is best, maybe 120G ?
Thanks,
Bob.

I doubt if sticking tape inside the drum would work. Even if it could be persuaded to stick the thickness of the tape would ensure that the alignment was wrong.
I simply fit the shoes and drive the car a bit. Then take the drums off and remove high spots on the lining with a file.
New linings are not usually very far out so no packing of the cams should be needed.

Location: Melrose, Scottish Borders

I agree with Jim, I think the best way to bed in new linings is to go for a drive and apply the brakes gently and assuming they are adjusted correctly and the drums are true it shouldn't take too long for them to bed in and progressively become more effective to the limits of A7s. In the 1960's before the days of universal disc brakes I don't remember being advised to do anything else so why start now?

Location: NE Peak Corner

Hi Bob. It worked for me. I have successfully used sandpaper in this way, saving many miles of bedding in on the road. I used separate sandpaper (actually aluminium oxide) and thin double sided adhesive tape. For more details see my article "Bedding in new brake shoes" on the technical pages of the Dorset A7C website.

Location: New Forest

Sevens now often do low mileage, and now seldom brake for slower traffic ahead, so bedding is a problem. Can also check with chalk on drum.

I found with Girling brakes that, for reasons uncertain, considerable fitting of the shoe ends was necessary to get reasonable contact. Ideally needed building up with weld.

Beware NOS linings with asbestos

Some time ago a there was a post about a radial arm device for contouring shoes; may be of interest. Someone may have a reference to.

Location: Auckland, NZ

Thanks John - that is the type of thing I had in mind. I have uncoupled brakes and am struggling with the fronts to get them even and not jamming on full lock. New linings, rebuilt shoes, new cams, new cast drums. I do very few road miles outside of trialling and don't want to drive around with the handbrake on forever! I need a good handbrake for stop/restarts on the trials.
I reckon if I can bed them down nice and evenly by your method then my problems will be over - well maybe!

Just reporting back in again...........I used the John Cornworth method exactly as described. Superb results! Achieved good even bedding after finding that I needed just the slightest more shimming on one shoe, which I previously thought was spot-on.
Hardest bit was cleaning the tape off the drum afterwards!
Thanks John.