External contracting vs. internal drum brakes?

[MikeC5]

It seems like more than once I've read here that once people start to dig into a restoration on an early DB (14 - 26), they find the brake rods switched so the foot (service) brake is connected to the internal shoes and parking brake to the externals. Could it be that the internal configuration works better? The linings on my 25 are no newer than 1947 and despite a few attempts to get the externals properly adjusted, the internals do a much better job of grabbing the drum and slowing the car down. I wouldn't think the parking brake lever affords significantly more leverage than the service brake... Visual inspection does not show any rivets even with or above the brake lining surface. Of course this may be due to simply the condition of the linings (they all appear to be intact), so I may be jumping to conclusions here. Opinions?

[Ron Lawson]

Hi Mike As well as my Senior6 that is being restored we also have a 1927 Chevrolet Capitol model She only has 2 wheel brakes like your 25 The problem is that when it rains and water sprays onto the brakes the external band is absolutely useless so I supose that they have been changed as the internal shoes stay drier therefor giving you better brakes in the wet The Chev is still original and she can be a bit of a handfull Its not the first time I have had to make a grab for the hand brake to assist in slowering her up Hope this explanation helps Cheers Ron

[MikeC5]

Thanks Ron. That makes sense although mine do very little even when dry. I'm going to put new linings on and try to get them adjusted properly and see if that doesn't improve things.

[Layden B]

Internal expanding brakes also have a much higher degree of self actuation than external contracting.

[R.White]

Hi Mike. The leverage of the hand brake is, I believe, considerably greater than the foot brake. I also run another car with cable brakes and today I went to have it tested. The Austin 7 has notoriously bad brakes (although they operate on all 4 wheels, the drums are only 7") and half shafts can snap if put on a roller type brake tester so they are usually tested with a decelerometer- or "Tapley" meter.

Originally, these cars had the foot brake operating on the rear brakes and the hand brake on the fronts but later they were coupled so that on my Austin, the foot and hand brake lever did all four wheels. Unfortunately, there was no compensator fitted which makes for tricky adjustment - especially as you have to allow for slight front axle rotation due to flimsy radius arms and also the left rear needs a slight lead over the right due to a slight torsional twist of a cross shaft and flexing of it's brackets. Oh the joys of Austin Seven ownership!!

This time the tester just asked me if they worked O.K.because he really couldn't be bothered to take the car for a test drive with the meter. I said they did and to prove the point I drove along the forecourt and did an emergency stop with the handbrake and foot brake hard on together. I left rubber on the concrete, and the inspector was more than a little impressed !

Anyway, back to your point about Dodge Bros.rear brakes. Layden B is correct, I believe in saying that internal expanding brakes have more 'self actuation'. I think this is important, but Ron makes what I believe is a salient point regarding the inadequacy of externally contracting brakes in wet weather - although yours should work properly in the dry so best of luck with fitting new linings. I have heared other people say they have got into a bit of difficulty with relining shoes but I have managed it myself - although you really need the proper 'anvil' type tool to get a satisfactory job with the copper rivets. Also, choose a 'soft' lining if you can for better stopping and no squealing.

Ray.

[MikeC5]

Thanks Ray. I do have a rivet set tool. I removed one of the external contracting bands and found areas where it didn't have a very uniform curve. It appears someone with llittle patience replaced them at one point. I may try swapping the rods and see if the internal drums perform better at some point.