Porsche 356 B brake drums

bugat5speed · Post by **bugat5speed** » Sun Oct 08, 2006 10:08 am

Hi together,

are there any new brake drums achievable in the market? If so, please give me a link, or any other info is appreciated.

Thanks

Martin

davidppp · Post by **davidppp** » Sun Oct 08, 2006 11:14 am

Hello Martin.

I have one NOS rear, for a B.

Kind regards
David

bugat5speed · Post by **bugat5speed** » Fri Oct 13, 2006 2:25 pm

Hi David,

try to get at least 2, or to find another one who has one. Will come back to you on this matter. Thanks for this help.

Martin

Mick · Post by **Mick** » Fri Oct 13, 2006 4:46 pm

Two on e-bay

Nigel Cousins · Post by **Nigel Cousins** » Sun Oct 15, 2006 6:16 pm

hi Martin
can you not machine yours,I would be happy to help, have just machined mine and they came out just fine.
Nige

davidppp · Post by **davidppp** » Sun Oct 15, 2006 6:19 pm

Hello, Nige.

Skimming tends to be a very short=lived respite from the awful judders!#

The problem is these old drums corrode between the steel and the ali..it is acontinous process..and distorts the liner..

Kind regards
david

Nigel Cousins · Post by **Nigel Cousins** » Sun Oct 15, 2006 6:41 pm

Hi David

The continuous reaction between the steel and the ali is a problem. I skimmed my drums two weeks ago and will see how long it lasts. These drums at a reasonal price are getting harder to find, so I am also experimenting with new steel incerts made from T4 rear drums.

Best regards Nige

40 scout · Post by **40 scout** » Sun Oct 15, 2006 7:22 pm

Nigel and David - I'm watching this thread with interest - I've just removed the rear drums from mine - Its been standing (unsiezed) for 27 years!

Anyway remove the drums - turn them over - looks like the thin steel ring that sits inside the raingroove? on the outer lip of the drum has caused some of the ali lip to crack.

Looks like the pressure / reaction of the steel ring has caused the cracking of the lip.

It looks like the crack can be easily clamped shut and maybe welded back into position. The actual inside of the drum and the area where the shoes bite looks fine although very dirty.

Before any one starts shouting u cant weld up brake drums!!!! I'm talking about the cracked lip section only. Will try to post a pic of the damage tomorrow.

David - why should a drum go out of alignment / true once skimmed? I'm sure you've heard of this before but why??

I'd prefer to restore and keep my drums if poss -

Nigel - who did you use for skimming?? Any ideas on cost??

Trying to weigh up my options before diving in

All the best

Steve

Nigel Cousins · Post by **Nigel Cousins** » Sun Oct 15, 2006 8:19 pm

Hi Steve

Hope this will answer both of your questions. The steel ring goes out of true because the galvanic corrosion between the two materials causes the ali to oxidate and grow which pushes the steel liner out of true. It is common for the steel wire band to cause the rim to part in the same way

I have not heared of anybody welding the back it is normal to remove the wire and turn off the damaged material the inner lip of the back plate will stop water ingress and our cars don't go out much in the rain these days.
The wire is there to stop the drum ringing not realy a problem.

As far as machining I turned the drums myself, I have access to a lathe and mounting jigs to turn front and back drums. Drums should be machined as pairs according to the Porsche specs to stop pull. I'm based near Bournemouth and happy to help you out if your drums need a skim.

Best regards Nige

40 scout · Post by **40 scout** » Sun Oct 15, 2006 11:40 pm

Thanks Nigel - I'm enlightened!!

Turning off that cracked ring seem like a very good idea to me - I was trying to work out what the steel inner ring was for!!

I'm in Portsmouth although make trips down to Bournemouth where my car is in the body shop at the moment.

If you are able to turn the lip of my drums down and run them in the lathe to check for true/skim I would be very pleased.

At the moment I've got the rears off the car - they are dirty (could do with vapour blasting?? tho can't find anywhere in Pompey) I'd be happy to drop them off to you after cleaning them if you are able to help.

Many thanks

Steve

Rustbucket · Post by **Rustbucket** » Mon Oct 16, 2006 9:38 am

I am working on mine at the moment too....
I have just stripped down on front, and used a wire brush in a drill. A cheapo thin wheel type is what you need- they can get in the fins if you have them! looks cool now...
I am hoping my drums are ok too. Having had them on and off the car a few times now I am hoping any catching noises is just from them not being tightened up properly.
Has anyone looked into the marine industry to see if there is something to stop the corrosion problem? didnt landrover have the same problem with their early chassis and bodywork ?

davidppp · Post by **davidppp** » Mon Oct 16, 2006 4:52 pm

Hello rustbucket.

I have given this a bit of thought in the past.

The corrosion is essentially electrogalvanic.

And will be slowed down if not stopped by eliminatiing the electrolyte solution betwqeen the dissimial metals.

The first thought would be to heat for long period to drive out the water vapour, then use something like the Green Locktite which has good capillarity and is used for sealing cracks on racing cars..

But I suspect we are not going to solve this..the like of a bimetal drum is prertty harsh and demanding..and many have tried over the years to make an acceptable aftermarket drum at an advantageous price..and all have been fialures, and most very dangerous..

Kind regards
david

40 scout · Post by **40 scout** » Mon Oct 16, 2006 10:17 pm

I see Tanner are listing new drums in their new catalogue (arrived today) - no price tho

Steve

DDK - Die Deutschen Klassiker

Porsche 356 B brake drums

Porsche 356 B brake drums

356 brake drums