Brake drums

[Dakota]

Hi
does anyone know what type of steel was used to make the liners to a 356 brake drum and what the intefearance fit should be at room temp, I think the American registry went into this in some detail butcannnot find the article . Thanks Bill Russell.

[Mike Smith]

Bill,

It is /was - Spun Cast Iron but I know nothing about the grades etc

With regard to the interferance fit- it should be possible to work this out if we cut a drum up - I probably have about 40 drums all of which need re-ning

I had a batch re-lined some years ago but I had to have 10 x drums worked on and the bill was £280-00 per drum

That is just too much money tied up in one item and for which most owners do not want to pay

Current Price for new Forged Drums is £750 each - DO NOT even think about producing cast ones - they WILL break

[rocket280]

The jan\ feb 2008 356 reg magazine has an article about a company in the uk that re-lines 356 drums. It says they use steel liners that have a 0.015 inch interference fit. They then heat the machined drum to 350 degrees f and drop in the new liner. They also use 4 pins to keep it in place. the company is called crosswaite and gardner. I think roger bray do relined drums on an exchange basis too.

[912uk]

I might also know a company nr me that does this sort of stuff. Infact two from my metal work days. kimber Fiction and a old school machine shop in the forest I only know how to drive there..

I could ask..

[Winston Teague]

If Crossthwaite and Gardener say they can do something: they can. They can (and usually have ) made anything. They are currently making a few (!) Grand Prix W125 Mercedes and have already made new V16 Auto Unions for AUDI!!!!! They have also made Ali Knock-on wheels for 356s in the past. Brake drums should be a piece of cake. Winston

[Mike Smith]

Winston,

You are absolutley correct but it is about quantity, price and return on invested capital

I have all the time in the world for Dick Crossthwaite (Gardner is no longer with us) but it has to be viable for them - and that means 10 x drums at a time and as I said in a previos message it was £280 / drum (6 years ago) - I have no idea what it might be now - Lets guess at £ 350 / drum (it wont be less)

If they are rear drums 50% of them are scrap (splines Shagged) - so there is no recovery on them on an exchange basis

Another 10% of all drums are too heavily corroded to re-sell as re-furbished - so there is no recovery on exchange there

Then, as a company, we really would like to make a profit, just occasionally, - how much do you want to pay for you refurbished drum?

So lets say each drum that we have to supply (because the exchange drum is U/S) is worth £100 in a knackered condition + £350 = £450 + 30% Profit = £585

£750 each from Porsche for a NEW Drum is starting to look quite reasonable

I have not added on the Bank interest on the invested capital - Barclays have just told me that my very small Working Overdarft will cost me 22% /annum next year

[Winston Teague]

I hadn't realised it was C&G that did them last time. Frightening though the prices are, we must accept that these are important parts and expensive good quality drums are better than cheap poor quality ones. Winston

[Mike Smith]

Winston I agree absolutely

As with most of these things, you only buy these items once and as the old adage goes

`Do it Once - Do it Right`

Or for the less enlightened

`Never time to do it Right - but always time to do it over`