12 replies to this topic

[pwoolley]

Dear Forum,
I have a 1959 cooper monaco fitted with alloy wheels of that period. I have noticed that the wheels fitted have cracks appearing in the spoke sections. There appears evidence of welding repairs from the past for a similar problem. Can anyone advise what the base alloy material of these wheels would have been and wether there exist proficient welders for this type of job in the UK. I have tried a specialist welder locally but we are struggling to get any bond to the parent material with various grades of aluminium rod. Who originally made these wheels and does anyone make new ones?

[Peter Morley]

Dear Forum,
I have a 1959 cooper monaco fitted with alloy wheels of that period. I have noticed that the wheels fitted have cracks appearing in the spoke sections. There appears evidence of welding repairs from the past for a similar problem. Can anyone advise what the base alloy material of these wheels would have been and wether there exist proficient welders for this type of job in the UK. I have tried a specialist welder locally but we are struggling to get any bond to the parent material with various grades of aluminium rod. Who originally made these wheels and does anyone make new ones?

The base material is possibly old magnesium VW gearbox cases melted down and recycled, given they had been used the material was contaminated with oil etc and not of the best quality even when new - that is what early Coopers used, by the time they made Monacos it might have improved but they weren't likely to have bought the best most expensive materials.

While I might consider using good condition original wheels (of which I have a few in various sizes) I wouldn't want to know about using repaired original wheels.

There are several people who make new Cooper wheels, including:

Len Selby: http://www.historicr...rts/wheels.html
Not sure if he does the bunch of bananas type though...

Crosthwaite & Gardiner: http://www.crosthwaiteandgardiner.com/

Plus people like Retro track and air, Peter Denty etc will all have sources.

Peter

[Doug Nye]

As above. Replace them! The wheels were cast originally, off the top of my head, by Stone's of Deptford (?? or Dartford???). They worked brilliantly well in period but were intended for 12-24 months' life only. The material used was markedly inferior to Connaught's choice for their contemporary cast wheels. A friend with 'Cooper' written right through him like a stick of seaside rock once told me that the wheels were made of 'Crapite'. They did improve as time went by, but Charlie Cooper would never pay ten shillings where 'alf a dollar would suffice...

DCN

Edited by Doug Nye, 26 May 2009 - 19:17.

[Derek Pitt]

Hi Woolley,

I can't help you with your wheel question, but I note you got good advice from one poster so far. This forum is an amazing place and I am sure you will receive help with nearly any question you care to ask.

I would dearly love to know the history of your car - prevous owners, racing history and in particular its motive power and cubic capacity - can you oblige please?

Regards from Antipodes
Derek

[fbarrett]

A friend with 'Cooper' written right through him like a stick of seaside rock once told me that the wheels were made of 'Crapite'.

DCN

Doug:

Is that anything like Analite, what '36 Buick pistons were made of?

Frank

[Ray Bell]

More like 'unobtainium', but with a major difference...

Perhaps 'readilyobtainium' would be close?

[Derek Pitt]

More like 'unobtainium', but with a major difference...

Perhaps 'readilyobtainium' would be close?

Steady Ray,

you are approaching being humourous...

Derek

[cooper997]

Doug,

It was certainly Stones. J Stone & Co (Charlton) Ltd, Charlton, London SE7 that did early casting work for Coopers. They told everyone so, in their adverts in the series of early 50's Cooper yearbooks. One can only assume they were still casting for Coopers when Owen Maddock's rose petal design went into production in 1956 and beyond.

Interesting that this subject has come up on TNF, just yesterday on a specialised Mini forum - www.mk1-performance-conversions.co.uk - there was discussion on the 10 inch magnesium rose petals that the CCC race Minis (and others) used.

From my own experience with the 10 & 12 inch Mini versions, 'Crapite' was still being used on these 60's versions too. Would be great if we could confirm Stones were still casting these later wheels too.


Stephen

[Allan Lupton]

A friend with 'Cooper' written right through him like a stick of seaside rock once told me that the wheels were made of 'Crapite'.

DCN

That'd be a bit like the "pistominium" that MG cast the R-type final drive casings in. (i.e. scrap light alloy of unknown provenance).

[Doug Nye]

I have mentioned this before but when Neil Corner's Auto Union V12 was in chronic overheating trouble Crosthwaite & Gardiner eventually concluded they should cast new heads for it. Neil was anxious that the new ones should be cast in the same high-tech alloy that Zwickau had used. Consequently, English Steel was asked to analyse a sample from the original head. Their report cut everybody down to size. It read something like "...this is an obsolete alloy mix for which the closest modern equivalent is XXXXXX - suitable for use in garden furniture...".

DCN

[kaydee]

Dear Forum,
I have a 1959 cooper monaco fitted with alloy wheels of that period. I have noticed that the wheels fitted have cracks appearing in the spoke sections. There appears evidence of welding repairs from the past for a similar problem. Can anyone advise what the base alloy material of these wheels would have been and wether there exist proficient welders for this type of job in the UK. I have tried a specialist welder locally but we are struggling to get any bond to the parent material with various grades of aluminium rod. Who originally made these wheels and does anyone make new ones?

I wouldn’t say that these wheels were made from “crapite”.
Stones were a very reputable foundry and made a lot of castings for the racing industry.
It is most likely that these wheels are made from magnesium and you will never weld repair them using an aluminium welding rod – all you will finish up with is a dirty mess.

To check if the wheels are in fact magnesium (and not aluminium) carefully file off and collect some very fine filings from an inauspicious place (back of the wheel) and put a flame to the filings. If it is magnesium the filings will flare up.

Assuming the wheels are magnesium, the material would typically be AZ91.
This material can easily be welded with a magnesium welding rod using an inert atmosphere (argon or helium). The best people to talk to would be someone who does welding for the aircraft industry.

However, having said all that you would need to be very, very careful about weld repairs on a cracked wheel used for racing. If the wheel is cracked and there is no sign of impact damage or casting porosity then it is most likely a fatigue initiated crack. This means the crack is in an area of high stress and the wheel is most likely to crack again in the same place. You would certainly need to continuously monitor the repaired area for further crack initiation.

However, if new wheels are available, (as stated by other posters) I would certainly be replacing the old wheels and perhaps check that the new wheels have thicker sections in the critical area.

Kaydee

[pwoolley]

Thank you all for your speedy replies and usefull information. With regards the history of the car it was reputedly driven by Chris Bristow in 1959 then went trough several hands who's names I will post later, before ending in the ownership of John Harper, who campaigned the car sucessfully for many years culminating in the BRDC championship for 50's sports cars in 2004. Once again, many thanks,
Paul Woolley

[Lee Nicolle]

I concur with other posters, if they are cracked replace them. And if they are hi mag content they are 50 years past there use by date!Do not even attempt to weld them.
Speaking to a manufacturer of well known quality mag wheels of the 60s-70s he is of the opinion [and hindsight] that the hi mag content alloy used in those days has a certain amount of porosity [ the tyres always go flat over several weeks] and the moisture content has made the alloy diseased and suitable for a shed ornament! Modern alloys is marginally heavier, a lot denser and a lot more user friendly because of the alloy type and heat treatment used. Old VW cases suffer the same problem and a lot of alloy castings were made from old VW cases.Later VW cases were made from heavier stronger materials which are far stiffer and fatigue resistant.