Crack Tests

[Mark5000]

Hi All

I've been advised to get my car crack tested prior to testing it, after maybe 5 years off the track. It is a F5000 of 1969 vintage.

I could do without this, as I hoped to test in a couple of months... what do you think?

[fyrth]

Depends how you feel and if the car has had serious 'offs' that you know about. My Ensign F3 was laid up for 8 years before it came out for 2005 and I took a view based on the known history, whilst deciding to have the mag uprights and front stubs done as a planned job this winter. Did not expect problems and there were none, but it is another of these safety and confidence things and a failure somewhere quick could both be expensive and hurt!

A compromise might be a serious visual check, although paint and the chromate finish on mag items can hide hairline cracking that would be apparent on clean bare metal.

[simon drabble]

I would have thought it a no brainer - if an F5000 lets go at full throttle or anything approaching you will really know about it. If you miss a testing day its no the end of the world

[jamesholland]

I would strongly endorse the above posting.

Even on something as low powered as my 500 I have found items needing attention thanks to routine crack testing.

If the items concerned are bare metal you can do it yourself with one of the dye penetrant kits on the market - about £30-35 should get you what you need; Ardrox is a well known brand. If the items concerned are plated then it's doubly important to get them tested as they will be subject to hydrogen embrittlement, particuarly so if they are chromed rather than nickelled. In this case you will need to investigate magnaflux testing or x-ray inspection which is more expensive.

Some categories e.g. Supersports are subject to certificated testing every 3 years and I' rather surprised that F5000 isn't one of them.

[kickstart]

Mark 5000,
I really would urge you to get it crack tested. The car is nearly 40 years old and safety structures were not really thought about when it was made. If you can reduce the chance of a big off by checking/replacing the suspension, uprights, wheels etc then surely it is worth it.

[Mark5000]

I wonder if it is common to get these type of cracks/failures?

[zefarelly]

yes it is, and you shouldn't drive it in anger without getting it done IMO, in fact under FiA rules I believe you have to get major suspension components checked and certified or your car will be eliminated from scrutineering.

an F5000 car driven hard is a dangerous enough beast and even an experienced driver wouldn't want the concerns of a potential death trap to think about whilst trying to concentrate on keeping the thing on the black stuff.

Magnesium in particular is a material that does deteriorate structurally, SD and myself both ahd a discussion and decided we didn't want to race on unknown magnesium wheels, and thats in tin tops !

it may sound harsh, but if you don't want to die, get as much proof the cars safe before you go anywhere in it !

[PeterMorley]

Originally Posted by Mark5000

I wonder if it is common to get these type of cracks/failures?

Yes and they can also appear very quickly - a friend who prepares several TGP cars and lots of Porsches (906, 908 & 917s) told me that a recent component failure they had was on a piece that had been recently crack tested. (They now have components X-rayed which is apparently more thorough).

Crack testing should only be part of the preparation, F1 teams life all the components (aircraft style) and replace them when they have done a particular mileage.

In order to preserve the original components it makes a lot of sense to race with new wishbones etc and keep the originals for show. Of course some of these components can be very expensive, but it is cheaper than having them fail.