Rear suspension beam

[oldnut45]

Could anyone clarify if the drawing that is shown on the download section of the owners club website is for a MK1? The beam I have just taken off my car is shot and in need of replacement and looks very similar dimensionally as the one depicted in the drawing but thought it best to check.

[Stuart]

Hi Graham, welcome to the forum, I can confirm that the drawing is indeed for the MK1 and MK2 Midas, worth noting that the Midas rear track is narrower than a Mini just in case you look at Mini dural-beams as an alternative.

[oldnut45]

Thanks for that Stuart
Just reading the manufacturing notes given with the drawing and would like a further clarification. Under the section , suggested welding procedure , it mentions allowing about 6/7mm pull in and not sure what this refers to.

Graham

[ACourtney]

Hi Graham,

Welcome to the forum. Metals always shrink after welding - they expand as the heat is applied and then shrink such that they are shorter than when you started. 6 to 7mm sounds quite a lot though as the usual allowance for steel is 1mm per metre length per weld run, but that might be the difference between hot and cold. Another effect could be if the weld is only applied to one side of a beam/channel section, then it will tend to go banana shaped as it cools (a trick used to get negative camber on live axles is to run weld along the top!).

Alistair

[oldnut45]

Has anyone fabricated this beam and have they encountered any problems? As the beam is to be hot dipped galvanized after fabrication should allowances be made when welding the outer plate fixing bracket to ensure it will "fit" over the channel beam as there will be the thickness of plating to consider?

Graham

[ACourtney]

I have had some Metro and Mini subframes galvanized and my experience is that the clearances don't change that much. However, sometimes the surface finish is not that great - seems to be worse for galvanizing done in the winter months - and I have had to file smooth the areas where the rubber seals on the fulcrum pins seat. Put that another way - I failed to smooth the area once and the rubber seal broke before I had got as far as installing the subframe assembly onto the car.