8 replies to this topic

[gaspen]

Hello

Mk3 Mini with twin bolt front sf. I measured diagonal from the rear of the front mounts to the front of the rear mounts. One shows 1607 mm, other is 1614.

Is this difference too much or managable later with suspension adjustment ?

Nothing is welded yet so i could adjust here and there but it looks that everything is its place

[Spider]

That is quite a difference and I'd be looking for where the error is. Depending on what part of the subframe you are looking at the build tolerance was either +/- 1/32" 0.8 mm) for the mounts to +/- 1/64" (0.4 mm) for the suspension pick up points.

[DeadSquare]

They were never very good.

 

I once made an aluminium sump guard, taking the dimensions from an Abingdon "Acropolis" Special tuning one, that went all the way back under the gear remote to the seat cross-member.

 

I struggled under the car, but either one end or the other (or both) didn't fit.  As the engine was out, I started measuring and the subframe was out of square.

 

I dropped the subframe, thinking that I could get it under a press, but it wouldn't fit, so I thumped a corner down hard on a roadside curb a few times until it was 'near enough'.

 

To my great relief, it still fitted in the car, and, the sump guard all but lined up.

[Spider]

Here's a video clip on how the front subframes are made. I think you'll find it impressive;-

 

 

[absx2]

I`ve " straightened " one or two along similar lines to DeadSquare`s by getting the diagonals matching.

[gaspen]

After some measuring I found my stupid mistake : the two sides of the floor panel were not aligned lenghtwise 

 

 20240619_112217.jpg   26.67K   0 downloads  20240619_112221.jpg   24.79K   0 downloads

 

Here is what it looked like before. What you see is a DIY measuring tool 

 

 20240619_103601.jpg   25.67K   0 downloads  20240619_103652.jpg   32.14K   0 downloads

 

...and after some hours of cutting the floor and welding into correct place :

 

 20240619_141247.jpg   30.95K   0 downloads   20240619_141211.jpg   48.09K   0 downloads

[Spider]

Good work !

I know all too well, it can take quite a bit of time just finding where these errors are.

[gaspen]

Hello

 

I still have some issues. 

 

Finally I welded the heel board to the floor panel. Now the diagonals from front s/f rear mounts to the rear s/f front mount are equal, that's okay.

 

I've made an other measurement for checking : I've clamped a long spirit level to the front subframe and measured the rear s/f front mounts from that line

 

It shows 15 mm difference beetween the two sides. I measure the center of the rear trunnion's hole.

 

What more shoud I check ?

 

 20240728_173112.jpg   80.62K   4 downloads

[gaspen]

Solved 

 

As the front s/f is fixed stable I can "rotate" the floor panel around an imaginary vertical axis. In this way the FR-RE to RE-FR diagonals remain equal, but I can alter the distance from the foremost points.

 

I just marked the final positions at the doorstep for the final assembly