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Does anyone have any good pictures of what their rotisserie bulkhead connections look like? I still get nervous at the thought of using the roto-dip holes at the firewall and rear bulkhead holding the weight of the entire car! Do you just use the four little screws for the speedo housing to hold it to the firewall?

I don’t use the rotodip holes as the hole tends to put the centre of gravity too high making it hard to rotate a complete shell by hand.

Both of mine mount through the tower bolt holes and steering rack mounts in the front and the damper mounts and parcel shelf on the rear.

Doreen from M-machine told me that once you lose the geometry things get difficult with panel fit, so I went a bit overboard with the bracing. I had no jigs to put it square again, so as it had never been hit I was keen for it not to go out of square.

The car was rusty but gaps were ok, so I knew it was best to be careful.

The roof and both bulkheads were sound.

For a start, I used heavy 100mm square 3mm thick box for the spit. It was so stout it would not bend in the middle over a 4m span when I jumped on it in the middle (I am 16 stone).

I supported the car from underneath at the correct height for the rotisserie and kept all the weight off the spit until I had finished putting the car on just to be sure. It took me a day of welding to brace it all.

As far as the rear bulkhead went, I bent a plate up of 16th gauge and cut a large hole on the middle of it for the spit and drilled it for the bulkhead screw holes positions and then attached it to the car with M8 bolts, so it was solid. I then welded tabs to connect it to the spit.
As far as the front bulkhead went, I bolted stout angle to where the bottles bolt on through the existing bolt holes, then welded that with connectors up to the spit.
I was then able to weld pieces towards the front subframe mounts with tabs, triangulating them. I knew I was going to chop the whole lot off, so I wanted to make sure I didnt lose the position of these crucial 2 subframe mounting holes in relation to the bulkhead.
Moving to the rear I welded across the car to maintain the accurate location of the A and B posts with bracing for the door gaps as well. This was joined onto the spit too.
Finally I ran a piece of steel between the shock towers in the boot. This was bolted through the shock towers too and also welded onto the spit. I was worried my rear wheel tubs might end up it the wrong place and the shock absorber holes might be in the wrong place.
When It came to chopping the rust out, the M- Machine panels had arrived meaning I could crack on quickly without worrying too much about the geometry changing.

I built the car to the structure I had welded up inside it, more than how the panels wanted to go together.

When it came to fitting it all back together I didn't have any alignment issues.

Of course, once all the welding was completed I had to cut my frame out, but I felt it was worth it to have all 4 wheels travelling in the same direction!'

Tupers wrote: ↑Sun Jan 26, 2025 2:50 pm I don’t use the rotodip holes as the hole tends to put the centre of gravity too high making it hard to rotate a complete shell by hand.

Both of mine mount through the tower bolt holes and steering rack mounts in the front and the damper mounts and parcel shelf on the rear.

Same method of mounting used here.

I use the rollover jig supplied by the appropriately named rolloverjigs.com

I've attached two images below. One of the front and one of the rear.

The front has attachments at the top of the suspension mounts and at the base, through toe board holes. These are standard openings on the mini.
The rear has attachments through the suspension mounts at the top of the wheel arch. It also has attachments through the parcel shelf, which you may need to drill depending on the age of your mini. I had to drill them for my 1960 Mk1, for example
In both instances, I've highlighted the mounting points with green coloured circles.

OK well it looks like nobody uses the rotodip holes for use on a spit anymore! I am doing this a bit backward given that I have already done all the structural welding on the car and that was done on a frame based on the dimensions in the BMC/BL service manual. I am only using the spit to be able to do final small jobs like welding in new clips for the hydrolastic etc... When you don't have a continuous pipe running front to rear I suppose the only challenge is maintaining the same rotational axis between the two disjoint frames at the front and rear of the car.