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Thanks Tim, I'm really happy I bit the bullet and went for the full floor. It was a difficult decision financially but its so well made and put together on a jig so you can trust its the correct dimensions.
Initially I didn't want to spend too much, this car is just mkII super deluxe remember.

Here's how I fitted the floor.

I found the subframe diagram from this site really useful, thanks mk1 performance.
I've never attempted to fit a complete floor before, this is how I did it, feel free to comment if I have messed it up.

I clamped a good quality long straight edge to the bottom of the front sub frame perfectly in line with the top and bottom arm mounting positions, with the bare front sub frame completely bolted into place I then measured back to the rear sub frame mounts on the heel board. Equal measurements both side gives you, hopefully parallels, equal diagonal measurements gives you square and eyed though front to back(2 long straight edges required, one on front sub frame, one in line with rear sub frame heel board captive nuts) gives you true or parallel underneath.
I used large callipers for striking centre lines and negotiating the lumps and bumps of the underside of the car where straight edges don't work and made up some small jigs to save tape measure reader error on my part.

It appears that the car is within 1mm between the suspension mounts but the upper body, I'm sure is nowhere near that accurate.
I deliberately didn't use the rear sub frame for reference as its rubber mounted, I've only got a non gen one as well and its way out on the correct measurements according to that diagram.

Here's a little measuring bar I made. It sits on the heel board and runs parallel to the floor along the length of the car. Its set to 599mm. Heel board to centre of first rear sub frame bolt hole.
It seems the pressing for the rear seat is not quite central on the heritage panel, I presume its supposed to be?
This really threw me off for some time as I assumed that as it was a heritage panel it would be perfect.
you can probably see in the photo that the centre line I have scribed on is not in the middle, its only a few mm but it really threw me off. Ignore the hydrolastic bracket, I welded that on and I welded it slightly in the wrong place.
I found the centre of the heel board simply by measuring between the rear sub frame trunion bolt holes and halving that measurement, that was easy and the M-Machine panel was made millimetre perfect according to the sub frame alignment diagram. Finding the centre of the boot floor/rear seat area was more tricky, I tried measuring between the pressings, totally wrong, even by eye. Then I tried measuring between overall panel size but wasn't convinced either so I used large callipers with scribing points to strike arcs from a point that I punched into the metal in the middle, in between the two holes for the rear trunions on the boot floor that never moved from their original position.
I don't know if that makes any sense to read.

I took the opportunity to paint inside the box sections with an epoxy paint, I've never used it before, it seems very durable and has great adhesion.


New floors finally welded in, the project turned a corner after in my eyes.

Great work ollie. Very nice . There's nothing wrong with plug and weld but a good investment is a spot welder . I purchased a hand held spotmatic a few years ago for £250 and it saves so much time and work . Looking forward to future posts . Well done

nice work


I think its easy to get confused when your scribing datum lines and the like. don't forget that there was a +/- 1/8" tolerance, so stuff does move around

I spent ages tweeking and tugging my stripy mk1 and finally got it to 1/16th corner to corner -= a lot better than the 1" it was when I started it!

godammit double post

Thanks for the advice swifty, I really should have invested in a spot welder. When I first started I was a little naïve and thought the whole job could have been done for a lot less than I have already spent. As I already owned a hobby type MIG I was reluctant to buy another machine. Its probably a bit unusual but I do quite enjoy grinding down welds, that being said it would have looked a bit nicer to have the spot welded finish.
I also have a 71 clubman that requires some work so will probably buy one. Do you recommend the spotmatic? I have no interest in electrics so know nothing, can you run one on an ordinary 13amp home plug?

Thanks for the reassurance on the measurements Rich, Its good to know I'm well within tolerance. I really felt the need to get something readable on the car with the centre lines and the like, most of the sub frame mounts and reference points had been bodged over the cars life. There wasn't really much left to measure especially at the back of the car.
I was quite comfortable doing this, I've spent my professional life learning setting out by hand, recreating the geometry for medieval architecture so already had all the tools for the job. Yes, I managed 1mm corner to corner but it took a lot of work and I had my Dad help me as the job definitely required a second pair of hands.

I found that a spot welder is only any good if the metal is super shiny clean and the tips are perfect, a lot of the smaller machines have such a rubbish duty cycle that they become useless after five min or so.


the only way to do it right with a spotter I think is to have a large three phase one that isn't running at its maximum like the single phase ones are. id even go as far as saying that one that has air assisted clamps would be best


the selection of arms you need to do a mini are also really expensive.

Ive got a nice, timed 240 one, but more often than not I just use my nice mig and puddle weld the panels, I find it far easier to control the heat, quality of weld etc etc - if the welder is set right there isn't too much cleaning work to do, and you can always fake the spot welds later if your that bothered.

the mig torch doesn't make your arms ache either!

Cheers for the info on the spot welders Rich.
I did actually consider using a die grinder or flattened drill bit to fake the spot welds but thought better of it.

I do wish I had access to a spot welder when I tackled the drip rails.
Initially I was going to leave them alone but I'm so glad I took them off and replaced. They were much rustier than I had first thought, there was a fair amount of rust hiding underneath.
It was just surface rust really. I started off using Bilt Hambers deox gel to clean up the steel but soon moved on to using a citric acid poultice as it works out much cheaper.
Once clean and rust free I used the MIG to fill any pits left in the steel and linished off smooth. After that I used phosphate spray just to make sure the steel was completely rust free.
Welding the new ones back on was a pain in arse with MIG as was cleaning up which had to be done with a carbide burr in die grinder or a 1mm cutting disc on edge.

I'm more and more impressed as this thread progresses Ollie.

I like the fact that you are repairing some of the panels rather than opting for the replace everything with rust option.

We are lucky in the Mini world that almost all panels are available, to varying degrees of quality. If you were restoring a less well served type of car you'd have no option than to repair the panels.

I agree with Rick with the spot welders. I have a hand held 240v welder and sometimes it works well other times not. Absolute cleanliness of the tips and metal is essential. Maybe the professional spot welders are more forgiving and probably more controllable. I use a combination of an older Migatronic, oxyacetylene welder and the hand held spot welder.

When Dad replaced the drip rails on his Mk2, he drilled holes along the rails and 'spot' brazed then on. Looks great with no need to grind back or anything.

Keep the pics coming Ollie

Hi Andrew, thanks, I really wanted to save as much of the original metal as possible. I've replaced a lot more than I initially intended. I thought I'd learn more making my own pieces and save money as well as I wanted to do the car on a tight budget.
Obviously I have spent a fair amount now on panels but I hope it will make a nice car when done.
My dream was to own mini again (after having not driven one in years) and thoughts were to try to build a rust free shell to base my project on.
I will modify the car slightly, hopefully tastefully and try to use period mods only.




I was very lucky with the roof panel, the paint had held up well. This was the worst rust I found in the gutter area which cleaned up easy with the citric acid.
Cleaning off old paint is more difficult these days it seems. Finding paint stripper that actually works was not easy. I finally found some called starchem synstryp that works ok.

I got a few boxes of 3M bristle discs on ebay really cheap as the spindle thread size was old/American 5/8" instead of euro M14, they work well for taking the last bits of paint and cleaning up the steel. A core drill thread adapter M14 female to 5/8" male gets them onto any 41/2" or 5" grinder.
Paint stripping inside was miserable at best, it stings a bit when it falls on your face.

I used the phosphate spray on the bare metaled roof as I wasn't able to paint immediately.
Its supposed to clean rust from the pores of the steel and hold it in a rust free state for a few weeks due to leaving a zinc phosphate on the surface. Also meant to promote paint adhesion but it feels so wrong washing it off/neutralising after with water.
I decided to sand it all off in the end before paint and as I'm using epoxy primer and keying the steel well I don't think any extra adhesion is needed.

The front end of my car was full of the usual mini rust and plenty of fibre glass bodge so off it came.
I wanted to save the inner wings but rust was almost certainly hiding in the seams. Having come this far it seemed silly not to replace, I think it would be a real shame if the rust started breaking through the new paint so I cut one off to access everything and clean it up before reassembly.
What a mess.

The bulkhead was covered in surface rust especially around the reservoirs.
I've cleaned it up with a citric acid held in a cellulose pulp, it does a good job given enough time of breaking down the oxidisation. Small parts have been put in a bucket with around 10% citric acid and water.
I made a new damper mount support in 1.2mm sheet and replaced the lower half of inner wing to bulkhead cross member in 1.6mm sheet as it had thinned due to the hidden rust.

The bulkhead cross member also needed a piece letting in as it was very thin.
I filled in a little bit of the pitting with weld as well, not sure if that was wise or worthwhile.

Yes I have a spotmatic purchased second hand from ebay and luckily with lots of arms and electrodes because there pretty expensive to buy . It's 240 volt with no timer , on 32 amp blue plug . Yes the metal has to be very clean . When you put the wings on its nice to see the spot welds .

That's a lovely looking finish you've got on your car, I hope to get mine looking something like that good.
I find electrics really daunting, I tend to avoid it whenever possible. Its probably the thing I'm least useful with, I wouldn't know where to start with wiring in a supply.
I remember I even struggled wiring in a rev counter in one of my old minis.
Cheers, Ollie

Unfortunately the cross member also had a crack where the engine steady is welded, I guess it was metal fatigue.
I wasn't sure what to do here. I considered just welding up the crack, in the end opened up the crack then made a backing plate in 2mm-ish steel, fitted it inside then plug welded it up.
I'm really not sure if it was a good idea but I thought it would spread the load. I checked the pedal box still had plenty of room before welding.

Here's a picture of the citric acid poultice I'm using to remove the surface rust.

I have spent the most unreasonable amount of time trying to fit the inner wing/flitch, I thought this would be easy being a heritage panel.
The pressing is really not good some of the holes have not been punched out, there were ripples all over it and no matter how I tried I just couldn't get it to fit while still lining up with the damper mount holes.
Is this normal? Has anyone else encountered this?
I centred the bonnet and fitted up the front end numerous times trying to get it to work, in the end I had to slot/elongate the four damper mount holes to get an acceptable fit.
This has been the most challenging part to so far, I decided to modify the lumps and bumps to make it a similar panel to the one on the car as it had a few differences.

Starting to look like a mini again

The panels are just resting there, I haven't welded it up yet. I was just to see if it will fit with a little persuasion.