The online Classic Community


Spitfire MK IV Restoration project - Part Six -

With the old paint, oil and rust removed from the chassis it was time to assess the damage. There was nothing too serious apart from the front cross member where the passenger side ¼ panel attaches, which was totally shot.

The there were a few small holes in the rest of the chassis but manly in the outriggers but not serious enough to warrant the removal of the whole outrigger and replacement with new.

Outrigger 1/2 repaired  Outrigger repaired  Outrigger painted

The corroded metal was cut out into a regular shape. Once the metal was removed the area around the hole was cleaned up and the inside of the outrigger checked for any more corrosion. A piece of metal the same thickness as the outrigger was cut to a rough size and then carefully filed down until it was a good fit in the hole in the outrigger. I used some strong magnets to hold the new piece of metal in the hole in the outrigger to ensure that the fit was flush. When I was happy with the fit I tacked the new piece in a few places so that I could remove the magnets. I then completed the welding of the new piece ensuring good penetration all the way round. Once the welding was complete the weld was ground back so that the repair was flush and almost invisible. To check on the quality of my repair I painted a couple of coats of Hammerite and was very pleased with the results.

There had been a couple of repairs made to the chassis by a previous owner and to be honest the weld looked like it had been thrown on, there was far too much on and the repair looked like it had just been plated over without the rotten metal being cut out.
Out came the angle grinder and I cut out the previous repair back to good metal before replacing with new.

Poor Patch Repair  Patch Repair Nearly complete

The one area I was not looking forward to repairing was the cross member for the ¼ panel. One way to repair this is to replace the whole cross member with a new one but I did not want to replace the complete unit as the boxes where the bonnet attaches were in good condition and the bonnet fitted well and I did not want to disturb this. I was going to try and fabricate the replacement for the corroded section but it is quite a tricky section so I bought the complete cross member to cut down for the section I needed.
The old adage if measure twice cut once came into play in fact I think I measured at least twenty times even then when I cut the new cross member down to size I left extra material on to be filed or ground down a bit at a time until a good fit was achieved. Once I was happy with the fit the paint was removed and the area cleaned up. With the help a couple of clamps and magnets the new section was lined up and tack welded into position. I was amazed how easy it went together and I was able to continue the weld all around the section and I was very pleased with the results.

Quarter Panel Before Quarter Panel Missing  Quarter Panel repaired

With all the repairs made to the chassis I had to paint it as the chassis would have to spend some time outside under a cover while the body work was repaired. I will eventually paint the chassis the same colour as the body but needed some protection for the coming months. I decided to give the chassis 2 coats of Hammerite one coat of black and one coat of light blue which is very similar to the final body colour so that I would not miss any areas on the second coat. It takes much longer and much more paint than you expect to paint the chassis as there is so much surface area with all the vertical and horizontal surfaces.
With the 2 coats of paint on I left the paint to fully dry for a week or 2 before I filled all the box sections in the chassis with cavity wax.

Chassis Ready for Painting Chassis Half Painted

Completed Chassis

In the next section I will build a frame to support the body while the panel repairs are made.