FITTING A DOOR SKIN

We covered a lot of ground in our Midget restoration from the November 2020 through to the September 2021 issue, but one task that got left out of that report was fitting a new door skin. I promised back then to bring it to you in due course, so here it i

Door skins invariably rot along the bottom edges, because any moisture that gets in past the window rubbers tends to collect there and promote corrosion. Many models will also have another place where they are prone to rot, usually because a bracket or some other structure on the inside creates a moisture trap of its own. It is always a good idea to nip any emerging rust in the bud, before it has a chance to spread into the door shell or frame.

Often this rectification will involve welding in a repair section along the bottom part of the skin, and this is a task we have shown before, most recently on our Morris Minor project. For some classics such as the Midget though, complete skins are readily available and cheap (with prices starting from £55), and so it makes more sense to replace the lot rather than start welding in patches. The process is essentially the same, but for a repair panel you will have to seam weld and then fill a join part way up the door, while for an entire skin you have more work to do at the top by the window opening.

In both cases, the outer edges are formed in the same way, with the skin folded around the frame. There are usually just a few small tack welds too, in the case of our Midget three along the front edge and another three down the trailing edge, plus one in the middle along the bottom. So while you can separate the skin from the frame by sanding through the outer edge where that skin is folded round, care must be taken around these welds when removing the remains of the folded section because if they are not broken, trying to lever off the old metal will simply cause distortion.

The picture sequence shows the main steps to this repair. Once it was complete, Alan Denne applied some seam sealant along the edge of the skin where it is folded around the frame. He then wiped along the applied sealant with a drop of thinners, which left the sealant virtually invisible but sitting well inside the seam ready for painting.

1 This was the damage to our door skin – a section of rot at the front lower corner that had previously been repaired with mesh and filler.

5 Using a sanding disc in an angle grinder to separate the skin from the frame, go slowly and you will see the two layers split apart before you start cutting into the frame below.

3 And here is that same section on the old skin. You can see where Alan has made a start on drilling out the original spot welds holding it to the frame.

2 Complete new skins are freely available for the Midget, so that is what we fitted. This section goes under the quarterlight at the top.

6 We had a couple of spot welds that had penetrated through to the skin and needed breaking with a chisel, but then the skin could be lifted off.

4 In the end though, we decided that it would cause less distortion to run a cutting disc along to separate the outer skin, then remove the flange later.