Stretching the Hood

[grandpascot]

A quick question. I am about to fit my vinyl hood. With the material warmed can someone please give me an indication as to how much I can expect the material to stretch.

Thanks

Mike

[RobThomas]

Tough one.

It is somewhat dependent on the weave of the cotton fibres in the PVC moulding. If the material is naturally very stretchy then maybe you'll get more than 1cm but it is hard to say. I found almost zero difference on our Mohair hood on a sunny day so I guess it has almost no give at all.

The only thing I can suggest is to make 2 chalk marks on the hood fabric when cold and then stretch it out. After heating it again, see how much further it will stretch. If you have way too much spare material round the front of the hood you might be able to trim off a piece to experiment with? Hopefully you won't cut off too much.

The only other option that springs to mind is to run a series of temporary small nails and some weak glue and have a trial fit session before knocking the final pattern of nails in.

[DAVIDMCCULLOUGH]

I fitted a vinyl one some years ago following the instructions in Linsday Porters restoration manual. It suggests putting a blow heater inside the car to make it more stretchy. I fitted it along the wood at the back with staples, flattened it out and a few staples on the front and then left the heater in place long enough for a cuppa! I cant tell you how much difference it made but I know it made it easier to stretch and pull and when fitted it didnt sag. Once I was happy that it was all in the proper place I tacked it in and removed the staples.

[grandpascot]

I was principally asking the question because having never done anything like this before I was concerned that I might overstretch the hood and it would split.
I have fitted the back and provisionally stretched the hood under heat as you suggested. I wasn't able to tack it yesterday so I checked my marks this morning and found that on cooling the hood had shrunk back a little over one inch.
I assume that once all tacked in place the hood can cope with this sort of shrinkage without any splitting.
I'm also looking for a finished hood that shows no sag.
I'm hoping to be able to finish tomorrow.

[mogbob]

Good luck with the finishing off tomorrow.
Don't be tempted to fold it down straight away , once you've finished. Leave the hood " up " to " settle " into the stretched position for a few weeks.
On colder days initially, you will have a bit of a struggle to get it up easily but that's far better than having loose fabric flapping in the breeze. It will get better with use and the Summer is coming !
Bob