GWR Toplight 7545 at Swindon Cricklade

Hi there.

Thought forum members might like to see some recent pictures of progress on the GWR Toplight 7545 at the Swindon and Cricklade see link

http://www.gmnabooks.co.uk/tcg/news25.htm

Some earlier news and photos here

http://www.gmnabooks.co.uk/tcg/news.htm

If you have any questions I will try and answer

 

Top quality looking job there!

 

Lovely work, but I do worry about the longevity of the plywood. The quality of plywood available these days, even the so-called marine stuff, is nowhere near as good as it once was and once water starts to get at it it doesn't seem to last long. I have often wondered about sealing it with painted on fibreglass resin - should help to get a good smooth finish as well. Has anyone tried it?

 

I thought I would comment on the plywood. When it was built the coach was covered with 3/8inch mahogany panelling and then later in it's life this was patched with steel sheet with often the wood panelling left underneath, sometimes even with the mouldings as well. Other times the thickness was built up with strips of softwood to keep the same 3/8inch thickness.

We had to re panel the entire coach and we decided to do this with Marine plywood. There are many different types of marine ply. The important thing is to make sure that all the layers of the ply are hardwood throughout as many cheaper plys with just have a hardwood veneer with the hidden layers being a much lower quality wood. We obtained the plywood from Timbmet in Oxford.

For the ends of the coach we went for a marine ply called Anchor khaya ( cost approx 60pound +VAT per 8x4 sheet) and on the sides we used gaboon throughout (i.e. every layer is gaboon) this was about 35+VAT. The logic being that the ends had originally rotted the most so we used the best quality here. Ideally we would have used the best quality all over but as with in everything in life you have to make the trade off between quality and cost.
I would suggest anyone wanting similar marine ply gets Timbmets catalogue as it covers the many different types/suppliers of marine ply and the properties of each.

As for painting it with fibre glass resin. I doubt we would do this, but I would be interested to see if another group had tried. We were advised by a well known painter (who recently painted Duchess of Hamilton) that the best thing to start with would be a very thinned wash of 'goldsize" thinned maybe 50% like water. He explained this would then completely soak into the fibres of the wood and make them hard as well as providing a good base for further coats of paint.

Incidentally the coach as originally built/restored used side panels that we found were exactly 2 foot wide making best use of the material.

 

As for painting it with fibre glass resin. I doubt we would do this, but I would be interested to see if another group had tried. We were advised by a well known painter (who recently painted Duchess of Hamilton) that the best thing to start with would be a very thinned wash of 'goldsize" thinned maybe 50% like water. He explained this would then completely soak into the fibres of the wood and make them hard as well as providing a good base for further coats of paint.

A preliminary coat of thin gold size as a primer is exactly what was done with teak panelled coaches at Doncaster, but I don't think it makes any difference for a painted finish whether it is gold size or aluminium primer - the important thing is that it soaks in and provides a good key. Fibreglass resin would seal and waterproof the timber far more effectively, particularly so in the case of any voids on the edge of the wood.

Incidentally the coach as originally built/restored used side panels that we found were exactly 2 foot wide making best use of the material.

Intersting logic, but if the coach was originally panelled in mahogany, does that mean the trees were grown to just the right size and shape to provide consistent 2ft wide panels?!

 

So far we have tried two different primers for coating surfaces underneath mouldings etc. First we tried a aluminum primer from Homebase but found this was useless. We were putting it on parts that had previously been cuprinolled ( eg frame parts) but found it never really dried properly. (Even a week later). At the moment we are using Screwfix red oxide as it coats well, is cheap and it dries quickly, typically in about 3 hours. Originally White Lead paste was used to coat the frames, roof canvas etc.

Potentially coating it with glassfibre resin could be a great idea, but I think some tests might be tried first. How long lasting would it be ? How well would paint stick on top. What would be the cost in resin ? Could the resin be thinned to make it more runny ?
I dont have much experience with this material

The panels being 2 foot wide may have been due to the equipment available as well as the size of tree trunks. In order to make the panels you would have to "convert" the wood into panels probably with a circular saw bench, so you would need the cutting depth of the blade to be a least 1 foot, making cuts from either size. The size of the thicknesser available (perhaps max 2 foot wide ?) could also have been a factor.

Here is a picture of the same coach before we started to show you how much we have done !

http://www.cs.vintagecarriagestrust.org/se/CarriageInfo.asp?Ref=235

 

heres a million dollar question...when you moving the coach onto '1 road' at the shed??? Just curious as the Taff is already across in your space, or so I am told and E34053 is waiting to move across?? Its turning into a carriage shed lol