Hi all
This is my attempt at a Praga Mignon. Praga were one of the so called 'Big Three' of the Czech motor industry along with Tatra and Lauren & Klement (later Skoda Auto). The Praga Grand was the official staff car of the AHE but in my mind this vehicle looked pretty ordinary. It's smaller brother the Mignon however was a bit more interesting, especially the sporty version. It can be seen here after the white limo
https://images.app.goo.gl/XjYdo5JtsMMh1KV36I have done the first part like a tutorial because I made the body out of papier mache and having learned to use this stuff thru trial and error over the years would find it a shame to not pass the technique on.
I first carved the shape out of dense foam as you would with balsa if you were push molding it. I then painted it with vaseline so the mashe wouldn't stick. I next mixed up in the liquidiser some paper, flour, water and a bit of bleach to stop it going mouldy. I have in the past put PVA in the mix but left it out this time (just hope the wife doesn't read this, she would go apeshit if she found out I have been putting paper, glue and bleach in the food mixer). Next it goes in the microwave so the flour releases the starch, it should be the consistency of porridge. When cool I spread the paste on the mould quite thick, this will take a day to dry but will shrink incredibly thin. This will make the inside very smooth. I next put on three layers of regular papier mashe using small pieces of torn newspaper and a runny flour/water mix heated for the glue (oats and rice also work). Although three layers went on because of overlapping on each layer the wall would actually be about 5 layers thick in most places. Again this is left to dry and shrink in the process. Finally one last thick coat of papier mashe paste left over from the liquidiser to make it more even on the surface. If you are wondering why I don't just plaster the whole thing in 2 or 3 layers of paste it is because I found that on open box structures like a convertible car this warps like hell over time, regular torn newspaper papier mashe retains it's shape nicely. Next I put a few spots of filler on parts needed and finally a couple of thick coats of white acrylic paint (used as filler too). The whole thing was wet and dry sanded, when I went down to the paper I painted it with spirit based varnish to stop the paper from fluffing. Once happy this was smooth I cut out the open top and picked out the dense foam. On filing around the edge I did mistakenly stick the point of a round file thru the side but managed to repair it with papier mashe. I now have the bodywork done. This took about three weeks and would be impractical if there were time constraints but I did this between other things and in reality it equated to about 2 hours of bench time, probably about the same if you did this by push molding.
So that's my alternative to push molding two halves, gluing them together and making good or 3d printing. The cost of materials is almost zero and the thickness of the walls is very thin.
I am undecided whether or not to cut out the doors or just scribe thier lines however I will tackle the chassis next.
Thanks for looking in,
Alan.