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oops i did it again ,for whatever reason the flow coat and the primer did not like each other so I striped the rear end. made a small body mod at the same time. 1st test fit of my new dash fitted first time bit of work should be pukaI cant take all the credit for the dash. I bought one from chris just extended and modified it so it now goes down to the window screen all in one piece
oops i did it again ,for whatever reason the flow coat and the primer did not like each other
I couldn't see what happened to the primer, but guess it created in some way - could it be the wax content of the flowcoat?
Damned auto spelling changed reacted to created! crikey it changed it to reached this time,. but I saw it
looked like the flow coat was not 100% set when I primered over it . It looked ok till it was in full sun then you could see it starting to crack ,luckily just on the back panel and boot lid. could have been not mixed properly it was an old tin I have had for years poss gone off will never know all striped off now ready to re primer
GRP is strange stuff. I used a plug to make a female mould last year. a few days later I waxed it well several times and made a part in it - a couple of days later there was no way I could get it out and both the part and mould were scrap.
Made a new female mould off same plug, and this time I let it cure for 2 weeks. Similar prep with same wax, and when I made the first part it almost fell straight out.
It seems (reading on the 'net) that if (in this case the female mould) isn't fully cured then some cross-linking of molecules will still take place even with good release prep. If the weather's sunny I leave GRP (if in a good, stable mould that won't move) out in direct sunlight to cook it nicely
thanks for the info Mitchelkitman I have ordered in some gel coat did plan to take a copy off the dash when it's ready. but after your info think I will put it in the boiler house for a few days to cook it.
thanks for the info Mitchelkitman I have ordered in some gel coat did plan to take a copy off the dash when it's ready. but after your info think I will put it in the boiler house for a few days to cook it.
You need to ensure it can't move though, otherwise it could change shape in the heat- If it's in a (much thicker) mould whilst it cures then it's very unlikely to sag. If the part isn't in a mould to stabilise it, it may be best left for a couple of weeks in room temperature, maybe left in position in the car?. I know someone who had an old kit which had never been built, and the bootlid hadn't been stored in position. When he offered it up to the car is was clearly bent by a few inches. Held by wood and braced over a few months gradually bent it back to its correct shape. Some people advocate the blue PVA release agent, but I had a part stick using it (similarly made the mould a few days before) so I've never trusted it again. I've heard others have poor results with PVA also.
here we go test fitting the new dash so seats out dash out ,I worked out after some jiggling that I can keep the centre console so most of the plastic trims will then refit with minor work in the foot wells. on a plus side saves me loads of work re routing the switches I did look at changing it but keeping out weighs taking it out
I have ordered some Mirror Glaze 8 Paste Release Wax hopefully it should work for the one off I will be doing . thanks for the info molleur & Mitchelkitman
my release wax arrived yesterday so I got to work making a mold for the next dashboard. it was a bugger to get off the mold is thick around the front and corners so it doesn't flex. I have ordered some pva release agent for when I attempt to make another I am going in belt and braces for the next one wax and pva so it will hopefully pop out . I wish lol
Glass in a couple tube ports to the mould so you can use some compressed air to help it come apart. You don't need much air, a foot pump can generate enough pressure to separate the two if you haven't got a compressor.
I am waiting on parts from all over the place so having a play with the interior .made up some fiberglass door cars and started on the headlining what a pain
always seem to be waiting on parts at the mo so flicking between cars as they arrive. managed to get one dash in and almost complete,painted with textured paint.
after seeing the inside of a zagato without a centre console just carpet I decided the stock BMW console had to go. I made up a mold and set about making a new centre for the other car
test fit here's one I just made lol. I've extended the sides so it meets up with the rest of the trim so no gaps
some of the switches fitted ,hopefully will get it all in tomorrow and possibly get it painted
not going old school with this car I wanted mod cons it's got a dab radio and power charging points for phone etc
That's the great thing about Kit Cars - do what you want!
re the PVA, I've never had any luck with it (bits stuck in mould!) it seems so work as a good glue for me. I discussed this with one of the manufacturers about 5 years ago at stoneleigh and he'd also experienced the same.
use pva today on top of wax managed to pull the new part out the mold with no effort that's a first for me must be doing something right for a change.
PVA (Poly Vinyl Alcohol, not be confused with Poly Vinyl Acetate wood glue) mould release agent can be wiped, sponged or sprayed on to a wide range of pattern and mould surfaces to provide a very compatible and reliable release barrier for polyester, vinyl ester and epoxy composites.
That's re-assuring. I reckon i did something wrong when i used it! Can you tell the process you used, ie sequence of events and time frame, whether sprayed or sponged PVA?
TIA
I waxed the dash really filling any imperfections with wax then gave it a good thick coat of Poly Vinyl Alcohol (pva) let it dry in the sun . soon as it was dry applied gel coat .I've taken two more molds since both came off perfect no problem at all. I used school clue first time I ever did it washable pva which worked but run out so I mixed it with proper pva wood glue now that stuck like a bugger lol
