another quik update to those who where asking how to mold stuff.

ok, finished surfacing the bumper. next step is to card up some flanges. this needs to be done cause there is a return flange on the wheel arch and it wouldnt be possible to get the bumper out the mould if it was done in one piece.
flanges are simply cut from card and super glued in place



next step is to seal the card and any exposed filler, this is done with pva sealer, a few coats are applied to make a perfect seal



next you need to apply release wax, again 3 or 4 layers are advisable.



next is the layer of gell coat, this gives a good surface finnish to the mould. this needs to be left for about an hour (depending on the ammount of catalist)



i use surface tissue next. this is a fine material that makes a barrier between the gell and glas mat to prevent the mat pattern showning through the finnished gell surface. you can see on the tight 90deg corners ive also used loose chopped strand mixed with resin to put a nice radius on them so the mat can follow the surface easier.


its also easier to push into tight corners to prevent air gaps


the glass mat goes on next, for a mould tool it needs to be quite thick to prevent it distorting when a new bumper is laid up into it. (glass fibre gets very hot whist curing and it can contract and pull the mould quite a bit if its not strong enough.)
for this tool im using 3 layers of 450 gsm choppped strand mat.

this is the first section finnished.

il update with the rest of the process when i get chance to go down the unit and finnish it