Originally Posted by oxford1360
Andy, can you explain how you did the top bonnet louvres?
Are they stainless and glassed in?
I used the engine side panels to make a mould to reproduce the louvre.
for anyone that has not made fibreglass moulds they are very easy providing they are not to intricate.
your part needs to be as clean and smooth a possible find a good release agent and apply over the part. I use a PVA one looks a bit like washing up liquid drys pritty quick. use a form paint brush to get a good smooth Finnish anything you can see now you will see when its finished so do it right no runs.
your PVA is now dry so cut your fibre glass matting to size so your ready , I used CSM 650g 3 layers will give you around 5mm thick when finished. you can use a surface matting if you need to get into detailed parts.
now apply a gel coat give it a good covering on top of the pva it dose not need to look good a but try for a even thickness. I find thicker is better if you need to sand it latter you will not cut through the gel coat. but it will chip easy
step4, wait 10 min your gel coat should now be tacky to the touch mix your resin and apply on top of the gel coat first then start to layer matting resin matting it should be almost translucent when you have finished.
step5, your mould will dry to a mat Finnish when its ready to remove the more intricate the mould the harder it will be to release it. make some wooden wedges and work your way around it knock them in around the edge between the joint it will pop. wash off the PVA with clean water and away you go.
I am no pro at this its mostly been trail and error and utube so feel free to chip in if I am saying something wrong