Hi all, new to the site.

Ive played with fiberglass before and for this i want to make a female mould from part of my aluminium motorcycle frame outlined in red on the picture below. The mould would then be used to make a carbon fibre male cover to fit over including covering over all the bolt access holes and create lips round certain edges to act as clips for it to clip on. 

Ive read up on that process but I need to start with a completely smooth surface before applying the release wax and the gel coat etc. 
The surface of the aluminium is very slightly braised/dimpled which is in contrast to the rest of the frame which is totally smooth. If it was smooth then I could use the frame itself to make a mould.

Main Q is is there any kind of air dry clay/body filler I can use to create a completely smooth surface over the aluminium (including filling the access holes)? I would then apply the release wax to it and subsequently the gel coat and fibreglass.
I want to be able to remove the clay/filler after as I don't want to chamge/ruin the aluminium surface permanently.

I also understand that by using clay, I'd also need to apply waterproof damp seal and allow to harden prior to the wax.

Thanks in advance,
Phil

Theres nothing temporary that really works well, it's all a compromise. In my opinion, your best solution would be to cover the piece in release tape, but even that wont be great and you'll end up with edges from the tape. 

If it were me, I'd make a fibreglass copy that I could modify and smooth and paint until its perfect, then make your proper mould off that.

As said, there is no easy way of doing it.  You can try using the Mouldphorm PCL Low-Melt Polymorph Moulding Granules  as they are a lot more sturdy than plasticine or other temporary solutions.  

Then you can use it to make a splash mould, take a pattern which you can fettle and finish the shape before taking the final proper mould.


Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Probably obvious but, just in case, you will have to make a male mould otherwise the cover won't fit. So, make a female pattern/plug without altering the existing part, fettle this to your satisfaction, take a male mould from this with which you can make the cover.

An alternative method would be to simply make the cover directly from the part, then flow coat, sand and polish. This method was used by Carbon Weezel to make my bonnet and boot a few years back with perfect finishes.