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Titanium clutch push rod idea now canned because I cannot accurately work out where to put the ball bearing in the system. Also, when I finally finish it I would like to take the bike to the south of France to see my mate resident out there and I do not want to have to carry the original push rod in case the titanium one wears out.
Last couple of days have been spent on the moulds, I managed to get the shorter of the belt cover patterns out of the mould but not without destroying the original rubber/plastic belt cover and with a bit of damage to the mould where too enthusiastic use of the wood chisel eroded the crispness of the edges.
I think the reasons for the difficulty in removing the patterns form the moulds in most cases was to do with mechanical locking, i.e. somewhere on the pattern where the sides were parallel or where there was a nib that prevented the mould withdrawing from the pattern. The other significant problem with the patterns was an inadequate seal between the edge of the pattern and the base layer of polypropylene sheet allowing the gel coat to get between the two and then sealing the pattern into the mould. Finally, I think there is a possibility that the application of the release agent to the pattern some few days before the gel coat was applied might have contributed to the difficulty in removing them, i.e. the spirit base to the release agent evaporated off taking some of the active ingredient to the release agent with it, but that is merely conjecture on my part.
This does not augur well for removing the carbon fibre pieces from the moulds when I eventually get round to making them. The last couple of days have therefore been about repairing the chisel damage to the edges (by filling, rubbing down and polishing the edges with progressively finer wet and dry) and removing any possible places where mechanical locking could possibly occur. The other strategy will be to make the carbon fibre pieces with only one layer of carbon fibre before removing it from the mould. This, I hope, will ensure that the CF workpiece is still relatively flexible and therefore able to be eased out of the mould. Second (and third coats if necessary) of CF will be applied with the piece outside the mould.
Utopia: Shredding glass fibre is undoubtedly best for ease of application (and for the aesthetics of the finished mould) however it is very difficult to work out once the glass has gone translucent how thick the layer you have applied is. My cutting into strips loses the strength of the longer fibres but possibly gains on certainty of coverage and uniformity of thickness across the whole piece.
To date I have not used a roller because all of the moulds have been too small/fiddly and required a brush to stipple into corners anyway and using a roller on the relatively small flat areas would have just meant something else to clean afterwards. I think the tank and seat moulds will get a roller treatment just to ensure good lamination. I cheated and bought my roller from EC.
Interestingly, Easy Composites recommend the use of a plastic scraper to apply the epoxy resin to the CF when wet laying CF to ensure the resin is forced between the fibres, probably because I think the epoxy resin is a bit more viscous/glutinous than the polyester resin
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