A challenging few days this last week.
First off my attempt at PVA release on the molds came out really bad on the first go, I was too greedy with trying to put down too much in one pass and ended up with runs of PVA.
So I waited for it to dry and peeled it off - start again!
The second time I was also more careful with making sure the mold was absolutely clean and free of fingerprints or any other contaminate as another problem I found out the first time was any kind of contaminate will make the PVA not stick properly, one fingerprint can ruin the whole thing.
It turned out good the second time so it was time to cut out some carbon and get laying up.
I had a bit of a nightmare here with the layups. Not exactly sure what I'm doing wrong but maybe I should have put each layer of fabric in the mold and wet them out one at a time. As it was I did my usual method of wetting out every layer on a plastic sheet template first then cutting that out to shape and putting the whole thing in the mold in one go.
Doing this I found the carbon as one complete 4 layer piece did not want to conform to the shape of the mold very well - certainly this was the case in the front area where there are a lot of tight curves to go around.
Using a roller and some more resin I was able to finally get it to conform and stick to the mold.
The next day I noticed that a few air bubbles had appeared - too late to do anything about that now - I will have to fix it up later by filling in the low points with micro. Not ideal but as I've invested £300 worth of carbon and 2 days of work into the parts it will have to do.
As you can see the two halves are laid up separately - then trimmed down to the edge and finally I will bolt the two molds together and then reinforce the join from the inside - more about that next week.
The other little job I got done was building up the seatbelt blocks underneath the cell - as you may remember I found my seat belt did not tighten up quite enough - so I've extended the blocks underneath by about 40mm so this should be more than enough to take out the slack.
I found the lap belt to be much too long to be honest - I don't know why it is supplied that long - it could be easily 50mm shorter and still accommodate all pilots no matter how fat!
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| Two molds bolted together |
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| PVA release done - second time lucky - and a centre piece being laid up for the front of the cowl. |
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| Wetting out using a paint roller for the resin - much easier and faster than a brush. |
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| Top half done - what a nightmare! |
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| Onto the bottom half now. |
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| PVA release has shrunk to a nice smooth finish here. |
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| Lower half done - even more of a nightmare - had to cut it an overlap in several places. |
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| Top half trimmed out and peel ply removed - a few air bubbles here and there - not good. |
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| Seat belt block extended with carbon - just needs finishing with a thick layer of resin now to make it smooth. |
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