Today started well then just went a bit South.
I got the second layer on the tank recess pattern and the fourth and last layer of fibreglass on the air scoop moulds.
I tried Utopia’s shredding the glass matt before laying it out and I should have listened more closely to him a long time ago. It was miles better than cutting into strips, much faster to prepare , much faster to wet down and a better and more consistent finish with the added bonus because it was so much faster to lay down I did not lose the last 10 – 20% of the resin because it went into jelly. Doh!!!!
I then spent an hour or so rubbing down the repaired mould for the Ignitech enclosure and getting it to a smooth and polished surface. I can only take an hour or so of this every day a) because it is boring and hard work and b) because I am losing top layers of skin from my fingertips again and they are becoming painful.
Then I worked on my fuel filler neck. I have to open the bore out from 43 to 45 mm about 11mm below the top of the filler neck in order to provide a positive step for the locking latch to bite. I cannot bore from the other end as that will be closed with a bridge to retain the filter in position so I ground up an old boring tool to give a 90 degree angle on the reverse side of the cutter. The depth of the step is vital to ensure the cap latches so that it sits firmly on the rubber seal and therefore seals the fuel in the tank and also allows the cap itself to sit flush with the outer ring.
It then occurred to me that the latch is steel and the neck and therefore the step on which the latch locates is aluminium.
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In the long run the aluminium would wear and the cap would not close. I spent a good hour pondering the solution and finally came up with machining an internal circlip groove and fitting a carbon steel circlip. I have now ordered 2 from Simply Bearings. I need to know the thickness of the circlip to get the right distance from the top of the filler neck so work has stopped on the neck until the circlip arrives. This solution will also involve filing away the inner edge of the circlip groove where the latch engages, this will not be easy but I think a Dremel with a rotary file should make reasonably short work of it.
Finally I spent an hour polishing the filler cap and ring to a reasonable finish.
Unfortunately, I came back an hour later to inspect my handiwork and the aluminium was already oxidising and had changed from a polished aluminium colour to a titanium colour. I will re-polish it and then buff it up and I will then have to clear lacquer it immediately, remembering to mask the key position.
When I got back indoors the postie had delivered my SS mesh which looks to be the right granularity to work but it is incredibly stiff considering the gauge of wire used. My original (probably hopelessly optimistic) plan to cut a large circle then punch a cup shape into the middle of it is quite clearly not going to work.
I think I will have to cut a 40 to 42mm circle for the bottom then a strip about 40mm wide to go round the circumference of the circle. If it was brass it would be easy as I would simply solder or braze the circle and the circumferential column together but with stainless I have no means of attaching the two bits together apart from epoxy resin and that may not last in a petrol (with x% ethanol) environment. I do not want to give up in the idea of an additional filter. Both brain cells are working overtime on this one, wackiest solution so far is to cut the circle about 5mm wider than needed and un thread about a dozen strands form the circumference then knit them into the columnar bit – a definite non-starter.