I thought today I would see if I could solve the seat attachment problem but about 15 mins in I realised that the tank would have to be finally positioned first so I was forced to do the job I was not looking forward to – making the tank top marry as closely as possible with the tank bottom. This took nearly all day and I itch all over as the only way to do it was to use a Dremel with a cutting disc and use the cutting disc as a file. lots and lots of finely powdered CF everywhere.
It was quite tricky as the previous couple of days of filling and rubbing down had obliterated the seams in the mould which I wanted to cut to. After about an hour I realised that the best way to proceed was to trim the tank bottom to fit the top rather than trying to trim both. I removed about half a millimetre at a time continually checking where the high spot was. As I got closer to a good fit I also realised that it was no good just cutting to a line one had to cut at an angle that matched the angle the tank top met the tank bottom. Eventually it was getting to be a real struggle to get the bottom out of the top to make those finer adjustments. Overall I am quite pleased with the day’s efforts. Not exactly a gas tight fit but hopefully good enough to contain thickened resin to ensure a bond.
Before packing up I prepared the tank filler cap insert ready for bonding in tomorrow. When that resin is cured the both halves will get a coating of ethanol resistant resin before I attempt to bond them together.
Two other issues emerged in my general buggering about, a) I think the petrol tap may clash with a washer I welded to the inside of the frame to hold the rear light wiring loom and b) more problematic the top yoke hits the tank some way before full lock is reached – easy solution adjust the lock stops (but I do want to be able to turn round in the road without 3 point turning) or, more drastic, adjust the tank top to accommodate.
I made the pattern for the tank top with the forks out so I deliberately did not allow the pattern to be further forward from the top frame tubes than the Monster tank, but I made the pattern higher than the Monster tank, forgetting that the angle of the steering head causes the top yoke on full lock to infringe the space above the frame rail. Bummer!!!