Day 4ab&c. Messing around with teething problems. Main one (and least expected so last checked) was tacky tape that did not stay stuck.
Day 5. Infused the first half of the first tender hull. A few dry bits from vacuum close outs which were not a problem on the samples where the resin front spread across the laminate. Solution is a strip of infusion medium down the middle of the mould and one feed line instead of two.
Could have been fixed during the infusion by poking a vacuum source into the dry area, sucking in resin, removing the source and taping the hole. Uncharacteristically I decided not to risk the whole job for a couple of dry spots. Should be easy enough to fix them tomorrow, but it would be a lot better if it wasn’t required. The pictures were taken before the resin stopped flowing, the end result was not quite as bad as it looks. The other glitch was the not extending the feed close enough to the vac outlet. The samples infused 300mm/12” across the stack but today only 100mm. Not sure why but suspect the resin cured quicker than expected due to some pretty aggressive heating.
Resin used 15.8 kgs, 400g in the lines and buckets. Maybe 2.4 kgs in the spiral peel ply and medium leaving 13 kgs in 8 kgs of flax. I might have to work harder on getting the laminate tight in the corner of the mould.
Day 6. Repaired the dry spots by running a length of spiral across them and infusing. Not perfect but not far off. Photos show the extra length of spiral. Heated it, cut the materials for the next half hull then demoulded it. The plastic mould liner worked well. I should have plastic taped the mould edge but nothing a sharp chisel didn’t fix. The vertical looks good, I can’t lift it solo to see the horizontal surface.
Day 4. Flax samples were impressive.Thicker than the glass so stiffer and heavier as more resin was required. However the economics work as the flax is gratis. Flax is easier to work with in some ways, does not itch and is more stable as it is tightly woven. Hard work to cut will be good when the electric scissors arrive Hand laid a sample bulkhead as the pump was in use. Pretty rough but the method has merit. Will test it in the morning along with a sample join Cut the flax for the tender and prepared the mould. Infusion next.
Day 2 – 3. Assembled the mould for the tender (one side and half the bottom). Prepped an infusion of some flax and glass. To compare. No vac pump so infusion tomorrow. Flax rudder mould was not fully cured so put it outside in the sun. Sat it on a couple of rocks which indented it. Heated the affected area, put some weight on it and the bumps disappeared. As near as I can see it is about the same stiffness as equivalent glass weight but used more resin.
Infused 2 stacks of flax and 2of epoxy. Couple of dramas caused by using black poly pipe instead of clear soft pipe. Not only can’t you see the resin but when you clamp it the poly pipe splits. Plus it was 12mm and my biggest drill here is 10mm so the resin inlets were not as robust as they could be. Nothing a heap of tacky tape couldn’t fix. Pics show the infusion rate which is near enough identical for flax and glass but the flax uses more resin.
At 20C 300mm/12” is about the limit of resin travel with this resin. So 2 x spirals will work for the tender half hull.
Day off tomorrow, infusing samples for join testing on Monday might get the first half infused by the end of the week.
Day 1. Cleaned out the shed. Found 2 rolls of 400 gsm woven flax that we can borrow for the tender subject to some tests.