Especially given that the strength of the frame is from how bonding of cloth and resin *around and in between* all Nodes and Pipes, not the Pipes and certainly not the PLA that deforms above 60C. Initially my idea was to remove the masking tape on each Node but having now seen quite how much gets down into the area around the PLA instead of around the ends of the bamboo and PVC pipes i think *deliberately* wrapping layers of masking tape around is a good idea, not least to significantly reduce weight. Ok so this is the very first wrap session, a few layers on each node, you get the general idea of how this is going to go: QTY 135 Nodes, each one probably 3 metres of 50mm wide Kevlar "belt", it's a hell of a lot of kevlar and resin, and that's just the Nodes: the pipes need a minimum 3 layer wrap as well. that comes later but is already part of the CAD. The swingarm will be attached to the backbox, and there is a macpherson-like housing for the top of the suspension which will need some steel reinforcement connecting to the swingarm area. rear wheel arch is in the middle right part of the photo. the rear assembly is front-down, view is from left side, the "back box" (behind occupants) is on the floor and the top line of the rear bumper is pointing upwards. in the meantime here is me complaining about hotglue Įdit: here. will edit and add a couple of pictures next week. what is particularly good is that once set the bamboo sticks out entirely freefloating in midair without falling off the Node. i was somewhat reticent to use it because it is so much stronger and could soften the PLA but it works well including the usual dismantling after a mistake. I had to scoot to FOSDEM2023 so didn't get a chance to complete the rear section, but managed about 30% remarkably quickly, by switching to hotglue. beyond that point the strength of the glue and masking tape is completely irrelevant. Remember that all i need is for this glue and tape (and occasional string loop to create compression) to hold together long enough to get the Kevlar / Hessian / Flax / Hemp cloth and Epoxy around it. epoxy would once dried be virtually impossible to get it to come loose a bit under the masking tape. The other reason for using the rubbery glue is that sometimes the nodes get off-axis: the pipes are not flush perpendicular to their joint-seat. I just found (36 hours late) the first major assembly mistake (2 nearly-the-same-length pipes swapped) and it is relatively easy to correct by digging in through the masking tape, scraping the rubbery glue until it gives way, and pulling the pipes out. Question: why the hell would anyone do that? why not use superglue or epoxy? answer: because undoing mistakes with a hard glue is a cascade of catastrophic modifications and damage, getting pipes out from their nodes it would actually be better to cut and splice. then using painter's masking tape which is a pig to work with, it doesn't properly stick except to itself (which can be exploited with the right kind of wrapping technique). I'm using loctite extreme glue here at this early phase, *not* the loctite extreme epoxy: the rubbery clear stuff, and tons of it (about a 2 to 3mm puddle surrounding each bamboo pole, i've got through 7 tubes already and i am only about 1/2 way done).
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