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Balor
recumbent guru

Russia
800 Posts

Posted - 12/01/2019 :  14:01:34  Show Profile  Reply with Quote
Ouch, those two liners are huge indeed! Definetely unsafe in traffic and in gusty conditions... though Lazarus certainly looks very cool! (And must be fast... too bad there is nowhere to race them here).

Black Stallion seems interesting... But currently I really have no money, and borrowing some will detract from my own projects (cause I'll have to pay them back!).
If there would not be any takers, and after I'll deal with my own project (hopefully) I'll seriously consider buying if there would be anything left.
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Balor
recumbent guru

Russia
800 Posts

Posted - 12/12/2019 :  04:36:12  Show Profile  Reply with Quote
Made one lug from basalt/carbon fiber mix - seems very tough (laminate wall thickness 3-4mm), but I think I've overheated the mandrel when curing, overshootign it nearly to 90c when I left the oven unattented (should have used the multicooker, but I worried about water ingress), which is past HIPS HDT (80deg). It resulted in sides caving it somewhat, so I'll have to 'ream' it a bit, but tolerances are off by less than 0.5mm, should be salvageable. I guess I'll make sure I have no leaks and use the multicooker.

Next try - PVA. It seems extremely tough, but not very stiff (and damn expencive!) Same HDT as HIPS, so I should be more careful next time.
Otherwise, 'diy prepreg' worked just fine, minimizing my exporsure to uncured epoxy and mess.

Edited by - Balor on 12/12/2019 05:10:49
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Balor
recumbent guru

Russia
800 Posts

Posted - 12/12/2019 :  06:56:14  Show Profile  Reply with Quote
Printed a lug mandrel from PVA. It is more than stiff enough! But layer adhesion sucks - while there were no hissing and popping while printing, likely there were some water in it... supports came off mega-easily, I should be careful not to damage the mandrel itself.
On the other hand, I've barely managed to pry off the skirt from the bed, heh. Definetely not needed.
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Balor
recumbent guru

Russia
800 Posts

Posted - 12/13/2019 :  04:36:12  Show Profile  Reply with Quote
Btw, here is a good article about hybrid laminates:
https://basalt.today/images/Flexural-and-impact-behaviour-of-carbon-basalt-fibers-hybrid-laminates.pdf
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Balor
recumbent guru

Russia
800 Posts

Posted - 12/16/2019 :  03:10:24  Show Profile  Reply with Quote
https://imgur.com/gallery/gWJHUjE

About 50 50 carbon basalt by volume. Not beautiful, but will do (I'll wrap with a few layers of carbon to be sure on top once I'll glue them in I guess).

There are some small areas of dry fiber, I suspect I'm getting outgassing from interior air volume due to permeable 3d printed walls.
I'll need to suck the air out of interior volume as well - so I'll make a few holes on the sides and print infill using gyroid pattern.
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