Matty's Marvelous Modular Monstrosity

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Foundationer

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Last day of holiday and my colleagues are annoyed that I'm getting big packages delivered to work! In this case a 250m bobbin of carbon pultrision! Gonna have a bunch of stuff to get on with when I'm back!

IMG-20190725-WA0008.jpg
 

Foundationer

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10mm x 1mm

Not 100% sure how I'm going to turn them into bundles and make them into a spar yet. Glue them together then incorporate them in the spar, or do it all in one operation?
 

Foundationer

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Anyone got a ballpark minimum thickness for carbon at a trailing edge so you don't slice yourself open on it and it doesn't crumple as soon as you look at it? 1mm? I'm thinking that my 2*265gsm will be really thin.
 

Foundationer

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Today I have mostly been battling Solidworks... Black is carbon / kevlar / carbon. Red is crash reinforcement: Rollover protection set into the bulkhead behind pilot (also behind pilot: 100kg of LiPo batteries(!)) cockpit rails of uni carbon, kevlar and foam and a front bulkhead. That's about as far as I've got turning it all into 3d.

All the white stuff will be non structural turtle deck / aerodynamic fairings. And then there's that huge cockpit transparency... I really should think about how to actually make that...
 

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pictsidhe

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Anyone got a ballpark minimum thickness for carbon at a trailing edge so you don't slice yourself open on it and it doesn't crumple as soon as you look at it? 1mm? I'm thinking that my 2*265gsm will be really thin.
Chopping off the last 1% of airfoil is a common rule of thumb. Neglible aero impact.

I know exactly what you mean about figuring out how to make stuff. A design is no good if you can't turn it from paper into reality.
 

Foundationer

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Two elevator halves ready for whatever the next bit of the process might be. I suspect it's trimming, joining, wrapping some more bi-ax over the join area, cutting out some bits for hinges, filling, sanding, painting, mass balancing... Basically done then! 490g each which is sort of about right. Massively overbuilt and as minimal as I could make them all at once.

Flaps follow the same construction methods and are much bigger so getting it all sorted out on the elevators first seemed like a good idea.
 

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Foundationer

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A year and a half since my last post about this thing. Who'd have known having a kid/covid could be so disruptive?

I'm going to pick this up like a bad soap who lost the lead actor, replaced him with someone else and just pretended it never happened.

The render's the old one FYI...
 

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Foundationer

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Now I'm back at this properly I've got questions & I know you guys have answers...

What's the most straightforward way of securing a centreline hinge pin in a solid foam core elevator? Bonus points if there's a really foolproof way of getting them perfectly aligned.

Centreline hinging allowed me to make the horizontal tail upper and lower in the same mould else I'd have hinged it somewhere more sensible.
 

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narfi

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I don't know how it should be done, and I have no experience, but I like thinking about such things.....

Could you wrap the ends with carbon as well with a small block of Teflon to act as a bearing area where the hinge pin should go and instead of securing the pin to the elevator, secure it to the bracket on the horizontal with just the end of the pin sticking into the end of the elevator?
 

Foundationer

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I don't know how it should be done, and I have no experience, but I like thinking about such things.....

Could you wrap the ends with carbon as well with a small block of Teflon to act as a bearing area where the hinge pin should go and instead of securing the pin to the elevator, secure it to the bracket on the horizontal with just the end of the pin sticking into the end of the elevator?
There are these plastic bearings that I might use in place of bronze bushings so I'm already maybe heading in that direction!
 
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Foundationer

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I got all the big bits out from under the build table the other day and laid them out on the grass. Gonna need a bigger garden. I'm almost at the stage where I start having nightmares that none of them fit together!
 

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