mikec
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Kind of like I showed back in post #16.
AV bay all-thread
- Thread starter Tonimus
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ChrisAttebery
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I've been considering this exact idea for a while. The problem I see is that you'd need a large tab surrounding the attachment points. Imagine a .500" hole with .75" of G10 surrounding it at each end of your 54mm sled. We could use a thicker sled with most of the center milled out to achieve the same weight and strength though. Any material inline with the attachment point holes is just added weight anyway. So, we could use a 3/16" X 1" sled with and mill it into an I-beam profile leaving 2x .187" x .375" bars attached together with a .060" web between them. You could make a simple delrin block on each bulkhead and screw the sled to the block to keep the bulkheads in place.
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My 29mm SMART sleds are specifically for this type of shock cord attachment.
In my particular implementation there is a place to wrap the Kevlar around a nut for extra strength.
Fiberglass rod? That is interesting. It should be strong enough.
jcato
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Yep. What I was trying to resolve was making the same thing without any metal involved.
-- john.
jcato
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Might need to put together a sketch -- I followed about half of that (the first half), but when you got to "most of the center milled...", things started getting cloudy
-- john.
jcato
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Chuck, are you responding to my post?
If so (or for others), here's a pretty good place to get some of this kind of stuff...
https://goodwinds.com/clearance/clearance-solid-fiberglass.html
... and here's the general link for the 'Clearance' items...
https://goodwinds.com/clearance.html
Back up to their homepage for a wider selection.
I've bought off their 'clearance' page many times and there's some pretty good pricing (and choices) there. Shipping? Not so much (recently got some 3/16" carbon tube (12x30"), + some 1/8" carbon rod (30x24") and some .330" f/g tube (36x11") and the shipping was $18 (one 3" tube)). May be reasonable, but I was figuring in my head something around $12, so it was a little more than I was expecting.
-- john.
Aaaaaah, why not just stick the EggFinder in the metal all thread ebay and put a bulkhead socket for the antenna? Could use a short cable to a linx antenna and zip tie it to the drogue/apogee shockcord?
Sure the range might be down on the up side but once the drogue/antenna deploys should be no problemo.
I have a Beeline GPS tracker that rides in the aft end of an ebay with a bulkhead antenna mount that uses a spring antenna: https://www.ebay.com/itm/SMA-M-Male...610?pt=LH_DefaultDomain_0&hash=item1c3f3aecd2
They don't make 'em for the ISM band though
Sure the range might be down on the up side but once the drogue/antenna deploys should be no problemo.
I have a Beeline GPS tracker that rides in the aft end of an ebay with a bulkhead antenna mount that uses a spring antenna: https://www.ebay.com/itm/SMA-M-Male...610?pt=LH_DefaultDomain_0&hash=item1c3f3aecd2
They don't make 'em for the ISM band though
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taiwanluthiers
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I'm wondering, how about using the all thread as antenna? You know connect a copper wire to the all thread, and then that goes to the antenna socket.
What about using the sled as the coupling like I have done in my Apache nosecone?
You could perhaps use a remarkably similar method in your sled. Eye bolts would attach to aluminium parts fixed to the sled. The G10 takes the axial forces.
Steer clear of the nylon allthread. Fails far too easily.
If you wanted to use metal, but reduce the amount, you could use custom bike spokes. They are available in custom lengths, with rolled threads for extra strength (2-56 imperial thread). You can go titanium if you like, which have a breaking strain of around 280kg each (for a 2mm spoke).
You could perhaps use a remarkably similar method in your sled. Eye bolts would attach to aluminium parts fixed to the sled. The G10 takes the axial forces.
Steer clear of the nylon allthread. Fails far too easily.
If you wanted to use metal, but reduce the amount, you could use custom bike spokes. They are available in custom lengths, with rolled threads for extra strength (2-56 imperial thread). You can go titanium if you like, which have a breaking strain of around 280kg each (for a 2mm spoke).
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