Has anyone made a line holder for a trike that is dimensionally correct for the version 2 hoop? I’ve seen some but they don’t match the aerodynamic shape of our 28mm hoop.
Not really an answer, but I just saw this on an ICE trike
Guy said it was easier on sheathed lines than the little gap in plastic molded holders
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DO NOT attempt to mount the SP140 on a trike. It will not work without extensive modifications.
The cage will collapse into the prop and destroy it along with the netting and several hoop connectors not to mention the bend netting rails.
I just wish someone had warned me about this before I tried it.
Agree with need for reinforcement! Some of us do not have legs to avoid the trike, so I press on with fiddling - will fly it someday!
I got this double hoop reinforcement from Superfly - still haven’t cinched it all the way down with zip ties (option of just Velcro straps seems far too loose.)
Ironically my healing knees will allow mellow free flight here in SLC, but not to land with the weight of PPG - so trike mission stays open, as I do want to travel and not always be dependent on free flight conditions/launches
Could you please explain the issue in a bit more detail? What part of the cage/frame can fail? Thanks!
Was this with the red connectors which you printed yourself? Sp140 hoop connectors are SLS printed (laser sintered nylon). They are of the upmost quality and such quality can NOT be achieved with a desktop FDM printer.
The standard hoop connectors are tough but too brittle (low tensile strength). I accidentally broke two of mine before I gave up on them. The hoop bends during assembly and transportation. Instead, the connectors printed with PETG, the right layer orientation, and a stronger core screw are, in my opinion, much more durable and reliable. I have replaced all of mine and do not see going back. Plus, I think everyone should have a spare set, but paying $145+shipping for these is a bit much. I have redesigned them for a screw 40% thicker and improved tolerances, and they’re holding on great so far.
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Good job with those prints. I like that you adjusted the tolerances and switched to a thicker screw. I bet the larger screw size has more to do with increasing the strength than switching to PETG though. I use PETG for almost everything I print and it certainly tends to be a bit brittle in general.
What did you do to break the parts and bend the bolts? Are you tying the motor down by the hoop? Or bending back and forth too much during assembly? Or did you have some rough landings?
PETG is definitely not a brittle material, but SLS used in the standard hoop connectors certainly is. One of the original connectors broke during assembly and another during transport in the back of my SUV.
Did any of your original connectors have the nuts installed? I just realized none of mine did:
So, I just broke one of mine while assembling it because I had two of the spars swapped and accidentally bent it to breaking point before I realized my mistake. If the nut was in place it would have strengthened it but perhaps not enough to prevent the break. I actually fixed it temporarily just by adding the nut to hold the broken piece in place. Later I drilled the hole bigger and put a 5mm bolt through it. I might do that to the rest of them to make them stronger but for now I just installed the nuts. Like I said before, I like your idea of using a bigger bolt.
SLS nylon is certainly brittle compared to regular nylon, at least in the case of the SP140 connectors. They seam more brittle than FDM printed nylon as well. I expected SLS to be structurally superior to FDM but I was wrong, at least with these parts.
I disagree about the brittleness of PETG. It’s a pretty strong material and I use it a lot but it will snap if you bend it and therefore I classify it as brittle as opposed to flexible. It’s all relative though so no need to argue. For comparison, FDM nylon is more flexible and will bend more before breaking if it breaks at all. I do agree with you now that these SLS nylon parts are more brittle than PETG but neither one will hold up without the bolt.
Ya we might do a bigger bolt by default ill play with the design a bit.
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