For a really “funky” fling, get some Durian or Ginkyo fruit…that may be the only way to beat the spoiled squid from last year…
Looking at the video from Tuesday, a net like you drew can probably snag the loose end of the sling. You drew it on the correct end as the crossbar with the roller faces away from the target.
Lol don’t forget we have to clean up what we throw!
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I delivered the v2 pouch today.
It looks like it will do the job. I also removed the v1 pouch and took it home to modify it. I will bring it with me to the park on Sunday morning. I will probably be there around 9:30 or 10:00.
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What pouch do you intend to use for this?
For funky fling was assuming a line will be directly attached to payload, and line will remain attached to payload and fly along with it, to avoid having to fit it in a pouch
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I have some 2" red webbing to bring if you want to make another. We may need several pouches.
Well, as much as I truly hate to be making another sling pouch tomorrow, it seems like a good idea.
And Brandon had a valid point that if we had another one, it should be a different material than what we already have.
How much webbing do you have? We need about 4 yards for one pouch. How thick is it? (I’m concerned about being able to sew it - I will need to sew through 4 layers in places). Is it tight weave (like the seatbelt stuff) or loose weave (like the first prototype pouch)?
I’m toying with the idea of going to Northern tools and buying a towing strap to cut up for a pouch. I’ll have to see if I think I can sew through several layers of it.
I think there’s some other material available in the box of miscellany - such as a reel of some 3/4" that was liberated from the freebie shelf.
Didn’t know you needed that much length. Its 2" wide and standard seatbelt weight, I have two 54" pieces. I can drop it off this afternoon.
The towstrap idea is good, too.
Ill be at the space today helping build a wall if you want to drop off a couple of bucks my plan is to make some sandwiches and snacks for tomorrow for the group. Nothing over the top but at least help people keep going. My guess is it will be a long day for them.
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V3 pouch is complete. It is towing strap - partly because we didn’t have any more seat belt webbing and partly because if v1 and v2 suffer a material failure, making another similar one isn’t a lot of help.
Here’s the design summary:
v1 Five close-together straps, seat belt webbing
v2 Three straps on 3.5" centers, seat belt webbing
v3 Five straps on 3.5" centers, tow strap
Letting one end drops shows that all three pouches release the ball easily.
You have and need to bring the v2 pouch. I have and will bring the v1 and v3 pouches. I will also bring a heavy duty hand-sewing kit if we need nominal repairs.
FWIW, I don’t recommend anyone try sewing nylon towing strap. It’s not a lot of fun. In retrospect, we might have considered leather.
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Got improved sling cables, connection to arm, new winch, and weights painted, big thanks to Allen and @ESmith for helping get things ready
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The arm snapped on full power throw, which chain reactioned into other things breaking (pivot wheels, rail track, pivot axle), to fix trebuchet and try to fire again at same weight assuming none of the frame or weight axle are bent:
Create new plywood arm upper, same design, add 1.5 inches to length
Add cable truss to front of arm with 2 1/8 steel cables running from tip of arm to middle of steel lower
Bore pivot wheel bushing out to 3/4" on bridgeport
Replace 8" pivot wheels with same or turn custom ones out of 8" aluminum round
Replace pivot wheel axle w/ 3/4" 4140 axle
Use 1/8 steel cable instead of 3/32 for sling cable (2000 lb vs 900 lb breaking strength)
Replace rail track
Could be done for ~$300
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How did we end up with the initial budget? Maybe we can scrape together a little more cash to repair and ready it for next year.
I’d like to enter the 2x4 trebuchet, Peggy jnr, next year also. It was firing with amazingly accuracy
We spent about $2,200 during the build (1500 from original allocation through PR, some from Auto, rest from donations)
We gave away Peggy jnr at the end of the competition to avoid having to haul it back
I’m up for getting her fixed. So sad I missed the event.
So is the angle track broke? Just looked up 1-1/2" angle, 3/16 is 1.50 a ft & 1/4 is about 2$ a foot. Maybe we could use split DOM as track which should be stronger than angle.
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The track deforming / flattening hopefully saved the weight axle and frame from bending, in rush to pack / unload I didn’t take any pictures of damage.
It only deformed after the arm breaking, after breaking the pivot wheels left the track and the lower arm assembly to jumped forward (rotating about the weight axle), with the weight still travelling down all that force flattened part of the rail and busted the cast wheel. If you watch the video will see that the entire 2,000+ pounds jumped up in the air some during the pivot wheel breaking / rail flattening. Making rail stronger would be possible but may not be necessary, will need to see what kind of force it takes to flatten angle iron in that orientation.