Need help cnc plasma cutting trigger for trebuchet

Thanks to @TBJK for cutting out the parts, turned out great!

I didn’t notice any change in hardness, it filed and drilled easily

Tested with just the weight of the bar itself (~60 pounds) so far and it only took ~1 pound of force on the latch to release it, hopefully that will scale linearly for when there is 500 pounds on it.

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Brandon and Tim Excellent work. I’d recommend that a safety pin be installed just behind the catch so it can’t move back and release the arm until you are ready to fire. That or just above the release lever near the end. Although in the first case less force would be exerted against the catch.

Will definitely need a safety, considering that current plan is for a winch to be temporarily placed at the top spanning the uprights to winch it into place, then someone will need to get up on a ladder and remove the winch (working directly in the path of the arm if it were to prematurely fire)

IMHO it’s the triggering mechanism that is where the safety blocks accidental firing. The safety procedure starts with “Ensure Firing Pin safety is Inserted before …” some gets bumped someone gets killed or seriously maimed. Those arms are going to have tremendous shearing/thumping power.

I’m impressed with what I’ve seen so far.

Would anyone who can use the CNC Plasma be around tonight to help cut out the release pin assembly out of the same 3/16" steel plate? It’s pretty small, the arms sticking out are 1/2" wide

Pin DXF DWG (2.75" tall by 2.5" wide)
2x of the Mount DXF DWG (1" tall)

I can be up to help with the plasma if you haven’t found anyone

Thanks @PearceDunlap

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Could anyone cut 4 6" circles out of the 3/16 plate that is sitting on the small trebuchet pallet?

I will be at the space this evening for the metal shop meeting, I will cut them if nobody else gets to it first.

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They are cut out & are on the trebuchet. Wished I had alternated them to make better use of the steel though.

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Would anyone be able to CNC plasma cut 2 of the following before saturday? It’s a release pin with more static angle to increase the range we can adjust. There should be more of the 3/16 plate leaning against the forklift by small trebuchet. Should be no holes in it, just the outline

DXF
https://drive.google.com/open?id=0B1_vnCtWGO2iNFFocG1LYlpWdDA

DWG
https://drive.google.com/open?id=0B1_vnCtWGO2iaTE3b2I2bXBjaGc

I think I can swing by to do that. The current consumables may not be able to cut it. I have some that we can use.

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Done. It is on the dolly with the trebuchet.

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Looks great! Thanks for helping make a critical part for the trebuchet

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