LPR Technique: Cutting Hexagonal Parachute Using Protractor and Ruler

brockrwood

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Eight seems to give more uniform deployment and reduces oscillations, though it does weigh just a bit more. The competition crowd sometimes uses 12 lines on larger chutes (30-36"). It's also a lot easier to mark 8 positions on the rim of the canopy just by folding :)
For my sport flying the weight of those two hours extra pieces of thread is minimal. I am going to try it! Guess I have to make a circular or octagonal parachute, eh what?
 

bjphoenix

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I have only one serious comment: that parachute is... well, grass-colored. That would concern me a bit. Green seems like a non-optimal chute color.
If he has a way to scrounge up one of those blue trash bags used for recycling he could use that.
Or go to the dollar store or the party store and look for cheap plastic temporary tablecloths.

Some years ago my daughter built an Estes Firebird and painted it green with a purple nose cone. I had the same idea about it being hard to find in the grass, and I happened to find a can of pink paint in my garage so now it is really easy to find in the grass.
 

brockrwood

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Little rectangles of plastic packaging tape. :).
View attachment 517811

View attachment 517812

Who was it who suggested using the little, vinyl reinforcement rings instead of my trusty pieces of plastic packaging tape to reinforce the shroud line attachment points on plastic parachutes?

Whoever you are, I got some of the vinyl reinforcement rings. We are going to make two parachutes and do a head to head test!

:)


7C1BB206-9661-4F14-BBD7-AAD783E80C7D.jpeg

For the record, these are the white, plastic, vinyl-type reinforcement rings (Avery item number 5729) not the paper kind of reinforcement rings. The paper kind seem quite fragile to me.
 

neil_w

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Who was it who suggested using the little, vinyl reinforcement rings instead of my trusty pieces of plastic packaging tape to reinforce the shroud line attachment points on plastic parachutes?

Whoever you are, I got some of the vinyl reinforcement rings. We are going to make two parachutes and do a head to head test!

:)


View attachment 529852

For the record, these are the white, plastic, vinyl-type reinforcement rings (Avery item number 5729) not the paper kind of reinforcement rings. The paper kind seem quite fragile to me.
It was probably me, and you got the right kind. The paper kind are not suitable for this purpose.
 

lakeroadster

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One thing to keep in mind is that there is a limit to the strength of the shroud line / chute attachment, that's true for every parachute unless the shroud lines go all the way over the chute, what I call an "Over The Top Parachute".

So, depending on the weight of the rocket and the speed at the time the chute is deployed, it is possible for the shroud lines to be ripped right out of the chute.

I had that happen previously this year. It's a bummer when you see the chute blossom and then "poof" there the chute goes.. fluttering down to earth, not attached to the rocket anymore.

What would be way cool is if the simulation program would look at this, and flag whenever the chute material being used is "questionable" for the given application.

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