How to mold dart tails out of a milk container.

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boyntonstu
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Mon Nov 02, 2009 8:56 pm

http://www.airgununiverse.net/community ... 132.0.html

Very nice description and photos.

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boyntonstu
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Thu Nov 05, 2009 7:32 pm

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I used a heat gun to melt the container clear.

I plan to hot glue a disk of closed cell foam at the end of the tail to add support and to be a piston in the barrel.

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theBOOM
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Thu Nov 05, 2009 9:28 pm

I believe there is another how-to on this same thing.. too lazy to find it though :lol:
But I have tried... it works pretty well but its a PITA to get burned by the melting plastic.
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boyntonstu
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Fri Nov 06, 2009 8:35 am

theBOOM wrote:I believe there is another how-to on this same thing.. too lazy to find it though :lol:
But I have tried... it works pretty well but its a PITA to get burned by the melting plastic.

i hold the plumb bob at its top and my fingers are not near the hot softened plastic.
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spudtyrrant
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Fri Nov 06, 2009 9:56 am

fun fact you can make pistons using this also UHMW ftw, just be sure to grease your mold VERY well
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john bunsenburner
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Fri Nov 06, 2009 1:22 pm

Hmm, if you used thicker sheets of plastic, and made the end of the brass thing blunter you could do a better job of it. Also what does he make his shafts from?

I see the heads getting in the way of mass production unless you make a die for it. Perhaps commercial arrow heads are a better alternative?

Overall sounds like a great way to make darts, especially many and uniform ones. If you had the facilities you should machine a ring at the bottom of the brass die so that the plastic forms a bit of the lip, this would be of structural benefit.
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Fri Nov 06, 2009 2:50 pm

This has been posted before, though it is always good to be reminded of handy techniques. (http://www.spudfiles.com/forums/small-b ... t6589.html)

You would get much better shapes if you did it as a vacuum form instead of just pushing the mold into the hot plastic. I've seen very simple vacuum formers built from a plastic peanut butter jar. It was used to mold nose cones (or darts?) using a conical shaped Lego piece as the form.

A shop vac (or house vac) provides sufficient vacuum and flow for small pieces.

Come to think of it, all you heed is a piece of wood larger than the vac's hose end. Drill a single smallish (1/8"?) hole in the center of the wood. Set the mold on top of the hole and set the entire thing on the end of the vac hose. You might need to use something like toothpicks to lift the mold slightly off the platen.

A little more work would be to drill a grid of smaller holes that cover the entire platform. You then wouldn't need the toothpicks to hold the mold off the platten.

My son has a large (2'x2') home brew vacuum former. It's really simple.
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