Tubing plugs

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Titan
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Tubing plugs

Post by Titan » Tue Jul 13, 2010 7:49 pm

so I was at the hardware store today at lunch to buy the final pieces for my CPH and came across these, thought I should share this with the group

I'm not sure if this is the exact brand but it should give you an idea of what I'm talking about
http://www.mocap.com/tube-plugs-round-standard.html

I found one that fits perfectly onto a 3/8" aluminum rod and also fits snugly inside 1/2" PVC

all I have to do is trim the "Cap/button" portion off and glue it onto my pump rod, this should eliminate the issues I have been having with o-rings not sealing properly

I'll let you know how it works out :D

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cantab
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Re: Tubing plugs

Post by cantab » Tue Jul 13, 2010 9:25 pm

Those caps aren't meant to seal against pressure, so I don't know how well they'll work. But not much you can do besides try it and see.
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zeda.beta
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Re: Tubing plugs

Post by zeda.beta » Wed Jul 14, 2010 1:00 am

They'll probably blow out, as cantab said, because they don't grip the pipe.

I would get real end caps, made from copper, and then do whatever you're supposed to do to connect those properly.
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C-A_99
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Re: Tubing plugs

Post by C-A_99 » Wed Jul 14, 2010 3:04 am

I usually use a tiny cut of a 3/8" wooden dowel to stuff into the end of a 1/2" aluminum rod, then cover it with epoxy/epoxy putty. It has worked every time so far.

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cantab
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Re: Tubing plugs

Post by cantab » Wed Jul 14, 2010 4:21 pm

zeda.beta wrote:They'll probably blow out, as cantab said, because they don't grip the pipe.
It won't blow out, because it's going on the inside end of the pump rod - so the pressure would force it against the rod. The idea I think is that the ridges will seal against the inside of the pump cylinder, like a o-ring does.
I work on Windows. My toolbox is Linux.
Arsenal:
Super Soaker: XP215, 2xXP220, Liquidator, Aquashock Secret Strike M(odded), Arctic Blast M, CPS1200, CPS2100, SC Power Pak, 3l aquapack, 1.5l aquapack
Water Warriors: Jet, Sting Ray M, Shark, Argon M, Tiger Shark, PulseMaster
Others: Waterbolt, The Blaster, Storm 500, Shield Blaster 2000, generic PR gun, generic backpack piston pumper (broken), 3l garden sprayer M, 10l water carrier:

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zeda.beta
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Re: Tubing plugs

Post by zeda.beta » Wed Jul 14, 2010 5:46 pm

Oh, didn't quite get where they were going to be used. They might work, but o-rings could offer a better seal when combined with that.
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Silence
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Re: Tubing plugs

Post by Silence » Wed Jul 14, 2010 11:18 pm

Titan, those pieces, look cool, but I'd be worried about sizing. Are you sure that the rim's diameter is larger than the diameter of whatever rod it screws into? Unlike an O-ring, there may not be too much leeway because there may be too much material for it to be able to compress.

Regardless, I agree that strength shouldn't be much of a problem. Some type of plug, secured by epoxy, should do the trick.

zeda.beta, initially I thought the pieces were meant to be used for nozzles, too. Unfortunately, there's not much to hold onto when screwing and unscrewing them, which could be problematic when they're wet.

Titan
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Re: Tubing plugs

Post by Titan » Fri Jul 16, 2010 2:09 pm

I got to test this a bit last night

these plugs are made to be pressure fit into tubing so they are always slightly larger than the tubing they are made for, so the one I have is made for 1/2" metal tubing, I'm guessing somewhere in the 16ga wall thickness area, the "fins" are larger than 5/8" and fit quite snug inside 1/2" PVC

the plugs also do not "screw" in or out, each "fin" forms a complete circle around the center of the plug

the issue that might be a dealbreaker is that even tho it seals very well, I don't think there is any amount of lubricant in the world that this thing won't scrape off the walls of the pump tube, so it gets stuck and eventually pulls off the shaft

gorilla glue and other superglues may not be good enough, (I'm waiting for a full 24 hour cure to test again) I might have to go with a 2 part epoxy

if this doesn't work, the other end of the 3/8" rod I'm working with has my other solution, press fit nylon bushings with a 1/8" thick o-ring sandwiched between them
Last edited by Titan on Fri Jul 16, 2010 2:17 pm, edited 1 time in total.

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zeda.beta
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Re: Tubing plugs

Post by zeda.beta » Fri Jul 16, 2010 5:44 pm

Use 2 part epoxy, and then sand the edges of it to fit your pump with the best seal, but not too tightly.
I reject your reality and substitute my own.
Quack damn you.

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