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Forgive please, dump valves for air bags source?
Posted: Mon Dec 29, 2008 2:11 am
by bambam
Seems like one for the FAQ section, ..., I did look around a bit but couldn't find a source.
I'm talking about the bigger thinga-ma-bobs on air bags which we use to let the air out / inflate with electric pumps, not the small valves on tubes we use to top them off.
They get old, crack, the tabs you pull on to open them break off, ... , while the flotation remains quite solid.
Anyone have a source?
Thanks,
Ken
No say
Posted: Mon Dec 29, 2008 12:39 pm
by Louie
What I would do is Aquaseal the whole thing shut and just use the small tube
Posted: Mon Dec 29, 2008 6:02 pm
by oc1paddlr
i agree with louie....once i watched mr. deadlegs surfing nantahala falls when the water pressure blew open the dump valve. soon he was surfing AND part of the falls. one guy in the eddy said "i've never seen a canoe get in there like that!"
Posted: Mon Dec 29, 2008 7:03 pm
by sbroam
I like the valves in the Pyrahna bags - if they blow out, you've got other problems. They are a beefy screw type valve that I am sure is used in something else, maybe rafts or something industrial. Anybody know anything about those?
Re: No say
Posted: Mon Dec 29, 2008 11:36 pm
by bambam
Louie wrote:What I would do is Aquaseal the whole thing shut and just use the small tube
Already did that (but with Plumbers Goop, I think).
The trouble is it takes forever to deflate / inflate the bag.
Ken
Posted: Tue Dec 30, 2008 1:02 am
by sbroam
I think the elbow, length of tubing, and twist
float bag valve are a weak point - especially the elbow. I'm inclined to use Goop to see
that off if I could replace the dump valve with something better (like the valve on the Pyranha bags). I'm wondering if one of the valves here would do it :
http://nrsweb.resultspage.com/boating/Valves
Posted: Tue Dec 30, 2008 3:05 am
by oc1paddlr
i agree also with you scott on the tubing stuff being the weakest link. the valve can easily be replaced, often for free by the good folks who made the air bag. weakest point- that elbow glued into the bag needs a tube long enough to secure it to or under the lashing of the air bag so it does not flop around while on the road. nothing wears that seal out faster. also, bags need enough air so's not to flop around too. iorny, the dump valve gives access to repair the tube valve , don't ja jus luv it!!
Posted: Tue Dec 30, 2008 3:17 pm
by sbroam
On one set of bags I have there are grommets at the corners but also one in the middle (at the seam on the wide end) - through this I put a short loop of small diameter shock cord and a cord lock to secure the valve end of the fill tube. That has minimized the flopping around and yet I still recently found that the elbow has signs it is about to start cracking. I put a couple of layers of Goop on it. Grrr. I have another older set of bags that are still air tight except for bad fittings - the elbows and dump valves...
Yeah, both of the valves tend to be problems, for me anyway.
Posted: Tue Dec 30, 2008 9:04 pm
by ChrisKelly
I take my bags out of the boat for any kind of long trip but realize that many people do not.
My friend Oc1 Kanubi sez he treats his air bags like British children in the coal mines. Once they go in they don't come out till they die.
Posted: Tue Dec 30, 2008 9:53 pm
by c1swim
I have some new air valves for my old Ryken "Chief" WW raft (14ft).
Perhaps something like that would work. I have yet to get around to replacing them (8-9years) I will try to find them and see.
I know valves are available for rafts; just don't know if they would work. You might try googling "air valves".
Roberts Valves
Posted: Wed Dec 31, 2008 12:03 am
by Don Beyer
We used to get our float bags made by a waterbed mfgr. and they used those valves. I think those were heat sealed in. I think I lost their address when I got rid of my 8-tracks, though.
Anyway, try Roberts:
http://www.halkey-roberts.com/moreinfo.asp?pic=1&ID=398
Don
Posted: Wed Dec 31, 2008 2:36 pm
by bambam
Hi Don.
Thanks for the tip. I'll give them a try.
Ken
Posted: Wed Dec 31, 2008 5:20 pm
by oopsiflipped
I don't know how you'd attach them, but the 'river tube' valve is what is often referred to as a boston valve and is the most similar valve to those on the pyranha bags.
I had one pyranha bag that i thought was great and the other leaked quite a bit. I might have poked a whole in it though. One draw back to the pyranha valve is that if you are as dumb as me you can drop the cap in the crick. i only did that once and somehow i found it.
Posted: Wed Dec 31, 2008 7:45 pm
by Marc Evans
Bambam:
I'm in agreement with Louie - Aquaseal the thing shut and use the small tube. I leave my bags in my boats and do a partial deflation when traveling. We typically have a 2,000 foot change in elevation to get to water, so I deflate the bags enough to compensate for the elevation change. Never had a problem, but have seen some twisted gunwales on another boat.
Scott and Gabe are right about the valves. You could probably replace the current dump valves with the NRS valves described. Though I'd check for glue compatibility, if gluing is required.
As for the small inflator tube, I'm with Scott. The elbow and connection to the bag are an area of concern. After getting several sets of NRS infinity (urethane) bags cheap I found the elbow and connection to be weak (the bags are strong, but the connection is weak - probably why they don't sell them for canoes anymore). Three or four layers of Aquaseal on the connection and over the elbow will do the trick.
Gabe - your pyranha bag did have a leak, but not anymore. Aquaseal - the fix all. I must admit I do worry about losing the cap off the pyranha bags. Up the crick without floatation, that would be a bummer, especially the way I boat!
Marc
Posted: Sun Jan 11, 2009 3:19 am
by Mike W.
I don't know why I didn't think of this sooner. I was replacing some leaky water bags today & thought of this thread. The water bags that are used to hold down inground swimming pool winter covers have a valve that is nearly the same as you find on canoe air bags. The difference is the water bags do not have the little flap on the inside of the valve. Otherwise they look the same. You can get a double chamber bag which will have 2 valves for $5.49. I'll bet you can heat the glue & it will release so you can put it on your air bag.
http://www.waterwarehouse.com/poolsuppl ... 9959p.html