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While I was doing my seaworthiness inspection, prior to beginning the return voyage from Bermuda, I discovered my starboard water tank vent hose fitting had split. It is split at the base of the fitting where it attaches to the tank. From the little bit of research I've done I'm led to believe the tank is constructed of HDPE plastic. I have discovered it can be welded with a heat gun if you have a piece of HDPE to act as the welding rod.
Has anyone tried this? Do you have a HDPE source? Does anyone have another solution? Does anyone have a solution which does not include a replacement tank
I'm not going to tear it out until I have a viable solution since it doesn't leak if it's half full and is therefore usable in its present state. I must get it repaired or replaced though because things like this drive me nuts. Ignoring it long term is not an option.
Not sure how this applies to tanks, but with HDPE pipe the joints look like a weld but are actually formed by heating both pipe ends and squeezing them together with significant amounts of pressure. There is no donor material involved like a true weld. This all done by some pretty hefty machinery, although my experience is limited to large diameter/heavy wall piping.
In the field they refer to this as fusing or a fusion weld, may help to look up these terms. Hope this helps lead you in right direction.
Steve
Pleasant Journey, Morgan 35
Previously:
'85 CD 26, Hull No. 30
'74 Typhoon Hull No. 789
Great Bay/Little Egg Harbor, NJ
This is more what I had in mind. I'm just trying not to reinvent the wheel if someone has solved a similar issue already. If it's possible to patch a kayak made of HDPE it should be possible to do the same to a water tank.
Grumble. I've had this problem too. The first time I took them to a plastic welding shop. They made plastic tanks mostly for hospitals and agreed to do my tank repair as a side job. The bill was high enough that I swore I wouldn't do that again. I think the tanks are actually polyethylene. I've had luck doing a couple additional repair jobs two different ways: the first was to shave excess material from mold lines and use that to melt into cracks (after opening them up a bit). There is of course, only so much excess material to be found on the tank so the next (third) time I had to do repairs, I purchased polyethylene tubing from Home Depot ($3.47 for 25') (http://www.homedepot.com/p/Watts-1-4-in ... /202257563) and used that as the welding rod. Either method is pretty cheap and relatively effective. This fall I discovered a new crack in the tank- I've had it with repairs and plan on ordering new tanks soon.
Worth noting, I had several cracks located at the molded fittings as well. It appears they were all due to the tank actually resting on these fittings rather than the tank bottom because the notches in the bulkheads that allow the hosing to reach the fittings were too shallow. I'm not sure I'm describing it clearly, but I suggest folks check to make sure their hose fittings are not bearing any weight. It is a simple fix that can prevent major headaches.
I've had this exact same problem on my water tank under the starboard settee. I found that using 3M Scotch-Weld DP8005 Structural Plastic Adhesive, along with a patch made from a gallon milk jug container, did the trick. However, the adhesive is not cheap, and I found it easiest to use 3M's applicator - combined, the adhesive and applicator cost about $100. But it makes for an easy repair.
I'll look into both solutions, thank you all. I have no clearance issues with my installation so I'm not sure what caused the crack to develope. in the fall I'll remove the tank and inspect it carefully to ensure there are no additional "hidden" issues and repair or replace at that time.
I repaired my tanks with J-B WaterWeld. I got it at Home Depot.
It isn't expensive, did a great job, and according to the package it
is fine for potable water.
JimMc wrote:I repaired my tanks with J-B WaterWeld. I got it at Home Depot.
It isn't expensive, did a great job, and according to the package it
is fine for potable water.
Jim.
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Thanks for posting that, had thought of J-B out in Bermuda but didn't know they had a formula compatible with potable water. I'll look into this for sure.
JimMc wrote:I repaired my tanks with J-B WaterWeld. I got it at Home Depot.
It isn't expensive, did a great job, and according to the package it
is fine for potable water.
Jim.
------------------
Thanks for posting that, had thought of J-B out in Bermuda but didn't know they had a formula compatible with potable water. I'll look into this for sure.
It isn't on the front of the packaging, it's on the back. But it's there. Love that stuff.
Use the JB Weld Plastic, not the grey stuff. Rough up the area to be repaired and heat it with a gun for a short time before applying as that is supposed to help it cure and bond with the plastic better. I have a repair that is going on 3 years now. The other thing I have seen when researching 3 years ago was to move the fittings to a new location and cut out the cracked area and add an inspection plate.
With white water kayaks, plastic welding used to be the only solution. West Systems now has G-Flex that should be just the ticket for what you want to do. It adheres to plastic and stays flexable.
Another solution is to take out both tanks, plug the leaky fitting and then swap them side to side. The ones on Raven are symmetrical with the same fittings on bot ends so this works out well.
JB Weld is great stuff but I think I would go with the G-Flex for this application. They have very specific directions for using it on plastic, Steve.
With white water kayaks, plastic welding used to be the only solution. West Systems now has G-Flex that should be just the ticket for what you want to do. It adheres to plastic and stays flexable.
Another solution is to take out both tanks, plug the leaky fitting and then swap them side to side. The ones on Raven are symmetrical with the same fittings on bot ends so this works out well.
JB Weld is great stuff but I think I would go with the G-Flex for this application. They have very specific directions for using it on plastic, Steve.
I have used the G-flex on other plastic items and boats ( polyethylene Boat IE Club Optimist Prams aka Opti Cube) and it has worked rather well , The other product ive used is called Plexus but I would research it for use on said material as its curing temp is extremely high
West actually has four specific G/flex products. I emailed them for confirmation of which specific product is best for a potable water supply.
Thanks for the tip.
I have the same problem on my starboard tank, broken supply fitting. I have been trying to think of a way to put a hose connection at the bottom of the tank and seal off the broken fitting at the top. but to get to to forward part of the tank, I will need to add an access port. Or. anyone have a ballpark price on having a stainless tank built? Either way, the tanks need to be secured. On my CD33 they are just sitting on supports under the bunk. I can imagine in a severe knockdown, that those tanks would blow through the bunk framing and drop across the main cabin.
Gluing HDPE is not easy. I had the same problem, and used plastic model airplane cement, the kind that they will only sell if you are over 18 and contains tolulene. I am not so sure about how food-safe it is, but the vent does not carry the water and most of the volatiles should evapourate after a while. That was 10+ years ago and it is still holding.
