Polypropylene Tank Repair

CaptainForce · #1 (**permalink**) 12-10-2010

I have a crack at the top of one of my polypropylene water tanks that I have not been able to secure for years. I heard that there is a new 3M adhesive (3M 72 Spray Adhesive) that may bond to polypropylene. Does anyone have any experience with this product or any success repairing a crack in a polypropylene tank? Take care and joy, Aythya crew

brak · #2 (**permalink**) 12-10-2010

I think the "official" method of repairing polypropylene items is by welding.

LakeSuperiorGeezer · #3 (**permalink**) 12-10-2010

Un-official repair I've done is sand surface, then use silicone rubber with 3 or 4 strips of cloth about 3 inches wide, one on top of the other over the crack. This worked for many years on an RV wastewater tank and the repair outlasted the RV. I am not sure if there is anything toxic in silicone rubber.

KBuckley · #4 (**permalink**) 12-10-2010

A google search on "weld polypropylene" yields reference to a 3M product that claims to bond to polypropylene and polyethylene (DP8005). It also yields info on welding, typically with a hot air welder. Assuming you don't have handy access to a hot air welder I would try a soldering iron with a flat broad tip and practice on some scrap.

Ken

T37Chef · #5 (**permalink**) 12-10-2010

Anyone have a recommendation for a "welder" in the Maryland area? My port side water tank has a small crack, just enough to be annoying.

GaryHLucas · #6 (**permalink**) 12-10-2010

I am in NJ but we do a lot of work in Maryland and I have access to a plastic welder. Not too likely the tanks are polypropylene, most are polyethylene. Polypropylene welds much better. I just welded 2 8" and two 12" vent pipes into 4 12,000 gallon polyethylene waste water tanks in Northeast Maryland. If you are north of Baltimore or so I could probably stop by in the spring and take a crack at it. We have had so so luck with tank repairs though. Sometimes it works, sometimes it don't.

Gary H. Lucas

deniseO30 · #7 (**permalink**) 12-10-2010

every time this question comes up I give this information and no one seems to believe it works when I say it does. We used it on the poly water tank 3 yrs ago and it's still holding well. the repair was to a stress crack on the tank also.

3M Scotch-Weld DP8005 Acrylic Adhesive

brak · #8 (**permalink**) 12-10-2010

Quote:

Originally Posted by T37Chef

Anyone have a recommendation for a "welder" in the Maryland area? My port side water tank has a small crack, just enough to be annoying.

I used Maritime Plastics of Annapolis - they built a tank for me. They do welding and seem to be able to create pretty much anything out of plastic.

Not sure if they can "come to you" but they would certainly be able to do the job if you can bring a tank (or, may be, recommend someone who can do it on site).

CaptainForce · #9 (**permalink**) 12-11-2010

Quote:

Originally Posted by deniseO30

every time this question comes up I give this information and no one seems to believe it works when I say it does. We used it on the poly water tank 3 yrs ago and it's still holding well. the repair was to a stress crack on the tank also..........

With the product description and reviews for 3M DP8005 Acrylic Adhesive, I'm going to attempt it for my repair. I notice that the "mixing nozzles", "plunger" and "applicator" are sold separately for an added $70 to the cost of the adhesive. Did you find these neccessary for your patch or was cutting open the contents and mixing the total of two parts on a palate with a putty knife application suitable? I will not want to store and keep these added tools if they are not needed for a one time application. What do you think? Take care and joy, Aythya crew

DulceSuerna · #10 (**permalink**) 12-11-2010

4 weeks ago we had a massive water leak in our RV. I removed the water tank and found where the outlet hole is had been broken 3/4 of the way around. I cleaned it and used 5200. I put 4 layers (about 1 every 2 hours), into and around the crack. Ended up buildlng it up almost 3/4" I also put a few globs here and there just to check the adhesive(ness) is that a word? lol, of the 5200 and it seemed to Hold Great! filled w 40 gallons and it is still nice and dry. Not sure if your crack is due to load or? or even if the 5200 would work, Our crack was due to someone setting something on top of the outlet nozzle.