Acrylic weld

[marcb]

I am setting up a 250 gal acrylic tank. It is about 3 years old, and the seller told me it did not leak. However, I am wondering if it might be a good idea to re-weld the seams, just to be safe.
Is this a good idea, and if so, how do I do it? I have some acrylic weld, but was wondering about application technique.
Thanks.

 

[gypsana]

I definitely would consider resealing the joints. What kind/brand of acrylic weld do you have? I would use weld on 40. They also sell a weld on 42 that comes with a dispensing gun and mixing tip. I would apply it like a bead of silicone on all joining surfaces. Also look for any crazing, that would really be a point of concern. Every time an acrylic tank is moved there are chances of a weakened seal. I hope this helps.

 

[stanlalee]

if the joints are perfectly intact you really arent doing much by rewelding the seems. all it does is dissolve and melt them back together like it already was. if there's a visable crack or it actually leaks it will bond those back together. you can inject solvent at the top of the seem and let it run down the seem (just make sure the solvent stays in the seem, dont use too much) and a minute later it will be chemically bonded and dried. I've sealed a few leaking joints that way but one was damaged in shipping (sump) and the other (an overflow box) I'm pretty sure was done poorly to begin with. if it aint broke though dont fix it. you run the risk of overrun or mistake which can lead to a cloudy area where you botched. its not like a glass seal which is just a physical bond, acrylic is basically chemically bonded into one piece

 

[stanlalee]

Originally Posted by gypsana
http:///forum/post/2868270
. I would apply it like a bead of silicone on all joining surfaces.

I dont know acrylic weld to work that way. there is thinner and thicker varieties but its not an actual seal or weld, it just melts the acrylic like acid and dries out leaving the two pieces sealed. I'm my far an expert or familiar with alot of products so I could be wrong but thats how my products work (one a liquid solvent which worked well using a syringe and one a superglue like gel which I never had good results with neat repairs)

 

[gypsana]

With the weld on 40 being a thicker product you can not get the same viscosity as a silicone but it does apply much thicker that #16 thickened(which is thicker than the regular #16.) I made my own tank and I had a certain area that was a leak issue. I used the #40 and it took care of the problem. With the other weld on products you are right, they will not do any good. The #40 I was able to build up even in the corners for precautionary reasons and it dries as hard as the acrylic it self, it is as though it is a liquid form of acrylic. Really cool stuff that not too many people know about.

 

[natclanwy]

I don't think I would try to reseal the tank, acrylic joints do not deteriate like silicone joints in a glass aquarium. Like was posted above you risk getting cloudy areas in the acrylic and you could possibly weaken the joint by trying to reseal it. I would leak test it outside or in your garage before putting in my house to make sure it doesn't leak and be sure to check for any cracks even a small crack can turn into a large one without notice.

 

[marcb]

Thanks everyone for the advice.
I have the thin liquid acrylic weld, weld-on 3. But after reading all the comments, I will do a test fill of the tank to see if it leaks first.