Overflow box hairline crack sealing

[All_talk]

Can you contact the manufacture about the plastic type? I suspect its not acrylic, but more likely something like ABS or vinyl (PVC). Weld-on should still work in tis case, and would be better than superglue. I would start with the thin stuff wicked in from the backside, that will minimize the appearance from the front.

If there is a structural or ageing issue causing the cracks, the fix will only be temporary without reinforcing or other measures. Or were the cracks caused by impact?

 

[cec009]

I would first try a thin bodied Weldon product. I've never fixed an overflow, but I've built a small sump before and the capillary action will pull the Weldon into the open space as long as it's not too large.

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Do you think I could do it with thicker weld on like 16? Im concerned weldon 4 may be too thin and run down the veritical walls of the box.

 

[cec009]

Can you contact the manufacture about the plastic type? I suspect its not acrylic, but more likely something like ABS or vinyl (PVC). Weld-on should still work in tis case, and would be better than superglue. I would start with the thin stuff wicked in from the backside, that will minimize the appearance from the front.

If there is a structural or ageing issue causing the cracks, the fix will only be temporary without reinforcing or other measures. Or were the cracks caused by impact?

They were caused by impact

 

[cec009]

They were caused by impact

Unfortunately the manufactuerer (CAD LIGHTS) seem to be no longer operating.

 

[RealFish]

Do you think I could do it with thicker weld on like 16? Im concerned weldon 4 may be too thin and run down the veritical walls of the box.

Yes, but I think the thicker you go the more messy it will look. The stuff is a solvent, so you can't really wipe off the excess.

 

[All_talk]

The thick stuff will be fine, but it wont get down in the crack very well so you will want to put it on a bit like calking from the backside. For either Weld-On type I would position the tank on its front so I could apply the glue from the back side with gravity pulling it into the crack. This position will also keep it from running down the overflow. If the crack is open enough for the glue the drip through put a rag under it to keep it off the backside of the front glass. If glue drops dry hanging off the front face of the overflow, a little work with some sand paper or razor blade should scrape them off. Its never going to look prefect but if you minimize work from the front side it should be to bad.

 

[cec009]

The thick stuff will be fine, but it wont get down in the crack very well so you will want to put it on a bit like calking from the backside. For either Weld-On type I would position the tank on its front so I could apply the glue from the back side with gravity pulling it into the crack. This position will also keep it from running down the overflow. If the crack is open enough for the glue the drip through put a rag under it to keep it off the backside of the front glass. If glue drops dry hanging off the front face of the overflow, a little work with some sand paper or razor blade should scrape them off. Its never going to look prefect but if you minimize work from the front side it should be to bad.

I was under the impression that weldon dries crystal clear and therefore would not appear on the overflow box?

I have 3 glass panels inside the box that is siliconed to each of the 3 sides of the box. It came like this form the manufactuer I think maybe it's to add rigidity to the box. I would have to remove the box from the display tank and remove the glass panels from the box in order to access the back of the box. It's doable but just a bit of a hassle...

 

[All_talk]

Sounds like you are going to have to work from the front. In that case I would lay the tank on its back to avoid drips down the overflow and try my best to make clean little glue beads. Weld-On does dry clear, but you are still going to see it, especially the thick stuff.