Mitred Acrylic Tank?

[stone_shot]

I've just been in contact with a guy at Bay Plastics (bayplastics.co.uk) to get a price quote on some acrylic to build my tank with. In my original query I requested router finished edges in order to get a good, clear, bubble-free (and most importantly) watertight joints but this fellow suggested 45 degree mitred edges--I was under the impression that you have to use butt joints when constructing a tank from acrylic. Will the mitred joints work as well? I'd really rather not have 560 litres of saltwater on my living room floor! :sad:
Any tank builders out there care to comment?
Thanks everyone!
chris

 

[Sploke]

I'm interested to hear the answer on this. A mitered corner would actually give more surface area between the two pieces for the glue to bond, so maybe it would be stronger than a regular butt joint? It seems the water pressure would push the same either way, so the more area you have glued the better it would be? Makes sense to me anyway, but I may be way off.

 

[aquaman325]

I'm interested to hear the answer on this. A mitered corner would actually give more surface area between the two pieces for the glue to bond, so maybe it would be stronger than a regular butt joint? It seems the water pressure would push the same either way, so the more area you have glued the better it would be? Makes sense to me anyway, but I may be way off.

I agree with you.

 

[YoFishboy]

I did a little poking around on the internet this AM when I saw this question...it seems like butt joints are the standard for rectangular/square tanks, but mitered joints are used for specialized tanks, like hex tanks....I even saw some reference made to custom museum grade tanks that are unique in their shape using mitered joints.

 

[portabuddy]

The reason for the midered edges on odd shapped tanks is like it was said above for more surface area between the two pieces, if you gave a 90 degree joint then a but joint is good because one flat edge touches the other flat edge, a midered joint is far better but not needed, it would give a better seal, but also allows more space for bubbles and leaks if done wrong, it you have a hextank then you have a 135 degree joint if you didnt mider it you would have a very small surface area between the two pieces and you would get leaks(acrylic that is), your going to use(well should) 1/2" - 3/4" thick peces and if the plastic guy is going to mider the joints for you and clean them up too then i say go for it, its stronger and the joint is going to look clearer and cleaner.

Although most hex tanks are not midered, only the expensive ones are... they are expensive because they are harder to make and last longer.

I hope this helps...

I looked into this a while back when i looked into making a 600gallon show tank in my basement... and more recently when looking into making a hex type 130gallon planted tank

 

[stone_shot]

Thanks everyone! I'm going to stick with the butt joints on this tank--but if this hobby is as infectious as everyone says, I'll be trying the mitred joints on another tank sooN!

 

[smithcreek]

Thanks everyone! I'm going to stick with the butt joints on this tank--but if this hobby is as infectious as everyone says, I'll be trying the mitred joints on another tank sooN!

Mitered joints will require a MUCH higher degree of accuracy when constructing. You will have Zero room for error. You will have to cut the pieces EXACTLY the right legth, and BOTH edges being joined must be perfect.

Structurally the butt joint is perfectly fine, you only need ONE edge perfectly cut. Then you leave an extra 1/16" on the other piece when joining and rout off the ledge when the glue dries. With that extra 1/16" ledge sticking out you also have a much better place to apply the Weld-On. With mitered acrylic you would need to apply the Weld-On from the inside, and if you drip some on the acrylic you may end up with visible defects when it dries.