900 gallon plywood shark tank build
- Thread starter dingodan
- Start date
I precut my cloth and used nails to pin it to the top of the tank so it wouldnt sag. Then flipped it up, rolled a coat of epoxy over the wood, then flipped the glass down and rolled or brushed another coat of epoxy over the cloth (i used the brush until i finally discovered at the end the roller gets a way more even coat) . I then rolled it out with an alluminum fin roller. I didnt have much issue with air bubbles but when i did i used a heat gun while the epoxy was wet to get them out. Im not over concerned about the small amount of air bubbles i currently have as ive heard fiberglass isnt completely waterproof anyways. On my next few top coats ill pay extra attention to bubbles. I was honestly scared ****less about fiberglassing but it went very well for me. Use epoxy with an hour working time, use cloth not mat, pre cut your pieces. Buy proper rollers and take your time mixing the resin.
Did my first topcoat last night and i would agree its near impossible to not get thousands of tiny surface bubbles. I found lightly brushing it after rolling it on did help alot. Im assuming that after several coats with light sanding between each coat this wont be an issue but i really dont know
Its just how it was done in the plans i was following. Apparently it prevents the corners from being able to blow out which is ussually a weak spot. Doubt id do it that way again but its done now and itll help me sleep at night
yeah 900 gal of water on the floor is no joke. better be safe than sorry!
if you where to do it again how would you do it now?
Well i think i would just do a 3/4 plywood skeleton no 2x4 and fiberglassed the **** out of it inside and outside. In my experience the fiberglass was pretty easy and im sensitized to epoxy. Meaning i cannot get it on my skin AT ALL. Theres too many unknowns with the different expansion rates of wood and epoxy. So just build it like a high quality boat and i think thats the safest method. I am happy with the way i did it, but it was very time consuming so that being said i think one might as well go full fiberglass.
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Was thinking of doing something like yours but slightly taller (62x31x40 inches). What thickness of plywood would you recommend so it does not bow (with a euro brace). In my case both of the larger sides will be mostly viewing panels. I thought of going full fibre but could not find the recommended thickness for my dimensions. What would you say would be an acceptable thickness? As for the fibre to avoid the bubbles it helps to first "soak" the plywood well (normally 2 to 3 coats of resin will do) otherwise you will have the air trapped between the fibre and the newly applied resin on top and the air will have to "fight" it way through the resin, which is why is ends up trapped. I found the best way is to soak the plywood, and when tacky apply the cloth with generous amounts of polyester resin with a normal roller and then press with an aluminium roller to remove the bubbles. Usually the finished product comes quite good. It is crucial but to always the next layer when tacky, otherwise, if it sets, you will have a cold joint. You can sand and apply again, but its not quite the same in terms of strength, as you will have multiple layers rather than one thick layer. You have to play with the hardener ratio to manipulate the setting times to get this, unless you plan to build it in shifts with someone else
Ups has been "holding" my sweetwater epoxy for almost a month. Cant progress on the tank until i get it but heres the begining of my mechanical room/wall to keep me busy. The bottom pipes are the supply to my pumps and the top pipe installed is the output from my skimmer. More to come...
Yea i sanded between each coat. I would have had to take a week off work and sleep to have 1 continuous layer of epoxy. I cannot give you any recommendation as to plywood thickness as this is my first time doing this and am no expert. I would guess 3/4 to 1" for that depth but try looking for other builds with similar depth to yours. You can also look into fiberglass plywood hot tubs for some ideasWas thinking of doing something like yours but slightly taller (62x31x40 inches). What thickness of plywood would you recommend so it does not bow (with a euro brace). In my case both of the larger sides will be mostly viewing panels. I thought of going full fibre but could not find the recommended thickness for my dimensions. What would you say would be an acceptable thickness? As for the fibre to avoid the bubbles it helps to first "soak" the plywood well (normally 2 to 3 coats of resin will do) otherwise you will have the air trapped between the fibre and the newly applied resin on top and the air will have to "fight" it way through the resin, which is why is ends up trapped. I found the best way is to soak the plywood, and when tacky apply the cloth with generous amounts of polyester resin with a normal roller and then press with an aluminium roller to remove the bubbles. Usually the finished product comes quite good. It is crucial but to always the next layer when tacky, otherwise, if it sets, you will have a cold joint. You can sand and apply again, but its not quite the same in terms of strength, as you will have multiple layers rather than one thick layer. You have to play with the hardener ratio to manipulate the setting times to get this, unless you plan to build it in shifts with someone else
