Bowed top on DIY stand

Bruce Burnett · Jul 3, 2017

I would suggest what has already been posted and that would be shim a sheet of plywood on top and set the tank on the leveled out plywood. Don't ever use foam to fix level problems. Also make sure you are flat end to end, front to back and diagonal corner to corner a twist can be worse than a little bow. Much nicer looking than my stand.

Robert Vacchiano · Jul 3, 2017

I am a carpenter and have made stands before the gap looks to big if you can not get it down I would put another piece on top of it and shim level and then put a piece of trim to hide the fix .Putting the tank on the bow would not be good

Robert Vacchiano · Jul 3, 2017

Stand looks great just fix top

clsanchez77 · Jul 3, 2017

There are some good recommendations and not so good ones in here. Do not use foam, despite what others say and what manufacturers say. Just don't.

I agree with sanding it down level and then putting a new board on top..then re-trim it out. That is what I would do.

Here is the cabinet I built:

Right Doors Hung by Christopher Sanchez, on Flickr

It is constructed of 3/4" birch plywood for the base structure and then skinned in 3/4" cherry. After I had the base and side cabinets done, I noticed the empty tank, which came late, did not sit flush and I also had a high spot center front and right rear. I ended up sanding all down on a belt sander with 80 grit, rebuilding the profile with wood puddy and got the front and back rails solid and level. I do not have the top panel like you do and it is not required for rimmed glass tanks. I prefer to see the underside of the sandbed from underneath. Personal preference.

It is fixable but will require work. In the end, it will be worth it!

Beautiful work by the way!!!

Fritzhamer · Jul 3, 2017

A frown is good, a smile would be bad. Ten years ago I had an AGA stand to go with my AGA reef ready tank. I had it on the stand dry and noticed about a half inch gap between the corner on each side and the stand. I freaked and called AGA.

They had me send a photo with a ruler next to it and replied: "that gap is fine, it will settle and even out when you fill the tank with water."

They were right and it did. When building things that will bare weight you always place the bow facing with the highest part in the center. All wood will have a bow to it. When weight is applied it will push the bow straight.

If a bow is totally unacceptable to you do what the pros do. If you want a 2x6, start with a larger piece of stock and cut it long ways and wide ways on a table saw to get it true. Then use a planer until its 2x6 (1 3/4 x 5 3/4). This is totally unnecessary though.

clsanchez77 · Jul 3, 2017

Fritzhamer said:
A frown is good, a smile would be bad. Ten years ago I had an AGA stand to go with my AGA reef ready tank. I had it on the stand dry and noticed about a half inch gap between the corner on each side and the stand. I freaked and called AGA.

They had me send a photo with a ruler next to it and replied: "that gap is fine, it will settle and even out when you fill the tank with water."

They were right and it did. When building things that will bare weight you always place the bow facing with the highest part in the center. All wood will have a bow to it. When weight is applied it will push the bow straight.

If a bow is totally unacceptable to you do what the pros do. If you want a 2x6, start with a larger piece of stock and cut it long ways and wide ways on a table saw to get it true. Then use a planer until its 2x6 (1 3/4 x 5 3/4). This is totally unnecessary though.

Considering many manufacturer stands do not even support the front or back rim of glass tanks, I would not totally dismiss a smile either. I think supporting the corners is most important and you are right, the weights we are dealing with, things settle. I prefer not to depend on that however

Making sure the stand is and remains level is the most important thing...and the issue you run into is if the stand has to settle to accommodate the tank, you may have lost level. It's a give and take for sure, but it needs to be good enough so your not losing sleep over it. Personally, I would just fix it...for the comfort level if nothing else.

merfish101 · Jul 4, 2017

Going to try sanding some more to see if I can get rid of the bow or at least bring it down some more. Either way, I'll be adding another top and shimming. Put a lot of time and effort into this project and I need to be able to sleep comfortably when it's done.
THANK YOU GUYS FOR ALL YOUR HELP. It's just one of the reasons I like R2R and this Hobby.

Paul B · Jul 4, 2017

The stand is beautiful, nice work. Unfortunately, and I hate to say this but the design is flawed. That overhang, and I can't tell how big it is will sag no matter what you do because 3/4" plywood is not meant to carry any weight in an overhang like that. The corners of the tank, especially a tank of that size, really need the weight to be carried straight to the floor. It will support the tank as it is but the silicone on the front and the rear glass will be stressed and after a while, leak. Sorry, but that is my opinion. I have built many stands for tanks, generators, air conditioners and entire buildings.

airmanv05 · Jul 4, 2017

From what i am hearing (and can see), the likely culprit is the cupping top that is in place. Did you make the top by altering the cupping of each board used for the top or is it a single ply panel? If you used real wood and didn't sequence the boards, natural cupping in the wood can cause pronounced crowns in the top if not alternated during glue-up. By alternating the convex and concave orientation of each board used for the top, you straighten the effect of cupped boards. Wood selection avoids this. Also jointing and planing each part of your top eliminated largely this defect of natural woods. Look at the end of the top for this. Do you see a crowning in the end of the stand top ie; a crest in the middle with the corners at the low point? this would explain everything. Solution: replace top with a plywood product and apply an edge band veneer that irons on and can be trimmed to appear like a natural wood top. A rather inexpensive and time sensitive solution. Good luck sir... rest of it looks great.

clsanchez77 · Jul 4, 2017

Paul B said:
The stand is beautiful, nice work. Unfortunately, and I hate to say this but the design is flawed. That overhang, and I can't tell how big it is will sag no matter what you do because 3/4" plywood is not meant to carry any weight in an overhang like that. The corners of the tank, especially a tank of that size, really need the weight to be carried straight to the floor. It will support the tank as it is but the silicone on the front and the rear glass will be stressed and after a while, leak. Sorry, but that is my opinion. I have built many stands for tanks, generators, air conditioners and entire buildings.

I was not under the impression the rim/edge of the tank would be supported around the perimeter of the top board, but rather that would be skirting around the bottom of the tank. Biased by previous examples I suppose. But if that top is cut to the same dimensions and the tank and the edges of the tank are unsupported, than Paul is absolutely correct. Glass rimmed tanks must be supported adequately at the rim, especially the corners.

Paul B · Jul 4, 2017

It is not clear to me if that is the case. He didn't state, I don't think if the tank will go all the way to the edges of the plywood.

merfish101 · Jul 4, 2017

The top is larger (5" overhang) on the sides and the front. The stand is built to the dimensions of the tank. The top is a sheet of 3/4" Baltic birch plywood. It sits on (glued to) a 1/2" sheet of birch which is also the dimensions of the stand and tank.