Shimming?

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krap101

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Roscoe, IL
I built the skeleton of a 29 gallon stand today, and I noticed it doesn't sit totally flat, so I guess I need to shim it? I see the shims at menards or homedepot, but I was wondering what to do with them? Do I just keep pushing them in until they're level? Should I nail them on afterwards?
 
I built the skeleton of a 29 gallon stand today, and I noticed it doesn't sit totally flat
Is the stand plumb, level, and square? Is the height inconsistent, or is the floor where the stand sits not level? Also picture of the stand in place would help.

Do I just keep pushing them in until they're level?
Depends on what's not level. Also, what kind of surface the stand sits on. Would leveling feet on the stand be better?

Should I nail them on afterwords?
Not if your leveling at the floor. Floors tend to need re-adjustment over time. If the stands not plumb, level, or square, that's different.
 
I think one of the legs is a bit short, and if I push it over, it wobbles. The other three legs are fine, and is pretty level.

I'm not totally sure what plumb means, but I'm assuming it means something relating to plumb-lines.. meaning vertical? I'll go take a picture.
 






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The stand isn't finished yet, but I wanted to figure out how to fix this before the time comes. I built it in the heater room in my basement (since its winter) and can't be 100% sure the ground there is totally flat.
 
I think one of the legs is a bit short, and if I push it over, it wobbles. The other three legs are fine, and is pretty level.

I'm not totally sure what plumb means, but I'm assuming it means something relating to plumb-lines.. meaning vertical? I'll go take a picture.

Plumb means all 4 legs are perfectly vertical. You need to measure this when you place the stand on a spot that is perfectly level.

What do you mean - "it wobbles"? Is the stand wobbly? If yes, you have some fixing to do. If the frame is rigid, and the whole thing wobbles on the floor, you need to find out why.

First, measure the floor with a long level. If it is not, find a spot that is to test the stand on. In a pinch, put it on a piece of plywood & shim the plywood until you have a level surface.

Next, measure to see if the stand is plumb - ie vertical is all directions - check each leg in both axis.

Then, check that all your corners (all 24 or them!) are square. <Alternative - measure the 2 diagonals on all 6 faces. The diagonals on each face (& its mate opposite) should be within 1/8". (It should ideally be identical.) >

If any of the measurements are off, you need to correct the stand. I assume that you glued your joints. That will make correction difficult. If the stand is off by just a little - say 1/4" or less - you can belt sand it until the bottom is perfectly level (& the legs are plumb) so it won't wobble. Then belt sand the top so that is level with your floor. Anything more & you need major surgery.

Let us know how far off you are & we can give you more directions. In general, it is best to have your frame perfect & shim the floor where it sits if the floor is not level. It is bad practice to shim up an off plumb/ out of square frame, esp. when you have a lot of weight on it. The shimming puts your legs out of plumb & put stress on the joints.
 
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You need a level to start. A level has glass tubes with a liquid and a air bubble in it. It will tell you when the stand is level even if the floor isn't.

Start at the lowest corner using shims to raise the corner until it's level from side to side. Then check front to back and level accordingly. Then recheck side to side if it's level both ways your good to start filling your tank. If not then speak a few choice words and start over. Experience has taught me to fill the tank a few inches and check again. Check at half full too. I also recommend a plywood top on the stand the same size as the tank. Good luck.
 
One other thing - make sure you try it in different locations. Concrete floors are never perfectly flat. Whatever you do to level it, do it in the exact spot the tank will be kept.
 
Ideally you would want the wood taking the load, not the screws. Being a 29g I wouldn't worry too much. You can see what I mean by looking at my stand build thread:

http://www.aquariumadvice.com/forums/f20/30g-long-and-10g-stand-102727.html

The top frame rests on the 4 (8 since each corner has two 2x4s) legs and the legs rest on the bottom frame, distributing the weight.

When buying the shims make sure to get a hardwood.
 
If the stand "rocks", then you need to adjust something or shim. But if it wobbles (i.e. the top moves relative to the bottom) then you need some some sort of diagonal bracing.
 
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