DIY Stand Construction Myths and Fears (1 Viewer)

[jlanger]

The question below was posted in a current build thread (and probably in many others), but I didn't want to derail the OP thread so I will discuss the topic here.

You sure that stand is strong enough?

This hobby, as a whole, has an undeserved fear of aquariums crashing to the floor. This is due to
a couple of factors based on the builder's experience.

The concensus is that an aquarium stand needs to be built from 2x construction grade lumber. False.
There a couple of reasons that people decide to use 2x lumber when building anything; availablility and price. Pine lumber can be found at every single home improvement store in various widths and lengths. And pine lumber is cheap; which is great for building a stand's structure but most people will add a skin to the pine stand which just adds the to the final cost.
What many people don't realize is that most pine construction lumber is still wet; it has not dried to the moisture levels that other hardwood boards are required to be. The problem with wet lumber is that as it dries, it will shrink, warp and twist. This will create new issues down the road; if not properly addressed beforehand.

Another reason that people fear a stand will not hold is from improper construction; primarily due to a lack of glue.
In any woodworking project, a good solid build is using glue. When it comes to holding wood joints together, screws act only as the clamp for the joint. The glue is what will bond the two pieces together. I tell people that if two wood joints (one with just screws and one with screws and glue) are created and then after an hour the screws are removed, which joint will still hold. The glued joint, obviously. It seems like a lot of people think just using screws to build a stand is sufficient, but it's not and this is when a stand can fail.
Everytime I give advice to DIY wood stands, I will repeat "Glue, glue, glue." It's that important.

So to overcome these fears, people will overbuild their DIY stands.
I'm not saying that these stands are not going to work, they will. What I'm saying is that overbuilt stands have created a standard that is far above what is capable of holding up an aquarium.
Have you ever taken a look inside of a mass-produced aquarium stand that the pet stores offer? I don't see any of those stands using 2x4's; let alone a quality veneer-core plywood in most cases. The "big box" aquarium stands are using 1x4 pine with composition/press board panels. Do we find it amazing or second guess that these stands will hold a filled aquarium, let alone an empty tank? No. Why not? Because they're being sold by a large corporation; so they must work. Yet we will question the quality of a stand that is built in a small shop with higher quality materials and construction standards. Why? Because it's easy to not trust a single individual versus a faceless corporation.

This post isn't about me degrading the people that build stands with construction lumber. It's more to demystify the myths and fears that a quality aquarium stand has to be built with construction lumber.
I understand that most people in this hobby are not confident with their woodworking skills and feel more confident with building a stand that will hold a couple of tons. I'm hoping that my knowledge of woodworking will help benefit those people.
I have my own short-comings and I rely on the advice of those with more experience to help me with my aquarium.

I have a response on another forum that I discuss my thoughts on the various types of DIY stand metohods that I can re-post here; if wanted.

And I welcome any and all feedback, criticism and questions.

 

[Nickz]

While I do agree most DIY stands are incredibly overbuilt, just one stupid question...

Glue, glue, glue... is this really necessary? I have built countless stands (mostly mutliple tank racks) (nothing to your level of quality) using 2x4 contruction and rabbit and/or dado joints for the crossmembers, with coated screws, never used glue. I do not overbuild my stands/racks, compared to most DIY, but a single 2x4 upright on each corner and single 2x4 for crossbeams(tanks sit on). these are built this way simply due to lack of proprer tools/time/knowledge to make them using just plywood. I usually just end up skinning them with 1/4 ply for looks when I have the extra time/$$ to do so.

 

[Bschowa]

The "big box" aquarium stands are using 1x4 pine with composition/press board. Do we find it amazing or second guess that these stands will hold a filled aquarium, let alone an empty tank?

I question them, if it shakes when my dog walks past it without water in them it makes me a little nervous to use them lol.


I agree that many people over build most things these days, not just stands, including myself.
For me I do it because I don't trust my trimming skills which building out of plywood to me basically is. So I just go with the cheep wood and knowing that it will twist/bow/warp as it continues to dry I over build it. Then I leave them un skinned until I build a new one lol

My question for you would be nails vs screws. I understand the benifits of screws that you can remove them to make transport/ building easier but is there a large sheer difference between the two? Many of us use screws to build stands and then we are essentially supporting our stand with screws ( and sometimes wood glue) I have had on many occasions been using a screw and the head snaps off but I have never had that happen with a nail. Does that mean that a nail is made of a stronger material which makes it better for building?

 

[jlanger]

Glue, glue, glue... is this really necessary?

Definitely not a dumb question.

When it comes to joining wood for a permanent bond, glue is the final answer.
Any basic wood joint (even half-laps; a good call on your builds) using only screws has the possibility of failure; I said possibility. When a glued bond is used in basic joinery and there's a failure, it's the wood itself that breaks; not the glue.
I can make a wood joint with two 2x4's using only screws and I would be able to break the joint. But I could build a wood joint using only 1x4's and glue and not be able to break the joint.

Now if you're using more advanced joinery (like your half-laps), there are more surfaces coming together to limit the direction any force can be used to break the joint. There plenty of crafty examples of wood joinery that work with no glue at all, but we rarely ever see these in an aquarium build. We pretty much are dealing with only butt joints with basic DIY stand construction.

You can get by with only screws; but screws do not create a bond.
So for those that have concerns about a DIY stand failing, I recommend using glue, glue glue above all else.

Thanks for the question!

 

[jlanger]

I agree that many people over build most things these days, not just stands, including myself.
For me I do it because I don't trust my trimming skills which building out of plywood to me basically is. So I just go with the cheep wood and knowing that it will twist/bow/warp as it continues to dry I over build it. Then I leave them un skinned until I build a new one lol

This is another reasoning for overbuilding stands; confidence in woodworking skills.
When using construction lumber, the builder knows that it doesn't need to look perfect as it will be covered with another material; which is totally validated.
But with practice, making a precision cut in a pine 2x4 is no different in making a cut in solid cherry. Measure twice. Measure again. And the cut once!

My question for you would be nails vs screws. I understand the benifits of screws that you can remove them to make transport/ building easier but is there a large sheer difference between the two? Many of us use screws to build stands and then we are essentially supporting our stand with screws ( and sometimes wood glue) I have had on many occasions been using a screw and the head snaps off but I have never had that happen with a nail. Does that mean that a nail is made of a stronger material which makes it better for building?

There is a difference between screws and nails.
It comes down to how the nail/screw is applying it's force onto the wood.
A nail for the most part is only applying a force lateral to the nail. To explain... A nail will keep boards from moving in four directions from each other (up/down and side/side).
A screw does the same but also adds the parallel direction of moving away from each piece.
Now the exception comes in the form of ring-shank nails which have tiny "rings" along the "shank" that help hold the nail in place.
When a screw is driving into the wood, each thread on the screw is creating a surface that pulls the two pieces of wood together. This driving action is pulling the two pieces of wood together, whereas a nail doesn't have any pull force associated with it.
What happens when a screw head snaps off is that the resistance from the wood is greater than the driving force. The driver wants to twist the screw beyond the limits of the material in the screw and it snaps the screw. You won't have this physical reaction when driving nails because all of the force is going with the nail into the wood.
Does that make sense? There's physics involved (pull versus push, force versus resistance, blah, blah, blah...).

Great observation and question!

 

[capman]

I have tended to overbuild aquarium stands not so much due to lack of confidence in my woodworking skills, but due my lack of confidence in my engineering knowledge. I don't have confidence in my ability to determine how strong a structure is going to be, so I overbuild so as to not take chances.

I have always used carriage bolts along with some form of cross bracing (e.g. at, say, 45 degrees or so) in my tank stands built from 2x4 lumber. Drywall or deck screws have typically been added as well, but for critical joints heavy duty carriage bolts have always struck me as being potentially more secure.

I'd love to see your stand designs in person at some point.

I agree with you though that a good glue joint is much stronger than most people realize - stronger than the wood itself. Carriage bolts and screws (and overbuilding) have always just seemed quicker and simpler to me for this sort of thing, and more easily disassembled (which was useful some years back when I needed to reduce the size of the big multi-tank tank stand/table (4' x 8' footprint) I used to have in my basement).

What sort of glue would you use for a tank stand? In my fine furniture making that I did in the past white glue or the similar "wood glue" (the yellowish stuff) was sort of standard, but such glues would not stand up to a water leak.

 

[jlanger]

I have tended to overbuild aquarium stands not so much due to lack of confidence in my woodworking skills, but due my lack of confidence in my engineering knowledge. I don't have confidence in my ability to determine how strong a structure is going to be, so I overbuild so as to not take chances.

I have always used carriage bolts along with some form of cross bracing in my tank stands. Drywall or deck screws have typically been added in places, but for critical joints carriage bolts have always struck me as being potentially more secure.

I'd love to see your stand designs in person at some point.

I agree with you though that a good glue joint is much stronger than most people realize - stronger than the wood itself. Carriage bolts and screws (and overbuilding) have always just seemed quicker and simpler to me for this sort of thing, and more easily disassembled (which was useful some years back when I needed to reduce the size of the 4' x 8' (footprint) of the big multi-tank tank stand/table I used to have in my basement).

What sort of glue would you use for a tank stand? In my fine furniture making that I did in the past white glue or the similar "wood glue" (the yellowish stuff) was sort of standard, but such glues would not stand up to a water leak.

Answer to what glue to use? Titebond III (Waterproof/Exterior Grade Glue) works great!

Being able to dismantle a stand is a consideration worth noting and using carriage bolts is a great choice.
The bolts are very strong and when used with lock washers it makes for a strong joint. And by using bolts, you can use the same holes over and over again without worry; as screw holes will degrade over repeated uses as the wood is worn each time a screw passes in and out.

If you ever have plans to be in Wisconsin, let me know and you can stop on in.

 

[Nickz]

the one thing i learned long ago was DO NOT trust the shear strength of a screw or nail (or anything that can rust) as the only thing supporting the weight, that is what led me to the rabbit and dado joints.

 

[cypho]

I have tended to overbuild aquarium stands not so much due to lack of confidence in my woodworking skills, but due my lack of confidence in my engineering knowledge. I don't have confidence in my ability to determine how strong a structure is going to be, so I overbuild so as to not take chances.

Same here. I don't know how to do the math, so I just use 5x as much material as what my gut says is surely enough.

Jason, do you do some math to work out exactly how much support is needed. If so, can you share your design process? Perhaps I should have been an engineer. I would love to learn how to do it "right". Or do you also just wing it, just with more confidence that less material will do.

 

[jlanger]

Jason, do you do some math to work out exactly how much support is needed. If so, can you share your design process? Perhaps I should have been an engineer. I would love to learn how to do it "right". Or do you also just wing it, just with more confidence that less material will do.

I used to have a link in my favorites folder, but that must have been on my old computer.

Here's a chart I just found showing the different compressive strengths of various hardwoods.
http://workshopcompanion.com/KnowHow/Design/Nature_of_Wood/3_Wood_Strength/3_Wood_Strength.htm
You can see that hardwoods have a relatively high compressive strength and stiffness.
It may seem like I'm glossing over the finer details, but I'll try to find the old link for the data I used to make my decisions on what id strong enough.

When it comes down to it, building four solid corners from the tank to the floor will distribute the weight evenly to the floor through the four corners.
My personal stands have only the corners being supported all the way to the floor. My 120gal has shown no signs of sagging or deflecting in three years and I don't expect to see any for years to come; providing my basement doesn't completely flood and ruin everything.

 

[patent]

Great thread.

The question below was posted in a current build thread (and probably in many others), but I didn't want to derail the OP thread so I will discuss the topic here.

Quote Originally Posted by anonymous View Post
You sure that stand is strong enough?

I think questions like that are pretty innocent. Most of us aren't woodworkers/engineers/etc. so we ask these questions to be educated and this thread is great for that. The ones that bug me are the know it alls who don't really know much. The "no way that stand will hold ur tank, u are about to have a 200,000 gallon mess on yur hands" type statements.

Anyway, I learned a bunch here, I've always used the cheap pine too. Thx.

 

[Fragtastic Reef]

Oh the good ol' days when I built a 125 gallon stand out of 2x2's... Not the best but it worked years ago. haha

 

[mrbill]

Nothing but screws, glue, 3/4" plywood and about 3,000 lbs.

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[RSnodgrass]

Nothing but screws, glue, 3/4" plywood and about 3,000 lbs.

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All I see is SPACE SAVINGS! 2x4's were easy to do with a chop saw is my excuse... but oh the sump space savings I'd of had if mine was built like that.

Sent from my SCH-I535 using Tapatalk

 

[mrbill]

All I see is SPACE SAVINGS! 2x4's were easy to do with a chop saw is my excuse... but oh the sump space savings I'd of had if mine was built like that.

Sent from my SCH-I535 using Tapatalk

Yep, lots of room underneath but I'm running a remote sump so its just used for storage.