Not sure why many insist on using 2x6 or 2x8's, it's not needed. Instead double up on 2x4's. Easier to work with and is actually structurally more sound. I think many overthink this.
Just my .02
Good luck with tank, sounds like a nice size.
DIY Stands Template and Calculator
- Thread starter JohnL
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Not sure why many insist on using 2x6 or 2x8's, it's not needed. Instead double up on 2x4's. Easier to work with and is actually structurally more sound. I think many overthink this.
Just my .02
Good luck with tank, sounds like a nice size.
don_chuwish
Member
I think for a tank that size I'd like professional advice. Or pay for steel. I know you're trying to minimize cost but a tank that size is just gonna be expensive no matter what.
Steel or aluminum which some swear by is not needed. Albeit, I agree in engaging with someone who professionally builds and designs cabinets for a living as to what will be the best design. I'm fortunate enough to have that in the family. Over 50 years of experience doing it day in and day out professionally - now retired. Personally, I would favor wood over steel any day unless it's a tank over 1500 gallons. This is speaking from seeing him build custom tanks furniture for over 30 years.
But, to each it's own.
Good luck!
But, to each it's own.
Good luck!
I agree with professional advice. The supplier of the tank wanted over $4k for the stand and to me that is crazy. I have not been able to find anyone locally to build the stand, so I figured I'd try myself.
RocketEngineer
Space is big.
Sure, with enough legs 2X4s would work but most of us want open access under our tanks. To span the open distance, you need wider lumber as a doubled 2X4 isn't as stiff as the larger boards.
Example: 500#s distributed across a 48" span.
One 2X4 deflects 0.134"
Two 2X4s deflect 0.067"
One 2X6 deflects 0.035"
Going to a larger board significantly increases the stiffness of that board. Doubling up doesn't help anywhere near as much as increasing the board size does for the same load case.
RocketEngineer
Space is big.
A 2X8 header is the correct side for that layout. The rest of the stand can still be 2X4 without issue.
don_chuwish
Member
So Rocket, is that data in reference to a center point load? I've always been curious how we should understand how a tank, with its distributed load across the span and self supporting nature, really loads these beams.
RocketEngineer
Space is big.
I use a distributed load and keep deflection under 1/8th of an inch. That way if the person is building the stand for an acrylic tank, the bottom gets properly supported. If they are using a framed glass tank, obviously the stand design is overkill. I would rather be safe in my suggestions than have someone's take failed because of what I suggested.
don_chuwish
Member
Ok so total estimated weight distributed around the rim? My 120g has bottom trim with a center bar so total contact point is approximately 48" + 48" + 24" + 24" + 24" x say 1" thickness for the trim?
RocketEngineer
Space is big.
Nowhere near that complicated.
The weight of the tank is 1200#s give or take which means each 48" board has 600#s evenly distributed down the length of the beam. I use a standard beam bending formula plus the known dimensions of the board and run out the equations.
The weight of the tank is 1200#s give or take which means each 48" board has 600#s evenly distributed down the length of the beam. I use a standard beam bending formula plus the known dimensions of the board and run out the equations.
don_chuwish
Member
Ah ok, so just don't worry about the amount supported at the ends. Helps with the safety factor for sure.
Ridesbikes216
New member
Haven't been through every page of this post but looking to get info on how the original design would change for a seismically active area. Live in Downtown LA and hoping to build my own stand but want to account for the possibility of lateral motion.
RocketEngineer
Space is big.
Plywood. If each face of the stand was covered in a single piece with the openings cut out, the plywood at the corners will prevent the stand from turning into a parallelogram. With all four sides thus strengthened, the stand will stay square even if something were to move.
Also, consider tanks that are as wide as they are tall or wider. A 55g is a poor choice where as a 120g is a much more stable tank. The bigger the footprint relative to the height, the better it will resist any tipping motions.
Also, consider tanks that are as wide as they are tall or wider. A 55g is a poor choice where as a 120g is a much more stable tank. The bigger the footprint relative to the height, the better it will resist any tipping motions.
davocean
Active member
Yeah I live in CA too, all my stands have a ply top and bottom attached by screws and they tie the framing together.
That alone probably gives plenty of shear strength, and your skin will increase strength as well whether that be ply or 1x
We do have to build a little differently here compared to places that are earthquake free.
That alone probably gives plenty of shear strength, and your skin will increase strength as well whether that be ply or 1x
We do have to build a little differently here compared to places that are earthquake free.
Ridesbikes216
New member
Thanks davocean and rocketengineer! Huge help! One more question: would skinning the back but not the front have the same effect or would skinning the front in addition and then cutting large access areas for doors still add rigidity? I ask because I would like post-to-post doors on the front for easy access. Also, would 1/2" plywood be enough?
RocketEngineer
Space is big.
Yes, and yes. Just keep in mind that you get the best bang for your buck if you start with a full sheet and cut out the center as compared to cutting strips.
Ridesbikes216
New member
Rad, that was the plan. I now know how to move forward with my project! Thanks again!
Kbel1969
New member
I notice a lot of people overbuilding their stands. Way to much unnecessary lumber. All that is needed are 2 vertical supports on each corner, and people putting the extra piece inside those 2 are just wasting space, and creating unnecessary weight, it adds nothing as far as support. On the 2 horizontal pieces, just bolt a piece of 1/8" plate steel, and countersink the bolts, you will create about 5000 pounds of support, and won't need a center brace. And the skin will stabilize the stand from lateral forces.
Ridesbikes216
New member
One more question! If one were to rotate the green pieces in the original diagram so they lied flat against the outer pink legs would it be as strong?
