DIY Stands Template and Calculator

[Rhodophyta]

I don't know why I can't get this but I just can't picture how you have this built.

Go to a development where they are building a house and look at one that has the floor started. The joists are on 16" centers or sometimes 12". The ends of the joists are supported by the foundation, and are kept from twisting by their attachment to the band board or boxing. It's pretty close, although sometimes now there may be a raceway for utilities making it harder to see the general design.

 

[Amon Ra Reptile]

I get that ok but where is the plywood located in your build?

 

[Rhodophyta]

I get that ok but where is the plywood located in your build?

If you think of the 2 by 12 and the 2 by 8 as pieces of sliced bread, the plywood is the sliced turkey between them. A half inch of plywood provides as much resistance to deflection as another 2 by. Don't forget the mayo! (glue)!

 

[Amon Ra Reptile]

I gotcha so your using a piece of ply the width of the 2x8. Makes sense now. Lol

 

[Rhodophyta]

I gotcha so your using a piece of ply the width of the 2x8. Makes sense now. Lol

You have the idea now, except it was 11 1/4", the width of the 2 by 12, and the ends of the 2 by 4's butted against it for the "top of the sandwich" although the analogy is getting stretched at this point.

 

[jnjsad]

strength?

strength?

I have a rimless Reef Savvy tank. Dimensions are 36x24x16 = 60 gallon tank. My plan is to create a furniture grade stand to go into my office. Here are the specs. What do you guys think?

Stand will be 36 ¼ x 24 ¼ using ¾ hardwood frame, plywood sides and solid wood doors. No center brace or cross brace. ¾" solid hardwood plywood top with 3/4" foam. Thinking poplar to be the choice in wood.

Thanks in advance for your input.

 

[Donw]

My plan is to create a furniture grade stand to go into my office.
Stand will be 36 ¼ x 24 ¼ using ¾ hardwood frame, Thinking poplar to be the choice in wood.

Thanks in advance for your input.

Furniture grade would not have an internal frame. Poplar is not hardwood.

Don

 

[Amon Ra Reptile]

Yea poplar is sold as a hardwood often but is not.

 

[jnjsad]

I am going back to the drawing board in the am on this stand. My brother is a former carpenter turned cabinet maker and this was his design. On my 300 gallon tank stand, I did 2x6 frame wrapped in plywood. This is the smallest stand I've done but want to depart from the 2x4 boxed frame structure.

I estimate total weight stand must sustain is roughly 700lbs. Anyone have suggestions on how to build this w/out doing the normal 2x4 frame?

 

[Rhodophyta]

The ply adds alot of strength to the 2x12 if its laminated with glue. If not laminated it adds just the strength of the plywood itself which will add rigidity to the stand. The problem with gluing is there is to much timber in a 2x12 and its going to expand and contract. If the plywood is glued and it is trying to hold back the expansion or contraction the 2x12 can split or break. The expansion is not going to be held back by any woodworking glue. The wood you buy at the home center is not completely dry and will move quite abit after you get it in a heated house. Its ok to laminate ply to a 2x4 or 1x4 but not a good idea with a 2x12.

Don

If you let the wood stabilize in the room it will be in before assembly, and if you maintain the same temperature and humidity range in the room, subsequent expansion and contraction should be greatly limited. If you do get catastrophic expansion, the break will happen in the wood and not in the glue joint. You could laminate two 1 by 12's together to make one 2 by 12 with less chance of twisting or bowing than a solid piece of wood, but it is hard with the average pile of wood clamps to do this on a large piece of wood. However if you move a lot or store the stand unused for a few seasons in Grandpa's barn, a solid, composite, or laminated wood stand is going to be at risk to expansion and contraction.

 

[Rhodophyta]

So if that's how it was done why not just use 2-2x12s with the plywood in between? Also, does the plywood layer really add that much strength?

You don't use two 2 by 12's because you want the ledge created by the 2 by 8 to rest the 2 by 4 crosspieces on. Setting the 2 by 4's on top of a rail would not give anything to tie them into to resist twisting.

The grain in each layer (ply) of wood in a sheet of plywood runs in different directions which gives it more rigidity than solid wood. That's why two 2 by 4's with a half inch plywood sandwich inside is much better properly oriented to use than a solid 4 by 4 even though both have the same outside dimensions.

 

[Rhodophyta]

Yea poplar is sold as a hardwood often but is not.

Poplar, including tulip which is harvested as "yellow poplar", is the softest and easiest to work of the hardwoods, and yet pound for pound it is the strongest. That is why the tulip tree is the tallest of the deciduous hardwood trees in much of North America. The weight of exceptionally dense hardwoods like oak and ironwood limit how big those trees can grow in spite of dimensional strength.

http://www.fpl.fs.fed.us/documnts/pdf2001/balat01a.pdf

http://www.ahec.org/hardwoods/guide/tulipwood.html

 

[Donw]

If you let the wood stabilize in the room it will be in before assembly, and if you maintain the same temperature and humidity range in the room, subsequent expansion and contraction should be greatly limited. If you do get catastrophic expansion, the break will happen in the wood and not in the glue joint. You could laminate two 1 by 12's together to make one 2 by 12 with less chance of twisting or bowing than a solid piece of wood, but it is hard with the average pile of wood clamps to do this on a large piece of wood. However if you move a lot or store the stand unused for a few seasons in Grandpa's barn, a solid, composite, or laminated wood stand is going to be at risk to expansion and contraction.

Sorry but not correct. Lumber does not become dimensionally stable until its dried to 6% and then and only then will it become acceptably stable meaning it will still move but will move an acceptable amount in the average dwelling.
Constuction lumber is not kiln dried to 6% and takes quite some time after being in an average home to dry to 6%.
Lumber moves most across its grain. Binding the grain with plywood causes unpredictable behavior and even self destruction. Binding a 2x4 is not going to cause much of an issue but a 2x12 depending on the moisture content at time of binding can cause serious issues.

Don

 

[Donw]

Poplar, including tulip which is harvested as "yellow poplar", is the softest and easiest to work of the hardwoods, and yet pound for pound it is the strongest. That is why the tulip tree is the tallest of the deciduous hardwood trees in much of North America. The weight of exceptionally dense hardwoods like oak and ironwood limit how big those trees can grow in spite of dimensional strength.

http://www.fpl.fs.fed.us/documnts/pdf2001/balat01a.pdf

http://www.ahec.org/hardwoods/guide/tulipwood.html

Poplar is not hardwood. Hardwood in the furniture industry is determined by its ability to hold up to normal everyday wear and tear. Hardness is determined by Janka rating not whether or not the tree has leaves or whatever marketing strategy the timber industry is using on that day of the week.

Hardwood starts at about 950 and only goes up from there. Poplar is best suited to architectural trim work such as crown mouldings and base mouldings to be applied to walls and not receive daily wear and tear.

Don

 

[Donw]

I am going back to the drawing board in the am on this stand. My brother is a former carpenter turned cabinet maker and this was his design. On my 300 gallon tank stand, I did 2x6 frame wrapped in plywood. This is the smallest stand I've done but want to depart from the 2x4 boxed frame structure.

I estimate total weight stand must sustain is roughly 700lbs. Anyone have suggestions on how to build this w/out doing the normal 2x4 frame?

Yes its easy to do. People use 2x's because they dont have a shop full of tools not because its actually needed. If your brother is a cabinet maker he should have the equipment to join three plywood sides with dados and dado in a bottom panel. Your front face frame is the only thing that changes from traditional AWI cabinetry standards. The front face frame top rail should since it exceeds 24" be reinforced. This is usually easiest with a strip of BB ply. Your brother will know what Im talking about without muddying up the thread further.

Don

 

[Rhodophyta]

Poplar is not hardwood. Hardwood in the furniture industry is determined by its ability to hold up to normal everyday wear and tear. Hardness is determined by Janka rating not whether or not the tree has leaves or whatever marketing strategy the timber industry is using on that day of the week.

Hardwood starts at about 950 and only goes up from there. Poplar is best suited to architectural trim work such as crown mouldings and base mouldings to be applied to walls and not receive daily wear and tear.

Don

Sorry, not my call. Poplar is hardwood. Someone else makes these definitions and I don't get to change them to suit my opinion. It sure is a soft wood, but it is not softwood. For many years I had an unpainted picnic table that was made from yellow poplar that my wife liked the unpainted look. She had our family eating every possible meal out on that table all while our kids were growing up. I also have a couple of these trees growing in my yard, messy always dropping something, leaves, flower petals, hard seeds, and other weird stuff, a magnet for tiger and spicebush swallowtail butterflies, but at 100 feet or taller they are way taller than the oaks and the beech trees, ash trees, and maples.
http://www.nativetreesociety.org/bigtree/tallest_hardwood.htm

 

[Donw]

Sorry, not my call. Poplar is hardwood. Someone else makes these definitions and I don't get to change them to suit my opinion. It sure is a soft wood, but it is not softwood. For many years I had an unpainted picnic table that was made from yellow poplar that my wife liked the unpainted look. She had our family eating every possible meal out on that table all while our kids were growing up. I also have a couple of these trees growing in my yard, messy always dropping something, leaves, flower petals, hard seeds, and other weird stuff, a magnet for tiger and spicebush swallowtail butterflies, but at 100 feet or taller they are way taller than the oaks and the beech trees, ash trees, and maples.
http://www.nativetreesociety.org/bigtree/tallest_hardwood.htm

Poplar is not hardwood for the purposes of this discussion which is furniture and home furnishings. Hardwood has nothing to do with the height of a tree. It is a generic term used for trees with leaves. Each industry has its own wood rating and determine whether a wood is suitable for its particular industry. This discussion is about furniture period. Poplar lacks the hardness to be used for furniture and is not considered hardwood by AWI standards. The set standards for building practices by professional cabinet makers and furniture makers.
Im not sure why anyone would care how tall a tree gets and that has nothing to do with hardwood. Im assume you are confusing my 950 starting point as tree height, its not. It the Janka rating. Poplar has a Janka rating of just over 500 IIRC which is not much harder than pine or even basswood.

But enough about Poplar and back to the subject.

Don

 

[bishop40k]

I just got done building my 2nd stand (first one had some pretty nice sized gaps between verticals and upper frame), and noticed that my vertical pieces are not perfectly straight on the vertical plane. Less than 1/16 on a 24" level. Stand is already screwed and glued.

Is this a major problem, can it be fixed? Tank going onto it is a rimmed 75 gallon AGA RR.

 

[Floyd R Turbo]

The point of the stand is to have the vertical members in contact with the top and bottom frame so that the load gets transferred from the top frame to the bottom frame. Then the vertical pieces on the inside of the legs give a place to screw everything to if you don't care about hiding the heads with pocket screws.

If you're saying that the stand is racked, that is the top is leaning to one side such that the entire stand is not plumb, that's not desired, but you're only 1/16" off on 24" and that's a pretty insignificant amount IMO. The screws and glue should take care of any torque effect. If you skin the stand this will help even more. If you are really worried about it, add a diagonal cross brace on the back of the frame, you can make one that fits inside. But I personally wouldn't worry that much, this stand design is so solid.

 

[SPotter]

so i just got done building a stand for my frag tank that will be 48x24x16 and 80g total volume. I followed the original plans in this thread and used 2x4's for the entire build. After skimming thru some of the split thread I came across a post that suggested 2x6's should be used for the top box with tanks that are 48x24. Should I rebuild the top box or leave it as it is?