Project Information Request - WoodNewb - Woodworking Talk

Mynd · 01-22-2009, 06:49 PM

Hello there,

I have been looking for a place like this for a long time. In my efforts to locate an answer to a question I had about wood I even considered calling a structural engineer.

The question I have is going to probably require a long explanation, so I will post my question and if I need to call someone up let me know.

Question:

How does one design a table 26"h x 60"w x 48"d that will support a ton. There will be a 20"x20"x18" cube reef tank on this along with a sump of the same size, pumps, etc. I want to be able to place the pumps and tanks wherever I want on this table and chances are it will be on one side allowing me room to work ( testing/water changes ) on the other side of the table. So maybe I should be asking how can I put together a table that will support the weight, not split, tip, shift or crack with the load and occasional salt water drip/ spill?

Carefully? LOL - I knew that was coming..

I just have nothing and no one to turn to in designing a table that I can feel secure about. I would like the top to be maple or birch ( I am thinking about 2 3/4" piece glued together so I can screw the top to the base from underneath and not destroy the wood surface in the process. etc..

Can you give me some direction, ideas, advice? I want to do this right.

Appreciate any insight you can give me on this. So thanks.. I am going to have to build this in my cellar since a table that size would not fit through the door. Again, thanks for any and all information.

Kind regards,
Stephen

12penny · 01-22-2009, 07:38 PM

Yur kidding, right?

Mynd · 01-22-2009, 08:43 PM

Uh no... Not really the answer I was looking for... Why would you think I was kidding? Please advise..

Is this not a woodworking forum?

12penny · 01-23-2009, 08:16 AM

Mynd, OOOOOOOOOK. Best place to start.....what tools do you have available to you? Once you have it built, how do you get it out of the basement? I would think the best course would be to use 2"x4"s for the frame of the table then 2 peices of birch plywood for the top. Frame those in whatever wood you would like to finish it off. That should hold the weight. Make sure your floor framing can handle it also. Good luck with your project.

Mynd · 01-23-2009, 08:33 AM

Hello there,

I have all the tools I need to complete the job I am pretty sure. The table will NOT be leaving the cellar office ( that is where the tank is going ) You think I should use 2x4's and not 2x6's or 4x4's for the base frame? Is Birch a good option or should I use oak or something else better? I just want to make sure the table is not going to come crashing down. Should there be a support for the middle of the table as well? That is a lot of area that is not supported. Maybe a leg in the middle as well?

Ideas?

Thanks for the response..

12penny · 01-23-2009, 09:12 AM

2x6 and 4x4 would also be a good choice. Use whatever plywood you like. A center leg would be ok if you think you need it. How much water does your tank hold?

Mynd · 01-23-2009, 09:32 AM

Based on the sizes of the tanks and the water volume the tanks will contain about 250lbs per tank, not including about another 300 lbs for rocks, pumps, equipment. So all in all the complete system should weight about 1000lbs ( over estimate in case I choose to make the tank wider then 20"'s. Displaced over a 20 square foot area. I think that should provide about 50 - 100 or an average 85 lbs per square foot based on the foot print of the tanks in any one spot. Less in other areas. Hence not wanting it to tip over or flip or crack or whatever..

bradnailer · 01-23-2009, 10:15 AM

I'd build a torsion box (2*4 framing and 3/4" ply top and bottom) for the table support then put whatever type of top on the table you want to get the finish you are desiring.

I wouldn't use 2*6 in the torsion box because to me, it would look a little goofy where a 2*4 frame would look like a normal table apron. To gain added strength in the torsion box, laminate two 2*4's together and put a strip of 1/8" metal between the 2*4's. To do the lamination, sandwich the 2*4's with the metal between them then screw them together using 2-1/2" screws, two top and bottom, spaced every 10". If you don't want to use the metal, then just glue the 2*4's together but still screw them together. If it were me, I'd use 4*4's for the legs.

You can build the torsion box from inexpensive pine then trim out the sides with more pleasing wood, the same wood you would use for the top and legs.

Mynd · 01-23-2009, 12:33 PM

I really like the ideas here.. Thanks for the information guys.... Torsion Box was a great key word here and allowed me to see some awesome tutorials.

http://thewoodwhisperer.com/episode-...e-torsion-box/

http://thewoodwhisperer.com/episode-...y-table-stand/

I think I will follow this idea with my own design and the above discussed base wood choices for sturdiness.

Thanks alot for your help. I appreciate your time and efforts..

frankp · 01-23-2009, 01:14 PM

Mynd, first of all, the volume of that tank will hold nowhere near a ton of water. Even if you consider the pumps and extra equipment weigh 1000 pounds, you'll still be well shy of a ton.

I have a 24" by 12" by 18" tank, (29 gallons I believe) that only weighs about 300 pounds. Maybe another 30 pounds for rocks, though with a salt water reef, I guess you could probably say another 200 pounds or so.

For my tank and associated equipment, I built a standard 2x4 frame and used 1/4 inch plywood to face it. The frame is basically a box using 3 inch wood screws to connect the pieces. It's about 24 1/2 inches wide, 12 or 13 inches deep and 48 inches tall. I put two shelves in that hold all our stuff. We have no problems with tipping or weight issues.

Mynd · 01-23-2009, 01:36 PM

Thanks for the information Frank... I appreciate it.. The thing is that with my tank there will actually be two and I have not decided if I want the main tank to be 20x20 or it might actually end up being 20x40x18. It will be close to a 1000 lbs though.. The reason I inquired about building a table that could hold a ton is because it perplexes me why tables and chairs never have weight restrictions applied to them.. Sure I could go out and buy and oak table 26 inches high, but WOULD it support what I want.. Probably.. but you can't be to sure..

I wish that they had weight limits on chairs and tables.. Not that I am heavy or anything but I think people would make better choices knowing the strength of what they are purchasing.

I am going to go with the tension box and maybe make the base a storage area for my water and water change tank ( that I did not include in the original plans.. Might have to add another 10 gallons of water in there for weight, but far below the requirements of a stand that can handle a ton. See how things get added only after a day.

I think in total the weight will be about a 1000lbs. I just want to make sure I do it right and USE the right stuff. There is water involved here and we both know spills happen.

Thanks again for the information and helping out.. I really appreciate everyone's advice..

frankp · 01-23-2009, 03:14 PM

Mynd, I see. I had missed the concept that there would be multiple tanks or one much larger tank. I would say, though, building a six leg table will be sufficient. Make sure you build stringers in the middle of the table to support the weight there. Attached should be an image of basically what is a mildly unattractive frame that will do the trick. Use simple wood screws or build with some more beauty and strength by doing mortise and tenon type joints etc etc. There are plenty of options, the one I've shown actually being the weakest choice (butt joints.)

I just put a glass top on the thing so you can see how the frame goes together. The beams are supposed to be 2x4s but you can up that a bit if you feel the need. I'd just make the corner posts 4x4 if you're really worried about it.

Skin this thing with some simple plywood and you've got yourself a workable box. If you want to make it more table like, you could cross brace the corner legs with some shelves on the bottom and remove the bottom stringers. In the case of a table some 3x3 legs might work quite nicely without having that "overbuilt" feeling.

Most of the Aquarium cabinets I've seen in shops have been basically this frame made with standard 2x4s and a skin, as I've suggested. I've never seen any that were done elegantly, but I've seen this design hold 300 gallon tanks and larger.

As for water, just use a sealant that repels water. Either some form of polyurethane or something similar that will prevent the wood from soaking up the water too quickly so that you can wipe it up when you spill.

Mynd · 01-23-2009, 04:06 PM

Very Nicely done.... I use google sketchup for my stuff. Nice quick image. Designing a new tank myself but unsure of its true dimensions at the moment.

There will be changes, but I plan on doing my table design in sketchup as well. Thanks for all the help!

bradnailer · 01-23-2009, 05:24 PM

Welp, if you are going to close in the bottom, that changes everything. No need for a torsion box.