Cody

Hi,

I have a couple of questions on building an aquarium stand. I'm planning a stand for a 72 gallon bowfront.

First, is it possible to put the cabinet on legs? I'm thinking of a plywood case attached to either a separate base or attached to 4 feet (like bun feet but a different design). Or a frame and panel with mortise and tenon construction. Can any of those designs support the weight of the tank?

Second, I would like to make to cabinet rectangular, but have a curved top to match the bow of the tank. Any problems with the extra overhang and the tank weight?

Thanks for your help!

dennis

Cody welcome

Sounds like you already know a bit about htis stuff. You have the ability to do mortise and tenons? Either idea will support the weight if you build it correctly. Also, the slight overhang will be fine. What are the exact dimmensions of your tank? Can you be more specific as to what you had in mind? Maybe a pic of something else or even a paint drawing. The basic thing to remember with supporting weight: the strongest scenerio is when the weight has a direct path vertically to the floor/ground. A 72 gallon wil weigh about 650lbs or so. Think that that is the weight of ~3 of you bigger friends. Not to bad reallly. SOund construction and you will be fine. Let me know more and I am sure we can figure it out

Cody

Hi Dennis,

The tank is 48" long. It's 18" wide at the center of the bowfront and 12" wide on each end.

This is similar to what I had in mind for the post and rail cabinet. The face of the cabinet would be flat and just the top would be curved. So are the posts supporting most of the weight on this type of construction and the rails are holding everything together?




Thanks for offering your help!! I'm still pretty new to woodworking, but it's a goal of mine to get into fine woodworking. I've got a garage full of tools, so I'm only limited by time and skill level at this point.

dennis

Thak would work wonderfully. The weight of the legs take all the weight to the floor but hte rails still will support some weight initially. The rails take the weight to the legs. With good mortise and tenon construction and a center leg you will have no problem. The center leg will be very helpful. You will can pretty much go with any size parts you want and still have it be very strong. The thicker top will help that too. I would recomend that you use rails that are atleast 1" thick and 3" high. THis will give a very, very strong rail if you make it from solid wood and use proper joinery.

Let me know what you come up with if you have any questions about joinery, design, wood selection, etc. This looks like a very nice project for anyone and it should not be to hard for a beginner. You will learna lot and build something useful and beautiful. If you feel at all overwhelmed, just break the cabinet down into small parts and deal with little pieces at a time

Good luck and let us, and me, know how it goes. Feel free to ask more questions anytime

Cody

Hi Dennis,

I do have some questions about mortise and tenon joints. I've noticed that some people use a haunched m&t on the apron rail, even on a solid wood top, why is that? I was thinking a full-height tenon on the apron would be the way to go. What do you think?

On the center leg, I'm thinking there probably isn't one on the back of the piece in the photo, but I should include one in my design. I was thinking a bridle joint on the apron rail. Would you do a lap joint on the lower rail or a couple of m&t joints here.

I haven't decided what kind of wood to use yet, but if I'm not able to find it in the thickness I need for the legs will it be alright to laminate two thinner boards together? I've heard that 2x4s glued together are just as strong, if not stronger, than a solid 4x4, is that true?

This is really cool of you to offer your expertise on woodworking. I really appreciate it! BTW, we were just installing 220V in the garage today for my new bandsaw. I can't wait to use it!

MatPat

Hey Cody,

I would make a full height tenon on the apron rail. I don't think the extra work of a haunched tenon would be necessary. About the only time I use a haunched tenon is when connecting door rails to stiles. And then I would only do the extra work on a base cabinet doors where you will actually see the tenon if you didn't use a haunched tenon.

A bridle-joint would work on the center leg for the upper apron. It might be easier just to make a M/T joint for both the upper and lower apron rails. This would only involve one setup. A half lap would work too and would give you the benefit of using some screws (from the rear of course) for added insurance. The screws would also free up some of your clamps for other things, like doors.

Laminated wood for the legs would be stronger than a single, thicker piece. Depending on the thickness it would also be more stable. I have laminated many 2x4's together to make my workbench legs in my shop. 4x4's tend to twist and warp in my experience.

If I just got a new Bandsaw, I would attempt to make the cabinet a bow front to match the tank. It would look much better, at least in my opinion. I would use some MDF to mock-up the first cabinet. This will give you a chance to play with the bandsaw and work out any problems you may encounter with inexpensive MDF before you get to the expensive solid wood. When you're done you should have no trouble selling it for the cost of the materials. If you can't sell it, you could always use it for another tank later on.

If you decide to make a bow-front cabinet, I'm sure Dennis and I can give you some help along the way.

dennis

MatPat is absolutly correct. I would not do a haunched tenon there either, its definately not worth the work

I would actually not go with a full height tenon. Your tenon should stop about 1/2" from the top and bottom of the board. This captures the tenon more, making a stronger joint structurally. Also, having the mortise come out the top of the leg would make the mortise much weaker.

I would add either a back leg or make the back of the cabinet itself fit tight and put a foot in the back. The cabinet, if made well, will be able to support the tank fine without the extra leg but it wont hurd either. Adding a foot would be fast and easy.

Good luck, and, as usual, feel free to ask anytime

Cody

Good point! I didn't think of that. How do you feel about loose tenons vs. integral tenons -- equal in strength or about the same?

I'm wondering how deep to make the mortises if I did it this way. The center leg might be 3" wide. With a mortise on each side of it are there concerns about the tenon length or the mortise depth? Or in other words, how much wood should be left in the center? I hope that makes sense!

I've been thinking the same thing. If you guys are up for the questions I might give it a try. The angled joints seem intimidating at this point. Or am I just making a big deal out of nothing?

dennis

Studies were done a while back to determine how strong certain joints were. It ws discovered that when the joint was mechanically sound, the the strength of the joint after glue up was about the same for loose tenons as it was for regular tenon. So, loose would be fine. What ever is easiest for you to do is what I would go with


If the center leg is 3" make the mortise 1.25 deeb and the tenon 1.125"(1/8") deep to allow a little room for glue. Yo never want your tenon to bottom out.

Angled joinery is not that hard actually. Sometimes wha thelps is to make a fukll size drawing. Make a drawing. You might find that the joinery is not as angled as you think

Luck