I have been working on a design for a stand for my 20 gallon aquarium to sit on. Each side of a square is 2 inches long in my diagrams. Pocket hole joints are indicated by double arrows, while the lil box thingies are L brackets. I plan to attach the top to the legs using figure 8 brackets.
Are there obvious ways I could improve my design? This will be my first serious woodworking project.
Here are the side and top views:
Agree with others about the joints. I had a 20 gallon aquarium on an old pine table my dad built. Mortise and tenon joinery on the aprons, plus angle brackets to hold the legs in (which were 2.5"x1.5"). This is 50 years old and quite frankly over-built.
The top started buckling, cracked, and the legs splayed a little under the load after a year. It’s mostly healed itself in the ten years since the aquarium has been gone, but never underestimate how much weight an aquarium can put out.
He designed a pine stand for a 70 gallon aquarium after that, and the floor buckled before it did. The top is slotted pine, like this, (for condensation which can damage wood) with small spacer blocks in between. I believe these sit on 4x4s that are mostly hidden on the inside by being part of panels and frame. Mostly mortise and tenon and bridle joints.
Most of the examples online use construction lumber on the inside, and face frames on the outside.
I just put my finger on the problem with your design. It’s Oops: All face frames.
A face frame is a low-load structure attached to the front of a cabinet mostly for appearance. It may add some rigidity to a cabinet, it might be a mounting point for doors or something but doesn’t bear the main load of the cabinet.
If I read your drawings correctly, you’re butt jointing four face frames together into a box. 2-inch wide rails and stiles attached with pocket screws.
The problem really isn’t the lumber, it’s the joints. I bet this table would hold the weight of a fish tank…for awhile. But, if the floor isn’t perfectly level, if you lean on the tank a little while feeding the fish or changing the water, that applies a racking load to all those butt joints. Which is effectively what a pocket screw joint is; the screws really don’t add much strength beyond the glue, especially against tension and racking loads. If this thing starts leaning, the 160 pounds of water plus glass, gravel, pump, fun little castle etc. is using the length of those boards like a crowbar to pull on all those screws.
If you want to keep the construction mostly like this, what I would do is increase the board width to 3 inches, do rabbet joints on the corners, cut a rabbet in the front leg for the side leg to fit into it. That’ll eliminate the need for those corner brackets, it’ll be much less of a pain in the pants to assemble as well. And join the rails to the legs with half-lap joints, that’ll be much stronger against racking.
Needs proper joinery. Mortise and tenon would be strongest. I’ve tried “cheating” by using those cheap dowels and a drill for something like this, but it eventually failed, so I do mortise and tenon now. Wedged and/or pinned tenons would be even stronger, but I haven’t tried those yet. I also haven’t tried the stuff meant for power tools, like biscuits, so dunno how strong those would be.
Mortise and tenon joinery is good, but pocket screws with glue is also extremely strong.
Dowels, when used with actual wood (not press board) is also plenty for this application.
Looking at this design, the main issue is racking forces, which M/T joints may hold up slightly better to, but a thin sheet of 1/4" plywood stapled or glued on the back and sides would also lock this into place and prevent racking.
Really, this design is probably fine, but there’s a handful of details that aren’t shown, and would be critical to the success.
Isn’t that a bit small for a whale?
They sell star trek graph paper?
So if I’m reading this right, your “legs” are 3/4" thick, 2" wide, and 29" long. That strikes me as a little light for the load in question. I don’t understand what the front and back are going to look like at all. I also don’t quite understand the…feet? Are we doing lap joints with boards at the bottom?
You’re attaching whatever the front and back will be with L brackets?
What tools do you have available to you?
Aye captain, maybe you should just replicate it.
I’m not an expert woodworker but I did have aquariums when I was young.
A 20 gallon aquarium, all set up, can weigh more than 200 lbs. The stand will be under quite a bit of stress and if it fails…
One of my first non-trivial woodworking projects was a stand for a 20 gallon aquarium but I didn’t build it from scratch: I revised an existing table with stout legs. It’s a long time ago, but the legs were tapered and maybe 3"x3" at the top, or maybe even 4"x4". The aprons were maybe 1/2"x4" with mortise and tenon joints into the legs. The top was 3/4" plywood. I don’t know what the wood was, but might have been pine. It supported the aquarium fine, but it was much stronger than your design due to the stouter legs and more substantial aprons. The design was something like Build a Sturdy End Table, except for the mortise and tenon joints instead of dowels to join the aprons to the legs.
I would be hesitant to put a 20 gallon aquarium on a table of your design. The legs and bracing seem a bit weak. If the joints aren’t very tight, if it starts to go over, there might be excessive loads on the brackets and pocket screws, and it might collapse. It might be fine, but I would definitely loose sleep. I had a 20 gallon aquarium fail once (the aquarium, not the table). It’s a lot of water, a lot of mess and very hard on the fish.
If it were my first serious project, I would look for a proven design, specific to holding the weight of an aquarium. There are many designs available, some with nice build videos. All that I have seen are more robust than your design, even for 10 or 20 gallon aquariums.
If I were going to proceed with something like your design, assuming soft pine frame, I would use 2x4 or larger for the legs, wider aprons and angle braces at the corners.
My dad needed a very clear, more scratch resistant glass for a product he was working on. Up until then, the best you could get was by going to glass companies and getting sapphire coated glass. He searched a chemistry book of compounds and found what he was looking for. Based on the structure, the qualities were known, but it hadn’t ever been created. So he then to a chemical company and worked with them to make it. It’s essentially aluminum oxide (corundum/ruby or sapphire depending on the color. His was colorless.)
When he unveiled it to the company he worked for, he called it “transparent aluminum”. He said one guy at the back of the room caught the Star Trek reference.
More triangles
can’t help you on the design, but I just wanted to say that I love graph paper.
have a great time building a pedestal for your majestic water friends. :)
As one commenter said, triangles are good. They’re very good at handling loads. Other than that, the best way to learn how to design and woodwork better is to just get out and do it! You’ll learn more as you go.
