# I have an idea in my head for a workbench but . . .



## Voltage (7 mo ago)

HI,
I am going to build a couple of workbenches on the cheap thanks to inflation but they just need to be sturdy and not droop later on. I need them for electronics work bench and 3D printers mainly. My plan is to use 2x4's for the legs but they will be doubled from the floor up to the first top (3/4 sheathing) and then another to the next top and then the final to the 3rd which is the top of the unit. So it's kind of like a wall as far as 4- 7 foot "king studs", then the "jack studs" will separate the layers. I'll probably have to draw a picture to make it more clear. I already cut the plywood and to get the most for my money I cut 32" lengthwise on 2 4x8 sheets so I have 2- 32" bench tops and the remaining 2- 16" pieces together will be used for the top (just a hair under 32" total due to the kerf). So first I will cut 4- 2x4's to 7 foot for the outside legs. Then I will cut 4 pieces for the height to the first layer (less 3-1/2" for the 2x4 horizontal brace or stiffeners). Then the 32' x 8ft bench top. and work up to the next level the same way. I will also add 2x4 bracing from front to back between the 8 ft frame. Anyway, does that sound like it will be strong enough?
Thanks,
Voltage


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## Voltage (7 mo ago)

A partial pic to see what I am thinking.


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## Voltage (7 mo ago)

Top view of left front leg first layer header under first plywood top.


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## Voltage (7 mo ago)

And a top view of the bracing under the plywood top that is 8 foot by 32" across. I don't know how many cross braces I need to use here for strength vs overkill. I guess I will go eat breakfast as it's almost noon!


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## John Smith_inFL (Jul 4, 2018)

if you REALLY wanted to prevent any kind of droop in the future, you might consider the 1x4" square aluminum tubing used in the patio screen industry. Also, the 2x2 or 2x3" tubing used for the screens.
But of course with enough vertical 2x4s, you can do that just as well.


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## Voltage (7 mo ago)

John Smith_inFL said:


> if you REALLY wanted to prevent any kind of droop in the future, you might consider the 1x4" square aluminum tubing used in the patio screen industry. Also, the 2x2 or 2x3" tubing used for the screens.
> But of course with enough vertical 2x4s, you can do that just as well.


Well for now I am stuck with what I bought. The pic that looks like a ladder above is directly under the the plywood top. In the past I would/could put a 2x4 or 4x4 just under the center for support and do the same between the layers. It just makes for a post in the way under the table and on each layer.


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## DrRobert (Apr 27, 2015)

Is this a woodworking bench or a general hobby bench?

If ww’ing the top should really be thicker.
But it all depends on what you’re doing. Using sheet goods minimum 2 layer, preferably 3, 4 even better. MDF is a good choice for the top. 

Lap joints will be stronger but you’ll probably be ok.


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## Voltage (7 mo ago)

DrRobert said:


> Is this a woodworking bench or a general hobby bench?
> 
> If ww’ing the top should really be thicker.
> But it all depends on what you’re doing. Using sheet goods minimum 2 layer, preferably 3, 4 even better. MDF is a good choice for the top.
> ...


It's just for 3D printers on the 2nd shelf and electronics hobby stuff on the main bottom shelf. I was going to add a piece of hardboard for a nice surface. I will mainly be doing soldering and pcb electronics work with the benches.


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## Tony B (Jul 30, 2008)

If you want a really stiff top made of plywood do this:
Use your table saw top or anything flat and true. 
Lay one piece of ply on the selected flat surface
1) Start about 2" away from the outside edge and drill holes for screws approx 6" apart and make a grid pattern. Dont have to be exact.
2) Put that board aside for a few minutes and lay the other board on the table top. Apply glue to the entire surface with a glue roller or cheap paint brush.
3) Now take the sheet of ply you put aside, lay it on top of the glued surface and with a drill/driver and screws, screw it all together.
4) The next day, either remove the screws or leave them in place. I usually leave them in place.
5) Flip the two pieces, glued and screwed as one, over to the side with no holes or screws showing and now you have one solid flat top, 
6) try spanning it across 2 saw horses or whatever and see how stiff it is. 

I have been using work tables made like this for over 30 years and never had a problem with it.
BTW, this should be 3/4" ply each for a total thickness of 1 1/2"


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## Voltage (7 mo ago)

Tony B said:


> If you want a really stiff top made of plywood do this:
> Use your table saw top or anything flat and true.
> Lay one piece of ply on the selected flat surface
> 1) Start about 2" away from the outside edge and drill holes for screws approx 6" apart and make a grid pattern. Don't have to be exact.
> ...


 Sounds like a great idea but I was trying to save some $$ as plywood is $50-$65 a sheet for 3/4 and that is just sheathing. With my method above and the horizontal 2x4 braces from front to back, how many would be enough to add the strength there? 
Thanks


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## _Ogre (Feb 1, 2013)

You mentioned bracing, but show none. Without diagonal bracing it will fold up by leaning on it. Even the 3D printer would shake it terribly. X bracing in back and Z on the side will help


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## Voltage (7 mo ago)

_Ogre said:


> You mentioned bracing, but show none. Without diagonal bracing it will fold up by leaning on it. Even the 3D printer would shake it terribly. X bracing in back and Z on the side will help


The frame has 2x4's in the upright position like a header but they are single width. They go around the whole perimeter on each layer. The braces I spoke of are underneath the plywood between the front and back 2x4 to avoid warping and add strength. Kind of like a ladder laying flat under the plywood. But I can easily add some bracing so that's not a big deal.


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## Tony B (Jul 30, 2008)

For what you are wanting it for, your original sketch should be strong enough. My idea was to give it rigidity and flatness.


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## Voltage (7 mo ago)

Tony B said:


> For what you are wanting it for, your original sketch should be strong enough. My idea was to give it rigidity and flatness.


Ok, great. Just don't want to mess up right off the bat. Prices are whats killing me. I have a lot of workbenches in my shop with single 3/4 plywood tops and they are fine. I did use 2x6 frames though and 4x4 legs. In fact I built one by putting a bunch of benches together for a large project I was making at the time. It's like 16x16 square and loaded with junk. 😄


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## Tony B (Jul 30, 2008)

Everyone here has a different view as to what is necessary to have and what is nice to have and what is practical.
That is why you get a lot of responses.
Have fun - that's the main objective.


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## woodnthings (Jan 24, 2009)

Wood is very strong in compression, vertical loads and that also means plywood.
Plywood is prone to bending when oriented horizontally and needs supports every 16" to 24" depending.
An open framed rectangle will collapse without a diagonal brace or a thin back.
A very rigid worksurface can be made from two pieces of plywood with a grid glued in between them, called a "torsion box".
I made one for my outfeed and assembly table, measures 30" wide X 10 ft long and 3 1/4" grid of 1 X's in between.





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## Voltage (7 mo ago)

woodnthings said:


> Wood is very strong in compression, vertical loads and that also means plywood.
> Plywood is prone to bending when oriented horizontally and needs supports every 16" to 24" depending.
> An open framed rectangle will collapse without a diagonal brace or a thin back.
> A very rigid worksurface can be made from two pieces of plywood with a grid glued in between them, called a "torsion box".
> ...


That looks good and strong etc but if I wanted to do it less expensive but still strong enough, which one of the ways to do it in the pic would suffice? I also plan on adding a 1/8" sheet of hardboard. Or if I used a method similar to yours could I use a piece of 1/8" Luan plywood on the underside and the 3/4 plywood on the top and get good results? I have a bunch of 1/8" Luan. And I forgot to mention I was planning on putting a 2 foot x 8 foot piece of pegboard across the back of the first section to hang tools etc. That will add some bracing too.









On the image above would the left setup with 3 cross members be sufficient or should I use 5 like on the right? The table top is 8 foot x 32".


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## kiwi_outdoors (Jan 15, 2020)

consider a hollow core door for the top?


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## woodnthings (Jan 24, 2009)

kiwi_outdoors said:


> consider a hollow core door for the top?


The trouble with hollow core doors is there's not solid structure anyplace inside to attach a vise or much of anything else, if that's a requirement?
They would be fine for a computer desk with a clamp on lamp or a drafting table.
Attaching legs or end panels is another issue unless you can have them at the very ends where there is some structure. 
Strong adhesives and corner blocks to add more area would be my suggestion. a few screws would be OK.
If you make a "sandwich" with a block on top to distribute the force that would work, but it would definitely be in the way as a raised protrusion.


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## Voltage (7 mo ago)

kiwi_outdoors said:


> consider a hollow core door for the top?


No, because I already bought and cut the 3/4" plywood that cost me over $200. But that would work for some uses but probably not mine as its a triple-decker and needs to be a little tougher than that. Good idea though.


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## Voltage (7 mo ago)

Well here she is . . . My plans changed along the way and decided 2 tier was better than 3 for best amount of space for the 3D printers. I think it turned out pretty good for just making up some plans and making a few adjustments along the way. I am going to put a steel square tube with flanges and an adjustable end under the bottom section so it _can't_ warp in the center. And also another one on top of the first level to the bottom of the upper level for same. It is very heavy and those triangles worked perfect. I used a silvered gray stain (one coat) and 5 coats of the oil modified water based polyurethane to finish it off. Now I am looking at desk mats so I don't ruin it when I get all my electronics stuff set up.


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