Interlocking workbenches

[Joe Fry]

All... I am working on designing a workbench/assembly table/infeed/outfeed that will consist of either four 2'x4' sections, or two 6'x4' (2' wide) L shaped sections. In either case the sections will interlock to form a 4'x8' assembly table (see attached image for possible arrangements)

layout.jpg

The reason I want to do this is so that I have a large flat area for assembly and breaking down full sheets with a circular/track saw, while having the flexibility to use it in sections for other purposes (infeed/outfeed, benchtop tools, etc.

While designing the structure and tops is relatively easy, the part I am having a hard time with is how to lock them together and have them align such that the combined top is flat, even if the floor is not perfect. Obviously I would need something to align them, and something to clamp them firmly together.

I do intend on using some sort of retractable casters/lifters and leveling feet; but it would be frustrating to get the separate pieces dialed in to create a flat surface using leveling feet alone (with four sections that would be 16 feet to adjust). I would expect that with most projects I do, they will start together, but will be apart by the time I finish.. so I want them to come apart and go back together relatively quickly.

I was envisioning using latch clamps like these ​https://www.amazon.com/dp/B07K1QJ34Y/ref=cm_sw_em_r_mt_dp_U_RuRTCb4Q0R2J2 to hold the units together... and a large version of this: https://www.carrlane.com/en-us/produ...e-locator-pins, (essentially a cone shaped pin that slides into a cone shaped socket) that ensures precise alignment as the units are pulled together by the latches.

Has anyone done something like this? Any thoughts on where I could get large alignment pins/bushings? Any alternative thoughts on how to accomplish what I am after? Is this a dumb idea?


Thanks!

[George Yetka]

I watched a youtube video about a build like this he used magnets that worked in multiple configurations

https://www.youtube.com/watch?v=PcrTKmO6ttA

[Joe Fry]

I watched a youtube video about a build like this he used magnets that worked in multiple configurations

https://www.youtube.com/watch?v=PcrTKmO6ttA

Thanks for that... his goals are very similar to mine, so I know I'm not crazy.... I just want something a bit more solid than the magnets to tie everything together, and I really want the joined top to be as close to flat as possible when the units are joined.

I'm currently playing with the idea of edging the MDF+Hardboard worktop with hardwood that is tapered outward on some edges and inward on others so they mate up... as in the attached image. As the units are clamped, it would force the top into alignment. Obviously the supporting cabinet bases would need to be built square to the tops to ensure the joined tops are flat. I will likely use plywood rather than dimensional lumber for the reasons he mentions at the end of the video.

layout.jpg

[Jim Becker]

The idea you show in post #3 was what immediately came to mind when you asked the question...just a simple way to key things together. I will suggest that you give carefully consideration to how you proceed with supporting the individual surfaces/whole assembly because there is GREAT VALUE in height adjustability. Sometimes, a simple base with boxes or interlocking supports for different heights is a better solution than fancy wheels and so forth. Especially for assembly work. Height can matter for both access and for worker comfort. Trust me on that.

[Joe Fry]

The idea you show in post #3 was what immediately came to mind when you asked the question...just a simple way to key things together. I will suggest that you give carefully consideration to how you proceed with supporting the individual surfaces/whole assembly because there is GREAT VALUE in height adjustability. Sometimes, a simple base with boxes or interlocking supports for different heights is a better solution than fancy wheels and so forth. Especially for assembly work. Height can matter for both access and for worker comfort. Trust me on that.

I have given a lot of thought on how I want to do the height adjustable legs, so I have an idea of how I want to do it. What range do you think is ideal. I was aiming for 28" - 36" (table to counter height)... but do you recommend lower or higher?

I'd be happy to see what kind of height adjustment solution you recommend. Keep in mind that I intend to have some storage in each of these sections, so something that requires that I lift the table manually would not be ideal.

Thanks for the input.

[Carl Beckett]

I have an outfeed/sanding table that I attached to a small workbench. I simply used screws, and take the screws out from time to time, but only do it occasional. Have thought many times I should switch to a bolt with a knob to pull it together. (or even a threaded insert and machine bolt, it really is no big deal to use a socket driver - but a hand knob is a nice touch). Or one of those hook/ lever case latches would be slick on the underside.

I like the tapered cleat idea - which could be tapered to whatever angle needed (the steeper the angle the more positive the alignment. Or if you had a Domino simply putting some larger dominoes in (and gluing to one side) would be a simple method.

Tables with leaves in them often use dowels. Pretty tried and proven method.

[Jim Becker]

Joe, ultimately, the range of variable height is kinda tied to the type of work you tend to do or intend to do, as the case may be. Surprisingly, I've been using my Adjust-A-Bench a whole lot lowered down to low desk height (about 28" at the top of the bench top) with a chair for some of the kinds of work I've been involved in since getting my CNC machine. It goes up pretty high, too, to approximately 44" for standing up to work on small stuff without bending. I really haven't used it "up there", however. I'm guessing that the highest regular height I've used from time to time is about 40" with most work over time at about the typical 34-36" height of my stationary tools.

Since you are using the area below at least one of the units you propose, then the type of modular height setup I mentioned above might not suffice because these elements are essentially knock down, interlocking supports or just rectangular boxes. The biggest challenge beyond "how to vary the height" is going to be "how flat is the floor" so you can get multiple surfaces at the exact same height without cumbersome shimming, honestly. A flat, co-planer surface is kinda important for assembly work.

[Joe Fry]

I have an outfeed/sanding table that I attached to a small workbench. I simply used screws, and take the screws out from time to time, but only do it occasional. Have thought many times I should switch to a bolt with a knob to pull it together. (or even a threaded insert and machine bolt, it really is no big deal to use a socket driver - but a hand knob is a nice touch). Or one of those hook/ lever case latches would be slick on the underside.

I like the tapered cleat idea - which could be tapered to whatever angle needed (the steeper the angle the more positive the alignment. Or if you had a Domino simply putting some larger dominoes in (and gluing to one side) would be a simple method.

Tables with leaves in them often use dowels. Pretty tried and proven method.

Dominoes and dowels ensure alignment, but they require the parts be closely aligned to begin with. If I am attaching a couple of heavy benches with full cabinets, I cannot guarantee that I can get them in plane so that the dowels or dominoes would work due to variations in my garage floor.

Knobs might be a good alternative depending upon how I end up building it... I certainly am not committed to latches, they were just a thought on how i could pull them together quickly.

Thanks for the input!

[Joe Fry]

Joe, ultimately, the range of variable height is kinda tied to the type of work you tend to do or intend to do, as the case may be. Surprisingly, I've been using my Adjust-A-Bench a whole lot lowered down to low desk height (about 28" at the top of the bench top) with a chair for some of the kinds of work I've been involved in since getting my CNC machine. It goes up pretty high, too, to approximately 44" for standing up to work on small stuff without bending. I really haven't used it "up there", however. I'm guessing that the highest regular height I've used from time to time is about 40" with most work over time at about the typical 34-36" height of my stationary tools.

Since you are using the area below at least one of the units you propose, then the type of modular height setup I mentioned above might not suffice because these elements are essentially knock down, interlocking supports or just rectangular boxes. The biggest challenge beyond "how to vary the height" is going to be "how flat is the floor" so you can get multiple surfaces at the exact same height without cumbersome shimming, honestly. A flat, co-planer surface is kinda important for assembly work.

Thanks for your input on the height.... will probably aim for 28" minimum and get as much lift as I can.

I am absolutely in agreement with the difficulty getting the surfaces at the same height. I think if I clamp the cabinets firmly together they will behave as a single unit. As long as they are held in alignment, then if the floor is not flat it will act as any other bench on an uneven floor (meaning I may need to use shims or leveling feet to keep it from rocking).

I was originally going to have the entire units adjusting in height... but the more I think about it, the easier solution may be to have the tops adjustable, and the cabinets and bases fixed. With this approach I can use popular height adjustment solutions.... like https://www.popularwoodworking.com/p...ssembly-table/ or https://www.thewoodwhisperer.com/vie...ssembly-table/

[Jim Becker]

Well, in a sense, the Adjust-A-Bench product I use is the equivalent of cabinets under with adjustability up top. I don't personally have a cabinet under mine...just a shelf...but originally intended to do a cabinet down there for my hand tools years ago. So your plan to do storage and then work out adjustable height surfaces above makes perfect sense.

[Carl Beckett]

For some reason Joe this still sticks in my mind.... guess I like puzzles.

Was thinking all you really need is a lip that would ramp the top surface up so it would be at the same plane, as you press them together. Sounds like you need a fairly big range of misalignment to accommodate. So I was thinking a tapered strip attached to the bottom edge, which could stick out 1-2 inches to provide the guidance. Since you dont necessarily know which piece is highest, you could alternate sides that have the lip, so it becomes interlocking fingers. But is really just pieces screwed to the underside. ( I have seen something common that goes together like this but my brain isnt working so not remember it at the moment...)

You still have to accommodate the uneven floor but sounds like you had a strategy for that.

I do have a table that has nested pieces, where a rail gets pulled out when expanding. This way all pieces sit on the same rail (so the top is level). The rails slide back in (and drop down) when its nested. If you were clever there might be a way to make pullout rails that span multiple sections, then the top simply sits on these. But they push back when not in use. (actually I have another table that is sliding dovetails that expand out, thus creating the surface for the leaves and top to sit on).

[Dan Rude]

You might try Alan Schaffter's "Adjustable bench design", or there is one I have been intrigued with called a "Jack Bench" by Charlie Kocourek. He uses a Scissor Jack and a Motorcycle Jack for the adjust ability. The concept of a puzzle bench may work for me in my small shop. Dan