Adjustable height workbench / assembly table

[Duane McGuire]

In my early years of woodworking and cabinet building, I spent a lot of time assembling things on the floor. I'd never worked in a professional shop, and I didn't have the room for an assembly table. When I went to work in the ML Bigelow organ shop, our primary assembly table was a dead flat surface of 10' X 5'. What a difference! With a dead flat surface, assembling cabinets to square is so much easier. With the work off the floor, assembly requires a lot less expressive language.

For my new shop, and especially for piano action regulation I wanted a nice assembly table, but also I wanted it to be adjustable in height. The pictures below show my creation.

The adjustable height will allow me to do action regulation work comfortably in both sitting and standing positions. The table top is 3' X 5' and the surface is dead flat within 0.5 mm. The flat table was constructed in as a torsion box, pretty much as described by the "Wood Whisperer" in this article. It features an oak apron which sits 1/4" proud of the table top. This allows a 1/4" piece of masonite to lay inside the apron. When the work surface becomes marred, it can easily be replaced. That's a nice feature!

I created the adjustable height mechanism by adapting an adjustable height cart sold by Harbor Freight. The base was built to fit the cart. I removed the wheels and handle from the cart and fitted it to the base. The table top is fastened with lag screws and plenty of construction adhesive. There is a small amount of side play in the mechanism, so the table wouldn't be suitable for much pounding and hammering, but that's not what I had in mind. At all heights it is very stable vertically. The table has plenty of mass (about 300 pounds), which enhances its stability.




Minimum working height of the table is 24 inches.


Maximum working height of the table is 48 inches.

[Richard Gibson]

I really like this Duane. I've been thinking of trying something like this and you did it! Thanks for sharing.

You say there is some side play and "not suitable for much hammering or ponding". Can you explain that a little further? When I assemble, I do lots of hammering but not "heavy". I put small items together with finish nails in pilot holes so I don't have to beat it to death. Would this table handle that kind of hammering?

[Duane McGuire]

When I assemble, I do lots of hammering but not "heavy". I put small items together with finish nails in pilot holes so I don't have to beat it to death. Would this table handle that kind of hammering?

Sure. Not a problem. Just an observation. When this table is at a 40" work height, and I give a solid horizontal shove to one corner, the table top moves about 10 mm. This is due to the play in the scissors jack mechanism. With some fussing, this play could be reduced, but by the nature of the mechanism, it will not be eliminated. I've thought that a nylon strip insert in the wheel ways at that top of the scissors jack would limit the play and still provide a smooth action. But that detail will probably not be implemented. It is going to be great, just the way it is.

By the way, vertically, at the left side (fixed side of the jack), more than 150 pounds of downward force is required to get any jiggle in the mechanism. At the right side (free side of the mechanism) somewhat less than 50 pounds of downward force will jiggle the mechanism. All of this is academic, though. With a normal balanced load (workpiece) this adjustable table is going to do its job like a dream. (Even though I'm analytical, I'm excited!)

[Sam Layton]

Duane, that is a great assembly table. I have the same questions as Richard. Thanks for sharing.

Sam

[Rick Moyer]

Does it sag to the "free" end? It looks like it in the pic. I suspect you could add some swing down legs to that end to help support everything if needed.

[Duane McGuire]

Does it sag to the "free" end? It looks like it in the pic. I suspect you could add some swing down legs to that end to help support everything if needed.

Hadn't noticed any. Now that you've asked, I'll have to get out to the shop and measure. Looking at the photo of full extension height, it does appear to be lower on the free end compared to the radial arm saw table in the background. Curiosity will reveal an answer!

[Duane McGuire]

Does it sag to the "free" end? It looks like it in the pic. I suspect you could add some swing down legs to that end to help support everything if needed.

I measured and at the full extension the left end (fixed) is 48-1/2" and the right end (free) is 48". There is a bit of a catch in the mechanism in the last 2 inches of extension. Two inches lower at 46" both ends measure the same within 1/16".

[John Petsche]

great lift cart (table idea). Thanks for posting pics.

[Ben Martin]

Duane,

Are you still using this table? How about an update on how it is working out for you!

Ben

[Bill Edwards(2)]

Duane,

Are you still using this table? How about an update on how it is working out for you!

Ben

His profile doesn't show any activity for the last year.

[Jim Andrew]

Has anyone built an adjustable height table without buying the mechanism? I was thinking of a way to build one, of course I wouldn't expect it to work as nicely without hydraulics, but think I could get it to work. Really don't need quite as much height adjustment. Was thinking of about 30" maximum height and dropping to about 18". Maybe using a crank and a cable, with legs which angle, one end bolted and the other using rollers.

[Jim Neeley]

Jim,

Check out jack dash bench dot com. I ordered a set of their plans, intending to make a workbench, but decided to go with adjust-a-bench instead, as it left me room for storage.

Jim

[Ben Martin]

His profile doesn't show any activity for the last year.

Bummer, never thought to check that...

[Calvin Crutchfield]

That's interesting. While on a very rare visit to HF this past week I was looking at these mechanisms and thinking to myself if they would be suitable for a table like this. Thanks Duane, I think I will craft one with the aid of these pictures.