Folding Top Table

[fignewton]

My sister is opening a quilting/embroidery/sewing store and wants about 16 dual-purpose tables.  She wants a sturdy table to set the machines on for students.  She also has craft guilds that want to meet in her store a couple of times a week, so needs larger table surface area for their meetings.  And she wants to be able to roll them all back to an area where they won't take up as much room when not needed.  I had seen a cool table at Costco and liked the design, so I adapted it and this is the prototype I built for her.
Tops are ~60 x 30 cut from one 60 x 60 sheet of 19mm birch ply.  Working height is 29" on the casters.  Leg sets are 2x2s of ash, and I used ash for the apron, stretcher, and diagonals.  All planed to true 4/4. Used 10mm dominoes for the leg sets and 8mm for the apron, etc.  Base unit leg set bolts through the apron with 3/8 countersunk bolts. Sourced the stainless .070 piano hinges from McMaster-Carr (expensive!) 3" for the legs and 1.5" for the top.  Tops are edged with ash, and it rolls on 6 2.5" casters I got from Lowes.  Altogether, I have about $250 in this one.  Now that I have the process steps and measurements figured out, I think it will take about 9-10 hours total for each additional table.  There is some economy of scale in cutting, but many or the other steps (like the 60 screws in the top hinge) just take a fixed amount of time.  Right now they are just sanded; she will probably leave the bases natural with clear poly, but stain the tops in a reddish color. 
I think this could be scaled to be an interesting MFT asssembly table in open configuration, using a different type of leg device that would let it drop down to the floor for stability.  I've seen some Rockler sets that would prob work for that.
Was a fun project; waiting for her to come get it to see if there other design changes she'd like to make.

 

[mwildt]

Very nice! Definitely something that could be used for woodworking as well. You may be able to go cheaper on the top by using melamine or similar.

Could be a visual thing, but the last picture, where the table top is open it looks like the two tops aren't level with each other. The hinge seems to be sticking up.

Anything that fabric can catch on like the top hinge or a non rounded edge should be avoided for sure.

Perhaps a latch could couple more than one table together as well, and locking wheels.

 

[Svar]

The hinge seems to be sticking up.
Anything that fabric can catch on like the top hinge or a non rounded edge should be avoided for sure.

I thought the same thing. Different hinge type, perhaps. Look what's used on folding sewing machine tables.

 

[Michael Kellough]

Following on mwildt's concern about snagging fabric, raw wood itself will be a problem so the finishing process should include rounding all the edges and a fully sealing finish that is sanded as a final step.
You could replace the piano hinge with five Soss hinges.

 

[iamnothim]

Impressive!
Just amazing.

 

[HarveyWildes]

My wife is a quilter - she's going to see this!

 

[Billedis]

My wife is also a quilter, and I will definitely show her this.  Thank you for sharing.  Bill

 

[mike_aa]

Nice job and a well thought out design!  Thanks for sharing your ideas.

Mike A.

 

[eddomak]

Really nice design! Simple and functional (especially if the hinges are replaced with those SOSS ones)! Well done.

 

[fignewton]

Thanks for the comments all.  The tops are flush to each other.  I wondered about the mounting on the hinge, and having it stick up a little when open, but I mounted the top flush with the folded top.  Since the "19mm" ply measured out an actual 18.2mm, I will have to maybe use a 1 1/4 inch hinge.  I'm not sure if she is going to use it with quilting machines as much as with embroidery machines, and she said that on those, the work was small scale and mounted on the machine somehow. 
I've seen the Soss hinges and think they are cool, but aren't they a pain to mortise?  And how well will they work in ply (even 13-ply)? 

 

[mwildt]

Yeah, SOSS and Festool really needs to design a hinge that would work with the domino.

 

[Michael Kellough]

Thanks for the comments all.  The tops are flush to each other.  I wondered about the mounting on the hinge, and having it stick up a little when open, but I mounted the top flush with the folded top.  Since the "19mm" ply measured out an actual 18.2mm, I will have to maybe use a 1 1/4 inch hinge.  I'm not sure if she is going to use it with quilting machines as much as with embroidery machines, and she said that on those, the work was small scale and mounted on the machine somehow. 
I've seen the Soss hinges and think they are cool, but aren't they a pain to mortise?  And how well will they work in ply (even 13-ply)?

They are cool and worth taking the time to get up to speed with them.

Even with a smaller piano hinge the knuckle will (must) protrude above the surface for the the two panels to be in the same plane (if you must start from the folded together position). If you install the knuckle below surface you won't be able to open the panels much beyond 90 degrees.

Mortising for Soss hinges (the 204, 203, and 103 models suitable for this project) is simply drilling a row of 1/2" overlapping holes to the specified depth, then straighten the sides of the excavation with a chisel. Not too hard even with plywood. A Forstner bit with a more pronounced pilot is ideal so you can overlap more and straighten less. This is a good bit. In general I start in the center deeper area and work out towards the shallow but you do need to consider how the holes will overlap especially at the transition from the shallow flanks to the deeper center of the mortise.