Torsion box for sewing console top

[johnpipe108]

I got off my duff and assembled the pieces for converting the single 3/4" top of my sewing console project to torsion-box construction. A couple weeks ago I had cut the cores from 7/8" pine scrap (FREE!! :eusa_danc, donated "firewood" from my son-in-law's sister's boyfriend who works in a furniture factory), along with the MDF flat for the bottom.

Today I finally got out the router and plunge base and traced out the machine cutout in the MDF, fine trimmed the cores where they were overlength and glued everything up. The parts were "clamped" by nailing them down with finishing nails.

Here's the assembled view from the top, with the head awaiting re-installaton.

The finished top is now about 2-3/16" thick; similar in thickness to commercial console tops, which are about 2".

John

 

[Travis Porter]

What kind of finish are you going to use? Does the thickness interfere with the sewing machine?

 

[DavidF]

My only comment would be about the use of pine for the core. You may find that expansion and shrinkage affect the flatness of the top. I know it isn't designed to be a precision surface, but it may be noticable. On the two torsion boxes I have made I have used MDF core and panels. I did use poplar on the very thin torsion box (1 1/4" total including 1/4" skins, but the thought that the small width of the core would not give me problems (3/4") just my 2d worth.

 

[johnpipe108]

My only comment would be about the use of pine for the core. You may find that expansion and shrinkage affect the flatness of the top. I know it isn't designed to be a precision surface, but it may be noticable. On the two torsion boxes I have made I have used MDF core and panels. I did use poplar on the very thin torsion box (1 1/4" total including 1/4" skins, but the thought that the small width of the core would not give me problems (3/4") just my 2d worth.

Hmm ...

I didn't have any idea about that; justjumped in and made the project. Too bad I have a habit of "git er done" without always doing adequate research. I hope it doesn't become a problem, but, oh well, it's done.

John

 

[johnpipe108]

What kind of finish are you going to use? Does the thickness interfere with the sewing machine?

I made the basic table late last year, and used Minwax Wipe On Poly finish. No finish on the MDF bottom, at least not yet (? necessary/not necessary?).

There's no reason I know of for thickness to interfere with a machine head made for console mounting (as almost all the metal heads are/were). I have a slight inconvenience of not being able to tip the head up on it's hinges, but that's because the lower front of the base doesn't clear a narrow wood support strip on the front of the cutout, and this is regardless of top thickness.

I never had that problem on my old machine head, only on this particular Singer model; unfortunately, my step-son was helping with moving and storage, and dropped the old head on the concrete, it landed on the drive wheel causing the spindle to bend and jam permanently. It was a really nice, old, basic zig-zag machine and was less troublesome than the Singer (which was the only used console-mount machine readily available when I had to quickly replace it a couple years ago).

John