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Though I haven't use inside supports when gluing the top and back to the sides, after seeing that some use the supports, I thought I would do it the next time around which should be very shortly. But before that I thought I'd share the design with the OLF. Not wanting a whole redesign of my current support, which was not orginally designed to be disassembled and taken out through the sound hole, I came up with the following. I simply cut the thread rods in half and insert the middle section into a 3/8" - 1/16" thickness brass tube for support.

Here's a picture of the support install before glue-up.



A closer look.



Here are the supports disassembled.



The supports can easily be taken through the sound hole after the back and top have been glue up. One small turn on the pressure knob and the brass sleeve slips to one side and the support falls apart.



I'm not sure if anyone has done this before and I present no ownership to the idea.

I have recently added electrical tape to one half of each thread rod to simplify alignment.

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Michael Lloyd

“I was born to ignorance, yes, and lesser poverties ...
I was born to privilege that I did not see ... I didn’t know it, but my way was paved” – John Gorka

Thanks for the heads up Hesh. I gave it a try and with average size hands I can easily reach the knobs to loosen. I tried it with both a 3" and 3.5 " sound hole. As little as 1/8 of a turn is all that's needed to have the system fall apart.

I was wondering about the supports you used being at the lower and upper bouts and the reason you use this approach. At first glance it appears to be more rigid.

BTW it was your tutorials, which prompted me to post.

Thanks.

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Michael Lloyd

“I was born to ignorance, yes, and lesser poverties ...
I was born to privilege that I did not see ... I didn’t know it, but my way was paved” – John Gorka

I don't use the spreaders when I close the box. I use them while attaching the back, in the mold of course, then when that dries I flip the mold over, remove the spreaders and attach the top. I see no use for them at that point. The mold offers outside support, and the notched kerfing (if you don't cut through the sides) keeps the sides from flexing in.

Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

I have used the spreaders historically like Ron when attaching the back they stay in place and remove them before glueing the Top, however, on my last two I did try leaving them in while glueing on the Top and I liked it. Although minimal, I have seen on some woods and builds that after I removed the spreaders after the Back was glued the rims might come in slightly which you can just power through and probably not have any problems, so I am doing it just to keep everything in place during both processes then I know nothing will move beyond that point.

Mike