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G'day Colin,
                I gave a lengthy reply to this last night ,only for it to be wiped before posting 1000 curses. Don't you just hate that ?

I see the top as a more important join than the back ,so glue it first . This way,I can ensure my A frame pockets into my head block and X brace ends all fit perfectly and are cleaned up nicely . Glueing the back first is usually done for cosmetic reasons, but I have that covered too ! ( read on )

Firstly ,I ensure a perfect radius has been imparted on the rim . The (soundboard) dish is placed on the go bar deck and covered with posterboard. I place the glue round the sides lining , and hold it over the sound board at a slight angle so that the glue has not yet made contact . With my other hand I prop a go bar through the mold onto the middle of the X Brace . This brings the soundboard down to meet the dish snugly .I then lower the rim set,( still in mold ) . A few cam clamps straddled from the top of the rim set to under the deck is all that's needed . Cam clamps are a better method than go bars . They are just as quick, and don't get in the way while cleaning up any squeeze out that may be there . I have found that there only need be one go bar to hold the soundboard down to it's true radius .If there were any small irregularity on the sides radius , I'm sure the cam clamp's force would pull the join together , but I take no chances. The problem of joining the plates without this dish method is that the sound board has a certain amount of spring back after being braced and doesn't retain that perfect radius we are trying to impart . If you were to use other methods such as neoprene rope or spool clamping from the top , you are glueing down the top when it's not conforming to the radius wanted .

Glueing the back is much the same operation ,except that you now have the back dish on the deck . Place a go bar through the sound hole to bring the back plate down to meet the dish ,but place it through the rear part of the soundhole ( closest to bridge area) . This is very near the centre of the back's radius and still allows access through the soundhole to clean up any visable squeeze out .

Best regards Craig Lawrence

P.S. You'll need the long cam clamps for some areas , but that's cool, as you don't need a lot of force with the weight of the mold already doing a good job . As usual,,,, dry run first.KiwiCraig39022.815162037

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CRAIG LAWRENCE of AUSTRALIA
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Mike, the Cork caul is made from a scrap of ply I had lying around. It is designed so it can be used on My SJ, OM and L-00. I have a separate one for my size five. I've glued Top first and back first and really don't knowe which I prefer. Once I did top and Back in one step which worked but using HHG it was stressful and not worth the time saving.

I used a similar method. My stack consists of a wooden chisel box on the workbench to act as a riser, then a 24" square piece of 3/4" mdf, then the sides in the mold, then the sanding bowl. All of this is clamped with 6 to 8 clamps.

I didn't have access to the inside, but experimented with brushing LMI white glue on similar thickness scrap to get a good glue line without excessive squeeze-out.



edited for (and by) dyslexic fingers jhowell39022.9410532407

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Jim Howell
Charlotte, NC

Great thread and tips guys, thanks!