Many are cauled, few are chosen

[rcnewcomb]

I thought I could get away with gluing the tailblock to the sides just using the form as a caul.

I was wrong.

Time to pull out the iron to heat the joint and do it over again.

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[Diane Kauffmds]

I'm sure you aren't the first person to do that. At least it can be corrected.

[Kevin Sjostrand]

What went wrong?
It should work that is how I glue my end blocks to the sides, but you wwant to put a glue barrier like wax paper between the mold and sides, and the block must be radiused to fit the mold.

[tippie53]

Yes I start them in the mold but then finish clamping outside. The mold isn't a clamping caul . I think there is a video on this https://www.youtube.com/watch?v=LrgRKKsxL-M

[rcnewcomb]

Where the sides meet wasn't a solid glue joint. The form joins at that point so there was less clamping pressure.

I also think the problem was exacerbated by the relatively low clamping pressure of the quick clamps I was using.

Since I'm still building up my shop tools I'd welcome your input on the following...

Clamps:
What clamps you prefer for gluing the neck and tail blocks to the sides?
I have a go-bar deck, but what clamps should I have for other operations, and what do you prefer?

Technique:
Do you glue both ends at the same time or do you glue one end and after it has set glue the other end?
I've also seen some people glue one side first, and after it as set they glue the other side.

[kmatsu]

Clamps:
What clamps you prefer for gluing the neck and tail blocks to the sides?
I have a go-bar deck, but what clamps should I have for other operations, and what do you prefer?

Technique:
Do you glue both ends at the same time or do you glue one end and after it has set glue the other end?
I've also seen some people glue one side first, and after it as set they glue the other side.

Randall: What I've been doing lately is to glue the tail and neck blocks with the sides outside of the mold. Here's my basic procedure:
(1) After I've bent the sides, I clamp them in the mold and use spreaders to make sure they're tight to the mold. Then I carefully mark where the sides meet the center line at the neck & tail ends. I use the bandsaw to cut a tiny bit outside my lines, and use the disc sander to sand up to the line, a little at a time, constantly checking it by putting the sides back into the mold. I want the sides to be able to sit tight in the mold, with the ends butted against each other, even without spreaders.

(2) I then mark the center lines on the neck block and on the tail block, after sanding the very slight radius on their gluing side with the belt sander. (I mark the radius on the block by tracing the mold neck and tail end shapes onto the block end, and then sand to that radius line.)

(3) I use those large plastic spring clamps (you know, the red/orange ones I had --- I like them because they're really strong) --- I glue one edge of the side right to middle of the center line. I just glue to one side of the block at a time; that way I can easily tell if anything slips out of alignment. After that one side is dry, I do the other side of the block. I size the block so it's sticking maybe 1/64"-1/32" above the soundboard edge of the side, and about 1/32"-1/16" above the back edge of the side.

I used to glue them in the mold (with waxed paper between the side & the mold), but I find it's much more accurate the way I do it now. Fewer pieces to fiddle with. Less chance of things slipping or not being in alignment, or not being a tight glue-up.

Check out this page:http://theamateurluthier.com/retirement ... ylor3.html

Also....feel free to come over or call any time you have questions or aren't sure about something!

[rcnewcomb]

Thanks John and Kathy. Both of your responses were helpful.