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Hello,

I'm looking for ideas to improve glueup of the linings I use. I laminate three layers in a form and cut the strips following Burton's tutorial here. That all works great and I love how stiff the rim is.

On the show edge of the lining I run it over a roundover bit to clean it up. It does look good but it makes clamping difficult. I get small gaps here and there no matter how well I have fit the lining to the side. It's not terrible but could be improved.

Any tips on glue up of weirdly shaped parts like that? I thought about maybe making a caul out of a spare set of lining and running it over a cove bit. The idea being to create a negative of the shaped lining. I would have to buy the bit since I don't have one, but thought I'd check here first. Maybe it's a common thing to have to glue up a surface that is rounded over in cabinet making or other woodworking areas and there is a tricky way to clamp it up?

Brad

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Just carve them in place after they're glued. A little exacto blade in a decent handle does the trick. Then clean it up with sandpaper. I don't use Burton's method but it works well for him. You could try using stronger clamps.

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Ken Franklin
clumsy yet persistent
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I put the sides in the mold first, after the frame is made and profiled.

I use three strips of linings. I add glue to the inside of the first lining and glue it to the middle lining, but not to the sides. Then I glue the the third lining to the second lining. All this is done just as if you were glueing the linings in place, or like regular linings.

At this point, you can remove the lining assembly and use a spindle, rasp, whatever, to make the visible side look nice.

Then glue to the sides.

If you only have to contend with two strips in the first glue up, it's easier to get them to conform to any irregularity in the sides.

Hope that makes sense, it's pretty late...

Both good suggestions and yes it makes sense, Ed.

After the current instrument is done I'm going to try laminated sides. When I do that I'll be gluing the sides and lining at the same time so they should mate 100% perfectly (or close), which should help.

One thing I noticed watching a bunch of youtube videos of people clamping lining - some folks clamp the lining and then push the clamp forward a bit as if to reset the pressure from the center of the lining toward the edge. That got me thinking so I spent some time clamping in various arrangements last night and noticed that if I clamp in the middle of the lining, when I release the clamp it rests back a bit and the weight of the clamp itself sort of wants to pry open the inside edge of the lining. Like the weight of the clamp is pulling it backward which tips the inside of the lining. Not sure if that's clear I might take a pic. So I'll try this method of trying to reset the pressure point of the clamp (I'm just using spring clamps) and see if that helps hold it down.

Appreciate the input!

Brad

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I find I have problems eliminating gaps when I'm trying to make the lining conform to the compound curves in a profiled guitar side because the body is taller near the waist.

To counter some of that I make my lam'd linings a little wider than finished preference. I fit them and lightly clamp them in place then draw a pencil line tracing the side profile to the back of the lining.

Rough sand the linings to the pencil line on a belt sander at an eyeballed angle to accommodate top or back radius. I don't fuss over the final width of the linings trying to get them the same width throughout. I found that to be a lost cause. Instead concentrate on the fit of the lining to the sides without trying to put the linings through a lot of contortions.

Brian R

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Brian R, Wood Mechanic
N8ZED

Good call, Brian. I do the same. After sanding to the line I run it through the bandsaw with the sanded edge against the fence to make it uniform height. That was what I thought was so brilliant in Burton's tutorial. It's uniform height and accommodates the taper.

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For back linings, I use the same template to mark the saw line that I use to mark the sides.

So I'll take the orphan side that will become the linings and use the back edge of the side template, mark a line, measure 5/8", mark a line, etc, until you've got 5 lines to make six pieces. Three are bent one way, three the other way, in a layup in the bender, strategically laid out to follow the taper of the back. Unlike binding where you jam them right up against the sides, there are two sets of three butted together pieces, but the sets are spaced out in the middle to match the taper.

Hope that makes sense...

I do something that most woodworkers might cringe at. I only use two poplar linings at about .110" thick. I wet them well just before I glue them in. The damp linings bend better to conform to a radiused back than dry linings. I use clothespins to quickly get them in place and then I replace most of the clothespins with special clamps I have made that provide much more pressure which is even across the width of the linings. Gaps are eliminated and the glue line is all but invisible.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

Ken, would be great to see a pic of what you've come up with? Here or PM is fine. I'm considering making a custom caul but perhaps a modified clamp could help.

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It's been a busy weekend Brad and Monday doesn't look much lighter. I can get you some better photos on Tuesday. Here's an old one I found. The bottom bolt goes through a hole in the outside bar. It's threaded into the inside bar. The top allen bolt is threaded through the outside bar and is stopped in a hole that's drilled partially through the inside bar. This gives me some flexibility to provide pressure where I want it. They can leave a mark in soft woods if they're tightened too much. I have some bars made from goncalo alves and some from aluminum.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

Brad—

Do you just need a clamp that is small, has parallel jaws, and is lightweight? If so, you might want to try this:

https://www.grizzly.com/products/Jorgen ... gI-2vD_BwE

I don’t laminate my linings, but I use rectangular linings rather than triangular ones, and these little clamps do great. If you try them, note that the excess part of the bar should go on the outside of the guitar everywhere but the waist, where it must be on the inside. If you do that, these clamps can be placed side by side all the way around without any interference.

small Binder clips work for me. you can get them 1/2 wide.

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