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Late night post...

Anyway, I meant laminated linings...

I find them to be so stiff in the vertical plane that they are very hard to bend 'down' at the waist when doing the back, and you end up with very short linings at the block which is unsightly.

Any tips?

I'm thinking of trying to somehow build them incorporating the radius dish...

I have an idea, but I'm curious as to what other folks do...

Try laminating a very wide sheet for linings, such as if you were laminating a side. Then you can cut along a curved line to match the curve of the eventual finished side. You will get several linings from this laminated "side".

To take full advantage, you can also pre-shape the rounded shape of the lining. First, shape the curve along the laminated "side" to match the eventual side to which it will be attached. Then use a router to route the shape of the cross section. You can work from opposite sides of the laminated sheet to get mirror images for each side. There will be some waste in the middle of the laminated sheet.

I do 3 layers and usually use poplar. I like it because it is easy to bend and manhandle in the thickness that I use. I make the strips about the same thickness of a set of sides (0.085"ish). First I put in vertical strips on the same stuff for side reinforcement the full height of the rim. I then cover the inside of the rim with masking tape carefully creasing it into the corners created by the side reinforcements (I do this so I can laminate the linings without gluing them to the rim yet). The first layer is several small sections bent and fitted between the side reinforcement strips (keep in mind they are the same thickness). I clothespin those in while I bend and fit the next layer. When fitting this second layer, I can do a fair amount of manipulation at the bend; some times a small cut in the lining will help it make the transition. I glue and clothespin the second layer to the first. I end up with a bit of buckling as the lining conforms to the curved rim but it is not too bad and can easily be clamped shut. The third layer goes on the same way. If I make another cut in the third layer to help with the bend, I don't do it in the same place. Once the three layers are dried to each other, I remove them from the rim and clean them up with a plane so they are all flush to each other on the inside (I don't worry so much about the plate side because that will get sanded to the rim when I glue the plate. Then I glue the linings to the rim. Everything is nice and stiff once the linings are dry.

I don't worry too much about tiny gaps and buckles between the layers. there is not as much as you might expect. I figure that there are probably some internal spaces that aren't clamped as well thus the glue line is not as strong but they are far fewer, smaller and stronger that the spaces in reversed kerf linings so I don't worry about it.

When I make my lining strips, I make a bunch at a time out of whatever size board I have handy (sometimes old furniture or pallets, sometimes actual lumber). If I can, I make them wide enough so that I don't really have to worry about cutting the linings to help conform to the bend. I can plane them down before installation to get them all roughly the same height. The batch I am using right now are fairly narrow. This weekend I will line the back of my current project and will probably have to make some cuts. Once it is all glued in, the rim will be plenty stiff even if I have to a couple notches in the innermost layer.

_________________
Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I did a tutorial on my method a long time ago, it is here:

viewtopic.php?f=10117&t=21455

Basically it is just like wbergman said, a solid piece the size of a side cut into the correct sized pieces. After years of doing it that way it is very quick now.
A benefit is that the plane of the gluing edge is always matched to the side. When you bend it into place it twists slightly.

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Burton
http://www.legeytinstruments.com
Brookline, MA.

I do mine pretty close to what Bryan does, only I use oak about 0.06" thick and have 5 or 6 layers. The first 3 layers are 3/8" tall, the other 2 or 3 are 1/4" tall. At that thickness it's pretty easy to get the oak (I use oak because it bends easily) to exactly follow the top of the sides. I glue them on just a little proud of the side and sand for final fit.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

Rodger, with layers that thin, you probably don't have to do much pr-bending do you? I might have to consider that. As it is, I just bend the waist and cutaway and do a real quick and dirty over bend for the bouts (all on the hot pipe). I clamp it in while it is still warm and the thin poplar takes the proper shape. It all goes faster than it sounds like. Now if I didn't have to do any bending on the pipe, I could save a few steps.

I like the idea of laminating layers as wide as a set of sides. My method grew out of never really doing the same shape twice in a row. As I work towards standardizing my shapes, I will consider this.

_________________
Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Yes, I could get away with no prebending of oak at that thickness. I do prebend, all the lining strips go on the bending form at the same time, just like I was bending a side. It doesn't take long, and it does make it easier to get the linings to conform to the sides.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

I don't always laminate my linings, but when I do, I do it Burton's way!

Flounder, if you're gonna talk like that, you're supposed to superimpose it on the dos Equis guy....

So what glue are you guys using to do your laminates?

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ELEVATE || Next Level Lutherie
http://elevatelutherie.com
&
http://ensorguitars.com

I think just about any wood glue would be up to the task. I use tite-bond original but am considering getting a white glue. sometimes I'm a bit sloppy gluing them in and end up with yellow stains on the light poplar.

_________________
Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I did imagine myself with grey beard when I wrote it!