Center join

[tango]

Hello all

 

How did the old masters make your center join?

 

What tools?

 

Did they reinforced the glue?

 

I saw somebody don't calmp the half plates ¿Did they?

 

Thaks in advance

Tango

[robertdo]

Most likely with a plane well sharpened and honed, and hide glue. Given that woodworkers can make perfectly matching center joints simply holding the plane in their hands (I still can't believe they can do that) I suppose violin makers of that time were trained to do the same.

[Peter K-G]

There is an advantage to clamp the halves together and plane both at the same time, it does not matter if the planed surface is slanted the underside will still be flat.The disadvantage is that you need to have skills and a long plane. I don't have that skill

 

[DarylG]

There is an advantage to clamp the halves together and plane both at the same time, it does not matter if the planed surface is slanted the underside will still be flat.The disadvantage is that you need to have skills and a long plane. 

 

Another disadvantage is that the center joint will be not be straight once the arching is carved.

[Craig Tucker]

I have always used a 22" joining plane, and slid the wood past it in order to get absolutely flat straight joining surfaces.

 

The advantage for me has always been that if you can get the plane sharp enough - gluing the plates together can be done by simply putting one half plate, joining face up in the vice, putting hot fresh hide glue on the  joining surfaces - and then rub joining the free plate half to the plate half in the vice.

 

A seamless join can be accomplished easily and without any clamping.

 

[MikeC]

There is an advantage to clamp the halves together and plane both at the same time, it does not matter if the planed surface is slanted the underside will still be flat.The disadvantage is that you need to have skills and a long plane. I don't have that skill

 

Join.JPG

That's an idea I had also,  simple geometry congruent angles.  But how would you clamp it in a vise?   The real planed surface would not be slanted to that degree, it would be so slight that any curve in the center join would probably not be noticeable. 

[Craig Tucker]

 

 How did the old masters make your center join?

 

I saw somebody don't calmp the half plates ¿Did they?

 

 

Hey Tango,

I do not believe that such information as this was passed down to us from the "old masters".

I believe that you're stuck deciding for yourself how to do this job, and finding out simply by doing it, what methods work best for you.

[theknowle]

 

 

A seamless join can be accomplished easily and without any clamping.

 

 

Even with cellos?

 

 

[Craig Tucker]

"Even with cellos"?

 

 

That's a good question.

I've only made violins.

 

I would guess that cellos are a completely different animal.

Anyone?

[christian bayon]

 

 

 

A seamless join can be accomplished easily and without any clamping.

 

 

Even with cellos?

 

 

 

Yes, it´s the Mirecourt tradition.

[robertdo]

But I guess it takes 2 person to rub the joint?

[Christopher Jacoby]

There is an advantage to clamp the halves together and plane both at the same time, it does not matter if the planed surface is slanted the underside will still be flat.The disadvantage is that you need to have skills and a long plane. I don't have that skill

 

Join.JPG

If it's not square, your joint gets off center as you arch it. Not the end of the world, but sloppy.

 

To the OP, I have joined plates with no clamps. Stressful. Got some beautiful JET bar clamps this year I really like.

[Will L]

The only joint I ever had open was one I clamped.  I've had great luck with the rub joint, so-far. KNOCK ON WOOD! 

[robertdo]

Rubbing and no clamp is ok and easy for the top spruce, but is it the same for the back maple?

[Don Noon]

I believe that I clamped the plates for my first few instruments, but now I only do rub joints, both top and back.  It works well.

 

I plane each half individually, to get a 90 degree angle to the base surface, then clamp the two together for the final finishing pass.  You'd have to be a total klutz to make a joint so skewed as to show an arc after carving the arch.

 

I also cheat, using power jointer.  But then I chalk up a surface plate and chalk fit the joining surface to that (using a scraper) to be sure it is dead flat.

[Peter K-G]

I'm a little surprised that the method I showed is not generally used amongst makers here. I have always thought that this is the old school way of doing joints.

[Craig Tucker]

Rubbing and no clamp is ok and easy for the top spruce, but is it the same for the back maple?

 

For me it is the same. Top and back wood. If they're flat, I can rub join the plates.

 

Others clamp every time and every piece. It's a different method - and any way that you practice can easily be found to work well.

In the past I have used clamps also. With clamps, what I found is you have to be careful not to ever starve the join by clamping too tightly. Other than that it has several things that must also be done correctly and in order - just like rub joining.

[Craig Tucker]

I'm a little surprised that the method I showed is not generally used amongst makers here. I have always thought that this is the old school way of doing joints.

 Well Peter,

 

I will say that the method where you plane the plates individually, and flat, does have several things about it that make it easier for me than planing both plate surfaces at a time and with a floating plane.

 

I'm not sure if the way you're showing is old school or not. But I would assume that if you become proficient at it, it is as applicable and workable as any other method that one can become proficient at.

 

I'm thinking that the idea here is that there are various different ways that plate joining may be accomplished well. If you wind up with a light tight, permanent strong bond - the exact method used is almost incidental.

[Peter K-G]

 Well Peter,

 

I will say that the method where you plane the plates individually, and flat, does have several things about it that make it easier for me than planing both plate surfaces at a time and with a floating plane.

 

I'm not sure if the way you're showing is old school or not. But I would assume that if you become proficient at it, it is as applicable and workable as any other method that one can become proficient at.

 

I'm thinking that the idea here is that there are various different ways that plate joining may be accomplished well. If you wind up with a light tight, permanent strong bond - the exact method used is almost incidental.

 

 

Yes, I'm going to make a joining table for my next projects, because I did not get perfect joints with my ongoing violin.

 

It's not my own ideas, I think I have learned it from a Swedish maker (Book), Uno Kallin 1928-2006 RIP,  but i can't remember. I have also seen a senior maker do this with a wooden rubank. I find the method quite elegant.Three or four steady strokes with a long rubank - That's it. I would like to master this.

[robertdo]

Even without the consideration about the center joint moving if both plates are planed at the same time, I can imagine planing a 5cm thick spruce piece of wood along the length, but a 5cm thick maple one seems pretty hard job, no?

[Carl Stross]

Even without the consideration about the center joint moving if both plates are planed at the same time, I can imagine planing a 5cm thick spruce piece of wood along the length, but a 5cm thick maple one seems pretty hard job, no?

 

Good point.

[fiddlecollector]

Even without the consideration about the center joint moving if both plates are planed at the same time, I can imagine planing a 5cm thick spruce piece of wood along the length, but a 5cm thick maple one seems pretty hard job, no?

I used to use the method i also used to clamp when gluing  . The problem with the back to back method is that you have to get the bottom surface perfectly flat first  (i prefer to flatten properly after jointing) otherwise when you have planed and then take it out of the vice the joint has usually moved.

Yes it is more hard work to plane the maple depending how thick your two halves are. If i remember Heron-Allen mentions it.

I use a rubbed joint most of the time apart from on cellos where i lightly clamp.

I`m surprised that the rubbed joint is supposed to be the method Mirecourt makers used ,as ive lost count of the number of Mirecourt violins ive had that have split down the centre joints. I havent had one split when ive used a rubbed joint.

[Christopher Jacoby]

Peter, I join my plates that way pretty often. I was just just saying that it is important to keep the joining angle square to the flat bottoms, so that your center joint stays in the center.

[Melvin Goldsmith]

If you are a moderately skilled wood worker the joining of the plates should be a very simple elementary procedure. Already in this thread I see a basic misunderstanding of basic wood working.....

If the extremely simple procedure of joining two compatible pieces of wood with a plane and some hot glue is difficult for some....what are we to make of their higher flung theories?

[Peter K-G]

If you are a moderately skilled wood worker the joining of the plates should be a very simple elementary procedure. Already in this thread I see a basic misunderstanding of basic wood working 

 

Please tell!