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By custard
#1231404
LancsRick wrote:What is your recommended clamping approach?


You make a very good point, it doesn't matter how good your edge jointing is if the glue-up goes pear shaped!

I guess the first thing to say is that hide glue has a lot of advantages for edge jointing, and you don't even need the original hide glue that you heat up in a double boiler. Easy to use liquid hide glues, like this one,

https://www.axminster.co.uk/titebond-li ... ue-ax22595

work just as well for a rubbed joint.

The advantages are you don't need any cramps, you just put one component in your vice and apply a decent wiggly bead of liquid hide glue along it's length, rub the joint together to even out the glue and expel any excess. Soon you feel it start to "bite", then get the two components lined up exactly as you want and leave them in the vice for a few minutes. After that you can take them out of the vice and prop them up in an out of the way location for a couple of hours while the glue cures. It's absolutely 100% strong enough for virtually any furniture making application, squeeze out clean up is dead easy, and if by any chance you're unhappy with the result it's fairly straightforward to undo the glue joint with a damp rag and a steam iron, fix the problem and try again.

Staying with the notion of using your vice as a glue-up aid, there's a trick that's often used in professional workshops for lightly stressed, edge-jointed components, such as panels for frame and panel work, or small tops for occasional tables.

Step one is to place one component off-centre in your vice,
Glue-Up-Panel-01.jpg


Step two is to apply the glue then place the second component on top, like this,
Glue-Up-Panel-02.jpg


Then finally you use one, lightweight cramp in the centre, like this,
Glue-Up-Panel-03.jpg


Your edge jointing needs to be pretty accurate, with a minute hollow to give you a slightly "sprung" joint, and you also have to have the knack of tightening up a cramp without twisting the components out of line. But if you can do all that, then this is a super fast method. With a fast setting glue like Titebond 1, you can store the glued and cramped components in an out of the way location for 30-40 minutes, and as long as you're careful they'll then be ready for the next stage in your build.

But if you want to do the full monty glue-up then here's how I go about the job. I'm not saying this the best or only way, but it is an approach that consistently delivers first class results for me.

The first thing is that I always use bearers rather than resting the workpiece direct on the sash cramps.
Glue-Up,-Edge-Joint-01.jpg


These bearers are either waxed or covered in parcel tape to prevent the glue sticking to them, and they bring two huge advantages. Firstly you can shim them so the bearers form a totally flat plane for the work to sit on, which prevents any twist or wind being introduced at the glue-up stage. Secondly they're sized so they're a bit deeper than the "spines" of your sash cramps. This keeps the work floating above the sash cramps, which makes glue squeeze out removal much easier, plus it also prevents the risk of "iron stain", which is what happens when a timber like Oak, high in tannins, touches steel in the presence of moisture (which most glues will provide plenty of!).

You then do a dry glue-up. You always do a dry glue-up, no matter how experienced you are and how many times you've done the job, this final dress rehearsal is the last chance to check you've everything you need, it's all working properly, and the workpiece lines up exactly as you need.
Glue-Up,-Edge-Joint-02.jpg


Next step is to apply a thin layer of glue to both components to ensure they're thoroughly "wetted out"
Glue-Up,-Edge-Joint-06.jpg


You then apply cramp pressure, starting in the centre and working out, checking for a bead of squeeze out all the way along as you go,
Glue-Up,-Edge-Joint-07.jpg


Now, if you want, you can carefully lift the glued-up assembly off the bearers and check for an even bead of squeeze out underneath,
Glue-Up,-Edge-Joint-08.jpg


And the gaps left by the carefully sized bearers mean you have full access for cleaning up squeeze out,
Glue-Up,-Edge-Joint-09.jpg


With all the squeeze out removed (on critical jobs I usually do three repetitions of scrubbing with clean, boiling water) you can set the piece back down and do a final check for straight and flat,
Glue-Up,-Edge-Joint-03.jpg


Finally, a couple of little wrinkles that may be useful.

Sash cramps rarely apply pressure at exactly the angle you expect. The "shoes" sometimes angle back, or the "spine" bends upwards under pressure. Having cramps top and bottom helps. But sometimes you'll need cramping blocks on the outer edges with a "D" shaped profile, this profile automatically adjusts for out of true sash cramps, and delivers the pressure perpendicular to the joint.

Another point is that I hardly ever use biscuits, dowels, splines, or dowels. I don't believe they add any useful strength and they bring with them a load of hassles. The exception might be if I'm working single handed on a really big job. Then I might use one or at the very most two biscuits, inserted dry, in the centre of the workpiece, and this is purely to assist in alignment. If you've edge jointed properly you really don't need anything else.
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By LancsRick
#1231409
As ever custard the quality of your guidance is brilliant, thank you. Sounds like I may be limiting myself to the final option at present (or second option) as I'm using pva.

I also have clamp envy..
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By Sheffield Tony
#1231424
custard wrote:Secondly they're sized so they're a bit deeper than the "spines" of your sash cramps. This keeps the work floating above the sash cramps, which makes glue squeeze out removal much easier, plus it also prevents the risk of "iron stain", which is what happens when a timber like Oak, high in tannins, touches steel in the presence of moisture (which most glues will provide plenty of!).


Good tip, found this the hard way glueing up some oak door panels. All that effort to get a super good joint, and it had thin black dashes where the glue touched the clamps #-o
By Duncan A
#1232053
Just found this thread. Absolutely superb Custard, many, many thanks.
I don't make furniture or anything of that sort, but it is nevertheless useful to know what I'm supposed to be doing when edge joining. You must have spent a lot of time putting this post together and, as others have said, the result is worthy of inclusion in a book.
Since it's not a book, do you have a favourite charity to which contributions could be made?
Duncan
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By custard
#1232136
You're welcome Duncan. Despite there being no end of YouTube videos I'm conscious that a lot of the critical information needed to successfully make furniture is either missing or is just plain wrong. So I try and do my bit to lay out the cabinet making practises that work for me. I'm not saying these are the only way or even the best way, but they're methods that I've found deliver good quality results.
By SammyQ
#1232712
Solo Cramps are a good cramp, cheap and with plenty of workshop applications, but they have a tendency to let go under vibration.


Sheesh...honest? I've done almost all my amateur routing with them and never had a problem. I guess, Fate is waiting for that irreplaceable component to teach me this one. :shock:

Sam
By johnnyb
#1233062
This technique was one I saw in the boys workshop companion. It was my favourite book as a child! I can't remember ever trying it though!
One technique not mentioned is to attach a fence to your plane to shoot 90 degree joints. Popular in technical schools in the 50s apparently. Actually better for planing angled edges though.
Superb post custard really practical and detailed.
By Docile
#1235294
Excellent contribution, Custard. Thanks for taking the time and effort. Loads of useful learning points.
By large red
#1245689
Thanks Custard, that was a really clear, informative and interesting . I normally plane and get good results, even if the boards do occasionally get quite a bit smaller!
I have used a simillar router method and while it was successful I found it to be awkward and surprisingly slow. I must get around to making a template up for the router table with toggle clamps to hold the work.
By will_s87
#1246723
thanks for taking the time to write this up.

you mention using a D profile on the sash clamps to provide clamping pressure perpendicular to work piece, I've had some success with using dowels.

Will
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By El Barto
#1246747
This is such a great topic so thanks Custard. My two pence to the process is that quality cramps really make such a difference to what is an already stressful process, especially for a newcomer.

When I built my workbench and had to laminate the top, I bought cheap aluminium sash cramps a la Paul Sellers and followed his advice about reinforcing them with wooden strips. In hindsight I would splash out for high or higher quality cramps if I could as the cheap ones are terrible. The heads frequently bind to the bar and the little rubber grommets on the handles fall off all the time - I found myself faffing about with making them work correctly instead of focussing on the glue up. So I think that's probably an area of the beginner woodworker's kit list that is often overlooked. I used them for a glue up tonight and they were utterly useless and so back into the corner they'll go.

However I did get a couple of these the other day and they have been very good and also reasonably priced: https://www.axminster.co.uk/axminster-t ... p-ax945578

Thanks again Custard.
By Ed Turtle
#1276716
custard wrote:
Sash cramps rarely apply pressure at exactly the angle you expect. The "shoes" sometimes angle back, or the "spine" bends upwards under pressure. Having cramps top and bottom helps. But sometimes you'll need cramping blocks on the outer edges with a "D" shaped profile, this profile automatically adjusts for out of true sash cramps, and delivers the pressure perpendicular to the joint.


I'm sorry if this is obvious, but to me i cant quite work out how this works! Could you explain further please?

Thanks
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By custard
#1276722
I hope this sketch explains.

Sash-Cramps,-D-Blocks.jpg


At the top is a sash cramp tightening up on a workpiece. The jaws of the sash cramp are splayed out (exaggerated, but most cramps are in fact slightly splayed in this direction) as a consequence they're pushing on the bottom corner of the workpiece and so making the workpiece bow upward in the middle.

At the bottom is the same arrangement, but this time with D shaped cramping blocks. These cramping blocks compensate for the splay of the jaws and prevent the workpiece bowing up in the centre.
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