Novice question for edge gluing boards

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Biblu

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Sorry if this is a stupid question but I have 5 boards (300cm x 11cm x 3cm) that I would like to join. While I've done an ok job of planing the edges, my jointing skills are somewhat lacking and my patience lacking even more, so I was wondering if there was a good reason for not edge gluing boards one by one?

My thought process was that one by one there would be less force opposing the clamps, as they're fighting against one edge rather than four, leading to a better mating of the edges. As well as that, two boards are more manageable than 5 in terms of aligning and clamping up etc.

IMG_4431.jpg
 
not to sure what's going on in the photo. are you making shelves so putting strips on the edge or a table top so joining five boards together?
 
not an expert by far, but I believe the common wisdom for edge gluing multiple boards and only doing a few at a time ( i.e you want 6 boards but do 3 at a time ) is either down to available clamps , as in how many you have and width capacity but also down to the size of your planer. So lets say you want to surface plane after glue up but your planer is only 16" wide then you do two sections that fit and then do a final glue up. I could be wrong but that was my understanding.
 
Not an expert, so beware! But my own experience is that when gluing up a large top/panel, the assembly table and clamps act as a reference to ensure it is level and not twisted. My concern with doing it board by board is any error in the first glue-up is 'baked in' and likely get worse and worse as you add more boards.

One option to help make the glue up easier is to get a biscuit jointer, the biscuits will align the boards with each other.

A 3m long top is a big undertaking and those are long edges, good luck and would love to see some more photos, looks like a great project.
 
Also alternate the clamps over and under the boards being clamped.
This helps to reduce them collectively cupping.
 
not to sure what's going on in the photo. are you making shelves so putting strips on the edge or a table top so joining five boards together?

It's a table (office desk) top, so joining five boards together. The photo was just the first edge that I had started/done (depending on how much more patience I have with it), and to check quickly how it looked when clamped together. I like to take a photo before I start edging, and another at the end of the day. The one at the start of the day had a nice gap running along the middle so I find it helps to keep me motivated to be able to see the before/after when I sit down with a beer in the evening :)
 
It's a table (office desk) top, so joining five boards together. The photo was just the first edge that I had started/done (depending on how much more patience I have with it), and to check quickly how it looked when clamped together. I like to take a photo before I start edging, and another at the end of the day. The one at the start of the day had a nice gap running along the middle so I find it helps to keep me motivated to be able to see the before/after when I sit down with a beer in the evening :)

Ah, now I think I get it, like @johnnyb I was confused by the photo. It's two boards not one, and the strips of wood on the outside are to prevent clamp damage?
 
Much easier one by one. Join first pair, join second pair, join 5th board to one of the pairs, join 3 to 2
 
Not an expert, so beware! But my own experience is that when gluing up a large top/panel, the assembly table and clamps act as a reference to ensure it is level and not twisted. My concern with doing it board by board is any error in the first glue-up is 'baked in' and likely get worse and worse as you add more boards.

One option to help make the glue up easier is to get a biscuit jointer, the biscuits will align the boards with each other.

A 3m long top is a big undertaking and those are long edges, good luck and would love to see some more photos, looks like a great project.

Thanks Fitzroy, I also wondered about cumulating the errors rather than averaging them out with one glu-up.

I do have a biscuit jointer so will definitely be using that.

It's a very very basic desk, one top and two sides, made from strips of oak glued up. It started over a year ago so you might be waiting a while before more photos 🤦‍♂️😁 It's my first furniture project and I grossly underestimated the difficulty of working with 300cm x 25cm lengths of sawn timber, plus my planer died...but I least I learnt (somewhat) to hand plane!

forgot to add if you are worried use clamping cauls as those and the underside of your clamps should be enough to keep the boards all ;level .
https://www.finewoodworking.com/2011/03/08/clamping-cauls-the-secret-to-great-glue-ups

I was planning on using cauls (though I didnt know thats what they're called, thanks). I was planning on planing some slightly convex ones - do you better experience with those or not think they're worth the effort? The total width of the panel would be ~70cm
 
Ah, now I think I get it, like @johnnyb I was confused by the photo. It's two boards not one, and the strips of wood on the outside are to prevent clamp damage?

haha 🙂, yea, sorry for the confusing photo, but I'm quietly very pleased with myself that it appeared as one board! Photos can be deceiving 😁

Much easier one by one. Join first pair, join second pair, join 5th board to one of the pairs, join 3 to 2

Thanks, are there any downsides to doing it this way? For example, I wondered if that because the last join of 3 to 2 would be ~25cm to ~35cm, then both of those would be quite rigid and struggle to hide any imperfections in my edging?
 
haha 🙂, yea, sorry for the confusing photo, but I'm quietly very pleased with myself that it appeared as one board! Photos can be deceiving 😁



Thanks, are there any downsides to doing it this way? For example, I wondered if that because the last join of 3 to 2 would be ~25cm to ~35cm, then both of those would be quite rigid and struggle to hide any imperfections in my edging?
No you would match them up and have a chance to remedy any imperfections.
In fact do that for each join. 1st board edge up in vice, balance 2nd board in it, check that it sits square (with a short straight edge) and check that it sits tight. Same as you prepare to glue up for each joint, make sure the boards fit nicely.
They need to be tight fit at the ends as that's where they start opening up, so a very slight gap in the middle could be good i.e the faintest hollow along length of one or both boards.
Except for this faintest hollow you don't want to be reliant on very tight clamping to keep edges together as the wood will fight back and could start a split, either at the join or somewhere else, days or years later.
 
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Thanks Fitzroy, I also wondered about cumulating the errors rather than averaging them out with one glu-up.

I do have a biscuit jointer so will definitely be using that.

It's a very very basic desk, one top and two sides, made from strips of oak glued up. It started over a year ago so you might be waiting a while before more photos 🤦‍♂️😁 It's my first furniture project and I grossly underestimated the difficulty of working with 300cm x 25cm lengths of sawn timber, plus my planer died...but I least I learnt (somewhat) to hand plane!



I was planning on using cauls (though I didnt know thats what they're called, thanks). I was planning on planing some slightly convex ones - do you better experience with those or not think they're worth the effort? The total width of the panel would be ~70cm

no need to over complicate things n that width . Have found in the past that a combination of biscuits ( for alignment only remember they don’t add strength) good cabinet clamps I.e that have a flatsurface so not pipe clamps and some cauls and you will be golden
 
Along with above advice if getting a good square edge is difficult there is alternate method, though not to everyone's taste. Fold two boards together so one face side is facing the ceiling the other face facing the floor, use your straightest board as a guide and use a circular saw trim a few mill of the edges. Then 'fold' back when cut. A 8" circular saw is required at a minimum along with a decent blade 40 tooth plus blade and no hesitation when cutting. Set the blade so that one tooth is just below the board, around 62mm. At 300cm another pair hands would be useful to help move the power lead, unless it cordless, but in any case would just be useful to have a helper.
 
...remedy any imperfections.

I think that's where my woodwork skills are left lacking 😁

...balance 2nd board in it, check that it sits square (with a short straight edge) and check that it sits tight.

This is genius, I was unclamping the piece I was working on everytime! This sounds much easier, thanks.

Just a thought Biblu, 3mtrs, is that all for the top? You aren’t going to cut the ends off to form the ends are you?

Also it’s important to "cup and bridge " ie alternate the boards, which I’m not sure you have in that photo. Ian

No, it'll be cut down to ~2.4m for the top. I figured it was better to do the joining beforehand and make the cross cut last? Maybe I should cut them down to 2.5m now though to make my life a little easier in both the edging, and I guess the final cross cut will be easier taking off a few cm rather than 30?

The ends are made in the same way, from the same wood, and are already edged. As they're only ~80cm long I found the edging more managable and even when not clamped together they sit close enough that I can't fit a thick piece of paper between them, so I think they're ready to be glued.

I had read about alternating the boards, but admit I had forgotten and hadn't planned to. Four of the five lengths are cut from two pieces orginally (so I could fit them in my thicknesser) and I've put those two pieces back together and laid them all out purely on an aesthetic basis of passing the wife-test. I've watched lots of videos where people don't seem to do this, so is it a critical step that means guarenteed failure without following, or is it just good practice?
 
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It’s an important thing to do depending on how the boards were cut from the tree, just cutting the boards up and then gluing them back the same way is really not the way to go. Look at the end grain and follow this badly drawn sketch. Ian

74241EED-6A2C-46D1-839A-BCBDFA1AA2BD.jpeg
 
The other consideration is grain direction. If you end up having to plane the top and two boards have grain running alternate directions it’s a real pain.
 
This may be a heresy - so others can comment on the wisdom/feasibilty - but given the dimensions would it be possible to use kitchen worktop connector bolts.

Done on the underside they would not show if left in place, allows the wood lengths to be accurately aligned, trial clamping before gluing, bolts tightened gradually before glue dries.
 
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