Edge joints

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Spectric

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Hi

Well I am doing a lot more reading due to the lockdown and trying to expand woodworking knowledge when I came across edge jointing methods. Biscuits seem to be the choice for many and they say the strength is in the glue joint if the boards are properly jointed so biscuits just help alignment, all makes sense. Then dowels, now because it is a long grain to long grain joint they say dowels introduce cross grain to the joint which means if the wood shrinks the dowels can tend to push the joint apart, if this is the case then surely oblong dowels, aka Dominos would do the same or have I missed something here? What are peoples thoughts or experience?
 
If boards are well-dried, prepared on each side and straight edged, then it's possible to use any of those methods....... but it's just as easy - often quicker - to prepare the edge dead straight and use what was termed a 'rub-joint' which is exactly what it says...... you smear a coat of glue onto each edge then rub them up and down, leaving it to set in the correct positions. Using old-style animal glue this was usually enough to ensure a bond. Sometime jointing dogs pulled it together..... but that was a different technique.

Alternatively, modern glues have longer 'open' time, usually require clamping , but work just as well.
I'm writing this at a desk which was glued like that 28 years ago with PVA and still going strong.... no pegs or dowels.
However, I will use a dowel or two on very long boards simply to align the joint during glue-up and to keep the two pieces from slipping about under clamp pressure.

Along with good, dry wood, the secret of a secure joint is in the planing of the edge..... as much as the glue.
 
I have found that anything such as dowels, loose tenons etc can cause the joint to open. A rubbed joint as already mentioned is IMO far better. My own preferred method on anything that could take abuse us to spindle mould what can best described as a finger joint into each piece. It provides mechanical resilience, aligns the pieces as well as a significantly greater glue area.
 
I use a biscuit joiner and a good quality glue. Often I try to arrange my time so that I can clamp up a table top (with as many clamps as I can get on it or have!) prior to leaving my workshop for the night, and un-clamp on arrival in the morning.
i don't over tighten the clamps, but enough pressure to push the boards together. Too much clamping pressure can cause problems when you need a totally flat surface.
 
I only glue one or two joints at a time by clamping only. Run them through the planer (thicknesser) to even them up and then glue another joint or two. I don't have any issues with alignment because I flatten the boards in stages and only have to worry about one or two joints at a time. Since modern glues are strong enough to break the wood before failing there is no need to use any mechanical extras for strength. I cases of very large glue ups I might see using biscuits or dowels etc for alignment.

Pete
 
I use my no7 plane, it takes some practising but haven't found a better method of jointing two boards, clamping cauls help to distribute the pressure evenly, dowels will weaken the joint, it's unnecessary extra work imo
 
Like most of the rest said well jointed boards do not need anything other than the glue for a strong joint. The glued joint usually being stronger than the wood itself. On long board glueups alignment can be an issue and then something to help keep things in place can be a help and save some flattening afterwards. I still sometimes still use an old trick I learned at school woodwork. Tap in some panel pins part way then snip off the heads so you have a sharp point slightly proud of the wood. This prevents the glued surfaces slipping out of alignment when you clamp up. I have also heard of a light sprinkle of salt being used for this. Pete's advice on doing big glueups in batches is good and really saves heartache. Being prepared is the key to success. Do a dry run first. This gives you a time idea and also the clamps are set up at the required length. Glue, brush, rubber mallet and wet cloth ready. Nothing worse than fumbling about setting up clamps and looking for things as the glue is going off.
Regards
John
 
Hi

Well I am doing a lot more reading due to the lockdown and trying to expand woodworking knowledge when I came across edge jointing methods. Biscuits seem to be the choice for many and they say the strength is in the glue joint if the boards are properly jointed so biscuits just help alignment, all makes sense. Then dowels, now because it is a long grain to long grain joint they say dowels introduce cross grain to the joint which means if the wood shrinks the dowels can tend to push the joint apart, if this is the case then surely oblong dowels, aka Dominos would do the same or have I missed something here? What are peoples thoughts or experience?
Yes you have missed something. The mortises cut by the domino are deeper than the domino is long (you should do the same for holes drilled for dowels) so if you think that the boards could be pushed apart (personally I don’t believe they can but anyway) then just cut the domino slot on the second setting and do not glue the dominos or dowels. Problem solved.

FWIW I don’t know any regular domino users who have mentioned the supposed problem. If you want a group that has vast experience then join the “FOG” I’ve been a member for well over a decade and any problems will be posted there.

I guess the “problem” is posted by armchair warriors who have domino envy. I’ve had my domino for over a decade and never seen anything remotely like that.
 
I’ve just glued up a solid wood kitchen worktop. I dont have a panel press etc, I used the method Pete (@Inspector ) describes at the beginning, but used 6mm ply tenons which were 20mm wide in a 22mm (2x11) slot between boards to help in alignment when the top started to grow. I used a finger joint cutter on the end grain of each stave. It was 2.8m finished length and some of it was finished with a card scraper since the joints were very close in alignment. Used a hand-held router referenced from the top face and a bearing guided groover from Wealden for the job.
 
Its nice to get a perfect alignment rather than spending hours sanding and scraping the boards flush. I used to use a biscuit joiner referencing off the base but if one of the boards has a tiny bow then that will throw the alignment out. I also get a better joint straight from the table saw using a good blade rather than the planer. Freud even sell a 'Glue Line ' blade but any sharp blade will do
Now I use a set of Plano clamps and never have a problem with alignment or strength.
 
I was taught to hand plane the slightest of hollows in the centre of boards to be jointed together just enough that it isn’t noticeable once clamped. The ends of a glued up panel will dry quicker than the centre so the joint is less prone to opening up on the ends by planing the hollow In the centre.
That was the theory when I was taught it & I've never had a panel come apart at the joint even the ones I’ve done over the last 12 years reinforced with dominos more than likely because of the reason @sometimewoodworker stated.

If using pva glue adding dowels or dominos to the joint will help prevent possible movement in the panels due to pva creep, I cut down a large Oak dining table top a while ago you could feel the joints as the planks that made up the top had moved just slightly.
 
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