Dealing with unhelpful stresses in wood

[CelticRambler]

Are you sure he's French? Are you sure he's not American?

It seems to me like the kind of snake oil 'solution' I'd expect to see from Jonathan Katz-Moses, the woodworker I dislike more than any other, because he's so completely full of himself and his own BS.

Now that you mention it, I could well believe that the French lad is cut from the same cloth as JKM.

Maybe the genius with the pair of planks full of holes is going to use those holes with some big dowels to join the boards together again after (overkill, but a perfectly good way to do it, working the same way dominos/biscuits/normal-people-dowels would work for alignment), and the whole rubbish about disrupting longitudinal fibres and all that stuff is because he's overthinking it and overselling it to his audience, for whatever his reasons are.

I'm in a bad mood tonight. This didn't help.

Oh, no - he used classical dominos to re-join the two pieces later on, and added another slab, different wood, to make the table even wider ... come to think of it, I don't think he did the big transverse holes thing on that one. Hmmm ...

Theoretically speaking, it makes sense just from the visual of the holes in the planks, considering I have not watched the full video.
By drilling the holes if they are nearly full width across the boards, then I can understand the logic. The board is no longer a full length board with al the stresses that it would carry. Its now effectively a shorter segmented length board, between the holes. Smart old frenchie.

Okay, so maybe there's some value in the idea. I think he might have made reference to an ancient technique used in the making of monastic refectory tables, but I dislike his style of presentation so much, I'm not to going re-watch the video. Oh, and being typically French, he blathered on about what he wasn't doing so much that he had to spread the whole build over three videos. Next time I'm poking around a mediaeval monastery, I'll see if there's a big old table I can examine.

[kadman]

His logic makes perfect sense, and breaking continual wood fibres by machining grooves and cuts in them to reduce movement is done en masse in the wood production industry.

If you have any doubts on that just look at the back of any solid timber floorboard in any hardware store and you will see grooves to restrict movement.
The best joinery products now are produced with laminated sections to control movement. Even when thick sections are readily available. Even if you pick the straightest 3" thick plank, and reduce it by thicknessing machinery, it will deviate from the perfect straight plank you had at the outset due to stresses relieved during machining.

When I was in charge of producing cutting lists for a large joinery, all sections for door stiles were from laminated plank sections, and book matched to assure one plank cancelled out the other in stress control. Then an application of adhesive cured with high frequency drier ovens gave a perfectly straight piece.

[CelticRambler]

If you have any doubts on that just look at the back of any solid timber floorboard in any hardware store and you will see grooves to restrict movement.

Ahhhh. Is that what that is? I have taken notice of those grooves, but thought they might have been there to provide extra purchase if the boards were being glued to a solid floor rather than nailed.

I'm familliar with the concept of laminating sections that have been rotated to provide dimensional stability for large work surfaces (seems all the best workbench makers do it! ). That's always been explained, though, as a way of avoiding transverse warping; most build-it videos dismiss longitudinal change as not something to worry about ... but then they generally keep their table tops to about 2m. YerMan's is 7, which is what I'd want too.

[kadman]

And if his boreholes are well into the timber, then he has mitigated his problem of dealing with a 7 metre length, as the timber length is now hole to hole distance.

Are the holes full depth as i have not seen the video. the last video I watched that you recommended was narrated by some bloody frenchman with a strange language.

Good god man I speaketh with a dialect formulated within the sound of bow bells............cor blimey mate dontcha know, cor luvvaduck.