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30 January 2024 at 11:49 am #826877
Understanding Wood by R. Bruce Hoadley might perhaps be one source.
Another one is perhaps The Wood Database (available on line and in printed format)
Both discuss the main properties that govern when wood will bend and break.
Prudence, I think, calls for pointing out that two of those properties (Modulus of Rupture and Modulus of Elasticity) rest on rather widely dispersed observations. So the point values presented by these two sources should possibly be taken with some care.
There is a very good correlation between the density of a specific kind of wood and its tendency to bend under load.
26 January 2024 at 4:01 pm #826511Hi,
Didn’t give this any consideration, and of course sawed through an over-sized tail. As the photo shows, this results in a bit of asymmetry, in as much as the top of the lid there’s a half-pin, while at the bottom (and top of lower part) one finds “two meeting half-tails”.This is of course mostly aesthetics, and nobody else has ever noticed the discrepancy.
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You must be logged in to view attached files.23 January 2024 at 10:38 am #825862Two thoughts:
When hanging larger cabinets I’ve had to deal with the walls not being flat or plumb. Battens along the bottoms of the cupboards appeared as a safer and simpler alternative. Please see photo. The inset pane just shows a way to support a wide cabinet while mounting it. A rail along the top back allow for screwing the cupboard to the wall, without those screws having to take the weight of it. That also allowed for using a thinner back, flush with cupboard back – somewhat increasing the interior depth.Would starting with the pins of the dovetail joints be an idea to be considered? Marking out the pins from the tail parts could perhaps call for holding the tail parts 48″ up in the air. The second photo shows the marking out the tails on a 60″ long piece of a sideboard.
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You must be logged in to view attached files.6 January 2024 at 2:25 pm #824216For whatever it might be worth, here’s a link to the Wood Database information on Makore
7 December 2023 at 11:49 am #821390My five year experience from a workbench made from 3¾” thick glulam (spruce) is that the first 3″ of the front should have been FAS beech (usually straight and knot free).
The holdfasts have widened the dog holes enough to have an impact on the bench dogs, and securing hold downs. I repaired the holes first enlarging them, inserting pieces of oak, and then re-drilling new ¾” holes. After six months of use, the holdfasts have not had any effect on the the bench holes.
Secondly, with use and wear, the front to edge corner is no longer very sharp. The angle is still overall 90°, but too rounded over to use the edge as a fence support when planing grooves and rebates.
The part of the bench occupied by the tail wise is in beech, with no changes whatsoever.
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You must be logged in to view attached files.9 November 2023 at 8:01 pm #818610Having the complete set of LN mortice chisels, bevel edged ones, and their fishtails; and used them for a number of years: it is perhaps not totally inappropriate for me to vent an opinion – the more so as I also have experience from the chisels from R. Sorby, H. Taylor, Narex, Veritas, and some other best forgotten brands.
Though I use the mortice chisels whenever possible, it is mainly because the sides are square to the back, which makes the use of a mortice guide very beneficial; the bevel edged ones are subjected to many more hammer blows – mainly in quite dense woods – which probably seated the handles in their sockets. As LN do not offer traditional paring chisels, I think it is welcome that the short handles can be replaced with longer ones, which improve my work.
I value that these chisels come at their pre-specified dimensions. The backs are flat, obfuscating the need for fettling, and their widths within very narrow tolerances. When combined with “Tite-Mark’s” mortice gauge wheels, all mortices start at a width congruent with that of the chisel – a happy state that I usually ruin. My tools from other manufacturers, also premium ones, have significantly wider tolerances.
A2 steel is probably more brittle than O1, which maybe explain why LN recommends adding a 5 degree additional secondary bevel for better edge retention, and perhaps also to reduce the need for sharpening, though edge retention is in comparison very good. Yet, even someone as mediocre as I find sharpening the LN blades and chisels more challenging than for their 01 counterparts. Thankfully I’ve been presented with a leather wheel, which prolongs the time between visits to the sharpening stones.
One aspect – which perhaps does not aid in mortising – of LN chisels is that the bevels extend all the way to the backs, which might be of relevance when clearing out non-square corners.
26 October 2023 at 4:18 pm #817329Two examples of drawers with half-concealed dovetails, where the sides are basswood and birch, respectively. Functionally there have been no issues with mixing either softer hardwood, though basically everything went to pot with the latter project. Thankfully all the defects are only visible at close-up.
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You must be logged in to view attached files.24 September 2023 at 9:54 pm #814308Could it be a tapered saw blade, as the upper one in the attached photo? I think that one of the tenon saws that Mr. P Sellers uses is an antique one with a tapered blade, so probably not a modern concept.
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You must be logged in to view attached files.31 August 2023 at 4:46 pm #811848Hi Tom,
Just a few thoughts based on that I’ve not always been succesful using a combination square.
If the bottoms of the pin recesses are square to the faces of the drawer sides and the bottoms of the tail recesses are of constant depth (para-planar to the drawer front), then – as both gap lines are of equal width – there should be a close fit.
With all due apologies, could it be that the width of the rebate on the inside of the tail piece is one mm less than the depth of the cut line?
Another of my culprits behind this situation has been failure at completely clean out the corners between the ends and bottoms of the pin recesses. Checking with my ordinary sliding square didn’t quite reveal the problem, but a wheel gauge set to the depth would grab as it caught non flat parts of the recesses.
Finally, and this is really silly: if the sides aren’t square to the front, then there will be a gap.
13 August 2023 at 6:31 pm #810301Hello Joost,
The strength of a tenon and mortice joint to a significant degree depends on a snug fit of the shoulders – assuming there are shoulders, of course, But if so, then perhaps drawboring is an alternative that will help with both tight fitness and the lack of support for the upper end of the tenon. 3/8″ dowel bars appear to be quite readily available, and they also do away with the need for clamps.
30 July 2023 at 8:12 pm #808797Hi Antonio,
Looks to me as the tangential aspect of a flat sawn board with the grain not running completely parallel to the surface. There is a little pin knot, but I don’t see the pattern of a major branch taken off. Am good at being wrong, though.
The slight change in colour at the upper right of the second photo (left on the first), looks like an ordinary growth ring in transition between tangential and radial, and having absorbed some form of extractive. The rot in beech that I’ve seen has been dark grey or black and with fissures running along the wood.
In summary: looks like very decent beech, that I would be happy to use. The kitchen top at our croft looks quite similar.
22 July 2023 at 6:48 am #808204Sorry, but I forgot to mention that the top needs to be ripped along the edge. Then, when the batten is in place, the ripped off piece is glued back again, hiding the opening of the socket.
There is a video on making a table with a drawer running through the front apron demonstrating the technique.
21 July 2023 at 12:43 pm #808119Dear Jeff,
Looks nice.
Hope you don’t mind a thought on cupping too much. If it is caused by seasonal changes in humidity or by tension in the wood, then a batten running as a non-tapered sliding dovetail along a socket at the bottom of the top can be an alternative.
An 8 mm (5/16″) deep x 18 mm wide dovetail, bevelled at 1:4, resulting in 2 mm wide shoulders worked on the piece seen in the picture.
[attachment file=”808120″]
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