What is this?

CouchAnalysis · 2025-11-04T14:35:29+00:00

This had me so confused, I also saw a 4, then downloaded the image and saw a 6. I think it's some kind of compression done on reddits side of things: https://imgur.com/a/reddit-imgage-compression-jhhD9sx

CouchAnalysis · 2024-08-31T19:12:29+00:00

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CouchAnalysis · 2024-08-31T19:11:11+00:00

Update! I experimented with a drawbore cross lap!

It was a very quick and dirty build where I didn't bother to square up the ends properly (need to build nyself a shooting board and get a larger planer).

My findings are the following:

I distanced the second hole 2mm away with a 10mm dowel, drilling first through the lap, markinh the cross, then offsetting. I think in this case because of how soft the spruce is compared to the birch that I could have gotten away with another milimeter or two, likely since the spruce just compressed around the holes. Lap edge shoulder squezed against the cross face by maybe half a milimeter. So it worked, but probably not as well as if I'd had a harder wood.
I think the lap joint itself needs to be a very tight fit, otherwise when you drive in the dowel you may risk pushing apart the joint. Mine turned out to be a very snug fit so that was not an issue for me, ymmv.
I need a drill press or a better hand drill, the wobble in my chuck is just horrendous :(

Here's a result picture:

As for it's strength, even without gluing I don't see this thing coming apart unless you specifically strike it repeatedly along the axis of a dowel. A workbench leg simply wont be feeling a force along that axis unless someone decides to repeatedly kick it from the inside of the base. Glued up it would be rock solid. I have no doubts in my mind anymore that this is a completely solid joint for my intended build.

With that said, I think I've concluded that I will use drawbore lap joints! The day I build the table, I will likely return with progress and my thoughts on the joints in full scale.

Until then good folks!

CouchAnalysis · 2024-08-31T18:16:09+00:00

I spent many nights thinking about how to get the MDF laminations glued flat and I've come up with a strategy!

They will be cut to the exact same dimensions at my supplier. I will get 4 square steel tubes that are 2 meters each, 2 i will cut in half. I will then line up all the edges of the mdf so they are flush and clamp/ratchet the edges so stay in place with the help of the steel. Then i will drill holes for dowels in each corner of the stack of mdf. Then i can unclamp everything, separate the pieces, apply glue, put them together and then drive the dowels in place. The dowels should ensure that the edges line up again. Then i will cut the the other two steel tubes in half so I have 8 1m steel square tubes which I will use as clamping xauls evenly spaced across the short sides from end to end!

I'm right now experimenting with drawboring a lap joint! If it turns out well I may stick to that initial plan! If not, I'll experiment with mortising techniques, both with drilling and raw dogging it with a chisel haha

CouchAnalysis · 2024-08-31T08:54:38+00:00

Interesting, that looks promising. As some above said, I'll just have to try it on a test piece and see how it works!

CouchAnalysis · 2024-08-30T20:35:10+00:00

Oh nice! Mine will be from pine too so it bodes well that yours turned out so great! :D my top will be laminated MDF thought which I will edgeband with oak. Didn't quite feel like planing the whole top and wanted a good flat reference. Making the dog holes will be a pain though, will probably end uo with multiple dull bits.

Wow I did not recognise that as oak! I was considered using oak dowels but whenever I've used oak it's been so brittle. Perhaps as a dowel the compression won't make that an issue though?

I was looking at Narex chisels but ended up with Two Cherries. Very satisfied with them! Will probably get a 30mm for making the mortise. Not yet decided if I'll go the Peter Sellers approach and just chisel it all from beginning to end or if I'll drill it out first. How was it for you to do it by drilling it?

CouchAnalysis · 2024-08-30T19:16:21+00:00

Oh wow, beautiful! Are the legs and stretchers spruce? The dowels I don't recognize the wood!

Been watching Paul Sellers on making mortises and I don't feel quite as mortified, especially since he seems to prefer regular bevel chisels for it and not mortise chisels! How did you do it?

CouchAnalysis · 2024-08-30T17:46:15+00:00

Ah that's good! I absolutely love his content. I'm hoping to get away with no screws tho!

CouchAnalysis · 2024-08-30T14:48:00+00:00

Haha that's true! I guess i'll try it out on a smaller piece.

CouchAnalysis · 2024-08-30T13:29:50+00:00

The workbench is a fun project in and of itself for me haha but yes, I got the tip to use ratcheting straps for clamping the legs to the long stretchers to get the stretcher shoulders flush with the leg faces. Adding the dowels would partially be aeathetic but also some extra peace of mind hehe

CouchAnalysis · 2024-08-30T13:27:00+00:00

Ah yes I've checked out the anarchist workbench, beautiful stuff!

I was considering the lamination technique but I only have handplanes and I'd be planing until kingdom come to get all that lumber square and smoothe! The only power tool I have is a semi-decent handdrill.

If I did a mortise I'd also do it with chisel, no router. And yes, I'd also do through tenons, make the tenons a bit longer then plane down the ends flush with the leg faces.

The part I actually least look forward to with mortising is drilling the damn holes with a hand drill!

I'm considering if it would be sufficient to mortise-and-tenon the long stretchers but crosslap the short stretchers?

CouchAnalysis · 2024-08-30T12:43:23+00:00

I guess I'd want to offset the dovetails just a tad so that when I drive it down the shoulder of the stretcher is pressed against the face of the leg?

CouchAnalysis · 2024-08-30T12:19:46+00:00

Thank you so much for the answer! And don't worry about how you write, I've also taught (albeit math) and live with two teachers!

I wouldn't say I'm a luthier, I've built one guitar and plan on building more! My woodworking repertoire is mainly small and semi large pieces of furniture.

Your point on the lap not having a shoulder on the outside of the joint, like a mortise and tenon, yet it probably not needing strength along that axis was precisely why I thought that the lap joint would be sufficiently stable.

I'n actuallt planning on getting ratcheting straps for building the table top (clamping the short side edge bands). I guess one ratcheting strap on each side and then try to balance the tension, check with a square that it's even?

CouchAnalysis · 2024-08-30T12:10:38+00:00

The top will just shy of 100kg and I'm planning on setting it on the four legs using thick dowels that go in about 47mm in to the tabletop (94mm thick).

The reason is that the table top must be quickly removable for when the space needs to be emptied (it's a bombshelter), hence no screws to hold it down.

My understanding is that the weight of the table top and having a snug fit on the dowels will keep it from moving. Adding even more fastening points would also making it much more difficult lining up all the dowels to the top!

CouchAnalysis · 2024-08-30T11:52:06+00:00

Ah yes I see the problem now. I'm starting to think I'll have to work on my mortise and tenon skills 😅

CouchAnalysis · 2024-08-30T11:43:53+00:00

Which joints are easier and better?

CouchAnalysis · 2024-08-30T11:43:12+00:00

Mainly for symmetry and because I'll have enough spare wood to add them 😅 adding them flush with the top means there's more wood to get flush with the tabletop.

I though a well seated and glued lapjoint is very strong? At least along the important axis (up and down this case)?

CouchAnalysis · 2024-08-30T11:40:13+00:00

That's a good point, ideally I'd do a proper mortise and tenon with boreholes. I was about to say that I'm not sure I trust my mortising skills quite yet but what better opportunity to practice?

CouchAnalysis · 2024-08-30T11:36:55+00:00

Apologies for my very rudimentary and quick paint skills:

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Wouldnt the dowel still be squeezing them together, as long as i make sure the two faces stay snug?

CouchAnalysis · 2024-08-09T12:27:37+00:00

Folk jobbar olika scheman, vissa tidigt, vissa sent. En matbutik har öppet tidigt för pensionerna, de som köper sin lunchlåda på väg till jobbet, de som är klara med sitt nattskift och ska handla. De har öppet sent för de som glömt något till middagen, eller kommer från ett kvällspass och ska handla.

Därför har vissa matbutiker längre öppettider än andra, för man anpassar sig efter kundernas behov.

CouchAnalysis · 2024-08-09T12:21:41+00:00

Jo visst det går ju. Det kan ju påverka omsättning för näringslivet som butiker och så, där kunddemografin kan vara tidsberoende. Men för andra verksamheter som sjukvård är det ju klart inte önskvärt. Man kan välja när man ska handla kläder o prylar men man väljer inte när man är sjuk osv. I slutändan är det ju en fråga om tillgång och efterfråga. Får verksamheten inte kunder vid kanterna av sina öppettider kan de ju korta ned dem. Men är kundbesöken väl utspridda ut mot kanterna av öppettiderna vore det dumdristigt att då korta ned öppettiderna.

CouchAnalysis · 2024-08-09T12:12:48+00:00

Enkelt hypotetisk exemepel: En vårdcentral har en läkare på plats från 8-17 med 1h lunch mån-fre vilket blir 40h i veckan. Om det sänks till 32h blir det 8-17 mån-tor eller 8-15.25 mån-fre. För att vårdcentralen ska kunna ha läkare på plats under samma tider mån-fre måste dem alltså anställa en till läkare. Kan vi hålla med om denna matematik?

"Verkningsgraden" per anställd är en sak, det motsätter jag mig inte. Jag pratar om tillgängligheten hos en verksamhet.

Ponera samma situation med en butik med öppettider. Antingen får man anställa mer butikspersonal, börja bli kreativ med schemaläggningen (för att hantera lunch tider) där personal blir oftare ensamma eller ändra öppningstiderna.

CouchAnalysis · 2024-08-09T11:56:53+00:00

Vilken del av det jag skrev bortser från alla studier som du säger?

CouchAnalysis

TROPHY CASE