Kitchen Knives Set – Part 7: Getting to Grips

These knives have full-width tangs, but no visible pins. As far as I can tell, nobody else is using this type of construction, so it might be somewhat unique

A few years ago Walter Sorrels made a video in which he tested various glues for fixing scales to tangs without pins. He made several mock-up knives from mild steel for this and they all have failed his stress test. Which consisted of tossing them in the air and letting them fall on the concrete pavement. As it turns out, the shearing forces during these impacts were too big for the glue to reliably stick to the steel and they all delaminated. But he gave me an idea on how to overcome this problem. I have tested the idea on one broken blade and it held out to several hammer blows before the scales delaminated  – and at that point, it was not only the glue that was failing but also the wood was starting to shatter and break. And since knife handles are not supposed to be hit with a hammer so I think it should be OK. I really hope it works out in the long term because I am going to make a lot of these. So if you want to know how this goes, read on. [Read more…]

Kitchen Knives Set – Part 5: “Fun” with Resin

Somebody somewhere in the comment section (I think on Marcus’s blog) expressed dislike for resin stabilized wood along the lines that it is the same as making the handles out of plastic. I disagree. Stabilized wood is a pain to work because it behaves like plastic in that regard, but it does not look like plastic and neither does it feel like plastic in the hand – it feels like wood. And as I was working on this project, I found out that it even sounds like wood – stabilized pieces give out very nice clonk-clonk when hit against each other. I think it might be possible to make musical instruments out of it, but I won’t try.

However, before said wood reaches its desired stabilized state, I have to work with epoxy resin. Lots of it.

I hate it.

It is gluey, it sticks to absolutely everything and it is transparent, so when it drops somewhere it is difficult to see in time. Tools and surfaces need to be cleaned with paper towels soaked in denatured alcohol, which is not cheap and the fumes do not smell exactly delicious. And the work needs to be done fast, because if the epoxy gels, it won’t soak into the wood no more.

With my macgyered vacuum pump I have reached a vacuum of 0,2-0,3 bar, which was sufficient for extremely porous wood, but might not be sufficient for this. Applewood has very small pores and is very hard, even the very decomposed pieces were still harder than for example poplar or basswood. So I have decided to bite the bullet and buy a small, cheap vacuum pump in the hope that it will work better. And it does – and it does not.

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Even with my poorly sealed pickle jar, I have easily reached vacuum 0,6 bar within a minute. The wood released so many bubbles that the resin developed foam head like beer.

However, the pump also got very hot after a few minutes of running, which made me a bit worried. My macgyvered pump was a bit cumbersome and awkward, but overheating was completely a non-issue. I am not so sure about this one. I hope it does not burn out before I at least get to sell some knives.

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Overheating aside, the wood soaked up the resin very nicely and although I have only used clear resin, it developed very nice and pleasant colors. The resin would cure over time at room temperature, but it is possible to speed up the curing by heating it to 60-80°C. So I did that the next day and I baked the pieces for two hours, after which I could appreciate the nice clonk-clonk that I was talking about at the beginning.

I have also approached the issue a bit more scientifically this time and I have weighed all the pieces before and after. Here you can see the results.

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This made me very happy with the results. The relatively healthy wood has gained approx 30% in weight, the not-very-much rotten root wood doubled its weight and the more decomposed wood has almost tripled its weight. All pieces of similar size weighed approximately the same after the stabilizing process, irrespective of what wood they were made of. And finally, all pieces when put in water either sunk completely or just barely floated with 99% submerged. So even the relatively healthy wood should be soaked up with resin to sufficient depth.

Now that the wood is stabilized, the only thing that is left is to psych myself up to go into the freezing workshop and finish the knives. Which includes first a bit of grinding and drilling, and then a lot of gluing. Even more fun with epoxy awaits, hooray!

Kitchen Knives Set – Part 4: Getting Some Serious Wood

Since I have spent more time making the blades than I originally intended, I have decided to go the full hog and NOT make the handles out of some plain wood. Instead, I have decided to kill two birds with one stone – to get some fancy wood for this project and to reduce the clutter in my raw material storage. I have decided to use the apple stumps that my neighbor gave me.

First I had to cut the stumps into smaller logs of course.

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That was not fun. Like, at all. I hate working with a chainsaw because the work quickly exhausts my meager strengths. Luckily the battery in this small saw gets drained after about half an hour of serious work, so with two batteries, I can get in about one hour of work before having to take a long break. Which is about the duration that I can do this without trouble.

Even so, before I was done it did actually happen once that the batteries held longer than I did and I got unpleasant mild hypoglycemia. That did not happen to me for a long time, but it was a reminder that absolutely must not skip or delay meal breaks.

I also blunted and had to sharpen the chain at least three times because there were small stones embedded in the wood.

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Next came cutting the logs to a smaller size on a circular saw. Another not-favorite work of mine, since my circular saw is small and not exactly up to the task. I am also afraid of it most of all my tools. But I managed it mostly, although I too blunted the blade again by hitting an invisible stone inside the wood. That was not a happy week at work. I can tell you that. This I cannot sharpen myself, I have to pay for it and it ain’t cheap.

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Aaand more cutting! This time on my Crappola bandsaw. I “only” broke three saw blades before cutting most of the wood down to workable size and shape. And whilst these are cheap on an individual basis, three at once cheap ain’t no more.

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And these are the pieces that I have decided to use for the actual project – there is plenty more for future projects, including some smaller pieces of burl. So I did get some value for the destroyed sawblades, only not as much as I would like to.

On the left is some partially rotten but still reasonably hard and strong root wood. It still gives a nice resonating “clonk” when struck. I do love the stripey coloring, given to it by the decay.

In the middle is some mostly healthy wood, still completely hard and strong, but with a few cracks and occasional woodborer-holes. I hereby declare that those add to the character. They are inevitable parts of wood harvested from a tree that stood dead for several years.

And on the right is some really fancy looking spalted wood. This is so decomposed (by a fungus), that it is significantly softer and less-dense than healthy wood. It sounds a bit dull when struck too. But it is still not so soft and spongey that it would be unworkable on its own. That is important, otherwise I could not do my next step.

© Charly, all rights reserved. Click for full size.

© Charly, all rights reserved. Click for full size.

I have cut the slabs and I cut and ground rough outlines of the handles, with a few mm to spare. This will save me some resin later on and it will also mean I won’t have to grind away as much resin-soaked wood as I would otherwise. Which is good, because working resin stabilized wood sucks. Majorly.

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And now the wood is drying up on the heating radiator in my living room. Not only does it need to be completely dry before I proceed, but it also has to wait until my ordered vacuum pump arrives. I do hope it does arrive next week. It is already delayed a bit. I also hope it works OK and that I have not thrown 100€ out of the window.

I do love that I have got three sets of different woods, all from the same species but each with its own unique character. I do not think I will dye the resin for these and I will just infuse them with a clear resin, leaving all cracks and holes distinct and visible. I think there is real potential for beauty here.

 

Gingerbread Houses

My mom almost did not bake any gingerbread this year, she is not doing very well I am afraid. And I am trying to make knives when I have time and stamina, so I probably won’t bake any. But my mom did make two houses in the end, so here they are (below the fold). She loves doing these things and I am glad I invested money when I had it into automated devices that take care of the most laborious and heavy work so she can do it even now.

She complained a lot that her hands are getting shaky and the decorating is not as neat as it used to be, but she does that for several years now. I still think she makes beautiful, original, and wholesome gingerbread decorations and I keep telling her.

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© Charly, all rights reserved. Click for full size.

[Read more…]

Kitchen Knives Set – Part 1: Thoughts and Design

So, this is my next big-ish project, I have decided to make a basic set of kitchen knives – three knives and honing steel. I am not entirely sure about how useful honing steel is with knives from N690, but I have used it on my mother’s knives and it seems to work. It does not appear to hurt. If this small set works out OK, I will make more in the future and perhaps add some specialized knives along the way, but this basic set is meant for casual cooks like myself (and indeed most of my friends), who do not need a special blade for every task and will be probably very content with one knife for 90% of work.

And because this time I am preparing perhaps for more future projects, I have made templates in photoshop, printed them out, and laminated them in transparent foil for future use.

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© Charly, all rights reserved. Click for full size.

The grid is metric, with the smallest scale being 1 mm.

The “meat” knife is a de-facto universal knife, one that I expect to take care of that 90% of work. Medium-sized blade with a round tip, ergonomic handle for firm grip, suitable for slicing protein as well as fine-dicing herbs and vegetables. And for remaining tasks, there is a small peeling knife with a sharp tip for piercing and a relatively straight blade for scratching-peeling, and a big chef knife for tackling difficult cabbage and for those occasions when cutting a lot of big-ish vegetables or huge chunks of whatever is necessary.

The chef knife has holes along the blade edge, which should help with reducing the sticking of whatever is being cut to the blade. It is easier to make than hollow grind or S-grind and it does work too. The handle is ergonomic as well but it is formed with a focus on two main uses of such a big blade. The thicker butt with a hook end prevents the knife from flying out of the hand when chopping, and the thin front with a lot of space for fingers allows for a choked-up grip with the index finger and thumb on the blade for fine slicing and dicing with a rocking motion.

All these designs should work as expected since they are based on knives that I have already made in the past. Of these, the least tested is the chef knife, but I still do not expect any trouble. I won’t follow the designs exactly, they are just approximations and I expect to tune them up a bit during the work. Any thoughts and remarks on the designs are welcome, as well as any suggestions for further additions to the set ( I am thinking about fish-knife and cheese-knife).

However, I will definitively introduce one new and relatively original feature right now. One that I have not seen used by another knifemaker (which does not mean nobody does it, I just did not see it done). As you can see, there are four-five holes for pins in each tang, which might seem a bit excessive and dorky-looking. That is because I need more pins – two will be wooden and two will be metallic. And they will not be visible. That is, the knives are designed as full-width tang, but the pins won’t appear on the outside of the handles. I have tested this idea on one broken blade and it seems to work perfectly OK for a kitchen knife that won’t get hit with a mallet or hammer too much. Or at all, as things should be.

So stay tuned for the following articles with a full write-up of my manufacturing process for this project. I am decently far already given that I only could work three days this week. And because a video was requested, I am filming (almost) all work as well. But I make no promises there – a future video is, at this time, uncertain and might or might not happen.

Whinge, Knives, Whinge

It took me four months to finish the batch of knives that I started in July. I have documented every hour that I have worked on knives, and the results are not good. I have only managed to work about 20 hours a week. Plus some hours that I have not counted, like when I was making new tools, repairing or improving them, etc.

Please allow me to whine a bit about the causes of that.

I either have chronic fatigue or I am a chronic hypochondriac. I am reluctant to go to a physician right now, partly because of the ongoing pandemic and partly because of last year when after several months of pain, I never got a conclusive diagnosis – and the pain only subsided after a course of steroids that I got for a really bad but unrelated virus (possibly flu) that snuck up on me right before Covid hit Europe. So I am not all too optimistic about our GP being able to help me with this.

I have been more or less tired ever since that possible flu. You remember that short walk in the forest in August when I brought home two full shopping bags of ‘shrooms? It took me three days to get over that, and one of those days my legs hurt so much I was barely able to go to the loo. After just several hours of hand-sanding knife handles my back and hands hurt for two days. Etc. etc. ad nauseam. Add to that the necessity to spend time carting my parents to/from doctors, stacking firewood to the cellar, caring for my trees, and the result is that I do a lot less work than I want to.

I have never seen the point of exercise because my body never reacted to it the way other people’s bodies seem to. I did get stronger, but only in relation to my starting point. In high school, when I could exercise under professional supervision free of charge, after months of work I was barely getting just below the level where my schoolmates have started. This year is that – only worse. I am not going exactly downhill, but just barely. Plus my hands started to hurt again two weeks ago. With the sun gone, I have at least looked at what safe dose of Vitamin D I can take in supplements and I am taking that because it seems to help a bit.

Whining over. I hope it gets better. At least it is not getting worse.

The last knives I have finished are four universal kitchen knives from a batch of five blades. One of those blades was not suitably hardened after all- near the tang was about 2 cm soft part. I do not need to toss it, but I do need to try and quench it again with the next project.

These are a bit heavier and thicker (3mm) than my previous knives of this type because they are made from what was left over from the slabs for chef knives. I have also changed the geometry of the handle a bit – instead of a rounded rectangular profile it has a rounded trapezoid profile. They are also about 2-4 mm thinner overall and 5 mm thinner and shorter at the front to better allow a choked-up grip with thumb and index finger on the blade. And they are pointy this time.

One knife has the handle from apricot wood and I have tried tubular pins filled with the same wood. I think it looks good and I will use that idea in the future again.

© Charly, all rights reserved. Click for full size.

© Charly, all rights reserved. Click for full size.

Two knives have the handles from pickled black locust. It is perfidious wood, in the future, I have to be more careful – the scales were probably not fully dried when I ground them to final size and they shrunk on me a tiny bit when I was finishing the surface with resin. So the tang does exceed the handles a tiny bit. That can happen due to a bad shaping job too, but that was not this case – they were perfectly flush originally, I swear. Lesson learned I have to put this wood in the oven for an hour or so before glue-up and grinding the outline. Now I can forget the lesson before finishing the next batch.

© Charly, all rights reserved. Click for full size.

© Charly, all rights reserved. Click for full size.

© Charly, all rights reserved. Click for full size.

© Charly, all rights reserved. Click for full size.

And last was fitted with padauk wood that I have again got for free with steel shipment. A prime example that there really is no need to use tropical woods, it does not look that much better than the black locust.

© Charly, all rights reserved. Click for full size.

© Charly, all rights reserved. Click for full size.

Knives are a bugger to shoot, I will have to build myself some better lighting system. Either the blade is over-exposed, or the handle is under-exposed, or the colors are off, or all three.

If you are interested in knife making, on Sunday I will start a detailed series about my next knife-making project. Not because I am qualified, but because I want to.

Brass Chisel

I made a new tool. I do not know whether someone else is already using it in a knife-making context, I would not be surprised if it were so. But I never heard anyone talk about it – a small chisel made from brass. I think it is a very good addition to my toolbox, well worth the ten minutes or so that I have spent making it. The inspiration were tools that I was using in my previous job to clean burnt plastic off of various testing devices.

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This may sound like a joke tool, akin to the inflatable dartboard, chocolate kettle, or ceramic rivets, but it is not. But why would anyone make a chisel out of a soft material like brass, that will not hold an edge?

I am glad you asked.

When making knives with the use of epoxy glues and resin, an inevitable problem arises – epoxy stuck to places it should not be stuck to. I am always doing my best to clean any rogue epoxy from the bolster/blade boundary etc before it hardens with a towel soaked in denatured alcohol, but the epoxy tends to flow and bleed over during curing too, plus there is often some contamination on the blade where I fail to spot it in time. That needs to be scraped off, very carefully, without damaging the blade surface.

With my last batch of knives, I have used with great success a square piece of brass, so for the last few pieces, I ground it roughly into a chisel shape and fixed it to a handle. And it works great, exactly as it is supposed to work.

There are several reasons for using brass and not other materials like alluminium or mild steel:

  1. Brass is harder than epoxy, resin or wood, but softer than even unhardened steel. So it can be used to scrape the glue off steel not only on the blade but also on the tang, without damaging the polished surfaces.
  2. Unlike alluminium, Brass does not come with a hard-oxide layer from the shop, neither does it form one over time. It forms a patina, but that patina is not hard enough to scratch steel. Alluminium does scratch steel, partly due to the oxide layer, partly due to galling. Ditto mild steel.
  3. Brass is one of several so-called non-galling alloys, but alluminium is a strongly galling metal. That means that brass does not lead to wear and tear when it slides on a steel surface, whereas alluminium will tend to contaminate, even if not necessarily scratch (if you remove the oxide layer beforehand thoroughly), steel on contact.

And thats all, folks. If you need to scrape glue off of polished surfaces, a brass chisel might be just the tool for you.

 

My Little (Stitching) Pony

Since sewing leather sheaths whilst holding them between one’s knees is a huge pain in all kinds of regions, I have decided to bite the bullet and build myself a small stitching pony. It is very simple, but, as usual, it took me way more time to make than it should have. Here it is for you to admire.

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It is made from reclaimed firewood, so I have spent a lot of time sanding of splinters.  The “H” formed base is for stability, but the two planks are only fixed with one screw each and tightened only with a winged nut. That way I can loosen them, and fold them so the pony can be put out of the way and leaned against a wall when not in use, together with other useless junk I posess, like painter’s easel.

You can also see that I have bought a suitcase for my leatherworking tools. It is already full to the brim and I have barely begun :(.

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Jaws are covered with leather, here it is not fully trimmed yet. You can admire the high precisisn’t with which I am usually assembling these tools.

The right jaw is fixed, the left jaw swivels on a hinge. They are tightened via one long screw with a winged nut. The screw is deliberately very loose, so it cannot be overtightened.

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A piece of wedge-shaped hardwood with slits slides on two screws and under the winged nut, allowing for a sort of easy quick-tighten and -release tool.

It works as it should. Like all tools, it gets some getting used to, but it does make the leather stitching several orders of magnitude easier. I have tested it today and I was definitively a lot quicker. And my back hurt less.

Expect some leatherwork in future too. Hopefully.

Card Weaving

kestrel is graciously sharing her woven artwork with us, and she’s taken the time to teach us about how this type of weaving is done. I’m sure you’ll agree that it’s fascinating.

 

Card weaving (or tablet weaving as it’s also called) is a very ancient craft going back quite a ways. A very wonderful find was the Oseberg ship with two women buried in it. Among the many textiles found, there was also a loom with the warp still attached to the weaving cards. However historians believe card weaving is much older than this 9th century find. Card weaving was a technique people used to create very strong and sturdy as well as ornamental bands. Some of the very ornamental bands seen in religious textiles were created this way. 

 

Although I used to weave quite a lot, for whatever reason, I had never tried card weaving. I’d had to give up weaving (there was no room for my very large loom and I had to sell it) but recently I decided I wanted to weave again. My big loom was gone, but you don’t need much to do card weaving. 

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[Read more…]

Punch and Die (and Fun)

I do not have the genius of Leonard da Quirm, but I do share one trait with him – I get easily distracted and sometimes spend several days trying to shave off a few minutes of some task or save a few bucks. Sometimes the effort definitively pays off – as in the case of my belt grinder or my forge burner, sometimes it is a success but with a question mark whether it was worth it – like the unbender (now I know it was worth it, btw, I have used it several times already and it is time-saver), and sometimes it is a bit of a flop, as when building a vacuum pump. If I had a definitive fail, I do not remember it, and so I allowed myself to get distracted again these last two days.

I have a problem with making metal bolsters, handguards, end-caps, and pommels. As in, it is difficult to get material thick enough to make them pretty, and even if it were not difficult, the result would be overtly heavy and thus would put the knife balance totally out of whack. The proper way to make bolsters and end caps is to make them hollow, and there are techniques for that. One of them is forging – as I did in the rondel dagger project. But that is labor-intensive, has poor reproducibility, and requires special tools anyway. Or I could buy prefabricates and adjust my design(s) to fit what is already on the market. Screw that!

So I have decided to make some new tools, and test them. The inspiration was a technique of minting coins before the invention of fly screw-press, which I have seen as a child in some black and white movie which has shown the making of Prague groschen at Kutná Hora. I remember nothing else about the movie except the part where they strike a punch on a silver blank with a hammer and thus make a coin. I think there was some drama and history in there too…

First I have made a die out of 5 mm high-carbon tooling steel. It consists simply of two holes – one for the bolster and one for the end-cap  (I have chosen my small hunting knife as a pilot project because I think the design will be improved a lot by it and because I do plan to make more of these knives in the future). Second I have ground two punches out of square stock of high carbon tooling steel that I have scrounged at my previous job. Grinding the forms with angle grinder was not easy, but it was not insurmountably difficult either. I had actually a lot more trouble with welding onto it the 15 mm round stock for holding the punch in place and for striking – my welding sucks, bigly. And because at least the first strike needs to be real mighty, I have built a small wooden stand to hold the punch in place for that.

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With the assembly on the concrete floor, as you see it in the photo, I have given it a mighty whack with my puny Mjolnir. And I rejoiced because it was a success. To protect the floor from damage I have put it on a steel plate for subsequent tries and I went and punched four sets for the four blades that I have currently in making, three out of brass and one out of pakfong.

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The pakfong was a bit thicker than the brass so it gave me some grief, thus the surface is not so smooth on the end-cap – I had to whack it several times and it wandered off the die and I struck it without noticing it. But that should not be a problem, there is enough material in there to polish these dents out.

It took me mere minutes to punch all these, and after a long time, I was really, really happy for a bit. There are a few details to iron out – like making a better stand for the punch, making it so I can put it safely on my anvil, figuring out the ideal amount of overhang and so forth – but it functions as it is and it is a massive saving in time already. Whether the knives will really look better remains to be seen, but I am confident they will. Further, this opens a lot of new possibilities for knife designs for me.

I Probably Won’t Do This Again…

After a month of work, I am finally at a phase where I have something to show for it. The kitchen knives are in the tumbler for the second day now, tomorrow I shall check if they are ready or not. But it need not hurry, I have enough to work with – eight fully polished blades.

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Today I have etched the logos and numbers on these because it is easier to do on a naked blade than on a finished knife. Now I can finally work on finishing at least some of these into final products while the kitchen knives tumble.

Working in bulk does save significant time and even resources, but 18 blades in one go was a bit too much. I am going to reduce the batches to 8-12 in size. That way it should keep its savings, but the polishing hell will not be that long. Polishing is extremely onerous and unrewarding work because one keeps doing the same thing day after day, working through the row of belts with very slow progress. With one knife, it is one-two days of a boring slog. With eighteen knives, it was three weeks – and one of them got broke and nine only to 120 grit before going into the tumbler, if not for that, it would be even longer.

These are not perfect, some of them have serious problems regarding symmetry, although only in one case it is visible with the naked eye. On all of them is it visible with calipers. I am starting to doubt that I will ever do a good job, but there are some signs of progress. One of those signs has, unfortunately, a bit of a negative consequence on these blades, all 17 of them – they are a bit thicker than I expected (a few tenths of a mm). That is because I have gotten a bit better at working on the belt grinder and thus I did not grind away as much material as I used to by having to correct mistakes

Mind you, they all will cut perfectly fine even so, and some of them already do despite not being sharpened yet. But a thinner blade will always cut better. On the other hand, these should be extremely sturdy and should be able to withstand even some serious abuse, and that is a plus for a hunting knife. We will see if there will be people willing to pay for these without bashing me over the head afterward.

Now to think about how to dress-up these blades and the accompanying sheaths. I think I have quite a few more weeks of work ahead of me, but now it should be creative work, and therefore much more fun.

Well, It Sucks, But…

My goal in mcgyvering a vacuum pump was to remain under 100,-€ – which I did – and get better results than I have achieved with my shop-vac setup – which I did too. Still, I do not know whether to be disappointed or satisfied.

I wanted to utilize things that I already have, which includes several water pumps that are used to water bonsai trees and vegetable beds in summer and pumping water out of the cellar in the winter and some spare piping from house renovations. So I had to buy only the things for making the vacuum pump itself – in combination with a water pump, the best option seemed to be something based on the venturi principle.

So I went and bought these parts:

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The parts were connected to each other more or less in the order as they are laid out on the picture. The black plastic hose connector was fitted into the brass one to lower its inner diameter. The brass hose connector right next to the right side of the chrome T junction is the inlet nozzle – I have glued an old tip from a silicone sealant tube (not depicted) in it to get the position and size of the nozzle correct. Into the upper brass hose connector was glued the white plastic 6 mm hose connector for the air suction.

So water comes in the T-junction from the right, gets squeezed through a nozzle which sprays into a slightly bigger opening in the outlet left, behind which is again a big pipe. The spray drags with it the air surrounding the nozzle and that way achieves suction through the top of the T-junction.

I am not able to write-up complete how-to, but this is the final product up and running in a vat of water.

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The bubbles show it is working. When I connected the suction tube directly to a new vacuum manometer, I got a suction of whopping 0,6 bar, which did really impress me. Unfortunately, I do not get anywhere near that when I connect everything to the jar. After a few minutes, it stabilizes at this.

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0.22-0.25 bar is still a bit more than what the shop-vac could achieve (which was 0.2). So it is usable and it is a definitive improvement because unlike the shop-vac it can run non-stop with zero risks of overheating anything, and it also makes nearly no noise, so a win there too. But when it achieves this, it still bubbles, so it still draws air. And when I close both ball-valves on the lid (one ball-valve is for pressure release, one for the suction), I start losing pressure in the jar really quickly. That tells me that the jar is not properly sealed and this here is not the maximum this setup can achieve, but an equilibrium between the pump and the improper sealing.

I had to make a new lid from five layers of plywood for this, with two ball-valves and the manometer, so there was a lot of potential for failure. But I did use water/airtight plastic sealant for everything and I went over all connections once more, yet I still cannot identify the leak(s). If it was a pressurized container, I might find the leaks with help of soapy water looking for bubbles, but I do not know how to check vacuum tightness.

So this is where I am now and this is where I leave this be for a few days at least. It has occupied me for three days already, time to go back to making knives.