Unexpected (But Not Surprising) Benefit of Tumbling Blades in Sand

I just might tumble all blades from now on, even those that I will mirror-polish manually afterward. Because after two-three days of tumbling, an interesting phenomenon appears. Something that is not surprising when you think about it, but I did not in fact expect it upfront.

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It is difficult to snap a picture of it, but here it is visible – the blade is all shiny except that triangular shadow at the tang. That is an area where the blade is not hardened.

In this specific case, this is OK. The tang should be soft and a soft piece of the spine, especially near the tang, also does not hurt. And because this blade will be blackened with oak extract, the visible difference in color should not be a problem.

However, there were two other blades, one from spring steel like this and one from N690, that had shown this discoloration in areas where soft steel definitively is not desirable – one about 2 cm at the tip and one ca 2 cm of the blade near the ricasso. Those were improperly hardened and I did not find out during the scratch test right after the quench, because most of the blade was OK.

That is quite useful and thus I really consider incorporating sand-tumbling not only as a cheap surface finish but also as cheap and easy quality control.

Not Tacticool, But Hopefully Cool

A friend tasked me with making a knife for their spouse. The spouse does not cook, so a kitchen knife was not an option. But they do occasionally go on a camping trip or a forest walk with the kids, so we eventually established that some sort of camping/bushcraft knife would be best.

The ideal material for a knife of this kind would be spring steel, but since it is unlikely that their life will depend on it, N690 should suffice and rust won’t be a problem. So I set to work and I have made this.

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

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

The blade is 160 mm long and 5 mm thick at the handle and tapers toward the tip. N690 steel, sand tumbled satin finish. The handle is made from rotten willow wood stabilized with green-dyed resin. It is a big boi – it weighs 300 g (and that is with the fullered blade and handle is lightened too by holes in the tang). A sharpening angle of 25° should guarantee that with occasional use, the blade will not need sharpening any time soon. Despite being thick, it is reasonably sharp and cuts well, because it has a flat grind all the way to the spine. It is balanced at the bolster, and it packs quite a punch, as a knife of this type should. And because the spine is so thick, it should withstand even some serious abuse should the owner decide to inflict it on the blade. Which I suspect they won’t.

The accessories are a ferrocerium rod and carbon steel striker as a fire starter (more for fun than real purpose, matches are better) and a sheath with a pouch for these. Theoretically the carbon steel striker is not necessary, but when testing it out, I got the subjective impression that carbon steel strikes better sparks from the ferrocerium rod. I might be wrong, I could not think up an objective test for that.

Making fullers by hand is very difficult, it will probably take several more blades before I get it right. I am currently wracking my head about how to make an accessory for my grinder that would make this difficult task just a tad easier. So far no success, just a few semi-functional, semi-failed attempts.

How Many Nuns Would Nunchucks Chuck…

… if nunchucks could chuck nuns?

I am going to ramble a bit about my pet peeve nonsensical weapon bans and regulations around the world. I am in no way a freedom absolutist in this regard. Weapons are dangerous objects that definitively need to be regulated, and the more dangerous a weapon is, the stricter regulations regarding its accessibility to people should apply. There should be background checks, aptitude tests, mandatory training, and licensing for all firearms. But banning hand weapons is useless and oftentimes downright silly and makes no sense whatsoever.

Take for example the titular nunchucks. I have trained with nunchucks as a kid, I have never hurt my self and I never broke anything either. It was great fun and it was beneficial to me. They are great for hand-eye coordination, great for training speed, and spatial awareness, and it was a good workout too. What it was not – despite me not knowing it at the time – was useful combat and martial arts training applicable for self-defense. Nunchucks are a terrible weapon, although they are better than nothing (not better than running away).

To my great surprise a few years ago, I have learned that nunchucks are banned in Germany. Not only to carry around but to own or manufacture. You will not find Karate or Kobudo class in Germany that trains in their use, not officially at least. That is daft, especially with the reason given – they can be used as a garotting weapon. Well, theoretically, maybe, but they would be awfully ineffective for that. That is not what they are designed for.

And since I have already sold knives to people in Germany, I have looked into laws regarding them a bit and those are too silly squared. Knives that can be opened with just one hand are banned to carry. Knife with a fixed blade can be carried if one is currently performing an activity facilitating its use – like fishing, hunting, or mushroom gathering – but I have read some stories about knives confiscated on the way to a forest, so it can depend on how pissy the policeman you have encountered feels that day. And balisongs are banned to even own, just like nunchucks. I did not dig too deep into that, but whatever the reason, it is just silly.

Because balisongs are really, really bad pocket knives. Their advantage over other pocket knives is that they are very easy to make, but that’s it. They cannot be made very sturdy, their very construction means the blade will be always a bit wobbly. They cannot have any meaningful handguard so when stabbing something with them, there is always the risk of your hand slipping on the blade upon hitting some resistance. And several other things make them bad. The only thing they are really useful for are the same things that other small pocket knives are useful for – cutting food, opening packages, and so forth.

When watching some random videos on YouTube recently I have learned that flails and maces are allegedly illegal in parts of Canada too. And again, I fail to recognize the reasons for this.

In the UK, the reasons given for these imbecilic weapon bans are to prevent gang violence. It does not seem to work. You can ban nunchucks and kusaris, but you cannot ban keychains. You can ban knives, but not screwdrivers. You can ban maces, but not spanners, and hammers – and guess what, the gangs are using these everyday objects exactly for that reason.

I suspect that these weapons were made illegal because they were portrayed as very deadly in 90s action flicks. If so, then legislators enacting these laws should learn the difference between a movie and reality. Bruce Lee movies are NOT documentaries!

But OK, when these laws are in the EU, they are very silly, but at least they are somewhat consistent with the overall culture. But when they are enacted in the USA, their silliness condenses into a black hole of daftitude.

Now one can say that nobody actually needs weapons like nunchucks, maces, or similar and I should shut up about this. I disagree, but I won’t argue against that right now.

 

Bobbin Lace: Peacocks

My mother had a “peacocks” period now and has made several. This was our classical collaboration where she bounced a few ideas of me, I then suggested some improvements, she has drawn it again and so forth until she arrived at a design we both liked. Two of them she has even changed after she has already done them in lace because they did not come out right.

All except the last one are approx A4 size, that last one is about half of the others.

© 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.

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

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

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

Sharpenatrix

Walter Sorrells has recently made a video about a sharpening tool for his belt grinder, which gave me an inspiration for finally making my own. I have been planning to do this for a long time, but watching that video helped me to solve the final piece of the puzzle.

Walter Sorrells is of course not only a much more experienced knifemaker than I am, but he is also much better equipped. So my project has all the hallmarks of my handmade tools – it is crude and made from scraps.

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I have started with a very rough sketch of the jaws and I have also spent some time calculating trying to establish various proportions whilst finding a compromise between stability (shorter arm is better) and consistent angle across the blade (longer arm is better).

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Here you can see it in full when finished. Jaws for holding the blade are mounted on a ca 40 cm long 10 mm stick with a ball on the lower end. The ball goes into a socket at the end of an arm that can slide forward and back with regard to the belt, thus adjusting the angle at which the edge leans on it.

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The 10 mm steel rod is recycled from our old heating oven. The plastic ball at the end is an old furniture handle. All the wood is recycled from an old bed.

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The jaws are made from 4mm mild steel and lined with 0.25 mm bronze held in place by means of double-sided adhesive tape. Near the tip of the jaws are two 5 mm pins that are screwed into the smaller jaw and slide into holes in the bigger jaw. They provide an end-stop to rest the blade against in order to fix it easier into the jaws and they also prevent them from wobbling.  The upper screw tightens the jaws and the lower one sets the distance between them, so I can vary it according to the blade that is being sharpened.

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Originally, I have planned to make the socket from wood and I expected it to take a lot of time. But I got a brilliant idea during the work to use a lid from a fabric softener bottle. It cracked during work, but I still could attach it to the arm with a  screw and a large washer. After that, I have covered the screw head with a piece of PVC flooring and after some consideration, I have also added two hard gaskets to keep the ball centered and to provide ever so slight resistance to movement.

The sliding arm can be fixed in position with a fastening screw salvaged from some defunct kitchen appliance from a long time ago and a galaxy far, far away, from times when things were made to last.

When the weather allows it, I will give the thing a coating of grey paint so it looks slightly less amateurish and also to protect the wood from moisture. And I will mark a scale on the sliding arm so I do not need to bother with measuring the angle.

I do not expect this to save a lot of time. I already sharpen knives on the belt grinder and it does not take me more than about five-ten minutes per blade. But it will make the job a bit easier and the angle should definitively be more consistent, which is a plus. I am not one who is overly concerned with sharpening angle, I think that anything between 15° and 25° works just fine for most knives, but consistency does have an influence on the durability of the edge. For example, the N690 steel that I am using for most of my knives allegedly should not be sharpened at a too steep angle (below 15°) because then it tends to chip and break. With this tool, I can at least be definitively sure that I won’t go any lower than that.

We shall see how it works. I do have a lot of knives that need sharpening.

Kitchen Knives Set – Part 8: I Just Could Not Stand It

It is several months since the last update on this project, and there are reasons for that. Some have to do with the project itself, some do not. One of the reasons that are directly related to the project was that I had difficulty finishing the knife stands because in the cold weather the boat lacquer that I have decided to use for finish took an absolutely inordinate amount of time to harden properly. So prepare now for a really long post about how I made the wooden stands for these knives.

The original plan was to make all woodworks from jatoba and black locust, thus making the stands from massive hardwood. But since I have made the handles from the rather rare and precious applewood, I had a very limited supply. Especially when it came to the spalted wood. So I stood in front of a decision – should I try to make the stands match the handles or not. And I have decided to give it a try and make matching stands. Which means getting a lot out of a little.

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First I started by cutting the cores of the future stands out of some scrap spruce wood, of which I have an overabundance. Where I needed a thicker piece, I have simply layered and trimmed the thinner ones until I got the size that I wanted, with a generous amount of wood on both sides of each blade, especially for the stands where two blades were meant to be next to each other.

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This was the first time I have used expanding PU glue. PVA glue would have difficulty to set in my workshop, even with heating. This glue did harden within a few hours enough so I could safely take it indoors for the rest of the curing process.

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

After these cores were glued and cut to the final size, I have sanded all flat surfaces. Not very thoroughly, just enough that I do not get my hands full of splinters.

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And since I had to do with what little of the precious wood I had, I have decided to use thin boards/veneers for finishing. I have cut approx 5 mm thick slices of the wood on my bandsaw and with a bit of luck, I did get enough of each of the three types of wood that I have used for the handles to cover the stands. Mostly. I could have cut even thinner veneers, like 2 mm, but 5 mm did save me a bit of work later on.

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Most veneers were cut with the grain, but I have also cut several pieces across the grain. Those I have glued on the end of the softwood cores and only after that I have cut the slits for blades. For each blade a cut just as deep as the blade is wide, so each knife has a slot fitted exactly to it. I took two passes on the circular saw for each slit since I have cut them about 1-2 mm wider than the blades are, so the knives come in and out really easily without scraping the sides. That way at least I hope the probability of something getting stuck to the mirror-polished blade and scratching it later on in the stand should be reduced. I could not of course make the slits too wide, because then the point could get stuck in them.

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Wherever veneers had to be put side-by-side, I had to carefully fit them together so the seams are as small as possible. In one case I also had to change the design of the stand since I did not have any veneers long enough and I did not want to link veneer strips lengthwise. Two strips beside each other do connect almost seamlessly and even when they are visible, they do not disturb. But a clear line across the grain or the pattern in the spalted wood would surely look at least odd.

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

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

To fit the veneers properly all around I had to first glue up two opposing sides, trim the excess, grind it to flat, and only then I could glue the other two sides. Trim and sand again and I got finished building blocks for the final products.

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There were some minor problems – the spalted wood was soft and got chipped – so I had to fill in some places with resin mixed with sawdust and/or offcuts.

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Then there was a lot of sanding. It made me glad to have a hand-held belt sander. I will probably have to buy an orbital sander too if I am going to make more of these.

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Since the resulting pieces had very sharp edges which would not look very well in combination with the rather rounded handles, I have decided to round them significantly. I did not use a router, although I do own one. Instead, I have just sanded all future edges down with 60 grit sandpaper over a soft sponge until they looked right, and then I have polished them.

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In one of the stands, the pieces were connected by big enough flat surfaces that I could reliably clamp it all together during curing, but int two of the pieces had to be connected by relatively small areas and at an odd angle, so I have used a piece of wood to drill holes for dowels to prevent the parts from shifting during the glue-up.

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And here they are, fixed to small boards for stability and handling during the paint job. I have decided to use boat lacquer for the stands because infusing such big pieces with resin would be very, very expensive. I did not expect it to take as long as it did though.

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After the first coat with highly diluted lacquer the grain and fungus patterns popped up on all pieces quite significantly. I have left it dry for two days and then gave it two more coats with diluted lacquer in two-days intervals to stabilize the soft and spongy wood as much as is possible. And after that, it was five-six more coats with undiluted lacquer, with a few days wait and thorough sanding between each coating. When the last coating was drying, I got tangled up for several weeks with other works, mainly in the garden, and only this last week did I get round to do the last hand sanding. I sanded the pieces in increasing grits up to 1000 and there I did stop because I wanted them to have the same satin finish as the handles.

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I have modified my buffing compound for the stands, but it is still perhaps a bit too hard. It did buff the pieces nicely though, so I cannot complain. Too much. I did achieve my goal, which was to make the stands reasonably similar to the knife handles. There is a bit of difference in color because the handles are thoroughly infused with resin, but I do not think it is a problem and neither does anyone who has seen it so far (about 7 people).

And this week I finally got to the last step in this rather long project – making the stands to actually, well, stand. Out of the three, only one was big and heavy enough to be stable – the one from mostly healthy wood. For the other two, I did not have enough material to make them with a wide enough base, so I had to fit them with legs. I have considered several options and I have decided to go with a 6 mm stainless steel pipe. Aluminum would look cheap and brass would clash with the visible stainless steel tangs on the knives.

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To drill the holes safely and at a proper angle, I have first made a little board that could be fixed to the stand at the angle I wanted it to be in one direction. In the depicted case, the board is at the angle the leg is supposed to be when viewed from above. Into that board I have drilled a hole at an angle it was supposed to go into the stand. Then I could fix this board to the stand by the simple method of copious amounts of paper masking tape and drill the hole safely and at the correct angle.

By the way, I did not do any measuring or sketching for this. The “correct” angle was established by eyeballing.

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With that, I was still not done with this piece of wood. I have trimmed one end of it at the angle the leg will touch the ground and used that as a guide to filing down the end of the pipe flat-ish.

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Gluing the legs with epoxy was pretty straightforward after that and they were already mostly – although not perfectly – flat against the plate.

© Charly, all rights reserved. Click for full size

They did need a bit of sanding to get them perfectly flat, but not that much.

And that is the project almost finished. All that is left is to sharpen the knives and make pretty pictures. Hopefully sometime soon. You can see here that I have also already begun the next batch of knives. Yup, that is how long it took for the lacquer to harden, I have managed to grind and harden ten new blades in the meantime.

The next – and last – post in this series will be pure cutlery porn. This is one of those rare instances where I think I have done a good job.

 

DIY Reusable (Hopefully) Etching Stencils

At about the same time that I have decided to leave my job and try to make a living as a knifemaker, I have also decided to number the blades that I make. And since my logo is my initials in Glagolitic script, it seemed only logical to use Glagolitic numbering too. Almost nobody will be able to read the numerals without aid (including me), but I do think that arabic numerals would look a bit odd in combination with my logo, so I have decided to go through with the use of Glagolitsa.

The numerals consist mostly of straight lines and dots, so it is kinda easy to cut them in adhesive tape with a scalpel tip. But it costs relatively a lot of time – I have spent about ten minutes per blade since I have moved into two-number digits and things will only get more and more complicated after that. So for a long time, I was thinking about how to make stencils.

I could not use the same method that I use for my logo, because the numerals are so tiny that even if I were able to cut them into the 1 mm silicone sheet, the etching solution would have trouble reaching the surface through such a narrow, water-repelling, canal anyway. I needed something thinner. Like a sheet of paper. But how to waterproof a sheet of paper? I have tried it with wax in the past, and that did not work. Beeswax contaminated the surfaces and paraffin wax is not elastic enough. It would be ideal to infuse the paper with silicone, somehow, but how? I was thinking about trying to buy pouring silicone for forms, but I was reluctant to spend money on it not knowing upfront if it will be of any use.

And then I got a much simpler idea, so simple that it does make me wonder how come I did not come up with it sooner – linseed oil. I have printed my numerals on a sheet of paper, soaked it thoroughly in linseed oil, and left it harden for a few days. The resulting sheet was repelling water and bendy enough to adhere reliably to the blades, whilst stiff enough for me to be able to cut the numerals.

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Each stencil has two parts – one for vertical lines, one for the rest, since oftentimes it is not possible to cut the whole number at once for obvious reasons. The oiled paper is also transparent enough to be able to place the second part over the first reliably-ish enough.

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Since the stencils are so small that some unwanted etching around the edge of the stencil is a real risk, I have made a round shield from silicone to protect the surrounding area and also to provide a better seal for the stencil itself. And when I was at it, I have made two new graphite etching electrodes with the felt permanently attached to the graphite. One with big rectangular felt (left) for the logos (not used yet) and one with a soft, round tip specifically for the numerals.

And I am pleased to say that it all works. I was numbering blades 40-48 just a few days ago and it took me a lot less time than before – and this time I still had to cut the numerals into the paper. Next time I should be even faster because the stencils are already cut and I see no reason why they should not last until the next batch of blades is ready for etching. Here you can see one test-etch of the number 40 on the tang and the number 41 on the blade.

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The numbers are not perfect, but they are not worse-looking than they were before. Indeed it could be argued that if the numerals were perfect, it would undercut the handmade look of my knives which always have some minor irregularities in them no matter what I do. Or it could be argued that I am setting my goals too low, well…

We shall see what the public decides once the pandemic is over and I can go and sort out all the necessary paperwork to be able to actually sell them.

 

I Almost Didn’t Fail the Second Time

My first attempt at big blade ended up in a disaster and after several years of procrastinating the issue ended up as a smaller (though not small) knife. I gave it a second shot because 1) I really need a machete 2) I want to learn to make these big blades for I have big plans for the future, that will no doubt never come to fruition.

And as the title says it, I almost didn’t fail this time. At least, I do have a serviceable tool to use in my garden.

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Spring steel, blackened with oak bark. 4-6 mm thick, 51 cm overall length. Fully hardened, spine tempered to spring.

This time things went reasonably well, but I was suspecting that I have ground the fullers too deep. At least they were passably symmetrical – there was no trouble in the quench. The blade came out hardened and mostly straight, and the very slight bent it has developed (circa 1-2 mm over the whole length) was easily corrected with my unbender after heat treatment.

However, when I was trying to polish the blade and smooth out the fullers, it turned out I was right – I made the fullers too deep and near the tip I have thus ground through. But it might not be a functional issue, just an aesthetic one, so I have decided to finish it, albeit with less attention to detail than I would had it been a complete success. I have filed the hole bigger and oval with diamond-coated files (to remove any stress-risers) and I have stopped polishing the blade, especially the insides of the fullers. I just gave it a few buffs with scotch brite discs for angle-grinder and then it went into the oak bark tee for a nice night-long bath.

Handle fittings are from bronze and handle scales are from pickled black locust. I did want the blade to complement the previous one since they will both be used by me in my garden. This handle is specifically fitted to my hands, so nobody with different-shaped hands would probably feel comfortable using it. I have no idea yet how it will work out in the long term, but it did feel perfectly fine when I gave a few whacks to an old wooden board with it.

I might make a scabbard or a sheath for it too. I am currently thinking about whether to make a double-sheath for the pair or a separate sheath for each item. Both options have pros and cons. Not that I do actually need a sheath for wearing them, they are unlikely to ever leave the house further than the 60 or so meters that is my backyard long, but they are both sharp and big and dangerous and could get rusty, so I need an option for safe storage, both protecting them from elements and me from injuries when they are not used.

Bobbin Lace, Pandemics and Christian Morals

You may be justifiably baffled about the title – what do these three things have in common? And, understandably, you probably can’t guess the correct answer. Because that answer is my maternal grandmother.

I have never met any of my grandparents, all except my grandfather died before my parents even met, and my grandfather has died when I was merely three years old. So I know very little about any of them, except for what my parents have told me. And today I would like to share a story about how the bobbin-lace-making tradition started in our family. It is not a nice story.

My grandmother has broken her leg during play when she was four, she fell from a haywagon and her leg got between the spokes of the wheel. Her parents wanted to take her to the hospital, but her father’s mother has refused to pay for it, saying that God will take care of things. He did not. In fact, it got worse to a point that when they finally did go to the hospital, it was too late and the leg was beyond repair. It stopped growing and no attempts at mending it worked, including a graft of healthy bone from the other leg.

A few years later, when my grandmother was seven years old, the Spanis-flu pandemics has broken out and her mother got sick. She was delirious from fever and kept hugging my grandmother saying “My poor child, if I die, I want you to die with me, they will torture you when I am gone.”  Unfortunately, she died and…

From what I gather, my grandmother’s father was a mild-mannered man. A gamekeeper who preferred the quiet of the forests to people. He was not very keen on religious practice, saying that he meets with God in the forests and does not need to go to church. But at home, he was completely in tow of his abusive, miserly, and religiously devout catholic mother, who ruled the family with an iron hand. They lived at a homestead, and that means a lot of work needs to be done on daily basis. Oftentimes hard work even for healthy people.  And everyone was expected to do their share. My grandmother had three healthy sisters, and she was constantly shunned and mocked for not being able to work properly. At one point her grandmother has refused to “feed the cripple any longer” and when she was eleven years old, she was sent to a cloister.

A cloister that was adjacent to a castle and has provided a lot of free-child-labor to the said castle. My grandmother was of course not suitable for many works, but she was very apt with her hands, and she learned several useful crafts there. Including bobbin-lace making – the cloister made bobbin-lace for the countess. She liked those crafts, but my guess is she would probably like them better if they did not come with a sidedish of beatings and hunger as a punishment for not meeting the daily quota of work.

At seventeen years old she was poised to become a nun, but this is when her luck finally broke for better. An employee of a mask and wig lending shop from a big city was shortly at the cloister and she noticed the exceptional skill of my grandmother. And she asked her if she would like to come to the big city to work at the company. And she did. But she was not of age yet, so she needed consent from her father to go.

The parish priest had a bad conscience with regard to her, for not putting pressure on her grandmother to send her to hospital in time. And one nun has liked her and wanted for her a better future than the cloister. So they conspired to prepare the paperwork and catch her father at the marketplace, where he went alone without being supervised by the abusive family matriarch. And he signed the papers without arguing.

And that way my grandmother escaped abuse and finally got to live on her own. Two years later her bad leg had to be amputated, but she got on to live a happy (for the times – WW2, then totalitarian communist rule etc.) life. And she kept making bobbin lace and passed the craft onto one of her daughters. Who passed it onto me, where it stops.

Today, my mother has finished another of her masterpieces. A round tablecloth, 80 cm across. She worked on it for 220 hours and has used 1530 m of thread. It is beautiful and I do wish I had a cheerier story to tell with it.

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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.

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

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!