Project Badgermascus – Interlude 4 – New Tools

I have decided to make a sheath for the knife, but since the blade and the fittings are quite fancy, a plain leather sheath would be unbefitting. So the time has come for me to learn some fancy leatherwork. As you know, I am quite fond of making my own tools, but this time around I have decided to bite the bullet and buy some basic stuff for starters.

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These are really just the basics – a swivel knife and six basic stamps, a beveler, and a groover. The cheapest ones there were to find.

I will surely make some of my own tools in the future, but these should, hopefully, suffice for a start. They do not allow me to make anything that cannot be done with the tools that I already have – but they allow me to make those works much easier, more consistently, precisely and quicker.

Now I am going to cut up an old leather handbag and test some design ideas.

Project Badgermascus – Part 9 – Almost Done

The knife is done about 95% now. I have peened and ground flush all the pins on scales without some major failure, although there did appear one tiny crack near one of the pins ‘sigh’. I have sealed the crack with super glue and sanded it over, there is nothing else that can be done about it.

I did not do a very good job at the pins, I must say. I think the mistake that I make is leaving myself way too much material to move, which leads to a lot of problems later on. I must remember that for 3 mm pin it is quite enough to peen less than 1 mm material into a recess just 0,5 mm deep. It is not as if the pins need to hold extra-strongly.

But, it is done and it is what it is. I applied a little bit of patina to the pins. Not to make them black, just to make them ever so slightly aged. Funnily enough, the patina has highlighted some of the imperfections – and that made the whole assembly to look actually better. Only you must forgive me for now for not revealing the whole knife yet. There is still a lot of work to do before I consider it publication-worthy, do not expect that very soon.

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I am thinking now how to best seal the surfaces and the patina. Either beeswax, or drying oil. Or both. Any suggestions? I have zero experience with patina on metal jewelry, which essentialy is what this is.

Project Badgermascus – Part 8 – To Peen or Not to Peen…

Today was very stressful, although I did not, in fact, do too much work. But I was agitated about it so I procrastinated a lot, putting off each step for fear of mangling the work and losing a lot of progress. That will also be the case tomorrow.

Today was the day of gluing the scales to the tang. And because I wanted to peen the pins from the beginning, I also had to prepare for that.

For I lack proper ball-peen hammer for this kind of job. I have a wide variety of cross-peen hammers, but only one, big, ball-peen hammer. And that is way too big and chunky for 3 mm brass pins. They are not sold in any stone shop around here, and ordering one online would again put me in the age-old problem – is it worth buying something if the shipping costs more than the product?

So I have to make do with my smallest cross-peen hammer and a few thingamajigs that I have made myself to make the job easier and, hopefully, better.

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Peening pins in bone is kinda dangerous. Bone is hard, but not particularly strong and it can easily split. To try and reduce the risk of splitting I have therefore pre-peened one side of each pin before assembly, so the pins are shorter and thus less likely to bend when I am peening the other side. To make a better job of this I have taken a piece of mild steel from a failed attempt at burner diffuser and I drilled in it 3 mm hole, chamfered to about 5 mm recess on one side. Then I held the pins in a vice and peened one end into this recess.

The second tool that I have made is from an old hook-nail. It is very old and therefore good medium carbon steel, hardenable, although not to the highest degree, and very tough. If the tool works, I am going to carburize the surface and quench it.

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First I have cut off the hook and the tip. Then I have center-punched the center of the square where the tip used to be and dished it out first with a 3 mm bit and then 7 mm bit in a hand-held cordless drill. Then I put a big diameter ball burr for die-grinder into the drill and rounded the inside of the dish and I ground the edges round with a file. I have tried it and it seems to work well when used after the hammer for the final touches on the edges. So I hope to get nice round peened pins tomorrow.

With that done, I have also repaired one of the scales – two holes were a few tenths of a millimeter off so I could not put the pins comfortably through all holes. Not a big problem, I have filled the two holes with quick-curing epoxy mixed with bone dust and drilled them new. You would not notice there was a mistake there if I did not tell you about it.

Then I was ready for the job that I was putting off – the glue-up.

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I have used slow curing epoxy, with work-time 1,5 hours, instead of the 10-minute one that I have used previously for kitchen knives. The reason for this was not only to reduce stress and the possibility of a complete fuck-up, but also the fact that this simply could not be done quickly. Mixing the epoxy, slathering it over the tang and attaching the pins and the scales was simple enough, but after that came the difficult part – to clean all the squeezed-out epoxy from the fileworks. I have used first small pieces of kitchen towels soaked up in denatured alcohol to wipe out the biggest excesses and then a toothbrush soaked in the same to tease-out glue from al the nooks and crannies. I do hope I have made a good job because there is no way back now except either take it as it is or to drill out the pins, smash and grind out the bone and start with the handle scales all over again, which would not be fun at all.

Project Badgermascus – Part 7 – The Pinkening

For the next attempt at the patina, I had to think of a more fool-proof way to mask the areas of the assembly that are not allowed to come in contact with the chemical solution. I have used plastic packaging tape in the past, so I tried it this time. But the one I bought this time is extremely difficult to take off because the glue is too strong. That makes it also difficult to apply tightly around the blade since once it gets stuck, it cannot be corrected. And, the masking around the filework was a major headache-inducer, there the tape was totally insufficient.

So I needed something that is resistant to water and water-soluble chemicals both acidic and basic, hot and cold, something that will show me clearly what is masked and what is not, something that can be applied with high precision and good adhesion to complex surfaces and simultaneously can be removed easily later on without damaging the patina.

And after some thinking, I did come with a solution that worked really well. I made everything pink!

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That is the cheapest nail varnish that I have seen at the local drugstore (2,-€ per bottle). Afterward, I have added the packing tape on big surfaces, but I think it was unnecessary and just me being overcautious.

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I proceeded to make the patina on brass fittings by alternating between acid bath (HCl, very diluted) and polysulfate bath (with occasional brushing with a soft brush under running water) until I have received a color that I was content with, which is sort of metallic blue/brown/dark gray, very similar shade to the oak-tannin patina on steel.

Cleaning off the varnish was a bit of a hassle and used up a lot of paper towels and acetone, but the important bit is that it could be done, could be done well (it was easy to spot uncleaned places) and did not scratch the patina on either the fittings or the blade. I will probably buy heaps of cheap nail varnish, it opens up great possibilities.

Project Badgermascus – Part 6 – Trials and Tribulations

I have spent both Monday and Tuesday finishing flattening, drilling, and fitting the handle scales and the brass fittings.

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First I have sieved some bone dust that I have collected through a fine nylon mesh (from pantyhose – I do not wear them, but they can be quite useful in the workshop, so I have indeed several in a drawer). I mixed then the bone dust with five-minute epoxy, filled the hollow back of the bones with it and heated it with a heat gun to about 70°C (not so hot you cannot touch it, but hot enough you cannot press your hand against it for a longer time, a hairdryer would suffice too for this particular task) for quicker curing and stronger bond.

After it completely hardened I ground the back flat again and proceeded to drill the holes for pins.

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Drilling the holes was relatively uneventful. Double-sided tape was very useful in holding the scale on the tang and the whole assembly on a flat piece of wood for drilling to avoid chipping of the bone on exit. Also, I have used blunted and overheated drill bits to hold the scales in place for a good fit and I did not mess up the job terribly. I did make minor mistakes on the left handle scale, but those should be correctable when fixing everything together.

With the scales drilled and fitted against the bolster, I proceeded to make the brass pommel fittings. That went really well, and everything went smoothly. Too smoothly you might say. I glued the brass fittings in place, peened the pins and ground, and polished them over.

That is where the problems started, and I must say – they are not all my fault.

The first problem was that the round stock I have used for pins apparently has different chemical composition than the flat profile used for fittings. Had I known this, I would not file them flush and I would leave them slightly proud of the surface (“admitted” instead of “hidden”). However, there was no way back once I ground them flush, so I was hoping they will get hidden under the patina.

But the patining did not go well too, in three ways.

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The first  – I have made a mistake – I have not masked the steel properly. I thought I did, but I just did not. And as one Czech rather rude but astute saying goes – ” myslet znamená hovno vědět” – “to think (assume/mean/guess) means to know shit-all”. So when I was giving the brass a nice hot bath to copper plate it, some of that bath leaked under the masking and copper-plated and etched the blade in some places too.

The second – the different brasses did not take copper plating identically, it was a lot more difficult to copper plate the pins than the rest. It took over an hour to do on the pins what took mere minutes on the rest (which exacerbated the problem with poor masking later on).

The third – when blackening, I have made the solution probably way too concentrated. It has covered the parts in a nice jet-black matt color almost instantly. But that color has completely rubbed off when I washed it with water and brush. I did not realize the true cause of this so I tried it two more times, but it just did not take, especially not on the pins, After the third attempt I thought I am done on the pommel at least, but it flaked off the next day again.

These mistakes are not catastrophic, but they are a major setback. I had to re-polish everything (done), re-etch with ferric chloride (done), give the steel new tannic-acid patina (in progress), and only after that is done to my satisfaction, can I again try to patina the brass.

However, I have to deal somehow with the pins now. They are ground flush already, but since they will not take the patina the same way the rest does, I must leave them visible. And that means probably leaving them polished and not applying patina to them at all. I will do that and then I will decide whether I like it or not. If not, then I will have to drill them out and either replace them or, if I bungle that job (which is very likely) to make completely new fittings. Either way, it is at least one day, and possibly several days, of work before I can progress further.

However, there did come one good thing out of this – I found two new recipes for black that do not require copper-plating the brass first. One requires hot-bath with ammonia (CuSO4+Na2CO3 – precipitates basic copper carbonate which after filtering and washing with water can be dissolved in hot water by adding ammonia), so it is a major stink and not exactly easy or quick. The second one works at room temperature but is rather caustic and dangerous to handle (HCl + potassium polysulfide). I will probably try the second one now, although I do not like very much working with caustic solutions, since my equipment, as you have seen, is not exactly suited for that kind of job.

Project Badgermascus – Part 5 – Handle Scales

Tomorrow you will get a break from this project, I promise. But today, the Great Flattening from yesterday has continued.

After some deliberations I have decided to try and go for fully blackened brass fittings. That means that the blade will be dark grey, and the fittings really, really dark gray. What kind of handle material should I use? Marcus has sent me a nice piece of stabilized spalted maple, but I do not think it is the right material for this project. Ditto, any of the dark woods that I have. I think the blade deserves the poshest material I have available – bone. I think it will provide a nice contrast to the dark metal.

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Which meant I first had to rough-cut the scales with a hacksaw, which is one hell of a job, let me tell you. Bandsaw or any electrical saw is a big no-no for cutting bone, this has to be done manually. Including pre-cutting he flat sides, before grinding them truly flat.

Thus I had to spend the whole working day with a respirator and my fingers are all sore now. Because the grinding had to be done manually too. Belt sander does work on bone, but it destroys belts way too quickly for my liking and as I learned in the past, these thin flat pieces would have a tendency to be dragged out of my grasp, increasing the risk of injury or bungled work. So flatstone+glue+sandpaper it was. Maybe after I build myself a disk-grinding attachment this work will be easier, but now it is not.

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The scales are ever so slightly bigger than the tang and thicker than the bolster now, and they will remain so. I do not intend for a flush fit, but for a proud one ( I have seen English-speaking knife-makers refer to it as “heirloom fit” although I was not able to find anything specific about it, so I am not sure that is the correct term).

The principle is the same in carpentry – whenever two surfaces join, you can make the joint either hidden or visible, but it should not be visible because you failed to hide it. So if you make it visible, it should be apparent that it was intentional. Like gluing in spacers, making the surfaces meet in a groove and not on a flat, etc.

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Today’s work ended in the kitchen, where the two rough-ground scales ended in a pot at 60°C for an hour or so with circa a teaspoon of washing soda and one spoon of washing powder in 1 l of water to dissolve and wash out as much of remaining fat as possible. In the end I have added a teaspoon of hydrogen peroxide to whiten the bones a bit, although complete whitening is not possible on these.

Tomorrow when they are dry I shall fill the hollows on the inside (where marrow used to be) with epoxy to make them flat. After that, I can start the remaining works, i.e. fit and polish the pommel, drill all the holes, and finally, the glue-up. We will see how that goes.

Project Badgermascus – Part 4 – The Great Flattening

Today I have started the work on the handle, starting with brass fittings. First I have cut four pieces of brass, two for the bolster, two for the pommel, and I drilled 2,5 mm holes in the bolster pieces. On the left piece, I have then cut M3 thread and on the right piece, I have widened the holes to 3 mm.

For pins, I am going to be using a 3 mm brass rod. I cut 4 small pieces and on each, I have made a bit of M3 thread to go into the left side of the bolster (and later on the pommel). The M3 threads are, strictly speaking, unnecessary, but I find they help with two things. First, they help to keep track of which part is left and which is right, so I do not confuse them at some point and make a false cut with a file. Second, fiting the two halves together is easier, because the pins hold fast in place and do not fall off when manhandling the assembly.

I guess these preparations should not take me too long. They took me over five hours. The drilling, cutting etc was not the biggest issue. The biggest issue was the tang. During polishing of the blade it became noticeably thinner, and because the polished area bleeds over to the tang, the tang was not flat anymore – it was a few tenths of a mm thinner at the bolster. So I went and flattened it on a stone.

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As you can see, the tang has relatively deep gashes cut into it with the edge of the grinding wheel. Those are there for three purposes – they reduce the weight, they provide a good grip for the epoxy later on, and they reduce the area that needs to be manually ground off when making the tang flat.

Even so it took me a lot longer than it should have because I did not have the correct sandpaper readily available. What you see here is green corundum, which should be used only dry and only for wood. I have to buy very coarse wet & dry sandpaper, but I keep forgetting and the coarsest I have in stock is 120 grit, which is not nearly enough for this.

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And this is where I am now. Next, I will polish and finish the front side of the bolster but not assemble it. Then I will make the handle scales, fit and drill those, and only after that is done I will drill and fit the pommel part. I have not decided yet whether or not the pommel needs a hole for a lanyard.

The way things are going, I have still quite a few days of work ahead of me.

Behold: The Unbender!

As I wrote at the beginning of my making kitchen knives project (oh my, is it over a year already?), the steel bars often need straightening before a knife can be made out of them. The method I used then was not particularly time-consuming, but it was very annoying, with the screws constantly falling off to the ground and me cursing all the time. So I have decided to build a jig to help with the job. And here it is.

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This simple thingie took me a ridiculous amount of time to make. Like, three or four times more than it probably should. It might even have cost me more time to build it than I will ever save by using it, depending on how many knives I will make in the future.

The principle is simple, there are three rollers made from old piping and some ball bearings. Two are fixed to the base plate and one is on a plate sliding on two columns opposite them and center between them. A screw in the center can push the upper roller down between the two stationary ones and thus it can bend steel.

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The use is easy. Put the end of a flat bar between the rollers with the concave side down, tighten the central screw a bit and pull the steel back and forth end-to-end through the rollers (but careful not to pull it out completely, because that would mean starting over). Then check for straightness, eventually tighten the screw a fraction, pull, check again, rinse and repeat until the bar is straight.

It works actually very well. I have straightened all my bar stock in minutes and to a better degree than I was able to achieve previously. But still…

Well, hopefully, the finishing works on the forge will go a bit faster, because without the forge I can’t do squat.

Women Artisans on Youtube – Carpenter

3x3Custom – Tamar is a Youtube channel that I have found interesting enough to actually subscribe to. She is one of those people who likes to experiment and invent things, which is exactly what I like too. I have learned a lot from her and I cannot wait to put some of those things to use, even though my equipment is not as fancy and I will inevitably be forced to improvise a lot.

The video for today is one where she makes very cool patterned boxes for sick kids – out of scrap wood.

 

Making Kitchen Knives – Part 16 – Human-knife Interface

Last time I did this, I shaped the handle-scales first, then I fumed them wit ammonia and then I glued them onto the knives. This time I have changed the order of doing things, but time comparison should still be possible.

After taking the pieces of wood out of the solution I have left them dry. First for a few days outside, out of direct sunlight and out of the wind, with both end-grain ends covered with plastic to reduce cracking (still insufficient, next time I will have to try something more drastic). After they were dry and stink-free, I put them for a few days into the direct sunlight to dry even more, and then I left them to stabilize in the workshop for a few days. That way the wood should be neither too wet nor too dry and hopefully, it won’t change in size too much.

When I started to polish the pieces to sort them out properly – any markings were taken out by the solution – I could not find the oak pieces anywhere. So I took an offcut that was not in the solution and I polished that a bit and I realized that it is not, in fact, oak, but an especially dirty and grimy piece of black locust. I do not even remember where I got it and why I thought it is oak in the first place…

Anyhoo, after grinding all the pieces to flat and parallel, I drilled the holes for pins, cut all pieces to a rough shape on the bandsaw and I paired them up and I shaped and fully polished the forward-facing facets since those won’t be accessible once the scales are glued on. What I learned here was that I will need some finer scaled drill bits, since different woods react differently and when you drill with a 6 mm drill bit, the resulting hole can be anywhere between 5.5 and 6 mm. And trying to force the 6 mm brass pins through some pieces was a real pain in the nether regions. I have to drill the holes in wood ever so slightly bigger than the intended pin, but whilst 6.5 mm was fine for the softer woods it was almost too much for the harder ones.

The next step was glue-up.

To get as near perfect flat surfaces as I can, I have bought a spray-on glue and I used ti to attach a piece of coarse sandpaper to a granite tile. It worked really well, I have got a very nearly perfect match between the tangs and the scales on all twelve knives, the best result I have got yet for this type of handle construction. But I also managed to get a lot of glue on my hands and I lost the spray nozzle when wiping it off and it took two days before it resurfaced under the shop vacuum. So yeah, not my finest hour and the good came with some bad-ish.

During the glue-up, I have suffered from a common ailment –  the insufficient clamping power syndrome. I had to do it in two stages, gluing six blades in the evening and the remaining six in the morning next day, Which was not too much of a problem this time,  since I was tired and I would have to call it quits anyway, but I will probably need some more clamps or maybe even some thingamajigs for gluing the scales on the tangs more efficiently.

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And this is what I got in the end – a pile of roughly shaped handles attached to the finished blades.

During the subsequent grinding to shape with a 40 grit belt, I still could not do too much to evaluate the real effect of ammonia fuming on these woods, but I did get some inkling of what the results might be already. And let us say that for some of the woods I have preliminarily considered the results promising, for some surprising and for some completely “meh”. More about that when the knives are finished.

This whole step took me approximately 73 minutes per knife, and that is a significant improvement against last time – 38 minutes, 34%.

The last step is polishing the handles up to ~300 grit (already done) and putting on a protective coat of boat lacquer. That will take about a week, an hour or so a day. We shall see how that goes, but that part should be relatively free of any surprises.