The next installment of kestrel’s series is here and things have been getting bigger. It’s always fun when things get bigger.
Hey, take a look at this!
The next installment of kestrel’s magic making is here and there are tools to ogle.
It’s time to meet some of my favorite tools, the raising hammer and the planishing hammer. The faces on them are different shapes and that helps to shape the metal in different ways. The first one I’m going to use is the one on the left, the raising hammer.
It’s an open secret that LED fairy lights were invented for me. I love lights and there’s an abundance of solar powered lights around the house in summer and (rechargeable) battery lights in winter inside. So to combine resin and lights was a natural step. Especially since Marcus sent me a crystal mould and a handmade big globe mould.
I first tried my regular resin with the crystal. I absolutely love how the colour came out and how the copper metal foil really makes it all mysterious.
But, but, the resin clearly wasn’t the right one for such a project. It cured too quickly and with too much heat. You can see the bubbles all around.
So back to the computer to get a different resin. This one cures a lot more slowly and with less heat and is more suitable for bigger projects.
This one cured nicely without too many bubbles, though the longer time meant that my metal sunk down more than I like it. The opaque sheen is due to the acrylic paint I added for the colour.
I used one of the solar fairy lights Marcus sent in this project.
Now on to the big globe. I first ran a trial freezing water and then deemed it suitable.
The mould is not quite perfect with some bubbles at the top, but with such a project you won’t notice that anyway. This time, my metal rose to the top and there are still some bubbles, but I think they add to the otherworldly flair.
But man does that resin eat itself. I swear the mould was filled completely. It#s not a problem here, since a perfect globe wouldn’t rest nicely on my window sill, but I think it would be best to refill part of it after a day or so.
Kestrel has sent us the second part of her series and things are definitely happening.
In our last installment, I started to cut out a piece of metal so I could make something out of it. And at last, the first side is cut!
We’ve received a wonderful surprise from kestrel. She’s making magic and has decided to let us watch the show. This is part 1 of what may be about 5 parts and I am just as in the dark as you about what’s coming next. Kestrel will reveal all one post at a time so make sure to tune in for all the updates. That’s just the way magic should be, full of anticipation and surprises. And now… heeere’s kestrel!
A while back, Marcus posted about some mokume gane he had made, and the exciting adventures he had making it. https://freethoughtblogs.com/stderr/2018/03/27/mokume-gane/ I know it’s properly called mokume gane, but I like to think of it as MarcusMetal. (No doubt that will trademarked soon.) Much to my surprise, it arrived at my house early one morning. I immediately leaped up to polish part of it – away from the coffee, mind you – because I knew it was going to be very beautiful and I could not wait to see it. If you look carefully, you can see a pattern of swirls of copper against the nickel in the part that I polished. When I am done and I finish a piece, I will put a patina on the metal that will make the pattern show up in greater contrast.
Kestrel has finally shared some of her jewellery making with us and it’s phenomenal. What starts out as a pile of horsehair becomes ordered and ultimately beautiful at the hands of a master artisan. I’ll let kestrel explain the process…
I’m working on my website and one of the things that needs to be done is to re-shoot all the photos. Since most of my work is custom (in other words, people send me hair from their own horse, and then I make stuff out of it for them) I don’t have things in inventory, and that means I had to re-make all the items in order to take new photos. One of the things I like about my work is being able to transform my materials, whatever they may be but in this case a messy pile of hair, into something orderly and worth having.
Some of the braiding was done before it occurred to me to take a photo, but that messy pile of hair is going to be turned into 6 bracelets: 3 that are an 8-strand braid, and 3 that are a 25-strand braid, one each of white, chestnut and black. In case you are wondering: that messy pile of hair is made up of 1,761 individual hairs. That I had to count. On purpose. I don’t usually sit down and figure out things like that, because I just really don’t want to know; it’s a little depressing. But, if one is going to braid hair, one must first count it.
Part way finished, you can see the 3 8-strand bracelets are done and I’ve just started on the black 25-strand bracelet.
All done! It looks very different from how it started out. Now what I have to do is take good photos of each product so that hopefully, people will want one of these made from their own horse’s hair as a keepsake or memento. Just another day (OK, actually it was about two weeks) in the life of a braider.
Thanks for sharing, kestrel. I’m astonished at the precision and beauty of the finished product. I can’t begin to imagine the amount of work involved, especially the counting! These are surely cherished keepsakes. Why, it’s enough to make me wish for a horse of my own.
My new drill press arrived yesterday evening and I just installed it instead of the old cheapo one in my workshop. I must say that my first impression is absolutely great. I cannot definitively say whether it was a good investment or not – ask me again in a few years, because new devices tend to have some crucial mechanical parts (like gears etc.) out of plastic that wears out rather quickly and subsequently the whole machine has to be tossed – but on the surface the machine looks really great. Someone has actually thought about the design and, a rare occurrence in today’s world, the design is very functional and sensible. Use is very intuitive and all levers and settings are easily accessible. I worry a bit that the wheel might be too small to provide adequate leverage for drilling steel, but we will see. That is the only worry I have on first sight though.
The drill has a digital display that actually shows the rpm, which is very nifty – I will not have to guess by the sound. It has two main gearing settings and a continuous rpm regulator, so it covers very wide range of rpm on a nearly continuous scale without me having to flip v-belts. That is probably at the cost of some efficiency, but the max power (710 W) is higher than on other drill presses that I could choose from, so that might not be a problem for actual use, although it might be a problem regarding power consumption. But it is not a device that will run more than a few minutes at a time, so slight inefficiency is not as big of a deal as it woudl be for, say, bench belt sander.
As a knife maker I fell instantly in love with the quick-span/release chuck that is standard attachment. The chuck is simply ideal for holding down flat stock, something very obviously crucial for a knife maker.
And the laser cross! A LED light illuminating the worked area was just a final bonus on top of that. It was always a bugger to find and hit the tiny black dot on black piece of steel – now those troubles are, hopefully, over.
And of course it does not wobble in all directions so I hope I need not fear anymore drilling tiny holes and breaking two drill bits per each.
All in all right now I have no regrets for spending the non-trivial amount of money for it. I think it is money sensibly spent and I look forward to trying it out as soon as possible. I might indeed regret a bit not spending that money sooner.
As I said last time, I am going to make multiple knives in parallel, because I think that a non-trivial amount of time can be saved just by that. I had all my steel already straightened, so I could go right away to drawing, drilling and shaping. First thing to be done was to draw and drill one blade on one half of one steel bar. That I have subsequently used as a template to drill holes in the other half and in all the other steel bars.
For the drilling I clamped the template firmly with the drilled steel bars and before proceeding to the other side I inserted a steel pin in the drilled hole so the bars do not shift and slide. This has saved some time, despite it being a step with negligible time in the analysis, but my main hope here is that this work on multiple pieces in parallel brings better reproducibility regarding the hole positions and and that better reproducibility could save me some time later on when shaping the handle scales.
I have learned two lessons, one of them rather expensive. First lesson was that for this I have to take the 6 mm drill bits as de-facto consumable material, because I blunted and subsequently broke one towards the end despite using copious amounts of cutting oil. And I do not think it can be avoided.
Second lesson was that I really have to buy a new drill press, and preferably one with continuously regulated speed at that. My jury-rigged press with a very old hand drill has only two speeds and both of them are apparently too high for drilling 16 mm hole in 1,8 mm steel. Towards the end of the work the step drill bit overheated and it got irreversibly blunted on the 16 mm step. Ouch. That drill bit costs 40,-€. I think this investment is unavoidable, if I want to save time I cannot take the bit out and dunk it in water after each drilled hole, slower rotations would be better. And I cannot buy 40,-€ drill bit for each dozen of knives I make – that money be best saved for grinding belts. Hobby or not, at this rate I would spend the price of an acceptable small to middle sized drill press (300-400,-€) on the drill bits rather quickly.
Cutting the blanks in half and roughly cutting the outlines of the blades with an angle grinder did not take long at all. and working on multiple blades in parallel seemed to work comparatively well. But for the sake of precision, next time I will halve the blanks individually – two came out somehow too short and two too long. Not by much, but it is noticeable. The end result were three stacks of four roughly cut blades.
Before this step took me 15 minutes per blade, now it was 10 minutes per blade (teasing out broken 6mm drill bit and fruitlessly trying to drill a hole with blunted 16mm drill bit included). So I would call it a semi-success. I learned some do’s and dont’s and I achieved my two goals – the holes in the tangs align across all 12 blades nicely and I have saved some time without even really trying to.
I could not decide between multiple videos, as usual, and last-minute decision fell on this one. It is a nice piece of engineering and the video is reasonably short and packed with interesting information.
It might also be Halloween appropriate? I have no clue, since I originate from and live in a country with no Halloween tradition whatsoever and honestly I do not understand what Halloween is supposed to be about at all. But I read something about murderers and monsters the other day, so maybe an (alleged) assasin’s weapon might fit in.
I have a day off and I planned to do some knife-work, but I have to pass on that since I am still not well.
First thing first – today I tested the very nearly finished knife when I was cooking shrimp for lunch.
It handles well and cuts OK, but I really suspect it won’t hold an edge as well as it should. But the cheapo wood looks way more posh than I expected it, ammonia fuming really, really improved its looks.
And now to the boring stuff.
What I am doing here is actually a small-sized DMAIC project – an abbreviation for Define-Measure-Analyze-Improve-Control. It is a process used in industry to bring some logic and use of scientific method into improving manufacturing processes. Although as everything in today’s corporate culture it is used wrongly and heavily abused and misunderstood all over the place, because american-trained managers …. wheef, do not get me started on american-trained managers.
Aaaaanyway, in the first phase, Define, you should either define your problem or your goal or both. In my case, I have a specific goal – to get my manufacturing time of this type of knife under five hours of manual labor.
In the second phase you should acquire all measurements that you need in order to do something about it – in my case I have measured the manufacturing time of each distinct step in the process.
And now, in this post, I am performing the Analysis of said data. Total manufacturing time: 10:46, or 646 minutes.
A picture is worth a thousand words, so here is a picture.
There are of course multiple approaches one might use, but in this specific case I think that this suffices ample enough – it is so-called Pareto Graph. The balks are actual times in minutes for each step, ordered from the highest to the lowest. The black line is a sum of the relative proportions of these times to the total as one progresses from left to right. As you can see, I have ten distinct manufacturing steps and from those five steps constitute 90% of manufacturing time. These are the steps where I have to concentrate on actually reducing said time, because here my efforts have the biggest payoff. That does not mean that improvements in the other five steps are not worthy pursuing at all, but they are not worth pursuing at this time.
I have done one thing that is not normally done, that is I sorted from get-go the steps into two categories – low hanging fruit, where I think I can do improvements without too much hassle and without obtaining expensive or complicated equipment, and high-hanging fruit, where I can save time only through acquiring new skill or new equipment or where I think saving time is not actually possible in a meaningful way.
Now comes the next phase, which is to improve the process. I will try to implement some of the ideas for that I have expressed and make a batch of multiple (~10) knives with improved process. We will see how it turns out.
I will share with you a proper analysis of the acquired data, but I just finished a little experiment and I am too eager to share the results.
Without too big analyzing of anything, it is clear at even a casual glance that polishing is the most time-consuming part of the job. It is also the most boring part, in my opinion, because not much can be done and the opportunities for a mess-up are numerous. It is necessary to go through the laborious process for fancy knives, like Ciri’s dagger, but for a kitchen knife without any ribs or facets it is a waste of time.
For over twenty-five years, ever since I read about the technique in ABC as a kid, I wanted to try a process that goes under many names, “tumbling” being probably the most known one. I have even mentioned the device for it in the article “The Handmade Dilemma” as a “polishing drum”. It is a technique that has been in use for thousands of years, literally – for example Bohemian Crown Jewels contain precious stones that were polished this way. And it has been tried and used for knife finishing both on commercial and hobby scale. All that it takes is having the polished things in a rotating drum where they tumble over each other, sometimes with the help of a polishing medium, sometimes without. A very simple machine, and had I lived by a stream I would build a water powered one years ago. Unfortunately I do not live near a stream and wind is too unpredictable so I am stuck with using electricity, and I have not got my hands on a motor with the right properties yet.
But I got lucky, my colleague has bought small toy tumbler for his son when he was little and they do not need it anymore, so he lent it to me a few months ago. As you can see, it is not big enough to hold a knife, not even a small one, so after I let it run with a few pieces of unhardened steel with very mixed and generally unsatisfactory results, it has collected dust again.
But here was the second stroke of luck – I have bought a slab of high-carbon tool steel and I started to make myself a set of better hardness measuring gauges than the impromptu ones I have made from an old saw blade. I have already ground and hardened these little chisels to HRc 62, and I only cleaned the two big facets and sanded them up to 150 grit – that is the grit up to which the grinding and polishing is relatively quick and the blade does not heat up too much. I was not intending to high-polish these, since that would be silly. But I remembered the lent tumbler and checked if they fit in – and the did!
So I chucked the blades into the polishing drum with a spoon of jeweler’s rouge and half filled it wiht crushed walnut shells, mixed it all up and let it run for one day. Bugger – it got blocked after unknown time and I only found out next day. So I started it again for one day. And the change in surface was remarkable. It was not polished, but the perpendicular sandpaper scratches were no longer visible and the surface has got a very nice satin sheen to it. But I like my blades mirror-polished, so I started it for another day. I took another chisel out and subjectively there was no change against the first day, so I assumed that this is as good as it gets (but I will let it run for one more day). But I also assumed that since there are no visible perpendicular scratches anymore, I can quickly buff it to mirror polish with the three buffing wheels that I have – and I was correct.
Here you can see four pictures taken with my digital microscope (courtesy of our quality department who tossed it away because they lost the installation CD – so I took it home and downloaded free software). Each picture represents a section approximately 10 mm wide in reality.
After leaving the handle scales in the ammonia overnight, I took them out the next day, washed them in running water and quickly dried them. First by letting them for an hour above the stove in my workshop and when they were nearly dry, heating them carefully in 10 sec intervals in the microwave until there was no steam coming out. I do not count this time into the manufacturing time, because I have been doing it this way only to be able to proceed quickly and get the knife done this weekend. Normally I would let it dry by itself.
When dried, the scales had to be fitted to the handle – that is done by carefully sanding the faces that are glued on the tang on a flat stone as long as it takes to get them nicely flat. Then I screwed the handle scales without the blade together again and sanded and polished the two forward facing facets, because once the scales are on the tang, nothing can be done about them.
As far as the metal goes, I cleaned most of the scale from the tang with 80 grit sandpaper and then I cut two pins from 6 mm brass rod, hammered them through the holes in the tang and tried whether the whole assembly fits together without unseemly gaps. I was prepared to eventually sand a bit here and there, but it was not necessary, it fitted nicely. So I slathered generous amount of quick drying epoxy cement on all adjoining surfaces and squeezed the whole assembly gently in the vice. I cleaned the epoxy that got squeezed out, first by scraping of the excess with a piece of wood and second by washing the blade with paper towel soaked in alcohol. A piece of epoxy on the back and belly of the handle are not a problem, since those areas will be sanded anyway, but a real care must be taken in cleaning the blade and the forward facing facets of the scales thoroughly, because again, any mistake there cannot be easily corrected.
The epoxy that I was using was hardening quicker than I was happy with, but our local Baumarkt has “optimized” its wares selection a few years ago and they are only selling quick-setting epoxies now and I will probably have to order some slowly setting epoxies over the internet. I got lucky and I managed to get everything important clean before the glue set, but it was a race with time. That means I could not make any pictures of that process, so what you see is status just before applying the glue.
After the epoxy has hardened – in this case about 15 minutes later – I have made final shaping and polishing of the handle. I did not go above 150 grit sandpaper though, because that would be a waste of time with this wood.
Because the used wood was extremely porous, I had to stabilize it. Marcus has already mentioned the recent fad in knifemaking that consists of infusing the wood with resin. That would be ideal here.
Well, I lack the equipment to do that. But I wanted at least somewhat stabilise the wood even so. And I wanted to use the same finish that I have used on my mother’s knife, because it has proven itself to be very resistant. So I took the boat varnish and diluted it with acetone at a ratio approximately 1:4. You can see on the picture that the undiluted varnish is a lot thicker than acetone and it has sunk to the bottom of the jam-jar. However after mixing it did not separate again for a few days by now.
For the first dip I have put the handle in the heavily diluted varnish and I waited approximately 20 minutes until no visible bubbles were rising. Ideally It would be better to do this in a vaccuum-chamber, but acetone is very good wetting agent and this should be enough for at least a few mm penetration. After that I took the handle out and cleaned any varnish from the blade immediately with acetone. Then I have let it dry in a dust-free and well heated room. All that is left now is this week each evening after returning from work giving the handle a slight polishing with 150 or 180 grit sandpaper, dipping, cleaning, leaving it dry again until I am satisfied with the surface. I am not going to measure this time exactly because it is scattered a few minutes each evening over a few days. Lets say it is 30 minutes overall, including final signing of the blade.
That makes it 1:30 or 90 minutes for all of the work described here. That also makes the knife done for the purpose of measuring the time of my actual manufacturing process, so next time we can look at the data and look what (if) can be done there to make it more efficient.
I have decided to make the handle on this knife from an old piece of wood I have cut from a palette that stood outside for quite a while. I do not know what wood it is, I suspect birch. It is extremely weathered and looks kinda crap. But there is a trick to make such old wood look very fancy.
I have done most of the work per hand, first splitting the piece of wood along the visible crack, then cutting it with small hand-held saw to very roughly the final shape and drilling the holes for pins. So far this work was pretty uneventful and straightforward.
As you can see on the picture on the right, I have fixed the two halves with screws to make the final shaping. This is where things stopped being uneventful. The wood was not overly hard, but it was very tough and I could not shape it on the big belt sander because that is running too fast and the wood tended to gum up the belt and burn. So I have been stuck with using handheld tools. I thought that it is not a problem because I expected to do it quickly even so.
Of course it would not be nearly as long work if I have made ordinary rectangular handle and not this ergonomically shaped one. However I consider the handle shape to be an important, even defining, component of this design. Simplifying the handle shape in the name of saving time would in my opinion strip the product of its uniqueness and I see no point in hand-made completely generic knives.
I think that I could reduce this work significantly by working on multiple knives at once, cutting the outlines with band saw and rough shaping with the small belt sander. Due to confined space in my workshop I need some time for setting those two devices up so it is not always worth for a one-off action. But should I prepare say 20 handle scales in one go, It would certainly be worth it.
Before proceeding to finishing the handle I had to use my magic trick to improve the looks of the wood. That trick is called “ammonia fuming” and consists of putting the scales into a big jam-jar with a bit of ammonia solution and leave them in it overnight of for a few days, depending on what your goal is – the longer the wood is in the ammonia, the darker it will become.
In this specific instance I have left the wood sit directly in the ammonia solution, letting it to soak it up. It is also possible for example to only let the wood above the solution in the fumes (hence the name).
I have experimented in the past with multiple solution treatments and I have at my disposal a few such processes to alter the wood to warying degrees – from mild color change to actually making the wood compacted and a lot harder. The advantage of these methods over staining the wood with a dye is that the color change goes deep into the wood so it does not get scratched off. It also looks a lot more natural in my opinion.
However, to wrap up, this step took more time than I expected it to, but I think I can put it in “low hanging fruit” basket, because I expect working in bulk should reduce time here significantly and I already have the machinery necessary for that.