Saturday, November 29, 2014

The list......(and not the the Christmas kind).




It is very nearly time for us to go.... The big move is neigh, and swiftly approaches. I'm getting anxious.

We haven't chosen a place too live yet preferring, it seems, to trust in providence to guide us once we arrive. Where will we live? A slum-lord tenement, a junk heap, a palace, a tumble down shack in the woods (my preference, haha!). Will we even have running water?

Will we have electricity?



What tools do I bring? 

It must begin with an inventory, of course, as I'm not fully sure what hides in some of these boxes, anymore.



My precious, hand crafted tool boxes, built with love and care.... actually just drawers from my workbench. And plastic crates. And cardboard boxes. 


Users....




.... and not so much users.




Choosing the actual tools to bring is relatively easy. I'll bring what I use, of course, and that is a rather small percentage of the whole. More on that, in another post.




The real scary part comes with the need to pare down the sharpening stone selection. 

Oh the pain!! The tragedy!! How will I survive?!!




At $1/lb, I had better choose wisely. I've got another box full, too. So many experiments with locally found stones.

 I wonder what the next people living here will think? "What are all of these funny looking stones for? They are all flattened on one side..... Obviously paperweights!"



My excellent Baldor grinder will stay in storage, mostly thanks to a gift from a friend.



Brandon gave me this wonderful hand-crank grinder, and it has been sitting in the shop for a few months now. I've always wanted one of these, ever since reading Krenov's "A cabinet-makers notebook" almost 30 years ago. Man......time flies.


The Luther grinder, made with pride in the USA. I wonder what that means?


I've wanted one but never bought, mostly because those that you do see are so often trashed. Not this one. It's beautiful! Thanks Brandon!


Another reason that I didn't buy one is, well..... How well can it possibly work. Really.

When I was doing the spark testing of steel the other night, I tried to get some examples of Japanese steel to compare to. Taking the photos is an extremely awkward affair, with the tablet computer balanced in one hand, and the shrieking jerking grinder in the other. I don't want to completely shred one of my good kanna blades, so I dug this guy out of the "fettling" box. With a big chip out of the cutting edge, it will need to be visiting with Mr grinder anyway.




I don't know much about this kanna, other than its dirty. I've done a bit of hammering to clean up the top, but aside from that, nothing. Hirosada kanna and Cubs-Torasaburo post that I wrote a while ago explains what little I DO know about this kanna.





What? No spark pictures?

No sparks, almost none. WTF?!!

Well it turns out that this blade is made from some type of strange steel (a Togo steel variety, maybe), and based on the extreme lack of spark, I am guessing a type of high-speed tool steel. M2? I don't know much about that stuff yet, but I mean to learn. It's not your average high carbon steel, in any event.


So, back to the hand crank grinder..... It just eats this stuff up, no problem at all.




Even more interesting is that it is relatively slow going when using the Baldor electric bench grinder. It seems that the slower rotation of the hand-power grinder lets the grit of the wheel really work more effectively. The finish left is slightly rougher, too, which supports my theory. The individual grit particles get more opportunity to remove material.

Anyways, the gist of this is that, for some things, hand power really is faster. I'm learning that this is the case with using grinders and files to remove material when roughing out blades. Using files to hog off the bulk is faster than using the bench grinder. I guess that I need a bigger bench grinder, haha! 12" should do....220 volt...... Noise. $$$, yuck!



Another gift that will help me out when we get to Hawaii.


Sebastian has sent me a couple of saws to test out. He is studying hard, learning the Zen of saws.



There is some great new stuff here that isn't being explored anywhere else, in any degree (that I'm aware of).....





Almost all of my power tools are staying, and that's fine, mostly.

I will miss this old guy horribly. My old Delta 1160 tilt-top tablesaw. 



The dust collector I won't miss, though.


Another thing that I won't miss.



Ya' know, all of my woodworking life I wanted a huge workbench, something robust and thick. You need a big, heavy workbench to stand up to all of that planing and pushing, hammering, etc. I was so sick of flimsy, rattling workbenchs that don't work well, and are often too short on top of it all. Not this time. This time I was going to make a big sucker, one that would push back when I was planing, and not dissipate 1/2 of the force I was using to hammer a chisel into a piece of wood. 


Then I found the Japanese tools.


They pull.

I mostly work like one of those little, old, Japanese guys, sitting on the floor.

Too funny.






Thursday, November 27, 2014

Guesstimating carbon content using the "Spark Test".


I've been using old machinists metal working files for the cutting edges on my laminated blades. Of course this begs the question; What's in this stuff anyway?

It has long been thought that files are made from 1095 (0.95% Carbon) high carbon steel. I really wish that I had some 1095 to compare against, haha! What I DO have is a handful of old files and a grinder (a camera, too), so I'll start with what I've got.




I don't profess any sort of expertise at this, in fact, rather the contrary. Mostly, they just look like sparks, right? I've looked at the stream of sparks shooting aft of the grinder many a time, but this time I figured that if I took some pictures, I might be able to see something interesting. I'm gonna warn you now, this is a very monotonous series of photos that is only going to be of interest to a few people (kind of like the rest of this blog, haha!

It was dark, and I was outside anyways.



The first time I tried the spark test on this Heller file, I knew that I had better start paying close attention. This is an old 8" file, of unknown age. It was old, rusty and dull when I got it, so I can't attest to its value as a file or how hard it is.




Usually the sparks that get thrown off of high carbon steel look like long, red streamers. This file was different.


These sparks are short, red, frilly little things. Also, extremely numerous and active. Notice the many forks and branches, ending with the smallest of explosions. It's like the 4th of July!


The cameras exposure time means that these photos make it look like there are more sparks than you would see in real life. That is one thing that was always throwing me off  when comparing my results to what I was finding online. An actual volume of 2/3 to 1/2 might be more accurate.




These sparks feel soft, delicate, fuzzy.



Next is an old 12" Heller. Again, old, rusty, and dull.



I have read that sometimes the carbon content might be slightly lower in a large file like this one, but that doesn't appear to be the case here.




In real life at least, these sparks look the same (to my eye, that is).


This picture is more accurate in terms of the volume of sparks that I was seeing.


Volume, length, color and intensity, all are indicative. If you apply more pressure to the grinder, you get a longer spark trail and maybe a more fully developed spark, but then it gets hard for me to take the picture, so....



Now for something that I am more familiar with, a Nicholson 4-in-hand file. I've bought a bunch of these in the past and have never been particularly thrilled with their longevity. There they are handy to keep in the toolbox though.



A very different spark here. 


A more intense yellow, a longer stream, and not as much "activity". Fewer sparks, but what is there looks to be intense. Many of the tracers end with a little burst and a branching fork.


Notice how the sparks are bouncing off the tin wall? The spark stream is nearly 4x longer than the Heller files showed.


These sparks feel harsh, coarse.


Now.

I am probably guilty of promoting the same information, right or wrong, as everything that I've found written on the net, but again, we work with the tools we have. 

It has been said that in the old days, Nicholson files were made from a special type of C1095 high carbon steel that had1.22%(+/-) carbon, but since the '80's have been made from plain 'ol 1095. I've seen a number of old technical reference books online that list files as having a carbon content of anywhere from 1.20%-1.50%, and made from the same type of steel that taps and dies are made from. Just the other day I was reading a technical paper that specified using Vallorbe (Swiss) files, made with a 1.22% carbon steel.

I can say with absolutely NO certainty that certain files are made using a particular type of steel. What I am comfortable stating, is that the spark pattern from these Nicholson files is significantly different from the spark pattern from these old Heller files. I would also say that these particular files are NOT overwhelmingly hard.




How about an old Simmons "Red tang"?


This is my current favorite, and an absolute brute when it comes to chewing through metal. It's age is anyone's guess, and it's still sharp, though certainly not anywhere close to being new.


The sparks are starting to look familiar now.



They look nearly identical to those of the Heller files.





Another Simmons Red tang, this time a triangular tapered saw file.


Same (or near enough).







Now for something interesting.....

This rasp sprays a very impressive stream of yellow/red sparks, but there is almost no branching, explosions dots or dashes. It shows just a stream of large tracers that only fork at the ends (if at all).


This is one of those cheap China files that are pitifully soft, and absolutely worthless at removing metal.


The length of the stream is telling as well. See how the sparks are rebounding off of the back wall?


All right, I am beginning to associate long, intense, yellow/red, boring looking sparks with really crappy files. I have a few of these (I know a bargain when I see it!), and they all behave in a similar fashion. In my entire stash of miscellaneous metal, the only thing that I've found that compares to this spark pattern is some dead soft, iron tie wire used for wrapping rebar bundles (a great source for free 1/4" iron, BTW, and easy as hell to straighten!).

I think that this may be a case of.... Case hardened steel.




How about another cheap China file? 

Here is one of those super hard, little detail files that I bought at Wal-Mart, and am always raving about.


Short-ish red sparks, very active, with a multitude of branching, forks, and explosions.






Last one (for now)....

An "Oregon" brand chainaw file.


Can anyone else see the similarity here, or is it just me, haha!



Interestingly enough, the "Oregon" files are made in Switzerland....

.... By Vallorbe.


















Saturday, November 22, 2014

Correcting a "chippy" blade...





I've got this great little kanna blade, 48mm wide and I use it all of the time. It has one significant problem, however. Try though I might, the edge develops little micro-serrations in some areas, and don't want to come out, no matter how much I sharpen.






There is a procedure called "Killing the edge" that often works to correct for this jagged edge tendency. When it is time to re-sharpen, you first drag the edge over something hard. A glass works nicely but the side of your sharpening stone works well, too. What you are looking for is a clear, unbroken line of "bright" that runs the full length of the edge. This line of clean metal ensures that you are into the fresh stuff, and not fighting some remnant scratch or blemish.



Some blades are difficult no matter what you do.


Right now at least, I prefer very hard blades. Sometimes the blade can be TOO hard, though. I suspect that the degree of hardness that the blade is capable of carrying is partially due to the underlying grain structure of the steel. A fine grain structure will support a very hard edge, where a more coarse grain will tend to chip or fracture. The grain of the steel is established by the blacksmith, so we are stuck with that, being what it is.

A coarse grain structure needs be softer, in order to maintain its integrity. Tempering is the act of softening a blade, and is something that is well within the abilities of anyone. Easy stuff.

Really.



Preheat the oven (I start at 325°F).

****
Preheat the oven, because your oven runs full-bore until it reaches operating temperature. The high heat would potentially harm the blade, so.... Preheat.
****

Place the blade on something large and heavy/dense.



Some ovens control their heat more accurately than others, and the cast iron skillet (in this case) acts as a buffer. A little extra protection (and I was seasoning the skillet anyways, so I got to kill two birds with one stone!).

I cook the blade for 30-60 minutes. The actual tempering occurs nearly instantaneously, but extra time won't hurt anything and may contribute to a more thorough temper.


After the blade is done cooking, let it cool, then back to the stones.




Not good enough. 325°F didn't seem to change a thing.




Magnification concurs. The jagged edge remains.



So, back into the oven, this time at 350°F for another 30 minutes, then sharpen.


Better, so at least I might be on the right track, but not good enough yet.


I try again at 375°F...





Much better, smooth and straight. I don't want the blade any softer than necessary, so I'll stop here, for now.

This blades jagged tendencies appear to have vanished, but I'll reserve judgment for now.


The blade seems to sharpen up much better now, both easier and "sharper" feeling.


The kanna works better. Nothing to write home about, but definitely good performance. The true test will be in the longevity and ease of re-sharpening.



I could possibly get more work done if my assistant would stop napping on the tools, though.







I was taking a break from all of the carpentry obligations of the last month, by spending a little time in front of the forge (Yay!!!! Hammer time!!!). I am trying to salvage a sloppy laminated blade that I forged a few months ago. After a lot of massaging, I've ended up with something that is getting close to being a proper blade.





The heavy lifting in the shaping department has been taken up by the $Store sharpening stone. This is proving to be a favorite of mine, being soft enough to function as a waterstone, but hard enough to hold its shape without immediately dishing. And it cuts fast! Amazing performance for $1!


I only tempered this blade to 325°F , and it's WAY too hard for a kitchen knife. Harder than anything that I've ever used before, anyway.

Even worse..... Chipping at the edge.




I tried a second temper at 350°F, and it might have been sightly better, but still chipped pretty bad.


So.... I skipped right to 400°F.



375°F would've been perfect, haha! 20/20...

400°F didn't ruin it by any means, I just like to be more thorough about these things. You don't learn as much if you skip the proper steps, you know?



Unfortunately, this blade is a junker.


This little crack will propagate. I could take in the edge a bit.... Regrind the bevel...


The tip would need some work too. See how the end looks all fuzzy?



That's because the hard steel runs out and gets mixed in with the soft iron. The tip is too soft. The "fuzziness" is due to the way that the iron finished on the natural waterstone. The hard steel finishes to a near-mirror state. I could grind the tip back until I get to the better steel......


Even though the steel is now soft enough to *barely* form a burr, it still tends to chip out.

*hmmm*

I don't want to temper the blade any higher. It's soft enough already (actually it's a very practical, hard edge. I just want to see *how* hard I can make a knife!)....I am wondering if I could improve the steel structure through a series normalizing/grain reduction heats, at the forge, and do a new quench...... Re-shape the blade...... Sharpen again......

The new blade would only be, ohhhh.....a paring knife maybe?

I've already spent an unreasonable amount of time grinding out that uber-hard bastard, what's another hour?

Good practice.










Friday, November 7, 2014

More ura-dashi-----refinement

I guess that I had alluded to my writing a post on performing ura-dashi on chisels....... But I'm not. Yet. What I have right now is a kanna blade that is causing me some difficulties, so I took some photos of the process. Lots of photos.

Tapping out the back hollow (ura-dashi) on Japanese plane blades, chisel blades, knife blades and carving tools....... Everything takes a hit. Ura-dashi is faster than just grinding away at the stones, preserves the all-important steel hagane, and also serves to maintain a proper fit between kanna blade and dai. And it's fun!

Ura-dashi is a necessary skill to learn if you want to get the best performance from these tools, but it has a reputation for being a process fraught with danger. It's scary the first few times, but (and I can't stress this enough) get the right hammer and it's a piece of cake.



I got this old kanna recently that showed evidence of having had some pretty serious work done to the bevel. It looked as though the blade had chipped out very heavily, necessitating a more extreme session of ura-dashi than typical. Rather than the edge coming to a point, it ended abruptly at an approximately 3mm blunt tip.

When a blade requires very forceful measures to correct it for warp, twist, or has had an unfortunate encounter with a nail/rock/concrete floor, the pros will often grind the edge back a few millimeters before performing ura-dashi. This gives more support to the steel, reducing the possibility of making the damage even worse. This looked like one of those cases.

Things are coming along nicely. I have already corrected the slightly mushroomed head of the main blade, and gotten a good start on forming a new bevel. This is a 65mm blade, BTW.





I was able to hammer the upper portion of the blade back into shape, but the perimeter was starting to fragment, so I had to resort to filing a decorative chamfer. Frustratingly close to the original profile, but no cigar.



The main blade had been cut back so severely, that the secondary blade needed amputation as well (or possibly the damage was so bad that BOTH blades needed shortening, yikes!). So, ura-dashi for the osae-gane, too.



This is perfect, to my eye.


You can't make a silk purse from a sows ear, as they say. This osae-gane was well forged, and the urasuki was nicely ground. I just try to keep things looking "proper". Sometimes you get lucky......



....and sometimes you don't (get lucky, that is). This is the main blade.


The tiniest remnant of the original damage. The crack only became apparent after starting the back-flattening process. What I *really* don't like is that the crack runs longitudinal to the length of the blade. It is possible that this will propagate right up the middle and make the blade unsalvageable, but my fingers are crossed.


I grind the blade back another 3mm, about 1mm past the visible damage.



Right back to where I started, haha!



Hopefully that gets all of it. I won't know until I've completely finished sharpening the blade



More ura-dashi.

There is a bit of a push/pull interaction going on during this process, particularly in such an extreme case as this. The hard steel hagane is.... hard, and doesn't bend (well, it bends but it doesn't retain the bend. It is highly resilient and resists permanent deformation). The actual bending is due to the soft iron being bent and displaced/deformed by the hammer blows. The blade was made using a relatively hard wrought iron and it feels a little stiff. This isn't the easiest blade for ura-dashi. Maybe the steel is very stiff, too?

You hammer the bevel, displacing and expanding the iron, causing the cutting edge to be deformed downward. This induces tension into the blade.

The little squiggle to the right of center isn't the crack, it's a piece of lint.


I check for flatness using a #1000 grit diamond stone. You can see the barest hint of the flat beginning to form at the bottom edge.




I do 90% of ura-dashi using just a tiny (8 oz?) tack hammer, but this blade calls for the big gun!


A 32oz ball pein hammer is nearly the LAST type of hammer that I would choose for this process, but it is close to hand. A nice funate pattern genno would be perfect for this. Someday....



I am trying to achieve a perfectly straight, flat, land (the ura-ba, I think) at the edge.


This is looking good. It is a beginning.


The problem is that there is a lot of material yet to be removed from the bevel. I figure that doing this process in stages will minimize the stresses on the already stressed-out steel. Some of the pros advocate an even slower pace, and do just a little bit of ura-dashi over the course of days or weeks. I'm patient, but.....

Back to the bevel then. Heavy files remove the iron quickly.



And here is where the push-me, pull-you comes into play. The ura-ba was looking perfect before setting the bevel, but now the line has become uneven.




I target a very specific region to focus my attention on. Only strike where needed. Don't hit the steel part, only the iron (I know you've heard that one before). Strike heavily towards the base of the bevel to affect a broad area, lighter and closer to the cutting edge for a more localized effect.



The ura-ba is more even in width, but now there is a new condition to address. The corners are no longer making contact with the evidenc accentuated by the different directions of the scratch patterns.


I switch up directions occasionally, so the scratches act as an reference.


Back to my usual hammer. Small strikes, as close to the corners as I dare.



Magic!


There is a small spot at the far right that is still not touching fully, but that will come out as I finish.


A note: As I look at all of these photos, I guess that it should be clarified that I am right handed. I hold the blade in my left hand, with the head of the blade close to me, the bevel of the blade furthest away. Nothing weird or original about my posture, pretty typical. I would take a picture, but I only have two hands (*sigh*..... If only.....).

When tapping, I keep my hammer arm elbow tight to my side, for a controlled/restrictive movement. If your elbow is flapping around, your accuracy goes out the window.



The blade is now shorter and thicker than it was, so the blade is now a tight fit in the dai. There had been a paper spacer...... Gone now.



There is still a long way to go before the blade reaches the proper position.


It's time to actually sharpen the blade, but before I do that, I take a few measurements to see if I need to remove more material from one side of the blade, or the other.



It looks like I will be favoring the left when I sharpen this guy. The left is closer to the surface, and would be the first side to protrude, all things being equal. I want the blade to protrude evenly of course so I will try to remove more material from the left of the blade.


I do that by applying more pressure to the left side as I grind away at this thing.


I've been singing the praises of this sandpaper, but got the name wrong, haha. I was calling it 3X (actually a Norton product, and a good one, too), but it is 3M sandblaster. This is very tough stuff, and lasts an incredibly long amount of time.


This single piece has been used on a number of blades, and doesn't feel sharp at all. It still cuts, though.


That dust is mostly iron. About 50% of the grit is missing by now, and it's long overdue for replacement. If you sweep off the paper occasionally, it cuts faster.


Almost there.


After the #60 grit sandpaper, I jump to a #400 diamond stone.


A full, even width bevel.


And one last time, I check the back side for flatness.


It looks good.


Well, maybe just one more.....


And one thing to note about the blade in the picture. The line of hagane is flat and even. If I had just ground down the blade without performing ura-dashi, the line would be thick in the middle, tapering to nothing at the corners.

 Remember the chisel in the last post?



And, lest you think that all I do is sharpen tools.....


We have rebuilt almost our entire house, with the exception of one small area. The dreaded bathroom.



Just in time for us to move, haha!


I need a shower.