WIP - Harpoon Bowie

Erin Burke

Well-Known Member
It's probably not fair to call this a Work In Progress (WIP) thread, as this knife was completed last year... but Lord knows I took enough pictures, so here we go.

SKETCH
My knives always start out as a pencil sketch… and my day job has me sitting at a desk for 10-hours stretches, providing me ample opportunity to sit down with a sheet of paper. All sketches are drawn free-hand, then refined and cleaned-up using various French curves. If I am building a folder, the pencil sketch will be brought into AutoCAD as a template… but that’s a whole different WIP.

This knife is a fixed blade, and started life looking something like this:

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It’s a fairly straight-forward design with maybe a couple things worth commenting on.
• I did not draw a plunge on the sketch. Most of the knives that I make nowadays are plunge-less, with a few exceptions. This knife is not one of the exceptions.
• There are three holes drawn in the blade. This is 99.9% an aesthetic feature. When I drew up this sketch, I felt like the broad expanse of the plunge-less, flat-ground primary bevel seemed a bit sparse. I used the three-hole accent on a little pocket-Bowie a few years ago, and just liked how it looked… so the feature made its way into this design as well.


PHOTO #1
I am currently a stock removal maker. I own an anvil… it sits in my shed. Sometimes, late at night – when the moon is high and the birds are asleep – I like to think about forges & san mai, presses & integrals… then I grab a chunk of steel from Aldo, Don or Kelly and turn it to dust. Shortly thereafter my wife comes downstairs all bleary-eyed and asks “the moon is high and birds are asleep... why are you making so much noise?”. She does not understand.

I make many photocopies of my original sketch. Here is one glued to a bar of Aldo’s 1/4” W2. I use 3M 77 spray adhesive, and hate it. It doesn’t hold up well to grinding heat and the cap is always plugged… but until a better solution presents itself, I’ll just keep using it… and keep complaining.

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PHOTO #2
My shop is tiny (about 9’x21’) and so, therefore, are my tools. This is my wall-mounted porta-band. With it, I cut pieces of steel into smaller pieces of steel. Sometimes the smaller pieces of steel are vaguely more knife-shaped than the source pieces.

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Fun side note: My wife hardly ever comes into the shop unless she is leaving the house and wants me to come upstairs to watch the kids. She is a professional photographer… and in the past I have tried {unsuccessfully} to get her to document my process. I argued that these photos, in the future, will aid the biographers in their research to develop an authentic feel for the TV movie. She often is unimpressed by the logic of my arguments. All that to say, I have to take pictures of myself for these WIPs. These are a lot like my Facebook selfies… only without the duck-face. And I had to buy one of THESE THINGS to hang my iPhone from the ceiling.


PHOTO #3

Admission: I'm not above sucking it in for a photo.
Sad realization: this is me sucking it in.

Here I am cleaning up the edge profile with a worn 36-grit blue zirc belt on the KMG.

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Note: This is a good way to destroy a white t-shirt.



PHOTO #4
And this was the result. Feel free to hold your applause until later.

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So I had the brilliant idea to track the weight of this "knife" as I go. As you can see, my top-of-the-line Harbor Freight scale can display weights in grams, ounces or pounds. I chose grams; I figure "if it's good enough for drug dealers, it's good enough for me." This blank is starting out at 1031grams.
 
PHOTO #5
As I get older I have come to the realization that oftentimes in life, things do not always line up the way they should; sometimes your cheeseburger comes without cheese, sometimes the home-button on your newly refurbished iPhone is loose, and sometimes your steel arrives bent… all problems that can be solved with a big hammer…

… I mean, except for the cheeseburger thing.

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PHOTO #6
I have nothing interesting to say about this photo. The {recently flattened} bar of steel has been painted with blue Dykem, and is being scribed with some guide-lines for establishing distal taper. Also, I bite my fingernails.

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PHOTO #7
This photo, on the other hand, is full of interesting things to talk about. The info will be especially valuable in bullet form:
• Blade blank: Someone wise once said that it’s easiest to start grinding distal tapers by establishing a hollow down the center of the blade… I think it was Confucius, or maybe Pauly Shore. Here I have scribed a grind line on each side of the blank so my hollows are symmetrical. This is probably a bit more anal than is necessary.
• KMG grinder with 8” wheel: Really, just check out that paint job. It’s been scientifically proven that a grinder with slick paint will perform significantly better than one with no motor. My experience backs this up.
• Super-Cheap BORA7 36-Grit belt: This was my first time using these belts. Meh.
• Welding magnet: Keeps fingers from burning off. Very useful.
• Brush: For brushing things. Probably the single-most important tool in my shop. If you are a knife-maker, you should have 10 of these {in various sizes} laying around your workspace. Even then, it will still take you 15-minutes to find one when you need it.

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PHOTO #8
Here I am grinding the starter groove for establishing the distal taper. In case you’re wondering, my t-shirt depicts a humanoid robotic form constructed entirely of Craftsman power tools.

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PHOTO #9
Remember that welding magnet? Well here you go.
Now may also be a good time to mention shop safety... respirator to keep my lungs from turning black, safety glasses to keep my eyes from attracting shrapnel, baseball cap to keep {what's left of} my hair from catching on fire, and a fire extinguisher to keep everything else from burning down. Keep safe.

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Only 118 more photos to go.
 
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Fun side note: "My wife hardly ever comes into the shop unless she is leaving the house"

Funny my wife almost never comes to my shop.

Hurry Up I'm hooked.
 
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All I can say is you are doing great developing a grinding muscle/rest.
Mine works great for those bevel grinds!

I am glued to see your finished product!
 
I have the same thing , my wife never comes to the shop unless she's leaving , I will be working on something and look up and she is standing there , about gives ya a heart attack!
 
These next three photos show the results of the distal tapering.

PHOTO #10

First, for a little math… we take a look at the scales again.

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That’s 811g folks. If you’ll remember from yesterday, we started at 1031g… so we have a weight loss of 220g or 21%. If we were to put this in terms of me dieting (which Laurence’s grinding rest comment has me consideringI see you there post number seven), I would have lost about 46lbs and now weigh in at a cool 174lbs. Ironically, I think this is nearly the exact weight my doctor say somebody my height should weigh.


PHOTOS #11 & #12

To put the taper in perspective, these next two shots show the thickness of the blank at the guard and near the tip. They are fairly self-explanatory.

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I will, however, take this opportunity to sing the praises of Harbor Freight digital calipers. They’re cheap, and they work. These have been going strong for half a decade… for $20. They WILL start to lose zero as the battery gets low, so keep spares on hand.


PHOTO #13

Here I’m breaking the edge with a used 36-grit belt… the same BORA7 belt from earlier. I’m not sure whether there is any real value in doing this edge-down. I think there is a perception that breaking that sharp corner in an edge-up orientation would strip grit from the belt… but I don’t know that it really makes any difference. If I was really trying to conserve the belt here, I’d be doing this on a contact wheel rather than the platen.

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I forgot to get a photo of the actual bevel-grinding process. It was done edge-up on the work rest with a push stick to apply pressure.

But wait!... Here’s a short, low-quality Youtube video
[video=youtube_share;-pphCY8U4rI]http://youtu.be/-pphCY8U4rI[/video]



PHOTO #14

Let’s check those scales again.

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We are now at 613g… that’s down 198g (or 19%) from our previous weigh-in. In total, we have lost 418g (~41%) so far. So how much would I weigh now?... a svelt 131 pounds. This brings back memories of junior high. I wore turtle-neck shirts year-round because I thought my neck was freakishly long. Turns out, I was just a weird skinny kid wearing turtle-neck shirts.


PHOTO #15

This is where I left the edge thickness.

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Note: I actually ended up taking my bevel even thinner prior to HT, but I didn’t get a photo.
 
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PHOTOS #16 & #17

Fancy science people have shown that facial symmetry has a significant effect on the perceived attractiveness of humans. (Don’t believe me?... check Wikipedia. That’s where all the fancy science people hang out.)

Of what importance is symmetry in regards to knifemaking? I don’t know…
… but here is the part of the WIP where I cut some blade templates out of galvanized flashing material.

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Sometimes I get annoyed by the time it takes to grind out a template – like 5 minutes or something – but, as you can see from the photo above, it’s supes handy for scribing lines evenly on both sides of the blade. :thumbup:


PHOTO #18

More weight loss. Profile adjusted and a bit more bevel grinding. That's 94 more grams removed. We're at almost exactly 50% the weight of the original rough-profiled blank… and I’m 110lbs and light-headed. At this point, the blank was still a bit heavier toward the tip than I’d prefer.

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Note: This photo – and several subsequent ones – are smaller than the previous pictures because of Steve Jobs. And don’t quote me on this, but I think ObamaCare may also be partially to blame. :biggrin::9:


PHOTO #19 & #20

Doh! I forgot to drill these holes while the blank was still square… but nothing we can’t take care of with a center-punch and some shims.
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It may appear, from the image above, that I am free-handing the work-piece. This is not safe… and I’m pretty sure that I had a stop-clamp somewhere to keep the blade from helicoptering. I’m also pretty sure that helicoptering is a word… since autocorrect didn’t flag it. Pictures like this make me feel like a have a real shop.
 
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Keep up the GREAT work - I'm following this WIP. Good detail in captions to photos and they do help me follow.

Ken H
 
Very interesting seeing the weight differences as you progress. I never really thought about this until now.

I also enjoy the humor you have presented in this thread so far. Makes for a fun read, and I hate reading. :biggrin:
 
I’ve had all of these photos just sitting around collecting dust since last year... and because of this I thought it would be a simple task to turn them into a WIP. To tell the truth, remembering what was going on and accurately captioning the images is more than half the battle. Also more-than-half-the-battle is sitting here in front of the computer without getting distracted by Youtube videos of cats, babies or rainbows {double}. Actually taking the photos was, at most, 5/16ths of the battle. It adds up to a lot… probably more than math really allows… but nobody ever said battles were easy.

PHOTO #21

When I bought my Nielsen disc system, I ordered a flat disc and (because everyone else was doing it) one with a 1-degee taper. For a long time, the tapered disc seemed to be of little value, and just sat in a drawer. These days, while I still don't use it often, I’ve found it to be handy for cleaning up the inside surfaces of flat-ground recurves. Now, I almost wish that Rod made a disc with a 2-degree taper. :what!:
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In this photo I'm spreading some 3M Feathering Adhesive on the disc. Back in the day, I used to use Duro All Purpose Spray Adhesive for this, but hated it much like I hate the 3M 77 stuff. The feathering adhesive is so much better… an improvement similar in degree to Tennant vs. Eccleston.


PHOTO #22

Cleaning burrs from the holes that I drilled a few steps ago. I'm just doing a quick pass here, but I should have put on my respirator and eye protection anyway. I also should have moved the garbage can to avoid catching sparks. Disc is turning counter-clockwise in this photo. When I work the other side of the blade, I reverse the rotation and do a mirror version of the exact same thing.
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In this photo I am using the 1-degree taper referenced above to gain more access to the inside radius of the recurve. I am also wearing a polo shirt.


PHOTO #23

While reviewing these pictures, I noticed that I had inverted numbering on the next three photos. Problem corrected! Chronology restored.

In this image, I have just done some clean-up grinding of the tang profile. Prior to this, the tang was still a wide slab of 1/4” steel. It is a bit more dainty now… though still quite thick. I could tell you that the grinding was done with a used 36-grit blue Zirc on the flat platen with the work rest in place… or you could just look at the photo.
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PHOTO #24

Because this knife will be "plunge-less", I need to bevel the tang to match up with the blade. This will allow me to fit the guard eventually. Here I have scribed lines where I'd like to grind to. The scribe lines were established with a height-gauge on a {filthy} granite surface plate. Really… somebody should wipe down that surface plate.
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I ground to the lines on the KMG flat platen using the same used 36-grit blue zirc belt from earlier... but forgot to photograph it.


PHOTO #25

Back to the disc grinder to clean up the tang transition and the tip (shown here). I switched to the flat disc to ensure that things end up FLAT and symmetrical toward the tip. Note the respirator and safety glasses this time… though I still haven't moved the garbage can. The disc would be turning clockwise in this photo.

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Additional Comments aka “Things of Potential Interest… or Not”:
• My disc grinder is built on a 2hp 3-phase motor. The setup is driven by the same KBAC-27D variable frequency drive that powers my belt grinder. You can see the incoming power dropping down from the ceiling.
• I use blue painters tape all of the time… the wide stuff. You’ve seen it in earlier photos, and you’ll see it much more in the photos that follow.
• There’s a huge sheet of 0.02” 6AL-4V titanium under the bench. You can see one small piece cut out of the upper-left corner that I used on THIS KNIFE. Face-milling the Ti to the correct thickness was such a pain that I haven’t touched it since. The moral of the story is: "Always buy the correct thickness of titanium for your project... even if you can get a bigger piece for cheaper." Here’s an old photo from when the sheet was brand new.
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PHOTO #26

At this point I’m getting close to being ready to start the heat treat. Because I’m shooting for a hamon (differential HT) on this blade, there’s still one area that I need to address with some high-velocity abrasives… the false-edge.

This photo shows where I have used my handy-dandy galvanized template (which still has a paper template glued to it) to scribe the termination of the false-edge.
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I don’t know how others feel about them; but to me, false-edges were hard to figure out… especially a raised edge like this. I am, by no means, an expert… but here are some things I consider:
• Aesthetically, the ridge line where the primary bevel and false edge meet should be a pleasing continuation of the arc established by the spine of the blade (behind the false edge). This helps the lines of the blade flow and keeps the false edge from looking like an interruption. This is why the scribed ridge line is important.
• The false edge should be sharp and usable. I like the idea of a zero-degree grind here (no secondary edge bevel). Visually, it is very helpful to have a defined centerline scribed along the spine of the blade when grinding this.
• When grinding a primary bevel, the grind becomes more stable as you progress, because the wider bevel is easier to index against the belt. The bevel for a false edge is NOT very wide… and (for me) it is not always easy to “feel” the angle correctly when approaching the belt. BUT because you now have two defined lines to target with your grind (the ridge and the center of the spine), it is important that you hit this angle correctly EVERY TIME. Fortunately for me, there is a handy tool for assisting with this… Fred Rowe’s Bubble Jig. I’m not affiliated with Fred in any way other than owning one of his jigs (one of the older ones… before they had a slick paint-job) and being a satisfied customer. I don’t have any videos of me grinding with the jig, but in the photo above you can also see a scribed line perpendicular to the false edge grind for placement.


PHOTO #27

More weight loss... though not all of it is sexy. Most of this drop came from profiling the tang, and is more like having a large tumor removed than slimming down for a marathon. There was some sexy weight loss at the false-edge though. Another 214g down. We're now at 305g and have slimmed to 30% of the original rough blank weight.

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If we were still tracking my weight, I’d be 65lbs and look like that girl from “The OC”… remember that show?... yeah, me neither.



How about we finish up this update with some photos of something really HOT?...

… No… not the other girl from “The OC”.


PHOTO #28

Normalize (nor-mal-ize): to bring (someone or something) back to a usual or expected state or condition. To make normal.

If normal means crawling into a blazing furnace repeatedly, I’ll pass.

You'll note the two 1/2" plates of steel sitting in the bottom of the kiln that I use for a thermal mass.
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I really only meant to run four cycles... but somehow messed up and ended up with one at 1440 AND one at 1340 instead of a single 1400-ish. I’m hip and just roll with it. I am hip right?... guys?...
… is anyone there?


PHOTO #29

This picture is just fun.
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Cooling racks from Tracy at USA Knifemaker. I have one of these inside the kiln as well… very handy.
 
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