Results 1 to 2 of 2

Thread: FAQ - Want to know more about "Stupid Sharp Knives"? Look here!

  1. #1
    Join Date
    Sep 2008
    Location
    Bay Area, CA
    Posts
    7,696

    Question FAQ - Want to know more about "Stupid Sharp Knives"? Look here!


    Support BladeForums!
    Paid memberships don't see ads!
    This FAQ should help folks looking to learn a little more about "Stupid Sharp Knives". Information presented here will be updated as necessary.


    • What do YOU use your knives for?
    • What is a "Stupid Sharp" knife and how is one made?
    • Fine, so that’s how you make a Stupid Sharp knife. But WHY is it Stupid Sharp?
    • What steels do you like to work with and use? Why?
    • General Heat Treat info?
    • Why do you like putting chisel grinds on your knives?
    • Titanium knives with carbidized edge: What are they, why are you making them, and how are they made?
    • What are your preferred handle materials, and what design considerations go into your handles?
    • What are my sheathing options?
    • How do you sharpen a Stupid Sharp knife? How do I maintain my steel or carbidized Ti BT knives?
    • What are your standard models and pricing info for each?
    • Do you have a gallery where I can see examples of your work?
    • Do you have a website? What’s the best way to contact you?
    • What’s your current lead-time?
    • Do you think you might ever start doing small batch orders? If so, when and where should we look for a signup list?
    • Are you really not doing Busse mods anymore? Whom do you recommend I contact for mod work?



    • What do YOU use your knives for?

    Quote Originally Posted by Ban
    I mostly sleep with my knives Seriously though, I have at least a few knives under the pillow and within arm’s reach.

    I typically use my knives to open letters, boxes, and various packaging material. During work I use them to cut open caulking tubes, cardboard, and plastic bands.

    Off work, I carry a pikal. I keep it stupid sharp in case I should ever need to use it. It does not see much utility use unless I don't have any other cutting instruments around.

    Around the house, my kitchen knives see the most use with the typical food prep tasks.

    Out in the field I use a small fixed blade while fishing. And if I am lucky enough to shoot something while hunting, I use a BT4 to skin and clean my game.

    I also enjoy using some of my larger knives in cutting and chopping various media (2x4s, water bottles, manila rope). I like testing knife performance in the typical activities one might see in a cutting competition.

    • What is a "Stupid Sharp" knife and how is one made?

    Quote Originally Posted by Ban
    A friend once told me my knife was “so sharp, it’s Stupid!” We jokingly called it “Stupid Sharp,” and it just kinda stuck with me.

    The following is my usual process in making a Stupid Sharp knife:

    1) Profile the blank (I’m currently doing only stock removal, and I don’t see that changing any time soon)
    2) Drill holes for handles
    3) Clean up the surface of the blank
    4) Using a belt grinder, I grind the main bevels by progressing from a 36 grit belt to a 220 grit belt
    5) Carefully wrap the knife in stainless foil and triple fold the edges
    6) Heat treat the knife in an oven
    7) Plate quench the knives when the critical temperature is reached
    8) Let the knife cool to 150F, and then return knife to the oven for the first temper
    9) Remove knife, and let cool to room temperature
    10) Dip in liquid nitrogen filled cryo tank over night
    11) Finish second and third temper
    12) Clean up flats and ricasso from 80 to 120 grit
    13) Regrind the main bevel from 80 grit to 220 grit
    14) Roughly sharpen a V edge with a 120 grit, and refine edge up to a 320 grit
    15) Frosty satin the entire knife, etch logo and clean up the etch, clean up the spine and bevel the corners for a smooth spine
    16) Tape up the entire knife blade and ricasso, then clamp the blade tang to whatever handle material I’m using (usually micarta)
    17) Drill holes into the handle material using the clamped tang as a template, and scribe the outline of the tang onto the handle material
    18) Rough cut the handles on a bandsaw
    19) Pin and clamp handle set together and clean up the front of the handle slabs on the grinder
    20) Temporarily pin and glue the handle scales onto the tang, remove pins and shape the handle scales on the grinder
    21) Hand sand the handle scales to smooth out contours and finish
    22) Countersink the handle material
    23) Cut rivet tubing (oversize) with a hacksaw and grind tubing to size
    24) Flare tubing
    25) Grind entire spine one last time to clean up spine and ensure that the handle scales are flush with the tang
    26) Remove tape and apply Stupid Sharp edge (discussed further below)
    27) Clean entire knife with Simple Green, and pat dry. That’s all there is to it, now the Stupid Sharp Knife is done!

    • Fine, so that’s how you make a Stupid Sharp knife. But WHY is it Stupid Sharp?

    Quote Originally Posted by Ban
    The answer here is edge geometry. Effective and efficient knife performance absolutely depends on how well the geometry of a blade’s edge matches the task in which the knife will be employed.

    Edge geometry is a combination of both primary and secondary bevels. The primary bevel/grind forms the transition from the spine of the blade to the edge. Primary bevels are typically flat, hollow, convex, chisel, and/or a combination. Secondary bevels form the edge itself. These bevels are typically either V or convex. I prefer a convex edge to a V edge because I feel the convex edge is stronger, cuts better, and is easier to maintain. While both of these bevels should be appropriate for the knife’s intended use, how smoothly a primary bevel transitions into a secondary bevel is also a critical factor underlying cutting performance.

    There is no single perfect geometry that can be used in all applications. This is why matching the geometry to the task is crucial in getting the highest performance possible out of a knife. For instance, on a chopper, I generally prefer a robust full convex geometry (full convex grind into polished zero convex secondary) or full flat geometry (Full flat primary into a polished zero convex secondary). On medium-sized knives that might see a variety of uses, I generally prefer a gentle convex or full flat primary into a polished zero convex edge. On small knives, I often prefer a chisel grind that also transitions into a polished zero convex edge. But there are no hard and fast rules, and I have been known to experiment with geometry to test out performance characteristics

    • What steels do you like to work with and use? Why?

    Quote Originally Posted by Ban
    Carbon: CPM-M4, A2, D2, 10V, CPM-3V
    Stainless: AEB-L, M390, CPM-154, CPM-S35VN
    I also like Titanium (6Al-4V) knives with a carbide edge (further discussion below)

    Generally, I like A2 and M4 for working knives that’ll see field time. I like A2 for its toughness, ease of field touching-up, and decent wear resistance. CPM-M4 is a “high speed tool steel” and is some good stuff. It takes a fine edge, holds it like a pitbull, while remaining relatively tough. At higher RCs (63-64) it holds an edge for a looooong time. If it were more stainless, it would be my new favorite steel.

    In the kitchen, I’m a big fan of AEB-L or Titanium knives with carbide edges. AEB-L is very corrosion resistant, sharpens up easily, and holds a great edge for typical kitchen work. It’s actually designed as a razor blade steel. Its super fine grain structure allows it to take ultra sharp high polished edges that are ideal for push cuts. As for the titanium, I think the rust-proof nature combined with the decent working edge provided by the tungsten-carbide edge makes for an excellent every-day, negligible maintenance, kitchen user.

    Of course, new steels are always popping up, so I’m always experimenting with new stuff. While these are what I favor now, that might change down the line.

    • General Heat Treat info?

    Quote Originally Posted by Ban
    Heat treatment can vary with each knife, depending on steel used and the knife’s intended application. I generally heat treat my knives to around 59-61RC. Sometimes I’ll go higher if the steel performs better when harder (say, CPM-M4 heat treated to 63-64RC).

    • Why do you like putting chisel grinds on your knives?

    Quote Originally Posted by Ban
    I like chisel grinds on defensive blades because it allows me to get some very acute edge geometry. It also gives the appearance of nice and deep pronounced grind lines. With really thin stuff it is almost impossible to do flat grinds without significantly weakening the blade. Some argue that the chisel grind is easier to grind. Maybe...Maybe not... I don't really care. I prefer it for the above reason.

    • Titanium knives with carbidized edge: What are they, why are you making them, and how are they made?

    Quote Originally Posted by Ban
    Most people think of Titanium knives as novelty items that hold very little practical value unless you are a diver (recreational, professional/commercial, EOD, etc). For the most part it is true. Titanium is soft, relative to steel, and it won’t hold an edge like a good heat-treated steel blade will. However, to the average civilian user, titanium offers a high strength-to-weight ratio, superior corrosion resistance, and a tough and ductile edge (so chipping shouldn’t be an issue).

    Now, add some tungsten carbide to the mix and things start to look even more favorable for the titanium blade. Tungsten carbide is extremely hard; it’s a 9 in the Moh scale. A measurement of hardness on the Moh scale does not readily convert to the Rockwell C measurement most of us are familiar with, but I think it would be roughly in the mid 80's. If we apply a tungsten carbide edge to a titanium blade, we end up with a very low maintenance (effectively rustproof) piece of cutlery that can hold an edge just as well if not better than most quality steel edges. When a titanium blade is given a decent edge geometry, the carbide allows the titanium to hold a good edge and cut well.

    I’ve been able to slice slivers of paper easily with a polished carbidized titanium blade. While it could no longer easily and cleanly slice paper after about 25-30 cuts through cardboard, I know it could have kept cutting cardboard for much longer without a problem. I have had a few guys put their carbidized Ti knives through the ringer, and all of them are amazed at how well the edges hold up and how easy they are to maintain. One guy used his knife to cut and lay up a yard full of sod. Needless to say the knife was dull afterwards from all the sand and various other grits in the soil, but it required minimal work to bring the edge back to working order. People have reported their Ti knives functioning well in a variety of tasks, including food prep, working with wood, and taking apart abrasive packaging materials (e.g. cardboard).

    I, and others, have noticed that the carbidized edge will still cut very well even when it feels dull. In fact, the carbide edge can almost be considered self-sharpening: since the carbides are only applied to one side of the titanium blade edge, more carbide is exposed as the titanium wears away on the other side. This is similar to the self-sharpening phenomenon observed with the teeth of beavers. Actual sharpening of a carbidized titanium edge is very simple. See the sharpening and maintenance questions further along in this FAQ for more detail.

    So why carbidized Ti knives? I think these knives should work well in the kitchen, where they would be cutting relatively soft, non-abrasive, material (veggies, fruit, meat) in a wet and corrosive environment. Titanium’s superior corrosion resistance, coupled with the easily maintained carbide edge, makes these knives perfect for every day kitchen duty. I also suspect that carbidized Ti knives will catch on with the ultralight hiking/backpacking crowd. A strong, lightweight, and very low maintenance knife sounds ideal for the ultralight backpacker - someone who typically isn’t out there building log cabins or doing things that require a fine edge.

    How do I get the tungsten carbide onto the titanium? I currently use “The Carbidizer” from Travers Tool Co., Inc. Basically, this tungsten carbide applicator electronically embeds the carbides into the titanium. You can sort of think of it as a micro-weld, although no heat is generated. While I’m sure it’s not as fast or as powerful as the Rocklinizer, it does the job for me for now. I am currently looking into more powerful unit, which is supposed to be very close to the Rocklinizer for increased speed.



    continued in next post.
    Last edited by HikingMano; 08-02-2013 at 06:02 PM.

  2. #2
    Join Date
    Sep 2008
    Location
    Bay Area, CA
    Posts
    7,696
    • What are your preferred handle materials, and what design considerations go into your handles?

    Quote Originally Posted by Ban
    I like Micarta for knife handles. It is very durable, non-porous, great looking, and it just feels good in hand. I actually think Micarta feels warmer in-hand than G10. I have a preference for Oliven Linen Micarta in particular.

    To be added: handle design considerations

    • What are my sheathing options?

    Quote Originally Posted by Ban
    I can make kydex sheaths for you, generally drilled for Tek-loks. Inquire when you place an order or pick up a knife from me on the exchange.

    • How do you sharpen a Stupid Sharp knife? How do I maintain my steel or carbidized Ti BT knives?

    Quote Originally Posted by Ban
    Sharpening a Stupid Sharp knife (steel):

    Things you will need:
    Belt Grinder
    120 grit belt
    220 grit belt
    Coarse Scotchbrite belt
    Fine Scothbrite belt
    Leather Belt and Green Compound.

    Sharpen a V edge using the 120 grit belt, then follow it with a 220 grit belt. You want to knock off a majority of the shoulder.

    Use the coarse scotchbrite to continue knocking off the shoulder and slowly form the convex secondary bevel with alternating strokes. A coarse scotchbrite is good for this because it cuts fairly decently and - because it’s fairly unstructured - it naturally convexes the edge. Try doing a true V edge with one and you will see that it has the tendency to round the shoulder edges. Keep at it with the coarse scotchbrite until you are satisfied with the convex geometry. The geometry will vary from large knives to smaller knives, dependent on application, as discussed previously.

    NOTE: Be careful when doing this part of the sharpening because a decent amount of heat can be generated. Start off slow to get the hang of it and have some water handy to cool the blade. Dip the blade often to ensure you don’t overheat it. This is the slowest and also the most important step.

    Follow the above process with the fine scotchbrite belt.

    Finally, strop the hell out of it with the green compound saturated leather belt, and it should pop hair like nobody's business. I start off using a good amount of pressure to do the majority of the polishing. Then I slowly finesse the alternating strokes towards the end to prevent myself from increasing the angle and rolling over the edge.

    On average, it takes me 20-30mins to sharpen a new knife this way. But once it’s been set... I usually just have to hit it with the leather belt for a few seconds to retouch the blade.

    You can also simply strop the blade by hand if you don’t have a belt grinder. There are a ton of resources here at Bladeforums and around the web regarding sharpening of a convex blade, but feel free to contact me if you’d like some pointers. At some point, I hope to have one of the members here do a sharpening-by-hand video with one of my knives.



    Sharpening a carbidized titanium knife:

    As I touched upon in the Carbidized Ti knives FAQ question, the tungsten carbide is only applied to one side of the edge on the Ti knives. To sharpen the carbidized knife, you have merely to sharpen or strop the titanium side of the blade/edge to expose more carbides and thereby refresh the cutting edge. Do not sharpen the carbide side of the edge; you will only remove carbides from the titanium substrate.

    You should very rarely need to do more than strop the non-carbide side of the blade on a compound-loaded strop. In fact, before you even hit a strop, you should first steel the edge to straighten any rolls and align the edge. Often, a good steeling is all that’s really needed to return a carbidized Ti knife to a utility edge. The guy discussed above who sodded an entire yard with the help of a carbidized Ti necker, brought a working edge back to his knife with only a bit of steeling and a couple of passes on a compound-loaded strop. If you have and are adept with a belt grinder, the process is even easier… three seconds on a leather belt and the edge is brand new again.



    Last note on sharpening:

    If you have a really dull blade or just don’t want to deal with it, I offer free sharpening on all of my knives for the life of the knife. I will offer this service so long as I am able to grind.

    • What are your standard models and pricing info for each?

    Quote Originally Posted by Ban
    Large Knives
    Tigress
    Competition Chopper
    BT10
    BT7


    Medium Knives
    BT6
    BT4
    BT4 Recurve
    BT4 Variant
    BT4 Choiless
    BT4 Fat
    BT4 Recurve Clip
    Small Bowie


    Small Knives
    Mini Bowie
    Drop Point EDC
    Clip Point EDC
    Pikal
    La Griffe Pikal
    Hawkbill
    Wharnie


    Kitchen Knives
    Santoku
    Chef’s Knife
    Paring Knife
    Kitchen Cleaver
    Mini Santoku



    For specs and pricing, please refer to my website.

    • Do you have a gallery where I can see examples of your work?

    Quote Originally Posted by Ban
    Sure, check out these threads for starters. Searching the subforum itself for whatever interests you should also prove fruitful.

    http://www.bladeforums.com/forums/sh...467-Knife-Pics
    http://www.bladeforums.com/forums/sh...Ban-Tang-Knife
    http://www.bladeforums.com/forums/sh...nd-Gear-in-use

    • Do you have a website? What’s the best way to contact you?

    Quote Originally Posted by Ban
    Yes, I have a website: http://bantangknives.com. The best way to contact me is through the contact page on my website.

    • What’s your current lead-time?

    Quote Originally Posted by Ban
    In general, lead-time is about 3-6 months. HOWEVER, I often do batches by steel, so your order may be completed earlier or later than the estimated time frame depending on the steel you requested.

    • Do you think you might ever start doing small batch orders? If so, when and where should we look for a signup list?

    Quote Originally Posted by Ban
    As I transition into making knives full-time, you can expect to see more batches and special runs. While I do not have a sign-up process in place yet, I anticipate creating one once I start making knives full-time. You can check here, in my subforum, or on my website for announcements of upcoming runs and sign-up information.

    • Are you really not doing Busse mods anymore? Whom do you recommend I contact for mod work?

    Quote Originally Posted by Ban
    I am no longer accepting any Busse mod work because I am focusing on making my own knives. However, I hear that Norcalblacktail and Mrpink do some pretty awesome mod work along with sharpening






    Quote Originally Posted by Ban
    If you don’t find what you’re looking for in this FAQ, feel free to ask me general questions directly in this thread.

    If you have questions regarding an order, feel free to contact me directly through the contact page on my website
    Last edited by HikingMano; 10-02-2011 at 07:14 PM.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •