Any Knappers want to try Borosilicate glass?

[silicosys4]

Hi,
I've got a project in mind. I am interested in trying to make or have made some knapped knife blades out of colored borosilicate glass.
Lampworking borosilicate glass is a hobby of mine and I'm thinking about making up a couple of "blanks" I guess you could call them.
I'm looking for someone who is knowledgeable in flintknapping to offer me some knowledge as far as what dimensions I need to look at for blanks.
From what I've seen it takes quiet a bit more material to start with that I'd have thought...a pretty large chunk of flint for a modest knife. I'm limited with my equipment to probably fist size blanks, maybe a little bigger.

I would basically select different colored glass, then use a torch to melt them together, achieving what I think would be anything from a "damascus" look to marbling, depending on the colors used and how much I work them and blend them.

Any experienced knappers want to take a blank or two on, see how it works for them, and provide some feedback? You can keep it, and the blade you make. I just want to know how feasible my idea is, and if there is any market potential for knapped glass knife blades with various colors and patterns.

I have a pretty good selection of colors to choose from, opaques and translucents, everything from loud crayon colors to dark greys, blues, and amber earthtones.

I'm interested in finding out such things as how the annealing of the glass affects the knapping, how different colors react to knapping, etc...

Here's the only example I could find online, that is made using a single color green opaque glass blade





Thanks

 

[hso]

I don't knap, but if you don't get any takers I can get it into the hands of experience knappers. If you can provide the material by Oct. 10 I'll be where there will be at least one person available to give it a try. Shoot for something in the old style Coke bottle base thickness for one of them.

 

[mole]

If you can get the ball of glass into the hands of someone with a diamond stone saw then they can slice it up into several blanks. 1/4" thick works well. If you slab it into preforms then the width and length won't be much smaller than the size you cut it.

You need to make sure that were the two pieces of glass melt together that there are no air bubbles. A buddy of mine uses a kiln to melt his glass together and the composite piece works fine.

As far as a market...not in my area. Nature provides much more beautiful pieces of stone than man ever could and people just don't realize how much time and effort goes into the piece. People today want stuff cheap. The Internet market might be feasible---I have no idea.

 

[silicosys4]

I can pretty much make any shape/thickness, I was just thinking "blob" because that's what I have seen people start with when I've seen Knapping done....an irregular boulder/rock. I can make a coke bottle thickness flat sheet pretty easily, that would be great! That would save a lot of time and material from what I was picturing

HSO, do you have any colors you'd prefer?

 

[hso]

Nope

Whatever you'd like to see done.

 

[silicosys4]

Ok, I came up with a few blanks. Do these look like something that could be knapped? Or do they need to be different, dimensionally? They are each about 0.25" thick.
Thanks!

 

[silicosys4]

Side view

 

[mole]

They all look workable to me. Nice colors too.

John

 

[hso]

Sure, those are fine for size.

 

[craftsman]

I have no idea how much a table is at a knife show, but there's one coming up near here soon - weekeknd event. I'd bet half your sales that if you had a set of these for sale, you could sell them there. Or just go to the show, and one of the vendors would likely buy it from you. Beautiful work! I don't knap (I nap! LOL), but would love to learn how.

 

[jerkface11]

I think one of the knife vendors at the Wanamachers gunshow in Tulsa had knives with borosilicate blades.

 

[craftsman]

http://gunshowtrader.com/gun-shows/lehigh-valley-knife-show/

Let me know if anyone will be going and when you'll be there, I'll see if I can meet up with you. I'll most likely be hanging out (if they'll be there) at the AKTA demo outside with Michael "Rebel" Jordan, and/or Joe "Brokenfeather" Darrah. $6 per day admission. $60 per table if you're selling. Sam, kids, escorted by parent, under 13 = FREE!

 

[silicosys4]

Well, as it turns out, good knappers are hard to find, went to a rock and gem show yesterday hoping to find someone skilled who would play around with a blank, and no luck.
I know they are out there, though.

 

[Sam1911]

Oh, heck yes!!! We'd love to come out!

 

[craftsman]

SAM1911, I'll get on Facebook when I get home, and find out if Joe and Michael will be there this year. Will you be selling? or just going to check it out to see what the crouds are like, and maybe set up a table there next year?

 

[Sam1911]

If I had the time to make enough knives to fill a table, I sure would love to. But...I'm time poor in an extreme way. I'll just be looking!

 

[craftsman]

Here's a current list of vendors for this year. Waiting to hear back from Brokenfeather. http://www.paknifeshow.com/

 

[CWL]

Are 1/4" blanks thick enough? Does this leave any room for error?

I've watched people knapp knife blades and arrowheads before. What I can remember is that the gentleman started with a piece of flint (or was it chert) the size of a grapefruit and ended up with a blade about 2/3'rds the length of the one in the first post.


Add: -or is it because of the many flaws and occlusions in natural material?
I found this pretty cool site with knapped blades, mostly natural but also man-made glass http://stonebladeart.com/Archives.HTML

 

[craftsman]

FYI - There will be no official representation by the AKTA at the Lehigh Valley Knife Show 2014. But anyone attending that wants to bring a backstop and setup outside, as they have done in the past, be sure to clear it with the organizers. This is always a crowd pleaser and a good way to interest newbies.

 

[Sam1911]

There will be no official representation by the AKTA at the Lehigh Valley Knife Show 2014. But anyone attending that wants to bring a backstop and setup outside, as they have done in the past, be sure to clear it with the organizers. This is always a crowd pleaser and a good way to interest newbies.

Oh? Did that fall through, or just not official yet, or what? The boys wanted to see if they could get some more pointers.

 

[Flintknapper]

Ok, I came up with a few blanks. Do these look like something that could be knapped? Or do they need to be different, dimensionally? They are each about 0.25" thick.
Thanks!

1/4" to 5/16" is fine for thickness. The round edges are a hinderence, if you can make them into slabs (flat surfaces and square edges) it will be easier to knapp.

When pressure flaking you begin the process by alternate flaking the edge(s), its easier to start with a flat surface (on the edge). The round edge is not a big challenge (you could simply percussion a starting flake) but IF you can just as easily make them square, then do so.

As you can imagine 'knapping' is simply material 'reduction' so by default you will lose thickness, length and width with each 'pass'. Thickness is easier to control than width.

Unless you want an unnatural looking 'flat' blade (a lenticular shape is desired) then multiple passes are required. The knife you have pictured in your first post appears to be a 'FOG' (Flake Over Grinding) where the piece is first ground to shape and dimension, then a single pass (usually) is made to establish whatever flake pattern you desire.

A piece knapped from a slab will likely lose 1/4 to 1/3 of its width, length can be controlled a little bit better if you thin the tip quickly. The quality of the glass will be the limiting factor. It must NOT have air bubbles (especially out near the center). Bubbles will result in 'steps' that can be hard to remove with successive passes.

If the blending of colors does not effect the 'tensile' of the glass (the piece needs to be as homogeneous as possible) then I see no problem with it. Depending upon the heat treatment, the glass might take on a dull look with each flake scar produced. Glass is funny stuff.

Ask any knapper who has a lot experience with Obsidian. Some of it is brittle (hard to push a flake without it crushing or producing stepped hinges) and some is wonderfully reliable (almost plastic in work-ability). Same can be true of man made glass. Fiber Optic is great for example.

 

[craftsman]

SAM1911, Not sure, but I did not see Joe's name on the list of vendors at 2 weeks before the date, so I messaged him on Facebook. He may be working (his new job is a bit more structured, so he has less flexibility than before), or just not interested in doing a 2 hour drive up here for it.

I don't have a pickup truck, so I have not yet built a backstop in my yard for this stuff (need supplies from Lowes or H.D. )

I do have these up ...
http://www.instructables.com/id/Tripod-Easel-Support-for-Knife-and-Tomahawk-Throwi/
http://www.instructables.com/id/Safety-backstop-for-a-pellet-rifles-pellet-trap/

 

[silicosys4]

Thanks to the link by CWL, looks like I will have either some pictures of blades to post in a week or two, or some input on what to do different.
Will post more info as it comes

 

[craftsman]

I downloaded the PDF of Knapping links. This looks like a lot to learn, but a lot of fun.

I'll add the knapping tools to my "Christmas" list.

 

[USAF_Vet]

One of my coworkers is an experienced knapper. The obsidian blade he showed me was drool worthy. This guys passions are black powder, blacksmithing and flint/ glass knapping. If you want, I'll get a piece or three into his hands and see what he can do. He is at some mountain man rendezvous this week, so I won't even be able to ask him til he gets back.