knapping flints from scratch

[armymedic.2]

i knap my own arrow heads, and was thinking of doing my gn flints too. question is, do i have to use a certain type of flint, or is anything ok. i ussually use heat treated novaclite for my arrow heads. sometimes obsidian, which would be too fragile i know. got some chunks left over that would make good gun flints if i could use em for that.

 

[J.D.]

I'm not an expert knapper, by any stretch of the imagination, but any good quaility chert will make good gunflints. However, I would not use heat treated chert. Heat treating helps the chert to break easier; breaking easily is an undesirable trait in gunflints.

Use nearly any good, non heat treated flint and you should be ok.

 

[tg]

Give it a try, most Quartz type stones will spark, don't worry if the don't look like the English ones you see in the catalogs you can knock spauls off of smaller pieces than it takes to strike the long flakes and break them into lengths,If you do arrow heads then you know the geometry and basics of stone knaping and will do fine making useable guns spauls or flints, often you can get three sides off a good spaul.

 

[mudd turtle]

Obsidian is volcanic glass- I have never seen glass make sparks.Mudd Turtle

 

[Rebel]

It does. I have some local obsidian here and put a piece in the jaws of my flinter. It sparked but broke on the first try. It does spark though.

 

[tg]

"It does. I have some local obsidian here and put a piece in the jaws of my flinter. It sparked but broke on the first try. It does spark though"

I'll second the notion, I have tried it several times and it made the gun go boom I can get a couple of sparks sometimes before it breaks down, one might get by in a pinch but I would not be comfortable sport hunting or holding off hostile savages with obsidian unless it was on the tip of my arrows.

 

[Claude Mathis]

Obsidian is volcanic glass- I have never seen glass make sparks.

It's my understanding that the "flint" is scraping pieces of metal off the frizzen and that is what is "hot" (making the spark) not the rock itself. Is that not the case?

 

[Rod Lassey]

Might get ahold of Rich Pierce, who posts here now and again. Rich wrote a very informative article on the subject in On The Trail magazine an issue or two ago. Rich makes gunflints out of grey Missouri flint. If you just want to buy some, he's the man to talk to.

Rod

 

[paulvallandigham]

You are correct, Claude. :thumbsup:

 

[Coot]

The 'sparks' are indeed hot bits of the steel. The 'flint' must be hard enough to scrape off the bits of steel. Is glass hard enough? Is obsidian harder than (man-made) glass? Seems that a simple experiment with a fire steel (before going to the trouble of knaping into a gunflint) should verify if the material (glass, rock, whatever) will work as a gunflint.

 

[Runner]

If you get the gray semi-transluscent chert in solid enough pieces to make tools, it is pretty tough material. Rich, are you getting clean material big enough to do knife blades or lance tips? I am using petrified wood collected off gravel bars when the rivers are down. It does not knap well at all.

 

[tg]

I tried some peterfried wood a couple of times and ended up with peterfried sawdust, I could not get it to fracture like flint or obsidian.

 

[armymedic.2]

aha, exactly what i was hoping to hear. i do have a little chert, but not much. should be fun though. as i said the obsidian would probably be too brittle, thanks for telling me that notion was spot on. i didn't think the heat treat would matter, but you are correwct that it too would probably be too weak because that's what heat treating does. good point. ill give it a shot, and if works out ill try to put up a pic. thanks guys........knapping petrified wood? at least with slate you can grind it. try that on the wood!

 

[Runner]

I am a lapidary so I have saws and laps to form flints out of the stuff. No way to knap it at all.

 

[wulf]

I would be interested in learning the result of
your cutting a flint out of a piece of quartz.
I have used some and thought it sparked well but
never could get it shaped like a flint..I don't
have any of the equiptment to do the cutting so
I hope to find out from a person like yourself
who has the means...Quartz is readly available
here in Arizona....Wulf

 

[Runner]

I have not tried quartz, but the clear agate in the thunder eggs works just fine. As you go from the softest of this mineral group to the hardest, the edge that they break to gets less sharp. Obsidian breaks so sharp the shards will go right thru leather welding gloves with no problem. It will spark a few times until it is dulled or falls apart. The sharp edge gets sparks even tho the material is too soft. When you get to the harder agates and quartz, they still have the conchoidal fracture. They just don't form as sharp an edge as the softer materials like true flint. The balancing point is when you find a material that is hard/tough enough to last under the abuse a flint recieves, but still forms a sharp enough fracture edge to cause sparks reliably. Not only do they not form as sharp of an edge, but they also don't fracture back from the edge leaving another sharp edge for the next shot. The edge is destroyed and becomes dull. The very best material I have used so far was a high grade bloodstone scrap. It went around 30 shots in my Tradition's lock without a problem. In one of the nicer locks, it would have lasted a long time. You can refresh the edge on the cut agate flints and such using the flat diamond sharpening laps sold cheap at places like Harbor Freight. There is another thread here about using Mizzy wheels and Diamond grinding bits to correct the shapes on flints. The same things can be used to re-sharpen the cut flints or to put an edge on a piece of stone you want to try out. I have a piece of black flint here that throws sparks like you would not believe. Pretty material but it doesn't last in the cock on my gun. It works great for the fire start tho! I can pretty much cover the char with sparks in one strike! Pick up the local rocks looking for the stone that breaks to a sharp edge. Garnet works very well and it flakes back from the edge staying sharp. It doesn't take the abuse my Tradition's lock puts our well enough to be worth the extra cost!

 

[sniper68]

While in no way am I a lapidary, but I've designed and built a high speed, water cooled lapidary grinding system just for flints(trial and error method=$$ ) I just got some reddish Kentucky flint that I'm gonna try. I can't knapp so it's hard to get some chunks close enough shaped to resemble a flint. :cursing:. There is so much flint in this country, I surmise that some types would have to make as good of gun flints as the English and french do. :hmm: Initially I was just squaring up English and french, so the tops and bottoms are parallel to the knapped edge. Then I tried redoing the whole flint. Example, a wore out 1" I would completely reshape to a 3/4" or 5/8", grinding a new edge and all. With the proper ground edge, one or two dry fires will knapp the edge. Works perfect !!
I bought a bag of rejects and a couple dozen regular flints from Rich Pierce a while back. I straightened up the flats on the good ones and ground completely the rejects. I sent them to a dozen or so different shooters for testing. Seems to be as good or maybe even a little better than English. Definitely looks promising. A few have claimed 150 plus on Riche's flint. :shocked2:

 

[skunkskinner]

I would be interested in seeing a picture of your grinder system If you would like to share it.

 

[Runner]

You can buy a hobby flat lap machine that is good for this kind of work for about 200$ including the full set up. You can find better used machines for about 300 to 500$. Unless you have a shop where a machine can be set up, the self contained hobby machines are better. A 6 inch flat lap in a more aggressive grit than comes with them is all anyone would need extra, and then only if they are doing a lot of volume so time becomes a factor.
There are older units out there that have a polish head on the end of the shaft, a rubber drum sander station that is sheilded to use wet. Then there is the main grinding station that has two 10 inch silican carbide stones, and the end is a 10 inch wet diamond saw with clamp and pulleys for a weight to pull the clamp past the blade. These are as good as it gets unless you find an all diamond unit like it. They are big and take up lots of room. Mine is about 7 feet long. These units can be found cheap sometimes because they end up stuck in the corner in peoples way.
Technically, any grinder capable of running wet will work with a diamond or silicon carbide stone.

 

[TANSTAAFL]

It does. I have some local obsidian here and put a piece in the jaws of my flinter. It sparked but broke on the first try. It does spark though.

I should say you have some there. My winter neighbors from OR bring me down a tub of it every year. They said there is mountain of it where you can just go and pick up both the black and mahogany.