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jdh239
04-18-2010, 12:08 AM
A few questions. I am going to be making some flint and steel striker fire starters for
some scouts, kind of like this:

http://www.black-bear-haversack.com/product_info.php/products_id/3494

I tried with mild steel, but not much sparking there. I found that you need to use high carbon steel. Does high carbon steel come in 1/8-1/4 inch by 1/2" plate? Can I use an old leaf spring in an application like this? or any other ideas as to where I can scrounge up some high carbon steel?

I do not have a forge. I was hoping to just find something kind of flat that can be bent, cut, and welded.

Any considerations when welding it? I read some stuff about pre and post heating it, but that seemed to be speaking about 1" or thicker stuff.

Essentially, I plan on cutting an 8" and 4" piece, put a bend in the middle of the 8" piece, and weld the 4" piece onto one side.

Any input would be appreciated

A_DAB_will_do
04-18-2010, 08:14 AM
I checked the link you posted and the striker shown was made by hammering a section of coil spring flat, and then twisting the ends and wrapping them around to make a functional way to grasp the striker. All in all, a nice looking piece of work.

Sounds like you want something more functional, and less decorated. I can't quite picture what you're going to have when you finish, based on the procedure you described.

But regardless, you can weld that high carbon steel if you pre-heat it to about 450°F, weld rapidly, and then put in an oven and slowly cool to room temp. You could also try packing it in very dry sand to insulate it and slow cooling.

If the piece cools too quickly, the welds will crack; almost immediately.

You might also explore brazing the joints in the striker. Because this is a mechanical bond, with no melting of the base metal, you'll avoid some of the problems with welding high carbon steel.

I'd start in a junkyard and check some old truck leaf springs with a file or your piece of flint; until you find something that the file won't cut or that produces a nice spark.

Cutting high carbon steel can be tough, so you might want to consider using an oxy-acetylene torch to cut your spring down to size. An abrasive saw will also work and give cleaner cuts.

Good luck.

denrep
04-18-2010, 09:30 AM
It's not so much the steel's carbon content as its surface finish.
For example, a flint won't spark when scratched on a smooth forklift tine, yet will throw showers from lightly rusted low-carbon sheet.

I'm thinking about striker blocks based on pocket-sized ignition point files... that is, if you can still buy them. :laugh

Although it's not very rustic, a common torch lighter flint that is threaded onto a short screw for a handle, makes a great sparker.

Good Luck

jdh239
04-18-2010, 11:34 AM
Here are some pics to show what I am kind of planning. These are made from mild steel (below). I do have a plasma cutter, so I can cut the leaf spring with that hopefully.

What about welding high carbon steel to mild steel? If I can find a leaf spring, and use it for the striker portion, that is all I care about. I have enough of this other mild steel to make the handles.

4sfed
04-18-2010, 11:54 AM
It's not so much the steel's carbon content as its surface finish.


You'll still get more sparks from a piece of high-carbon steel . . . think of a spark test on a grinding wheel.

A rat tail file would make a couple strikers. Heat to bend and anneal the end to be welded, then while it's still hot, use a stainless filler to attach the low carbon handle . . . cool slowly.

Edit: Now I see the curved handle is low carbon . . . just heat and bend a rat tail file.

Oldiron2
04-18-2010, 01:03 PM
Long ago I was found that some old pushrods I had lying around worked well for this purpose; I have no idea which engine they came from, but know that others were no good, and the ones which were had high carbon content and weren't 'stainless' alloys either. They were long enough to hold easily when using, but didn't fit into a pocket well.
IIRC, they worked well with any sharp, tough rock including obsidian and well-opalized petrified wood.

denrep
04-18-2010, 01:23 PM
The jumbo fire starters are cool, but to be more practical shouldn't carried gear be light-weight, compact, and multi-functional. I'm thinking that a small trip of steel attached to some existing piece of gear would be more practical than an all-out fire starter.

Try scratching a common striker flint on a common piece of used steel; the results will surprise you. I have the pics somewhere but I don't feel like digging for ‘em right now - maybe later.

Good Luck

Sandy
04-18-2010, 01:57 PM
I'd guess the point is to make something representitive of an older period and yet still somewhat practicle. And yep, I'd also think small and light weight is a big issue too as well as a knarly surface to facilitate breaking off as many little chips as possible. Thinking about it I wonder just how many of the steels in ole Daniel Boones' day were really "high carbon" so to speak. Carbon from the forge 'n fire probably.

Those of old you were chipping off a piece of this "high carbon" steel with a piece of flint and under force and friction. Probably iffy at best and a true treasure when you actually got your hands on a good piece of steel. :).

In fact I don't think todays flints are even flint. They are specially formulated pieces of steel, "fire steel". Combinations of magic mix that generate tons of sparks when you scrub off the particles with just about anything hard and sharp. I'm not sure that the "flints" in a lighter or the "flints" in your torch lighter even have any flint in them. They are actually pieces of fire steel and a serrated wheel or rod abrades them off to get the sparks.

I think this going back to Daniels Boones day should be fun and a good lesson for the kids in getting by with materials at hand. Good luck. :) Survival skills with less than a Walmart close by.

Or maybe I should say "how man suvived before Cabellos". ;)

4sfed
04-18-2010, 11:12 PM
I'd guess the point is to make something representitive of an older period and yet still somewhat practicle. And yep, I'd also think small and light weight is a big issue too as well as a knarly surface to facilitate breaking off as many little chips as possible. Thinking about it I wonder just how many of the steels in ole Daniel Boones' day were really "high carbon" so to speak. Carbon from the forge 'n fire probably.

Those of old you were chipping off a piece of this "high carbon" steel with a piece of flint and under force and friction. Probably iffy at best and a true treasure when you actually got your hands on a good piece of steel. :).


Good steel has been available since the dark ages . . . just expensive . . . and the flintlock was well developed by
1700. Here are some links, followed by the relavent information . . . describing the characteristics of a good
steel and flint ignition system for a blackpowder firearm, which is just as applicable to flint and steel fire starters.

http://science.howstuffworks.com/flintlock2.htm
If you strike iron or steel with flint, the flint flakes off tiny particles of iron. The force of the blow and the friction it creates
actually ignites the iron, and it burns rapidly to form Fe3O4.

http://mamaflinter.tripod.com/id1.html
First and foremost is your frizzen. It must be HARD! Nothing will drive a shooter crazier than a soft frizzen.

http://members.aye.net/~bspen/flintlockfaq.html
What makes a good frizzen?
Other than proper geometry and proper strength of the frizzen spring, proper temper. The action of flint on the frizzen is
identical to that we use in starting fire with flint and steel, in that the flint shaves off tiny flakes of steel, heating them
to very high temperature in the process. A properly tempered frizzen will create hot, white sparks that seem to sizzle
and bounce before they die. A frizzen that is too soft will give sparks that are more red than white, and seem to have
no life to them, dying quickly. The quantity of sparks is also obviously different between the two, the well tempered one
giving off great showers of sparks, the soft one very few, or none.

snoeproe
04-18-2010, 11:21 PM
ESAB's Sureweld 716P SMAW rod sounds interesting.

Sureweld 716P contains a special lime coating which permits trouble-free welds on “difficult” steels such as high-carbon, alloy, high-sulfur, free-machining and cold-rolled steels. The soft arc drive produces a good back bead in the open root and the stable arc will permit optimal deposits in both vertical up and down positions. The bead profile is smooth and slag can be easily removed. Sureweld 716P is designed for pipe up to API 5LX65. High amperages with corresponding high deposition rates make it more economical than conventional types on heavy work.

76GMC1500
04-19-2010, 01:04 AM
Long ago I was found that some old pushrods I had lying around worked well for this purpose; I have no idea which engine they came from, but know that others were no good, and the ones which were had high carbon content and weren't 'stainless' alloys either. They were long enough to hold easily when using, but didn't fit into a pocket well.
IIRC, they worked well with any sharp, tough rock including obsidian and well-opalized petrified wood.

Those must be the old cast iron pushrods out of Pontiac and Cadillac engines of the 60's and 70's. Cast iron has a substantially higher carbon content than any steel alloy.

Oldiron2
04-19-2010, 01:04 AM
I'd guess the point is to make something representitive of an older period and yet still somewhat practicle. And yep, I'd also think small and light weight is a big issue too as well as a knarly surface to facilitate breaking off as many little chips as possible. Thinking about it I wonder just how many of the steels in ole Daniel Boones' day were really "high carbon" so to speak. Carbon from the forge 'n fire probably.

Those of old you were chipping off a piece of this "high carbon" steel with a piece of flint and under force and friction. Probably iffy at best and a true treasure when you actually got your hands on a good piece of steel. :).

In fact I don't think todays flints are even flint. They are specially formulated pieces of steel, "fire steel". Combinations of magic mix that generate tons of sparks when you scrub off the particles with just about anything hard and sharp. I'm not sure that the "flints" in a lighter or the "flints" in your torch lighter even have any flint in them. They are actually pieces of fire steel and a serrated wheel or rod abrades them off to get the sparks.

I think this going back to Daniels Boones day should be fun and a good lesson for the kids in getting by with materials at hand. Good luck. :) Survival skills with less than a Walmart close by.

Or maybe I should say "how man suvived before Cabellos". ;)

I agree that the PO's purpose is likely to do things the "Old Way"; it's even more fun to succeed in making fire by rubbing two sticks together (and also much harder). :drinkup:

The modern "Flint" used in strikers and cigarette lighters is a mix of rare earth metals and iron oxide to make it harder, named "Misch Metal" (sometimes written as one word) after the German term for mixed. Invented by the same chemist who found some of those rare earths like Thorium and Cerium which we (as welders) have never heard of or had a use for, right? :D :D :D

Oldiron2
04-19-2010, 01:11 AM
Those must be the old cast iron pushrods out of Pontiac and Cadillac engines of the 60's and 70's. Cast iron has a substantially higher carbon content than any steel alloy.
It is definitely steel, not cast iron. I still have one in a candy box in the garage, along with the 'flint' and some tinder materials, plus a fireboard, spindle and rawhide 'bowstring".