Making Solid copper bopper for Flintknapping

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Making Solid copper bopper for Flintknapping

Folsomman
Registered User
Joined: 29 Jul 2013, 15:13

05 Oct 2014, 15:54 #1

Anyone do any smelting? I have a bucket full of copper that I would like to have metal down and made into some copper boppers for flintknapping. They are large piece that came out of a 6500 horse power electrical motor. PM me or just answer back.
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Knifesmith
Registered User
Joined: 25 Jan 2008, 21:09

05 Oct 2014, 23:26 #2

So, more casting than smelting?

What sizes/shapes are you looking for? If you're looking for small enough pieces, casting can be done pretty easily with a low tech/low cost setup.

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Eric Dobratz
Scarab Forge
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toxophileken
Registered User
Joined: 15 Jan 2006, 04:55

06 Oct 2014, 05:51 #3

I thought I posted about this same thing somewhere, but now I can't remember where…

I have a forge, and some scrap copper. I'd like to make some good sizer boppers and spallers at some point. Probably in the 1.5"-2" diameter on the small end, and maybe 4" or wider for the spallers. Length on boppers probably 4"-6" (though I thought I saw some solid tip boppers that had tips that were maybe 2" or so long), and length on spallers possibly 8" to 12" or so. On, they'd be cylinders.

Thanks for posting this Folsomman, and thanks in advance for the advice, Eric.

Ken
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Knifesmith
Registered User
Joined: 25 Jan 2008, 21:09

07 Oct 2014, 04:19 #4

I think for the smaller ones you'd be able to cast them in graphite pretty easily. The larger ones, you'd probably need to move to a crucible (with flux anti-O2 covering layer) and specific casting material. Green sand may be easiest, but you could probably do lost wax as well (though with something that large, you'd probably want to figure out a way to do wax reclamation).

One thing to consider is that foundries are actually pretty common. There was one a couple of miles from my house when I lived in Torrance. If you're not interested in doing the casting yourself, you can pretty easily (and inexpensively if you're trading in raw material) get casting done.

For things that are simple cylinders (or variants thereof), it's probably easier to just buy copper rod and work from there. It's expensive, but again, if you've got scrap copper to trade in, you'd probably end up doing better than you could cost wise when you consider the price of refractory materials and the fuel to melt the copper.

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Eric Dobratz
Scarab Forge
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Folsomman
Registered User
Joined: 29 Jul 2013, 15:13

07 Oct 2014, 17:35 #5

I don't have anything to cast with, so I was hope to find someone that would be will to do it for me, for a price of course. I have about 15 pounds of copper and only what about three different size of bopper and they could keep whatever they don’t use.

Knife thanks for the info.
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Knifesmith
Registered User
Joined: 25 Jan 2008, 21:09

07 Oct 2014, 22:45 #6

Here's a site with current scrap copper prices:

http://rockawayrecycling.com/scrap_news ... ap-copper/

Again, unless anyone here with significant casting capabilities comes forward, the most inexpensive way of getting this done may be to find a local foundry that's willing to do small pieces.

What kids of shapes and sizes are you looking to have made? (this info will certainly help people decide if they are willing/capable of helping with this project).

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Eric Dobratz
Scarab Forge
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Don Abbott
Registered User
Joined: 28 Nov 2007, 21:52

08 Oct 2014, 13:10 #7

A lot of guys just use copper plumbing caps filled with lead. I think most use a ball pien or something to make 'em rounder before they fill them.

Like this:



However, I was watching a friend of mine knap last weekend, and he has switched to using a simple copper elbow with a wood handle... no filler, just the elbow.


He had developed a technique for striking with the side of the elbow instead of with the front.

You could buy a lot of elbows and caps for what you'd get out of 15lb of scrap.
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toxophileken
Registered User
Joined: 15 Jan 2006, 04:55

08 Oct 2014, 21:50 #8

Thanks Eric and Don.

Don, I made my own boppers with lead filled caps (rounded them off by putting a box end wrench in a vice and whacking on the cap for awhile); but there are some things a solid bopper might be better for.

There are all sorts of techniques, and some guys like one tool or technique over another, while others can do the same thing with another tool or technique, and some can do various things just as well with various tools and methods…

Part of the fun of learning is trying new tools and methods and seeing what works best for ourselves, I guess.

Ken
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