How'd They Do That?

Bill Skinner
Registered User
Bill Skinner
Registered User
Joined: May 1st, 2011, 3:00 am

July 4th, 2018, 4:31 pm #1

This is inspired by the thread about making copper.

In the southeastern US, during the late Woodland Period to the end of the Mississippian Era, the Native Americans practiced working copper down to thin sheets and then making ornaments and jewelry from them.  They did chasing and reppose with non ferrous tools.  And probably not by setting the metal in a bowl of pitch mixed with tallow and plaster while they did it.

I am working or more properly, fiddling, with copper, trying to make something that looks sort of similar.

Anyone got any ideas?

PS:  Putting the copper nugget on a rock and beating on it with another rock will only work so so.  It doesn't get the copper down to 1/2 mm (.02 inch)  or less like the NA's did.  Right now, I am having some success with a smooth rock and an ash stump as an anvil. I believe that sanding may have been involved.   And work hardened copper can be used to cut and punch holes in heat softened copper.  And I do know what "air reposse" is and I think that may have been used. 

 
Quote
Like
Share

Hummingbird Point
Registered User
Hummingbird Point
Registered User
Joined: October 28th, 2009, 4:36 pm

July 4th, 2018, 5:18 pm #2

I know about nothing on the subject, but would offer the possibility that the copper used was especially soft .   Gabriel Archer, one of the Jamestown settlers, in being given a piece of native copper by a local chief noted:  "The copper he had, as also many of his people, was very flexible.  I bowed a piece of the thickness of a shilling round my finger as if it had been lead."
Quote
Like
Share

Brian T
Registered User
Brian T
Registered User
Joined: April 24th, 2015, 12:27 am

July 5th, 2018, 2:28 am #3

Copper work hardens when you beat on it or bend it.  
Some expected shift in the molecular structure.
You can mess that up with heat and slow cool.
Maybe some unexpected alloy could stay flexible but not any of the copper that I have.

I used 1/4" copper rod to forge a crude crooked knife.  
I got 2 swings of the 32 oz hammer then had to re-heat.

Learning that my striking accuracy was poor and my torch wasn't hot, I had a blacksmith
forge an adze blade from 1.5" x 6" x 1/4" copper plate.

I can't imagine a paleo process to forge a sheet from native copper nodule.
Quote
Like
Share

Bill Skinner
Registered User
Bill Skinner
Registered User
Joined: May 1st, 2011, 3:00 am

July 6th, 2018, 10:05 pm #4

Well, they did it.  So it can be done.  I just like trying to figure out how.

EDIT:  This is a guess, so I may be wrong.   The copper in the sites that I know here in N America is mostly something like 99.9% pure copper.  A lot of the European stuff was actually an alloy, especially the metals used in coinage.  Tin was added to make the metal tougher and more wear resistant.
Quote
Like
Share

Forager
Registered User
Forager
Registered User
Joined: October 22nd, 2010, 11:42 pm

July 7th, 2018, 3:49 am #5

Bill, a Lenape friend whom I see annually (or less) at primitive skills/experimental archaeology events once set out to attempt to replicate thinned and rolled cylindrical copper beads made by his ancestors.  He got some copper from the Great Lakes and hammered it thin with a stone, burnished it and succeeded in rolling it into beads which very closely approximated those he'd referenced from the archaeological finds.  I considered his patient and persistent efforts successful.  

He encountered difficulties in his trials, as I recall there was a tendency toward cracking (which he resolved) and he was unable to achieve exceptional thinness (although he matched the ancient models which weren't remarkably thin).  My sense from his reflections was that the challenges pertained more to the purity of the specific (geologic) grade than the methods he employed.  I do not recall him using heat - just percussion and pressure, if my memory is accurate.

Good luck on your experiments, I'll be among those cheering you on from the sidelines.
Quote
Like
Share

Bill Skinner
Registered User
Bill Skinner
Registered User
Joined: May 1st, 2011, 3:00 am

July 7th, 2018, 5:03 pm #6

I can already do the Mississippian style rolled beads, working the smaller pieces down is time consuming but not difficult.  If it's cracking, just heat it up.  Those pieces are about the size of a stick of gum though.  I want to be able to make the larger pieces, about the size of your hand and larger, up to about plate sized.  I have hammered a chunk that started out about the size of the smallest joint of your little finger into a piece about a little larger than a 3 X 5 card.  It has lots of little tiny flats from the points and rough spots that are basically flattened mushrooms.  The top hammered out flat but the they  are still attached in the middle.  When I put a nugget on the ash stump, those small rough spots stuck int the wood and some of them came off.  I'm using a smooth quartzite hammer stone, BTW.  Other problem is the middle is still too thick, around .04 or a little less.  That's a little thinner than a penny.  This is thick enough to destroy the bone and antler tools I an using to make lines and impressions, though.  
Quote
Like
Share

spoons
Registered User
spoons
Registered User
Joined: January 28th, 2009, 1:49 am

September 15th, 2018, 1:57 am #7

try heating your copper hot then a rapid quench in water, copper works the opposite  of steel.
Quote
Like
Share

Bill Skinner
Registered User
Bill Skinner
Registered User
Joined: May 1st, 2011, 3:00 am

September 18th, 2018, 2:20 pm #8

Oh yes, heating and quenching is a given.  Sorry I didn't make that clearer.  You can let it air cool, it'll still be soft enough to work.

One of the papers written back in the late 40's mentioned partially hammered copper nuggets.  I have found that a work hardened copper punch will punch holes in the softer heated copper and a copper chisel with a work hardened bit will cut the same copper.  I'm thinking sanding with a soft, fine sandstone on a flat wood surface will both remove the high spot and the bumps.  I haven't tried it yet, it's been too hot to work outside on this.  The cooler mornings are reserved for real work, unfortunately.  
Quote
Like
Share

Brian T
Registered User
Brian T
Registered User
Joined: April 24th, 2015, 12:27 am

September 18th, 2018, 4:40 pm #9

I hammered a crooked knife blade out of 1/4" copper rod with a bottle torch.   Quenching in water.
In finishing, every river stone I tried got packed up with copper fines and rendered useless quite quickly.  
All I learned was that you might as well work at river's edge for all the stones you will need.
So I chalked up a couple of mill files and did a fast forward.

I had a blacksmith/farrier make adze blades for me from 1/4" copper bar.
No easier to finish the edge.

Must have been an autumn activity.  The smaller stoney mountain rivers run too high and hard in the summer with snow melt.
I would not dream of fishing around for stones in the fast, cold, murky current.
These days, it's snowing again up top and things are tightening up so the water levels in the mornings are quite low.
Quote
Like
Share

Bill Skinner
Registered User
Bill Skinner
Registered User
Joined: May 1st, 2011, 3:00 am

September 21st, 2018, 5:25 pm #10

I'm guessing it was probably a late Fall,Winter, early Spring event where I am, summer temps are way too high to want to be working next to a fire.  Oddly enough, one of the sites that a lot of people believe was a major site for working copper was in north Florida.  On the Gulf side, so no nice cool Atlantic breezes.
Quote
Like
Share

Brian T
Registered User
Brian T
Registered User
Joined: April 24th, 2015, 12:27 am

September 21st, 2018, 8:06 pm #11

I agree and copper was traded all over the continent, as well.  
I'm just at 53N and I have no appetite to work outdoors here in winter.
If copper nuggets in river gravels are washing out of mineral deposits, you'd never see anything
until low water in the autumn.  I have seen some of the copper nuggets.  Black with oxide and pea to walnut size.

Here in the Pac NW, copper was symbolic of prosperity and wealth.  Not used for tools.  Beaten into sheets.
That must have been some grunt of a stone-age job.

If this works, you see the two adze blades forged from 1/4" copper bar stock and dry-hafted as D adze.
My steel D adze is in the front.  The snail tells you how fast I work.  The pipe is the bobbin for the cord.
#18 tarred nylon seine line works well.



AdzesB.JPG CopperDAdzeB.JPG Kestrel 20s.jpg
Quote
Like
Share

Brian T
Registered User
Brian T
Registered User
Joined: April 24th, 2015, 12:27 am

September 22nd, 2018, 1:57 am #12

I still find posting pictures quite complicated.  What you see above are some of my everyday wood carving tools.

Adze blades cost me about $100 each so I don't have many.  One elbow adze blade on the bench right now to be hafted.
The adzes are rough out tools for basic shaping.  The two handed planer knives are for smoothing surfaces of split woods.
The whipping only covers all my dirty, sweaty hand grime!

They look stupidly simple in design.  Not quite.  

The planers are dog leg for left and right use.  Those blades were farrier's hoof knife blades in a past life.
The D-adze can be pushed like a plane.  Used for shallow texturing surfaces.  Maybe 1/32" chips on a good day.
One of my favorite tools to use.  The strikes make sense in my head.

The elbow adze is engineered.  The handle area is thinned to 7/8" and rounded.  
For me, this is the Kestrel Constant for handle thickness to fit my hands.  The D-adze is cut this way.
Palm up, fist grip.  The tips of your second and third fingers should just touch the fat ball part of your thumb.

See the yellow whipping?  The top break to the black is the Holm Constant = the best place to hold for striking all day.
No faster than your heart.  It, too, is 7/8" and rounded.  The location comes off the cutting edge at 90 degrees.
Of course you can choke up on the handle.  But for several hours of rough-out chopping, back down.
Quote
Like
Share

warmndry
Registered User
warmndry
Registered User
Joined: May 7th, 2018, 6:27 am

Yesterday, 2:23 pm #13

Sorry to arrive so late, but I wanted to mention the people who beat gold into gilding do it between leather pads. Admittedly gold is more ductile and softer than copper, but then again gold leaf can be beaten to 1 micron thickness and the copper does not need to be so thin.
Quote
Like
Share