Newyorkamera.com

February 6, 2010

Raising a Pair of Copper Beakers – Start to Trim

Filed under: Uncategorized — Tags: , , , — Sage @ 2:27 pm

I started this project for two reasons. first I need to be more consistent with my hammer work and I wanted to see how closely I could raise a matching pair of vessels. Secondly I need to make some samples of repousse wine cups that embody a new direction in my ideas about decoration on these cups.

One disk has been started the other has only the center point marked with a punch. The disk is hammered in a depression on a stump from the perimeter toward the center.  This stretches the metal. I started with 5″ disks, 126 mm with hopes of raising a 60-70 mm beaker.

3192StartW

This photo shows the first round finished, the second round started where the roundness is restored and the finished second  round.

stages1W

This is what it looked like after the third round which was struck with a ball peen hammer.  These three rounds were done without annealing but to continue I must now anneal.

3198thrdonfirstW

I lightly set the bases on the inside so that I would have a reference point from which to begin raising the sides.

3200BothfinishFirstW

I marked the bases at 50 mm and raised the bowls on my pipe stake held in a vise. The bowl on the left is raised  the one on the right is still bowl shaped. The hammering from now on is all on the outside of the vessel. Top and side views below.

3208setbasesW

3209fstRaiseon2W

I crimped the second bowl  to see if there was any advantage to a more angular raising.

3211crimpedW3214crimpedraiseW

After raising the difference was minimal, only about 5 mm difference between the pieces.

3215BothFrstRaiseW

I set the bases on a flat round stake  in my upstairs studio, the light is better there and I can set the stake at a higher position so that Ican see the reflections of my hammer strikes clearly as they are made.  I scratched a 50 mm circle on the base and  set the base by flattening the bottom and striking the sides as I worked my way around the base.  The first cup has been  nearly set in this photo, the next shot shows the flattened base before I struck the sides. 

3231SetBaseW

3232SetBaseW

This is the stake, I only use one small portion of the edge, striking only on that spot to keep the base round.

3233SetBaseStakeW

This is the second piece before any striking has been done.

3234SetBasebeforeW

This is the desk with all my projects, the vise and cups are on the far side under the lamp.

3236SetBaseDeskW

The cups went back downstairs where I began to raise them on the pipe in my vise.

3238raiseafterbase

This is the round completed  with the newly set bases before I annealed them.

3241raisedshpbaseW

Next,  I went for another round of raising trying to close the beaker a little faster, this photo shows how much I am trying to move the metal on my pipe stake in the vise.

3249secondRaiseW

The bases were set again and another round after annealing.

3251SetBasesW

Another anneal and round of raising, the vessels are very close  to matching measurements.

3254thirdraiseW

At this point the bases are near where I wanted them to be but the tops were still too wide and not tall enough.

3257bothThirdW

I planished the bases to about a 30 mm height  and raised the vessels closing them more the rest of the way.  The beaker on the left is ready to be annealed and the one on the right is almost finished for this round.
3460FourthraiseW

3462planshbaseW

At this point I planished a little higher and closed the tops some more.  Another shot of the two pieces in two stages, the one on the left is ahead of the one on the right.

3464HalfFifthraiseW

At this point I began to planish lightly after raising and before annealing,  I wanted to lower some of the hammer marks so that later planishing didn’t have to be so heavy. I made one more round to close the tops some more.

3481BothseventhPlanshW

Planishing the tops after the final closing round made the beakers more circular. They had been slight ovals before I planished them.

3483bothsevenTopsW

Yesterday was the first day of my Spring classes at FIT, I took the beakers to show Gennady  who said I’d done a good job of raising them.  I told him about planishing lightly after completing a round of raising before annealing. He said that, with copper, light planishing was okay in most circumstances because copper is a pure metal. It is not a good idea to do that with  sterling silver,  which is an alloy.  The sterling surface could get “stretch marks” and there was a danger of causing the metal to layer,  with sterling it is always better to work on soft metal.

I took this short video of me annealing one of the beakers before I trimmed them.  Annealing happens very quickly when you heat from the inside  with a big torch. I also marked that when the green flames turned orange the piece was annealed. I think the flames were telling me the oxidation was finished and the metal had relaxed. You’ll hear the quench near the end of the video.

The beakers had already been marked with my surface gauge to a height of 65 mm which is where I trimmed them.

3489trimmed

No Comments »

No comments yet.

RSS feed for comments on this post. TrackBack URL

Leave a comment

You must be logged in to post a comment.

Powered by WordPress