Forming bag

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Forming bag

Postby googe » Sat Jan 12, 2013 6:37 pm

Hey all, this is more generalized to empty cause he's a copper smith, didnt realize that till i read it the other day ^:)^ . I thought i would put it here istead of pm him as other people cn see. I want to know what filling, bag material, size, shape is best for sheet forming. Thanks.


Re: Forming bag

Postby emptyglass » Sat Jan 12, 2013 8:32 pm

after reading your post a few times, i think i know what you are asking.
size of the job will determine size of the bag,
the ammount of curve you want will determine if you use sand, lead or something else.
Usually leather.

Re: Forming bag

Postby JayD » Sat Jan 12, 2013 8:46 pm

search youtube Googe you will find information there on metal forming.
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Re: Forming bag

Postby googe » Sat Jan 12, 2013 9:24 pm

Thanks empty, i want to do some bowl shaping, eg: a bowl 6' high by 6' diameter, what bag would suit doing that sort of stuff. Thanks Jayd, had a look around but wanted it striaght from the horses mouth, not that anyone is a horse here.

Re: Forming bag

Postby emptyglass » Sat Jan 12, 2013 10:50 pm

You'd possibly do better with a turned hardwood "bowl".
Get a bit of red gum or jarrah, turn a recess in it 6" wide and 3" deep, and form the copper in that. You will need a curved wooden mallet. You will have to form it in 2 halfs, then join it, so make sure one half has enough material to make a "lap" seam, that is, leave a bit extra on one half so you can overlap it on the other half.

Once you have your two halfs roughly formed, finnish them on a 6" "mushroom". This is best made from metal, but a wood one will do for a single or double use. I'm sure you can imagine a mushroom shape (leave a bit of a shank on it so you can hold it in a vice). This will give you that classic hammered finnish.

You may find you have to anneal the copper periodicly through the process. Cut your holes once you have the halfs formed, till you get a feel, then you can cut your holes in the flat sheet before you start.

And good on ya for asking the question publicly. I hate answering stuff like this in pm's where only one member can benifit.

The forming bag is a good place to start, but it helps to have the above mentioned stuff. A tradie can do this in a bag alone, but it takes some practice. Just start tin bashing, and you'll get there mate.

Re: Forming bag

Postby googe » Mon Jan 14, 2013 4:07 pm

Thanks mate, god that brings back memories of metal work at school talking about metal mushrooms and the rest!. I know what tools you mean. I map pretty good at metal work at school, loved it!. Just want to try some stuff with copper, instead of just soldering and crap. Not sure how I'd go getting a bowl and mushroom made, might have to ring some wood turning joints. When you mention do it in halves, is that because of kinking?. Thanks heaps mate :handgestures-thumbupleft:

Re: Forming bag

Postby emptyglass » Mon Jan 14, 2013 9:30 pm

googe wrote: When you mention do it in halves, is that because of kinking?. Thanks heaps mate :handgestures-thumbupleft:

Well, you cant make it one piece. 2 halfs is next best.
It not because of kinking. As you hammer it out, you will get kinks starting to form, don't let them get big, use the hammer to chase them out. This is real important if you are only using a bag, if you have a mold, you can bash it to shape. Metal will only strech, it wont compress (naturaly). Start with 1.2mm thick metal and your ball will be thinner once formed.
Using that mushroom thing is only decorative. Gives you that alembic still look. Some don't like that look.
Ever make a soup ladel at school?

They can also be metal spun, but thats a bit past the scope of what we are talking about.

Re: Forming bag

Postby googe » Fri Jan 18, 2013 11:25 pm

Thanks mate, very greatfull. Yeah i think a mushroom might be to much $ atm, will see what i can come up with regards to the bag. I didnt make a ladel, made this fruit bowl type thing, it was done on a small metal mushroom or half mushroom?, long time ago!!!. Thanks again mate.

Re: Forming bag

Postby crow » Sat Jan 19, 2013 7:02 pm

haaa yeah we did all that shit and had to solder.... :wtf: wait a second I soldered that poxed out pencil case at school Oh man going back out the shed for another go at this shit be back later
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Forming bag

Postby Sam. » Sat Jan 19, 2013 7:45 pm

Shouldn't solder anything on mushrooms.....
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Forming bag

Postby Rumdrinker » Sat Jan 19, 2013 9:13 pm

sam_and_liv wrote:Shouldn't solder anything on mushrooms.....

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