The Steampunk Forum at Brass Goggles
October 21, 2017, 01:23:35 pm *
Welcome, Guest. Please login or register.
Did you miss your activation email?

Login with username, password and session length
News: Brassgoggles.co.uk - The Lighter Side Of Steampunk, follow @brasstech for forum technical problems & updates.
 
   Home   Blog Help Rules Login Register  
Pages: [1]   Go Down
  Print  
Author Topic: Sheetmetal technique?  (Read 1767 times)
jringling
Time Traveler
****
United States United States


convicted Rogue and Vagabond…long story…


WWW
« on: March 22, 2013, 12:31:11 am »

A quick question for metal workers...

I am trying to make a piece of sheetmetal jewelery that consists of 2 or 3 separate pieces that will overlap. I would like to flatten the metal layers so the overall thickness is uniform. I do not have a roller mill or a press, so I am thinking of hammering them... My question is should I place the pieces between blocks of wood? pieces of thick leather? Or will hammering not work and I need to use a vise as a press?

Any advise is appreciated...

-Jerry
Logged

HR
Zeppelin Captain
*****
United Kingdom United Kingdom


If at first you dont succeed, hit it with a hammer


« Reply #1 on: March 22, 2013, 12:53:58 am »

The wood or leather will absorb most of the force generated by the hammer blow and it will have little effect. I presume you don't want hammer marks on the finished piece. It is unlikely that a vice will exert enough pressure, so if you have access to a press I would go with that. The alternative is to use the hammer and then Polish out the marks. or you could but it between two pieces of steel (or an anvil and one piece) and hit that, but it will still leave marks that will have to be polished out.
« Last Edit: March 22, 2013, 12:58:59 am by HR » Logged
Dr cornelius quack
Rogue Ætherlord
*
United Kingdom United Kingdom


Arrant Carney. Phmebian Cultural Attache.


« Reply #2 on: March 22, 2013, 12:58:52 am »

How about using your knowledge of etching to produce a series of overlapping sections that have interlocking parts reduced to half thickness so as to remove the need for beating out multiple layers of full depth metal?
Logged

Such are the feeble bases on which many a public character rests.

Today, I am two, separate Gorillas.
jringling
Time Traveler
****
United States United States


convicted Rogue and Vagabond…long story…


WWW
« Reply #3 on: March 22, 2013, 01:09:27 am »

or you could but it between two pieces of steel (or an anvil and one piece) and hit that, but it will still leave marks that will have to be polished out.

I had this thought as well... Maybe I'll hunt down a smooth piece to use with my anvil...

How about using your knowledge of etching to produce a series of overlapping sections that have interlocking parts reduced to half thickness so as to remove the need for beating out multiple layers of full depth metal?

This is a thought but I want the folded / woven look...
Logged
Dr cornelius quack
Rogue Ætherlord
*
United Kingdom United Kingdom


Arrant Carney. Phmebian Cultural Attache.


« Reply #4 on: March 22, 2013, 01:15:28 am »

So etch out the parts that overlap and weave together afterwards.
Logged
jcbanner
Officer
***
United States United States



« Reply #5 on: March 22, 2013, 08:20:31 am »

what I would do would be to accentuate the overlap, with a crease on the top plate over where the bottom one ends. so the pieces would have a shape like _____   -----___   -----____

That not being the case though, and assuming that only one side will be visible and the other side needs to be unmarred, what I would do would be to place the pieces on a hard surface, such as the anvil plate on the back end of my bench vise and a thin piece of leather on top of them as I hammer them flat. the thin leather piece will prevent deep hammer marks which are a pain to get out but not absorb so much force that nothing gets through.  if the metal is sandwiched between softer materials before being struck, you'll only deform the softer materials. you could also use a jeweler's mallet, which should have a brass, hard rubber, hardwood, and acrylic resin striking surface.  if you're more concerned with speed of shaping then the cleanup, just just a lightweight ball-peen hammer. 
Logged
Narsil
Immortal
**
United Kingdom United Kingdom



WWW
« Reply #6 on: March 22, 2013, 10:37:35 am »


My understanding of your question is that you want to produce a step in the edge of each sheet, so that if the base metal is say 2mm thick it will be 1mm thick at a certain distance form the edge.

The problem with hammering or pressing the metal is that the metal has to go somewhere so you will end up expanding the edge that you thin which will tend to distort the whole sheet.

'Joggling' the edge is much more achievable. In this case you don't actually thin the metal but create an offset lip



In this case you will need to make a tool to form the edge over, you won't be able to do it just by hammering on a flat surface.

The best way to avoid hammer marks is to make sure that both the hammer or other striking tool and the striking surface are polished and have slightly crowned edges and make sure that you strike square-on. Using any kind of padding won't really help, you can use a soft backing, this needs to be something which will give a bit to allow the metal to move but won't spring back, lead is good for this. You also want to use lots of fast light blows rather than heavy ones. Soft face tools can be useful for gentle forming but you will need something harder to achieve anything like a sharp crease.

To do this without specialist tools probably the best technique is to first use something like a rounded edge chisel to form the step and then flatten the outside edge down.
Logged







A man of eighty has outlived probably three new schools of painting, two of architecture and poetry and a hundred in dress.
Lord Byron
jringling
Time Traveler
****
United States United States


convicted Rogue and Vagabond…long story…


WWW
« Reply #7 on: March 22, 2013, 10:46:16 pm »

I am looking for more of a basket weave look like these:

Spoiler (click to show/hide)

Spoiler (click to show/hide)

The metal sheet pieces will be half-hard 20ga, about 1/4"wide
Logged
RJBowman
Zeppelin Captain
*****


« Reply #8 on: March 23, 2013, 01:02:52 am »

Be aware that this suggestion could endanger you, and may possibly be illegal...

...Is the piece you're putting together narrower that a railroad rail?
Logged
jringling
Time Traveler
****
United States United States


convicted Rogue and Vagabond…long story…


WWW
« Reply #9 on: March 23, 2013, 01:29:05 am »

Yes, but the closest active rail is an hour and a half away... and I will have invested too much time in the pieces to risk the loss by train... I've lost many pennies that way, never to be found again...
Logged
Wilhelm Smydle
Snr. Officer
****
United States United States


« Reply #10 on: March 23, 2013, 02:40:44 am »

Could you anneal the metal and weld or rivet  the components together before applying brute force?
Working hot may also help depending in the material properties.

Hard solder may be an option.
Logged
Dr cornelius quack
Rogue Ætherlord
*
United Kingdom United Kingdom


Arrant Carney. Phmebian Cultural Attache.


« Reply #11 on: March 23, 2013, 08:13:20 am »

Put the piece between two sheets of hard rubber and park a car on it for a little while.

Hydraulic Car Jack?

Laundry Mangle/

http://en.wikipedia.org/wiki/Mangle_(machine)
Logged
Astalo
Zeppelin Captain
*****
Finland Finland



WWW
« Reply #12 on: March 23, 2013, 11:48:22 pm »

Rolling mill is probably much better for that, because laundry mangle can handle only soft materials. http://commons.wikimedia.org/wiki/File:Rolling-mill.jpg
Logged
Dr cornelius quack
Rogue Ætherlord
*
United Kingdom United Kingdom


Arrant Carney. Phmebian Cultural Attache.


« Reply #13 on: March 24, 2013, 12:43:15 am »

Rolling mill is probably much better for that, because laundry mangle can handle only soft materials.

You've never seen my laundry.
« Last Edit: March 24, 2013, 12:46:42 am by Dr cornelius quack » Logged
jringling
Time Traveler
****
United States United States


convicted Rogue and Vagabond…long story…


WWW
« Reply #14 on: March 25, 2013, 03:09:18 am »

Here is a test piece:
Spoiler (click to show/hide)

This was more of a practice for my new jeweler's saw than metal bending, but it gave me some ideas for forming sheet... I ended up just pressing it in the vise.

Lessons learned:

1. The jeweler's saw is a tough little bugger to operate. I think it takes more patience than I have, but I will continue to practice...

2. I need to build a hydraulic press. Alittle steel, afew bolts, and a bottle jack...
Logged
Wilhelm Smydle
Snr. Officer
****
United States United States


« Reply #15 on: March 26, 2013, 12:19:41 am »

Looks good, as for developing skill with a jewlers saw pratice, posture and lighting help a lot.
For thin material a sacraficial piece of hard board or paneling can help support the work.

Jewlers saws are useful and cut plastics, metal, wood, and skeletal materials.
I think mann's book also discusses culinary use of the tool.
Logged
Dr cornelius quack
Rogue Ætherlord
*
United Kingdom United Kingdom


Arrant Carney. Phmebian Cultural Attache.


« Reply #16 on: March 26, 2013, 01:48:25 am »

When the pieces are interlocked, how about using a rounded off tool (Small cold chisel or flat blade screwdriver) to crease across the strip at the line between the two pieces.
The beaten Copperware folks call it a 'Chaser', I believe.

http://en.wikipedia.org/wiki/Repouss%C3%A9_and_chasing
« Last Edit: March 26, 2013, 01:55:25 am by Dr cornelius quack » Logged
Daedalus Forge
Gunner
**
Wales Wales


I tolerate this century, but I don't enjoy it.

DaedalusForge
« Reply #17 on: March 31, 2013, 11:56:50 pm »

Dependent upon how thick, and, indeed, what type of metal you're using, you could try the forging technique of 'Drawing Down', whereby the metal is heated to the point where it's sufficiently malleable to forge (with sheet metal, you could achieve this with a blow-torch), and then hammered thinner.  As has been pointed out already, though, the material has to go somewhere; so it's not so much thinning as spreading.  Once sufficiently thinned, however, the piece could be re-cut to shape.  I suggest this technique because hot metal is far easier to work than cold metal - it can be done, but requires far more specialized equipment than a blow-torch, hammer, and anvil (suitably hard, flat surface).  Just a thought.
Logged

"The entire British Empire was built on cups of tea... and if you think I'm going to war without one, mate, you're mistaken."  Capt. Daedalus Dashwood Forge, immediately prior to the Battle of the Weddell Sea, Antarctica.
oldskoolpunk
Zeppelin Captain
*****
United States United States


WWW
« Reply #18 on: April 10, 2013, 04:00:41 am »

The wood or leather will absorb most of the force generated by the hammer blow and it will have little effect.
Hammering through something thin and tough, like inner tube scrap, might work. Try that on some scrap.
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.20 | SMF © 2013, Simple Machines Valid XHTML 1.0! Valid CSS!
Page created in 0.174 seconds with 17 queries.