professional looking and repeatable sheet metal parts

[Chris Stein]

I need to incorporate a brass surround of between .010" and .060" thickness in a manufactured product (see picture attached).

It needs to be of professional appearance (meaning sharp, clean edges) and reproducible in large numbers at low cost.

What is the best way to proceed? None of the manual techniques I have at my disposal produce parts of sufficient uniformity or are fast enough for a production process.

Are there any stamping presses and die systems suitable for cottage industry? Any other suggestions?

Thanks,

Chris Stein

[Ralph_Monroe_Mi]

Chris,
I'm not sure I fully understand your drawing. I believe you want to cut a 7.25x 4.75 piece from an 8x 5.5 with radiused ends. This will be attached to your product.

A stamping press would not be a real ptoblem. There are a lot of excess small presses available cheap, depending on your locality. OBI (open back inclinable) presses are ideal for parts like this. Search OBI at HGR for a sampling. http://www.hgrindustrialsurplus.com/

Tooling is a more costly and would need to be farmed out unless you are an accomplished machinist and are able to absorb tool design quickly. The toughest part of your piece is going to be adequately holding the 3/8" web while you shear both side of it. Again small OBI sized diesets are available cheap. Finding one still has good guideposts and bushings is the biggest concern. Once hard tooling is built it is expensive to change

Another process used for small parts is pressing into urethane forms. I've never used it. It's proponents praise it. http://www.bonnydoonengineering.com/index.html

A third process would be to find a cnc laser or plasma service in your area. Many fab shops have open time on their machines. Programming is minimal cost, changes are easy. This may be the best way to go.

Volume is going to be a determinant.

[Chris Stein]

Thanks Ralph. Lots of good information.

And yes, you're correct, the center of the piece has been cut out. It's a narrow brass border.

There are a number of sheet metal shops with laser cutting capabilities in the immediate area. Perhaps I should price the job out with one or more of them before looking any further into purchasing the technology.

And as for quantity, initially very low, but if the product is a hit, hopefully we'll need 'em a hundred at a time.

Regards,

Chris

[Ralph_Monroe_Mi]

There are a number of sheet metal shops with laser cutting capabilities in the immediate area. Perhaps I should price the job out with one or more of them before looking any further into purchasing the technology.
Chris

Chris,
IMHO CNC laser is the way to go for medium volume flat work (up to about 40,000 annual). Beyond that a second laser may even be the way to go. Flexibility is the reason. New parts require a new locating fixture and a new program. Added holes or location changes only require a change to the program.

BTW when you get quotes from the S/M shops inquire whether or not they've included a scrap credit for your drops. That's a healthy sized piece of brass you'll be tossing.

[steve hermann]

having been a tin knocker for a lot of years and running a ingersol water cutter for about 8 years i would go with the waterjet cutting, slower but a cleaner edge and a lot less clean up. buy good brass and have the plastic left on when it is cut.

[steamin10]

My thoughts: business is. Try the market with waterjet samples, see if there is acceptance, adapt to preference. Keep your motive for profit sharp.
.
Make investment choices early, payback is part of the playback.
.
An obi or other press/shear is equipment that can be sold or traded if the deal flops, time bought on someone elses machine buys him a summer home. Dies are like an anchor, and a black hole for money, once its bought it is no good for other use. Dies that are damaged usually cannot be save or rebuilt, only replaced to maintain a quality window. In punching, wear will destroy the clearance, and give rollovers and fingernails, and pull/stretch marks. If material wedges between, it can fatigue and explode your die. So can worn guide posts, crashing dies faces together. A lot of techy stuff goes into running a good part, no matter what the machine. Punching (pressing) within machine capacity can be the dead-nuts cheapest way to produce simple parts.
.
Are you doing to do all the work your self? Are you buying a job? Or are you going to hire someone else or farm it all out. Cottage industry implies limited run and low tech, limited outside help (labor). If any operations take some knowledge or training for quality, it becomes problematic to keep your (skilled, trained) help.

[zakq]

Dear Chris; what is left of the costume jewelry trade in Providence, R.I. might be able to help. Much of the jewelry and gift ware was made from stampings. These parts were sold freely by stamping houses to the trade, ie. anyone who can pay. The general name for jewelry parts is findings. You may find a similar frame available in one of these firms. Much of the tooling is unit tooling; meaning one operation in a press. This allows them to mix and match different combinations of shapes and piercings to suit a costomers needs. If you are flexible on the actual size and shape of the frame you might find something suitable. Look in the R.I. phone book under jewelry findings and stampings. As the industry contracted the tooling of each firm that went out of business was bought up by the strong ones. Call up Sage and Salvadore stampings. After you describe the part, if they have nothing for you, ask if they know anyone else who might make something like your part. They will tell you. This is how the trade worked for generations. I used to work and live there for 20 odd years. Also you can have your part photo-etched to match your drawing. The price goes by the sheet. The photo tooling is cheap. The more parts on a sheet, the cheaper the piece price. They etch brass and silver.You can order the parts etched from a pre-polished sheet of brass. Also located in R.I. This another option for you. I don't know if it is cheaper than plasma or laser, but if you want a polished piece you are best working with a firm that is used to handling metal with a finish. Nothing worse than getting your parts made to size with deep scratches in them where you don't want them. Hope I helped. Best of luck.