DIY deep drawing?

I'm thinking spinning is more period correct and deep drawing is a bit more modern a technique.

If you really want to draw, rather than sink them with a hammer, you'll need some pretty fancy dies. Drawing requires resistance against the sheet being drawn, so that the material shrinks and then stretches before it can wrinkle. The force of resistance must be set very carefully.

Somewhere on the Web there must be a good description of it.

Good luck with it.

Paul K. Dickman

Don't know about that, drawn percussion cap boxes with fitted lids date back to the early 1800s. Also had metal tinderboxes, same friction fit lid, long before that. Flyball presses did a lot with manual power. Don't know how old spinning is, the spinning lathe would have to have some pretty hefty bearings and a considerable continuous source of power, can't see that happening with a treadle lathe. In any case, see what archive.org has for old-timey books on the subject. Most will date to after power punch presses became popular, doesn't mean that some of the same die-making techniques couldn't be used on a cheapie HF hydraulic press for onesies.

And if you use copper sheet and not brass, that can be manually deep formed using a hammer, a form and considerable skill. Not my idea of fun, but there are artisans that do that stuff all the time.

Stan

Paul posted an EXCELLENT PFD on deep drawing. The only thing I can add is that drawing is MAGIC! You sometimes have to bury chicken guts by the light of a full moon. I've lost a lot of sleep over drawing dies!

Thanks for the link Paul. I can do this myself easily. I guess I don't need deep drawn, just drawn cups. Eric

Greetings Stan, I could hammer form the brass fairly fast for the cups I want. Brass is no big deal to hammer form. It does require annealing more often than copper but it does move pretty fast under the hammer and maple is plenty hard enough for the form. Like you I am sure drawn cups have been around for at least 150 years. I have seen antiques, well over

100 years old, that had drawn brass items on them. And when were the first drawn brass cartridge cases made? Eric

Thanks Ed. Paul Dickman posted a link to Bonny Doon Engineering that gave me all the info I needed. It turns out that I really only need drawn parts, not deep drawn. Not so many steps, maybe only one. So I guess I will spin a few and draw a few. Tomorrow I will be picking up a 1/2 hp Black and Decker 4200 RPM AC/DC motor that has 6 brushes and a 1 hp Century 1725 RPM motor that is, I think, a repulsion start motor. It also has brushes, adjustable ones, rotation wise. The adjustment is for timing most likely, to get the least amount of sparking depending on the load. I don't know how old the B&D motor is, it came off an old pipe threading machine. And who knows how long it has been since B&D made or supplied motors for pipe threading machines. The end bells are open so you can see into the motor. The Century may be as old as 1903 and it also has open end bells. So I don't know which motor I will be using. But since the B&D motor probably has plenty of power for the lathe, and the speed can be controlled with a rheostat, it looks like the likely candidate. If I do decide to use it I will need to search for a really old rheostat that can handle the load. Eric

When Second Son started his current job at a stamping plant, I handed him my copy of "The metalurgy of deep drawing and pressing" by J. Dudley Jevons. John Wiley and Sons 1940. He still hasn't finished reading it. (700 pages) It does have some interesting reading.

And lots of chickens?

Oh YES! LOTS of chickens! But, once a drawing die is done right, it's good for decades and decades. They don't really wear.

How hard to make the dies & draw brass boxes like these?

What are those for? Any market/$?

Shields for electronics, and to build test fixtures. There is a market, but it is small. I used them to build DC blocks & RF detectors for Microdyne.

They are good for RF work, when you use a brass tube for the center conductor. The DC blocks looked flat, out past 430 MHz on a HP network analyzer. What that means is that other than the tiny insertion loss, it did nothing to affect the signal.

Too bad, very easy to make especially from thin brass.

I've filed and scraped microwave circuit tuning stubs to flatten out their response on a network analyzer. It seemed really odd to be using such archaic methods to fix space-age problems. jsw

At least you didn't have to resort to a torch & hammer. :)

You haven't lived till you tune a UHF TV broadcast diplexers with a '50s Kay sweep generator. (Made out of six inch copper pipe, and weighing over a ton.:( )

There wasn't enough storage space to keep more than a token few museum pieces, and only one semi-retiree who used the facilities to build his cavity filters etc. It was fascinating to see what he could make from brass tubing, but fortunately I had state-of-the-art components to play with, some so new they had hand-written one-digit serial numbers and many of the 'specs' were speculations rather than specifications jsw

Ive got a few books on Forming...lets see..Volume 4 of Metals Handbook, and some others if anybody wants them. Ill probably never ever use them and Ive already read them.

If there is any interest..Ill sort through my shelves and see what I have.