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ZINOM
02-11-2008, 01:20 PM
Hey all,

I have some small parts cast in bronze from time to time, that then require machining (drilling and some milling).

Thing is, my foundry guy usually tries to sway me from casting in brass, but I find the bronze to be a bit slower going in the milling operations.

Due to the bronze containing a lot of copper, does the fact that the metal cools slowly (after casting) cause it to harden a bit.

I was pretty sure that slow cool for copper hardens while quench cooling softens it.

So I guess my question is: if my thinking is kinda correct, would I be able to stack the deck in my favor a bit by annealing the parts using my limited equipment (Mapp gas)

Also, if it IS possible, any technical guidance would be helpful, i.e. how hot to get it and for how long, what to quench in, etc.

The parts in question are similar to the iron frame part shown in these photos....around 4" tall

http://www.mpiretattoo.com/machinelinks/iron1007.htm


Thanks for you help in advance!

John

tattoomike68
02-11-2008, 01:41 PM
Its worth a try as long as you have no sharp edges that could stress and crack.

I made Tattoo machine frames from solid aluminum myself.

http://img.photobucket.com/albums/v488/miketattoo68/tattooframe.jpg

Those bronze frames would look nice with some engraving and nickel plated.

Tel
02-11-2008, 02:06 PM
Nope, a slow cool for copper will still soften it - all the quench will do is

a. Shock most of the crud off it
b. Let you handle it quicker.

Can't really help with annealing bronze - some machine better than others.

SGW
02-11-2008, 03:31 PM
Brass or bronze doesn't harden the way steel does -- as Tel says, whether you cool it quickly or slowly, the result is the same. Although there are a gazillion kinds of brass and bronze, in general bronze is more difficult to machine than brass, just because of the microstructure of the alloy.

ZINOM
02-11-2008, 05:30 PM
Thanks for the replies so far....I know I had seen several references (online) to annealing copper by heating and quenching....the opposite of steel. I figured the copper content of the bronze might allow some similar results....guess not eh?

Nice frame Mike....neat shape.


Additional opinions welcome.

John

gzig5
02-11-2008, 05:34 PM
Thanks for the replies so far....I know I had seen several references (online) to annealing copper by heating and quenching....the opposite of steel. I figured the copper content of the bronze might allow some similar results....guess not eh?

Nice frame Mike....neat shape.


Additional opinions welcome.

John

Not sure, but I don't think the quech operation is required to anneal it. I think that is done simply to be able to handle it sooner. I know that when I anneal brass cartridge cases, I am dunking them in water so the head area of the case doesn't get too hot.

SGW
02-11-2008, 06:55 PM
No, as far as I know quenching copper or brass just speeds up the operation. I don't think it has any particular effect on the hardness.

dicks42000
02-11-2008, 11:34 PM
OK, some of the guys have it right, non-ferrous alloys like brasses, bronzes etc. cannot be "hardened" by quenching & tempering. There is no carbon in the alloy and carbide (ferrite & cementite) precipitation isn't possible. They do work harden, as you know, hence annealing works to restore the crystalline structure to the original state. "Quenching" is only to cool the work piece for handling convenience.

However, some non-ferrous alloys, including Aluminum are hardened by "solution heat treatment", nitriding etc....

I generally find brasses to machine far easier than bronzes. I've had some pieces of bronze that seemed like they were alloy steel. Silicon bronze and Toban bronze have some marine applications for corrosion resistance and of course for bearings. Brass works OK for faucets & fittings (except red brass...too much lead) for potable water. Much easier to machine than copper. Don't use brass under salt water or in a corrosive environment. Electrolysis eats it away in no time. (Seems to corrode the zinc component first leaving a spongy structure....?

I would think that difficulties machining bronzes can be due to it's higher tensile strength (some alloys are very high) and its copper content. Raw copper is very "gummy" and builds up on HSS tools IME.

"Monel" is interesting to work with too, a family of copper-nickle alloys. Great corrosion resistance, strong, often used for marine tailshafts, chemical equipment and phenominally expensive.

Have fun;
Rick

CCWKen
02-11-2008, 11:35 PM
Man, those things must get pretty heavy after a while! :eek:
Brass is copper alloyed with zinc and Bronze is copper alloyed with tin. The bronzes are inherently harder than brass. Machining difficulty depends on the additions to the alloy. If it's a silicone or phosphor bronze, it will be more difficult to machine. Small additions of lead can help machinability. You might check with your foundry and see if a different bronze alloy can be used. Bronze is better because it has a higher corrosion resistance than brass. But... If you switched to brass, you could extend life by having them plated as mentioned.

You can anneal it before drilling or machining but I doubt you'll gain any workability as it's annealed when you get it. (Unless it's being forged or worked before you get it.) It generally won't work harden unless you roll or beat it.

tattoomike68
02-12-2008, 12:00 AM
Man, those things must get pretty heavy after a while! :eek:
.


The dual coil machines are heavy, I used a rotary liner machine when I worked in a tattoo shop and just used the coil machines for 4-12 nettle shaders running color.

this is a rotary..

http://www.pricksofthetrade.com/images/cart/tattoo-machines/rotary-tattoo-machine1.jpg

The newest thing is the pneumatic tattoo machine. Weight- 1.5 ounce About 1/5 the weight of the classic hot coil buzzer machine.

http://www.neumatattoomachines.com/images/catalog/products/blue2.jpg

There is good money in making Tattoo machines. they run from $170 - $350+ and they are easy to build.

dilligaf
02-12-2008, 08:41 AM
tattoomike do you have any plans and locations for buying the mototr and such i have alawys wante to build my own tattoo gun?

thanks
Dilligaf

ZINOM
02-12-2008, 09:34 AM
I hope you don't plan on tattooing yourself or others without proper training....?

John

dilligaf
02-12-2008, 11:47 AM
no but i would love to learn and the best way is to know the equipment so why not make a gun.

ZINOM
02-12-2008, 01:59 PM
It IS good to know the equipment, but you also don't want to put the cart before the horse.

I know many great tattooers, who operate in a socially and medically responsible manner....but they don't know much about the machines.....I would much rather THAT be the case, than someone who knows how to build a machine but doesn't know anything about cross-contamination and universal precautions.

The public's safety depends on responsible, professional tattooers operating in professional and responsible ways.

If you want to learn, your best bet would be to seek out an apprenticeship with an artist/studio....just try to make sure their practices are above board.

Good luck,

John

dilligaf
02-12-2008, 02:27 PM
i have now about 20 tottoos all from the same artist. I can go to him and use his equipment and his fake skin to pratice on. I have used his guns in the past to play with on fake skin. I know what it is to be medically renosanble. I would also like to build a gun to let him try and maybe use on me if he likes it. I would never give myself or anyone else a tatoo I cant even draw a stick figure. But i can build things and that is all that i am trying to do.

thanks
Dilligaf

tattoomike68
02-12-2008, 03:41 PM
It IS good to know the equipment, but you also don't want to put the cart before the horse.

I know many great tattooers, who operate in a socially and medically responsible manner....but they don't know much about the machines.....I would much rather THAT be the case, than someone who knows how to build a machine but doesn't know anything about cross-contamination and universal precautions.

The public's safety depends on responsible, professional tattooers operating in professional and responsible ways.

If you want to learn, your best bet would be to seek out an apprenticeship with an artist/studio....just try to make sure their practices are above board.

Good luck,

John

Amen... I did an apprenticeship where I was drawing (100+ pages) and cleaning all the equipment long before I started sticking anything on skin. (6+ months)

The scare of hepatitis or even HIV is very real so I shy away from encouraging people from self starting in the trade.

dilligaf, If you know an artist your best bet would to ask him if you can measure some machine frames, tubes, grips and the other parts and make a few for him and credit you with some killer ink. take some calipers and some graph paper and go to his shop and draw a print right there.(he wont let you take his stuff out of the shop im sure)

I dont have prints for a tattoo machine every one is made to specs of the user and is a peice of art all onto itself. And... the term is TATTOO MACHINE, its never called a GUN by an artist. Guns are made for shooting things. ;)