View Full Version : Cutting oil for Brass?
09-19-2001, 11:19 AM
I have a bunch of holes to tap in brass model pipe fittings and threads to cut on copper tubing for a modelmaking project. While I can do the tapping without lube, is there an appropriate fluid to spped the work?
grace & peace
09-20-2001, 04:57 AM
I am getting into this lard oil bit. Use bacon grease. My old machinery hand book says mineral oil, lard oil mix, 10% lard oil.
It also says soluable oil and water, 96% water.
I'd probably use bacon grease straight and see what happens, might mix in some hydralic oil, don't have any straight mineral oil sitting around.
Sulpherized cutting oils will stain brass, so don't use them.
One thing with brass: you want wicked sharp taps. I also found, when tapping a pipe thread in brass, that one of those interrupted-thread taps (the kind that look as though about half the teeth on the tap are missing) worked well.
I don't have a whole lot of experience with cutting fluids for brass. I'd probably try one of the things like Tap-Magic or Edge.
I've read that, for copper, milk is the answer, but I assume in the 60 years or so since that book was published something better has come along. Maybe not. I've never tried it....
09-20-2001, 10:59 AM
I've used bacon grease for drilling steel for quite a long time, but it's been quite a while since I had a shop set up and I eat a lot less bacon than I did in the past.
What I like about bacon grease is it melts as the drill gets hot, melting as necessary to keep the bit lubed and cool.
grace & peace
[This message has been edited by willjordan (edited 09-20-2001).]
09-21-2001, 02:20 AM
I too have heard of milk for copper - never tried it. I use A-9 on Copper and Aluminum. Valenite Valtap Blue is designed for ferrous and non-ferrous but can stain Aluminum. Tap Magic has lots of good stuff and eco-freindly fluids as well.
The best thing about bacon grease is the delicious way it is made - Mmmmmm...bacon!
Make that Canadian Back Bacon...numm!
[This message has been edited by Thrud (edited 09-21-2001).]
09-21-2001, 06:30 AM
I use a solid stick lubricant for tapping brass. This lubricant is a wax-like material in a 1/2" diameter stick and you just rub it on the tap. ENCO sells it as "Tap-Eaze" (made by AGS Co.). However, you can also buy the exact same stuff at an auto parts store; it's labeled "Door-Eaze" and comes in a 3/4" diameter stick. Made by the same company, just marketed differently. Hope this helps.
09-21-2001, 01:01 PM
[This message has been edited by pgmrdan (edited 03-19-2004).]
09-21-2001, 11:31 PM
I use Crisco in the little tin foil tub for ALL my tapping. Never had a problem with sticking, jamming, broken taps, hangover or nuclear fallout. It gets a little moldy and smells bad after spending the summer in the shop, also thins out in heat, but, like that stupid rabbit, it just keeps on going and going and going............