Brass rod threading?

[georgerkahn]

I bought some 3/8" diameter brass rod with which I plan to make an air-rifle carrier on my Kubota tractor. I got the brass, and have a 3/8-16 die; after I heat/bend the brass (so it won't turn in vice), I plan to thread it. Googling, there are too many answers vis what lubricant (some say none!) to use. My plans are to mount four threaded, bent lengths of the brass rod to an Artillian frame which will cradle my air rifle. Hence, my threading will need go through the frame -- probably about 3/4" overall -- quite a long amount of (for me) threading.
Suggestions from well-seasoned, experienced gunsmith/machinists?


Thanks ever so much!!!
geo

[Winger Ed.]

I've threaded a bunch of 1/8th" Brass.
All I ever did was use common tapping oil like what ya find at Home Depot.
To keep the die from clogging or a shaving rolling up under the threads in the die,
I back off and clear the chips with a air hose, or even a tooth brush about every 1/3-ish to 1/2 revolution.

That's the same way I do when tapping or threading Steel things.

The only problems I've seen was when people just thought it was like a running a nut
or screw and didn't stop to clear the chips or use any oil.

[15meter]

Mineral spirits is all a screw machine shop that was a customer of mine in a prior life used.

Let it drain from the chips, screened it and reused it.

And they bought brass by the semi load. They used to make gas grill regulators by the hundreds of thousands.

Chinese imports killed them off.

The plant is now a warehouse for one of the casinos here in Michigan.

[country gent]

Several things will help here and make it easier.
Cut a nice angle/chamfer around the end, this gives a nice lead in for the die to start and follow.
Anchor lube is one of the best but even black oil will work. In brass lard is good too.
Work slow break chips often.
If you have a split die you can open it up for a rough pass then close back to size to finish the thread
Make sure and start the die from the right side the side with the angled threads you can use the back side to clear closer to a shoulder but it isnt meant for heavy cuts.

Once you get a good start make a half turn back up to break the chips work in this manner 2-3 turns if you can blow the chips out here and relube. Keep the chips cleared recutting or a build up will pull the die off center, and make for a poor finish

With a split die opening it up will lighten the first pass and leave a small amount for a finish pass. You want a "test" piece so when you close it you can cut a thread to make sure its to size but not to small. This can cut a very nice precise thread.

[Scrounge]

I've threaded a bunch of 1/8th" Brass.
All I ever did was use common tapping oil like what ya find at Home Depot.
To keep the die from clogging or a shaving rolling up under the threads in the die,
I back off and clear the chips with a air hose, or even a tooth brush about every 1/3-ish to 1/2 revolution.

That's the same way I do when tapping or threading Steel things.

The only problems I've seen was when people just thought it was like a running a nut
or screw and didn't stop to clear the chips or use any oil.

That's about right. Reverse the tap or die, every quarter turn or so to clear the chips, and get a cleaner & neater finish on the threads. The teachers at the class I took a few years ago were very fond of Tap Magic, and since they were providing it, I was fond of it too. Folks I know use WD-40 for a lot of stuff, and particularly for aluminum. It's light machine oil and Stoddard Solvent.

I don't like blowing chips off, the toothbrush is much better, but sometimes you gotta use air. Make sure you and anyone around you that have eyes are wearing eye protection if you do. Can't use a magnet to get brass out of your eyes.

Bill

[405grain]

Just curious: why brass? If it's for esthetics then I understand. If not, why not use all thread? All thread is cheaper, easier to bend and work with, If it's not galvanized you can easily weld on it (or braze), and it's available at almost any hardware store.

[georgerkahn]

Just curious: why brass? If it's for esthetics then I understand. If not, why not use all thread? All thread is cheaper, easier to bend and work with, If it's not galvanized you can easily weld on it (or braze), and it's available at almost any hardware store.

Probably because I'm not too smart ;). It's that I keep tractor outdoors -- waaaay too tall and wide to get into either garage or storage shed, and my thought was the brass would 1/ not rust and 2/ actually be pleasing to the eye in looks. I had priced a length of all-thread and the cost was within pennies versus the two 12-inch pieces of brass I had purchased. Vis a pneumatic propelled instrument ON a tractor is "sketchy" -- please do not go off-topic here :) -- but whether one reckons said instrument is or is not a "firearm" governs legality as it is ver boten to have a firearm in or on any motorized conveyance in New York State. Two "plusses" for me include use 100% on my own land and, with, say, a plastic "toweling" rain/snow-coat above it in my devised carrier -- it will be out of sight. But, at hand for the occasional, but regularly seen, moving target(s).
geo

[Daver7]

Hope this isn't too much of a thread drift.
I made this several years ago. It makes threading smaller stuff on a lathe really easy.

[georgerkahn]

Hope this isn't too much of a thread drift.
I made this several years ago. It makes threading smaller stuff on a lathe really easy.

My "go-to" is kind of similar, 'cept I use my Rockwell drill press. With drill press UN-plugged, I chuck workpiece in it, with die secured in a drill press vice (the die is in die-holder). I use a plumber's wrench to turn chuck -- the 1/2" or so wide cloth on a handle -- to manually turn the chuck. This almost guarantees 100% in-line -- no cross threading, etc. with lots of leverage to make turning/threading easy. Plus, I sit on a stool (w/ bad leg it really helps!) with a foot on the drill press foot-feed pedal. This way I can turn chuck with right hand, and use my left to drip on lub and/or give sprits of air from compressor gun. Sadly, MY (metal) lathe is an old Unimat SL from the 1960s which is a great tool -- but, too small for an adaptation of your tool for this project.
geo

[405grain]

Wait! Not able to have a firearm in your farm tractor?! That's just communism. Hope your evil plan works.

[BLAHUT]

I was taught kerosene on aluminum; last time I threaded brass this what I used, worked good for one small job; break chips often...

[HWooldridge]

I work in a production machine shop; we process many tons of brass every year. Our machines use a combination lubricating and cutting oil (no sulfur) and we often get 500,000 parts from certain tool positions.

For a handful of parts, you can thread brass dry, just take your time and break the curl shaving every half turn or so. We will often run a new program without turning on the oil, so the operator can watch the entire cycle. Brass is pretty friendly to work with and you should get good results.

[Cap'n Morgan]

If your brass rods are made from a free cutting brass alloy (and they probably are), you don't really need to use cutting fluid.
Don't worry about breaking the shavings either, as they will come off looking like golden Bullseye powder ;-)

If you have access to a lathe, it would be much easier to thread the rods before doing any bending. Use the tailstock (without center) to keep the die holder perpendicular to the rod, rest the holder handle against the bedway and turn the chuck with one hand, while pushing the (unlocked) tailstock against the die holder with the other. It sounds more complicated than it is.