• January Turning Challenge: Thin-Stemmed Something! (click here for details)
  • Conversations are now Direct Messages (click here for details)
  • Congratulations to John Lucas for "Lost and Found" being selected as Turning of the Week for January 13, 2025 (click here for details)
  • Welcome new registering member. Your username must be your real First and Last name (for example: John Doe). "Screen names" and "handles" are not allowed and your registration will be deleted if you don't use your real name. Also, do not use all caps nor all lower case.

turning brass

Alan Carter

Alan Carter

Joined
Mar 23, 2009
Messages
37
Likes
4
Location
Lisle, IL
Website
www.alancarterstudio.com
I want to turn some brass rod to use as finial tops, design elements, etc. I've had some success using a file, but it's hard to get any really delicate looking shapes that way. I assume since brass is a lot softer than HHS tools, it can be done with regular tools running the lathe at slow speeds.

Does anyone have any tips or suggestions or "do not do this under any circumstances" thoughts?

Thanks.
 
Brass turns fine with sharp tools and dulls tools fairly fast. You can't take heavy cuts. There is no "grain" to brass so all the work is scraping even if the curls you can get off brass appear to be cuts. Natural brass will hold a LOT of detail. Sanding will wear out sandpaper very quickly. Silicon Carbide sandpaper last longer than Aluminum oxide paper does. Wet sanding is messy but can keep SiC paper from clogging up. You can sand to very high grits to good effect. A film finish like lacquer can help slow tarnish to years instead of months.

Aluminum is also a metal which can be turned if you want a silvery color.

You can of course turn many metals but you need harder tools and coolant to be effective.

Bone, like cow bone is another material which can be turned (stinks a bit) if you are looking for an "ivory" like finial.

Acrylics are easy to turn and you can apply several layers of gold leaf to acrylic for a "metal" look (the smoother the acrylic surface the better the gold leaf CAN look.
 
I turn a fair amount of brass. It turns well. I use shear cuts and get nice curls with a nice finish. You have to let the tool do the cutting which can seem like the tool moves much slower than with wood. You can scrape but when I want really fine details I still using a cutting action. If your getting chip out or a funny scraping kind of sound your feeding the tool too fast.
Brass can sometimes get really hard. If it's not cutting well anneal it. You do this by heating it until it's red hot and then quench it. This is the opposite of annealing steel. It will of course change it's color but as your turn and sand it will come back to the bright color.
Copper is the same as Brass. You can't change aluminum by heating but it sure turns well.
 
I haven't turned shapes, but I turn brass tool handle ferrules all the time from compression nuts. The brass turns nicely between 800-1200 r.p.m. on my mini. I use a tool with a small radius on the nose held at center height with zero rake.

Delta's 1954 book, "Getting the Most Out of Your Lathe" has more info on metal turning on a wood lathe.

Regards,

Matt
 
There are horror stories about using files as cutting tools, but I've had good results. I also turn ferrules from compression nuts. I grind down the top of the file to below the teeth for about 1 inch from the end, to reduce stress concentration (tension on top when used for cutting). Then I grind about 5-10 degrees relief angle at the end and the left-hand edge. Keep the tool rest as close as possible to the work.

For more complicated shapes, I'd use a HSS cutter in an Oland tool, with the end ground to suit the work. Again, use as little projection from the shank as possible, as well as projection from the tool rest.
 
Joe If you'll heat the file to 425 degrees you will reduce the brittleness to make it safer. I just throw them in the oven. I'm still not advocating using files but just about all the early articles on turning had a mention of using a file as a scraper. they can shatter and be very dangerous.
I wrote an article on making tools and included using files because I wanted to show a safer way to do it. I tested several after tempering using the 425 degree temperature and I could break them but they didn't shatter. It reduces the hardness but not so much it won't work for cutting wood and non ferrous metals.
HSS steel tools still work better because they are designed to work at high temperatures so if you overheat the tool while cutting the brass you won't damage it or alter the temper.
I find the best thing when cutting metal with wood cutting tools is to experiment with different angles. I try a cutting angle first. If that produces chips then I'll try scraping or a shear scrape. most of the time if cutting with a spindle gouge in the normal mode doesn't work I can shear scrape with the wings of the spindle gouge. This almost always gives a cleaner cut than just scraping which often causes chatter and then has to be sanded out. Try all the methods and find which one works for you. As always, you ask 12 turners how to do something and you'll get 13 results, all that work.
 
John, you did not mention the length of time to temper the steel which is important in getting the desired temper. I have not tried it, but just making a WAG, I suppose that somewhere in the neighborhood of 30 minutes would be about right.
 
I'm not an expert on hardening but I do read a lot and have hardened quite a few things. Heat treating properly is a real science. Most of what I do is simply to prolong the life of the edge of tools I build and it seems to work. A file will skate across them when I'm done.
I think a general rule is 30 minutes per quarter inch of thickness to properly anneal or harden but this is probably similar to the 1" per year of drying time which we all know is just a ballpark guess. I don't usually do that. I heat the metal until it's non magnetic. I leave it a little longer to for the heat to travel through that part of the tool. Then I quench, or if annealing just let it cool naturally.
To anneal the Brass I just heat it red hot and quench. On the sizes that I have turned this has worked perfectly. If it ever doesn't seem to work I'll probably try to heat it for a longer period of time. My friend who specializes in copper sculptures often gets them work hardened and has to anneal them frequently during the process. He basically uses the same thing. Just heat them red hot and let them cool.
 
You must log in or register to reply here.
Back
Top