Thread: Brass Durability

Brass & Bronze are often used as self lubricating bearings, so they can withstand quite high wear under the right variables.

I think it also depends on the application you are envisioning. For example will there be an impact risk? Brass will bruise and deform more easily than many other metals. Brass bolts are common but have a different shear strength than steel ones.

I have made brass risers to hold my handle bars, brass grips, and a brass kick start pedal, and foot pegs all for my motorbike and they all have held up well and have aged with a cool patina.

Brass headed mallets for use on wood tools last for ages, but not great for driving a nail.

Maybe you can post what exactly you are thinking to use it for?

Brass and bronze both have copper in them, but are different alloys with different strengths. I'd be wary of using brass except for lightly loaded parts.
Leaded bronze and gun metal are good for bearings.
Not sure about these being self-lubricating? They work well with hard materials though - lubricated.
Some of my motorbikes use bronze valve guides and seats, the better for heat dissipation. But, they're not as durable as cast iron or hardened steel.
Cast iron is easy to machine, but can be messy.

That's my amateur's summary.

Jordan

Johan, it is a matter of personal preference. Brass is a nice and easy material to work with. It also looks good, especially when polished and new. It feels solid due to its weight, and it will not rust. On the down side, it can get brittle with age.

Did you notice on the links you provided, the guy is making tools for the "Uhrmacherdrehmaschine", which translates as watchmaker's lathe. Such lathe has a drive motor comparable to a household sewing machine. The cutting forces are very small. A brass toolpost will do a fine job. It will wear quicker than a steel toolpost would, but on a watchmaker lathe most workpieces are brass anyway, and the "chips" from turning tiny steel shafts are quite delicate too. I also notice the tool machines used on your links are very small, I can see a Proxxon mill. Some 30 years ago I used to own a Japanese Toyo lathe and mill, these were also sold under the name Sakai, and incidentally are still available today under the name Proxxon..... The lathe was 7.5kg with the chuck and everything, easy to carry along single handed. On such small machines, turning a 20mm diameter steel workpiece is a very slow and tedious affair. I think this is the main reason the guy in your link likes to use brass. Also, brass needs no coolant or lubricant, it cuts beautyfully dry without any ugly fumes... you see, such small tool machines are often used in spare bedrooms, and it is definitely easier to get short brass chips or alumnium chips out of a carpet than long sharp steel strings (my first workshops were in spare bedrooms, that is how I know about these subtle considerations when choosing workpiece materials).


In short, there is absolutely no reason why you should not use brass and aluminium for many of your hobby projects. Given the small items, I do not think the cost is a factor at all. Durability will be reduced of course, as ally and brass are softer than steel. But yours is a hobby/home workshop. You are not going to use your lathe/mill 8h per day / 5 days a week. You will not even clock 1/10 the number of hours per year. I see absolutely no reason why a brass toolpost or a brass boring head should not outlast you. I can assure you there is a 1000 times more fun and satisfaction in using a brass boring head that you designed and made yourself, over anything that you could buy ready made. Chris

PS: to answer your last question, there is quite a step in difficulty from casting Aluminium to casting Brass: Brass has a much higher melting point.
PPS: you will find that if you can afford to use Bronze instead of Brass, you will be able to make much more durable tools. As long as you are looking at very small workpieces like those for a watchmaker lathe, the extra cost should not be too bad.

Brass and Bronze alloys have as much variability in their properties as different steels and iron. I really like the aesthetic of the materiel.

I'm a big fan of aluminium bronzes, they are little darker than most brass(more like gold), but can be hardened to ductile iron levels, and can be as strong as mild steel. $1 and $2 coins are aluminium bronze and they seem to fare pretty well.

I get my aluminium bronze from submersible pump impellers from the scrappy.