Cast Bullet loaders? Babbit bearings for casting

millwright

CGN Ultra frequent flyer
Rating - 100%
483   0   0
Howdy All. Can an industrial babbit bearing or whats left of one be used for casting? I have access to used bearings that I could use if they are worth it.Thanks
 
A great deal of variation in babbit metal. Low speed, low pressure bearings were mostly lead, not sure what they were hardened with, but would be ideal for average bullets.
Bearings for high speed, high pressure use, such as bearings on planers used in sawmills, had a very hard, lead based metal. Some had nickel in them. Some old time machinests bought rolls of nickels to add to the molten metal, to help harden it up for extra tough use. Probably about ¼ high speed babbit to lead ratio, would make excellent bullets.
 
Babbit metals are mainly tin (Sn) alloyed with Antimony, Copper, and traces of lead. An example would be 90% tin, 5% Antimony, 4.8% Copper, and 0.2% lead. Babbit metal is soft and easily damaged, but has excellent "sliding" qualities. I have re-cast Babbit bearings in old machinery, and it is a nice material to work with in that context, especially when you have to "scrape in" the bearings for a good running fit.

I think the issue you might run into with casting bullets is the Brinnell Hardness Number, or BHN, of this material when cast. I'm not at all knowledgeable about alloying bullet metal, but I know that ideally cast bullets are best made from a metal alloy that falls in a certain range of BHN.

The Los Angeles Silhouette Club has a very good page on bullet casting metal alloys and their relative BHN's - you might want to start there.

ht tp://www.lasc.us/CastBulletNotes.htm
 
Last edited:
Mr. Beaver, I can see you never helped pour babbit for various bearings on old sawmill equipment!
I have some five pound ingots of babbit metal, unused, from Harris Metal of Canada. They are now collectors items and in 1995 I wrote to Harris Metal to see what their content was.
Here is a copy of the letter I received from them.
Note that they refer to it as "heavy Pressure babbit," meaning it is for heavy preasure and/or high speed. Babbit metal for slower turning, and lighter duty bearings, is mostly lead, as I pointed out.


File0002.jpg
 
Mr. Beaver, I have an apology, in that I had not thoroughly read your post, and missed the part where you had poured bearings.
However, I stand by my analysis of it.
 
Thanks guys for your input.I took the easy way and asked here first before doing any of my own research,why always duplicate when one can ask others who have been there before.
 
Mr. Beaver, I can see you never helped pour babbit for various bearings on old sawmill equipment!
I have some five pound ingots of babbit metal, unused, from Harris Metal of Canada. They are now collectors items and in 1995 I wrote to Harris Metal to see what their content was.
Here is a copy of the letter I received from them.
Note that they refer to it as "heavy Pressure babbit," meaning it is for heavy preasure and/or high speed. Babbit metal for slower turning, and lighter duty bearings, is mostly lead, as I pointed out.


File0002.jpg

I believe we are both correct for our respective experiences, as far as Babbitt metal composition is concerned.

"Babbitt metal, also called white metal, is an alloy used to provide the bearing surface in a plain bearing. It was invented in 1839 by Isaac Babbitt[1] in Taunton, Massachusetts, USA. The term is used today to describe a series of alloys used as a bearing metal. Babbit metal is characterized by its resistance to galling.

Common compositions for Babbitt alloys:

* 90% tin 10% copper
* 89% tin 7% antimony 4% copper
* 80% lead 15% antimony 5% tin"

In fact, I found both types of compositions for sale at various bearing metal suppliers after a quick google search.

And yes, I have not poured Babbitt bearings on old sawmill equipment. An old bandsaw, an old 7 1/2" table saw, and a small reduction pulley system are the limit of my experience. I defer to your broader knowledge of the subject :D
 
Yes you can use it. You'll likely never be able to ascertain its composition, but you will be able to determine its hardness. It will likely be like Linotype, so will be hard, light and cast large. You can always mix it with Wheelweight or pure lead.
 
Back
Top Bottom