1/2 boolits for lee hardness tester

[montana_charlie]

the lee is more accurate.

Really have you ever tried to compare the two on a known sample I just did it on Rotometals #2 pure lead known WW and some unknown alloys. CABIN TREE and best of all no wasting valuable casting and loading time trying to figure out how to file mill or machine a flat!!!

Did you know that the results from a Lee are directly related to the actual BHN number?
Did you know that the result from the Cabine Tree is a 'depth' which is correlated with the hardness listed for that alloy in an old chart ... which has been wrong for decades?

The Cabine Tree will accurately show the amount of variation in different alloys, but it really doesn't know the Brinell hardness number of any alloy, and what it thinks it knows, is wrong.

Let's say you test pure lead and 20-1 lead/tin alloy with your Cabine Tree.

If you are a good operator, you will come up with a correlation from the table that indicates BHN 5 for the pure, and BHN 10 for the 20-1.
Guess what! Both of those are wrong, and they have been wrong since before you and I were born.
Actually pure lead is BHN 4.5 and 20-1 is BHN 7.8.
The old chart also shows Tin at BHN 7 but it's really BHN 5, and 30-1 as BHN 9, but it's actually 6.6

One number on the standard chart that is correct is BHN 15 for Lyman #2 alloy. That's because Lyman did their own test when they developed the alloy, and THAT number got added to the chart that everybody relies on.

With so many readings being off by that much, how valid are any other 'hardness readings' you get from the table that comes with the Cabine Tree?

The Lee uses a scaled down version of the actual Brinell test to provide results.
So, it can only give an erroneous Brinell number if the operator uses poor technique.

CM

[edsmith]

[PanaDP]

I ran across a post somewhere, not here, can't find it again. But these little "can't see through them scopes" aren't a necessity, if you have a digital camera to snap a pic of the indent. You can measure in pixels, then convert pixels to inches, and you have a nice precise measurement. If I ever find it again I'll post more.

Then I take it you have a copy stand to facilitate measuring the exact subject distance and a collimating device so you can find the true focal length of your lens?

[montana_charlie]

Some guys have posted comments about using pretty low-cost digital microscopes, connected to a computer with a USB interface, and having an easy time of measuring 'dimples'.
CM

[miestro_jerry]

The problem with testing the hardness of boolits is the outer layer or surface of my boolits is harder that insides.

I use a industrial hardness tester that I use in my machine shop.

Jerry

[williamwaco]

Some guys have posted comments about using pretty low-cost digital microscopes, connected to a computer with a USB interface, and having an easy time of measuring 'dimples'.
CM

I use this one.
http://www.opticsplanet.net/celestro...icroscope.html


It calibrates exactly with my Lee microscope, and with my digital caliper ( using 3x binocular magnifier.)

And it takes about five seconds
And it is a really nice little camera.

.

[williamwaco]

Hmmm. Try filling a bottle cap. That will give you a "ingot" small enouth to fit in the press, and a flat surface (the open side) to test...

Hmmmm . . .


. . . . . . . . . . . .What's a bottle cap?




.

[edsmith]

william, there is at least 2 dummies on this forum, I am one of them, could you explain how to use the microscope to measure with. thank you. me and the other dummie thanks you.

[miestro_jerry]

You put a know amount of force behind a ball ended piece of steel and it does some type of indentaion on the metal being tested. The microscope has graduation on it and the size of the dent is directly in relationship to hardness of the lead.

Jerry

[357maximum]

A friend of mine that is somewhat smarter than I is simply fills up a spoon with alloy. He then tests the flat areas on that IG NOT . Most of us keep an old spoon around our casting area I bet.

[Gussy]

[QUOTE=montana_charlie;1636732]Did you know that the results from a Lee are directly related to the actual BHN number?
Did you know that the result from the Cabine Tree is a 'depth' which is correlated with the hardness listed for that alloy in an old chart ... which has been wrong for decades?

The Cabine Tree will accurately show the amount of variation in different alloys, but it really doesn't know the Brinell hardness number of any alloy, and what it thinks it knows, is wrong.

Let's say you test pure lead and 20-1 lead/tin alloy with your Cabine Tree.

If you are a good operator, you will come up with a correlation from the table that indicates BHN 5 for the pure, and BHN 10 for the 20-1.
Guess what! Both of those are wrong, and they have been wrong since before you and I were born.
Actually pure lead is BHN 4.5 and 20-1 is BHN 7.8.
The old chart also shows Tin at BHN 7 but it's really BHN 5, and 30-1 as BHN 9, but it's actually 6.6








When this chart was made, I used what was published as a norm for Brinell numbers.

Assuming you're correct in your numbers and even if the chart numbers are off, the tester will still tell you it's 20-1 or equivalent hardness. The tester is still correct in identifying a hardness. This is a "home casters tester" not lab equipment but it will still work and it is repeatable. You can just change the BHN numbers on your chart if you like and it will read as you like as far as the number in the BHN column.

How many people really need exact BHN?? Most need a hardness that works and a way to find out if they are repeating it. As other posters have said, a purchased alloy tested as advertised. That's about all you need.

Gus
Jim Cornaggia
CabineTree LLC

[Longwood]

I made a little ladle with a condiment cup that I make little ingots to test on. They read very close to the bullets cast from that melt.

I also made my own Cabine Tree copy and my own hardness chart using known samples.
I also made a super simple tester that works just fine with a dropped weight and a three foot long rod from Home Depot.

[AR-15 Cowboy]

When you sort it all out, the Lee tester is a good buy for the money, and eventually they will come up with a scope holder as an accessory for an optional price. They read these forums too.

[williamwaco]

william, there is at least 2 dummies on this forum, I am one of them, could you explain how to use the microscope to measure with. thank you. me and the other dummie thanks you.

Measurement is a built in function of this device.
You select Action / Take Measurement.

Then you click on two points on the photo and the program tells you the distance between those points ( In millimeters ) You must convert to inches.

They are not clear on this issue but for the measurements to be accurate, the item being measured must be located exactly in the opening to the barrel of the device.


.

[williamwaco]

A friend of mine that is somewhat smarter than I is simply fills up a spoon with alloy. He then tests the flat areas on that IG NOT . Most of us keep an old spoon around our casting area I bet.

Damn! Spoon. I have four of them in different sizes on my table at all times. Why didn't I think of that?


.

[357maximum]

Damn! Spoon. I have four of them in different sizes on my table at all times. Why didn't I think of that?


.

I feel your pain.......it was a definate DOH! moment for me too.