Lee Hardness Tester problem: measuring extreme material

[El Bibliotecario]

I used my Lee Hardness Tester the first time. Lead which I knew to be wheelweight tested in a common range, around 11-14 BHN. Apparently I was doing something more-or-less right. With extremely soft lead--easily scratchable, or stick-on wheelweights--and type metal, the rod would not rise flush with the top of the die. The dimple made by the partially raised rod measured outside the number range supplied with the instructions; that is, off-the-scale hard for type metal and off-the-scale soft for soft lead.

Given my inexperience there may well be an operator problem, but I thought I would ask.

[JBinMN]

Screw the hardness tester "die" in further down(into the press). You likely can also do this while the point is on the piece until it rises just above the tester "die". then move to a different spot on the piece of lead and re test so that the rod is at the top of the "die" like it is supposed to be for 30 sec..


Then you will be able to get an accurate reading.

G'Luck!

P.s. - I can't remember if the time to press is 30 sec. or a minute right now, and without going down to look at the instructions again. I just said, "30 secs". Use the time period specified in the instructions.

[JBinMN]

I just thought of what may be an easier way to describe how I set mine up to test.

Put the "die" into the press a short way & put the "shell holder with the crevice in it into the ram. Bring the ram up to its' top point. Screw the "die" down into the press until it is closer to the "shellholder with the crevice" that the lead would sit on, than the thickness of the piece of lead you are going to test. Then the rod that you have to bring flush to the top of the "die" will be sure to be able to move above the top of the die when you do the actual test.

In example, if the piece of lead you are going to test is 1/2 inch thick ( or like a bullet that is .50), then you would do the process listed above so that the tip of the hardness die is at about .45 from the shellholder w/crevice. Meaning the piece or bullet will be pressed in between the tip f the die & the shellholder /w crevice. Then when the piece of lead is in between, the post will rise to flush when you bring the ram up to test the piece of lead. ( if you pushed the ram up fully the post would rise to approx. .05 or so above the die until the lead allowed the tip of the die point to penetrate)

Hopefully I helped ya out.

[mdi]

I kinda think it depends on where you want to hold the press handle steady for a full 30 seconds. As long as the test sample will travel up/down in the press opening and doesn't hit anything, there isn't a real "setting". I screw my test thingy down so I can see the sample as it is tested. Other than that it really doesn't matter, just have enough travel to impress the sample and comfortably operate the handle...

[El Bibliotecario]

Thanks for the input. Screwing the die farther down allowed the rod to rise flush with the top of the die.

For soft lead I am still getting readings too low to be covered on the instruction sheet. I am assuming the Hardness Tester does not have the sophistication to measure an extensive range, and cuts off around 8. That's not a big issue in that pure or near-pure lead is pretty obvious.

What baffles me is that with type material, I am getting readings in the same range as wheelweights. I assume this is another operators problem, or a false assumption that all type metal is at least as hard as linotype.

[retread]

Type metal is used over and over in the printing process. The hardness of the type decreases in hardness by what ever alloy they mix in when the pour the pigs for the next use. Sometimes spacers and other lead alloys find their way into the mix. I have a number of pigs for a printer that sold out and they do vary in hardness.

Thanks for the input. Screwing the die farther down allowed the rod to rise flush with the top of the die.

For soft lead I am still getting readings too low to be covered on the instruction sheet. I am assuming the Hardness Tester does not have the sophistication to measure an extensive range, and cuts off around 8. That's not a big issue in that pure or near-pure lead is pretty obvious.

What baffles me is that with type material, I am getting readings in the same range as wheelweights. I assume this is another operators problem, or a false assumption that all type metal is at least as hard as linotype.

[Camper64]

Here is an expanded chart.

[El Bibliotecario]

Thanks for the chart, which confirms the readings I was getting of over .08 from obviously soft material. Also useful to know type metals vary in hardness.