Testing BHN with the pencil set technique?

[capt.hollis]

Guys, I know this is in a sticky or discussion somewhere which I've read, but I cant seem to find the technique? Do you want the pencil lead as sharp as you can get it. Also do you use a magnifying glass for the initial inspection? How much of a scratch is the actual BHN? Any tips are appreciated guys.

[JWFilips]

I have tried a number of different quality ( or not ) pencils sets & it appears that Staedtler is the more accurate for the purpose.
I tried others which gave lower readings and also higher readings with known samples of lead & lead alloy.
The Staedtler's seem to be right on ( & I feel these can be trusted) to get you very close to the hardness you are testing.

[capt.hollis]

I have tried a number of different quality ( or not ) pencils sets & it appears that Staedtler is the more accurate for the purpose.
I tried others which gave lower readings and also higher readings with known samples of lead & lead alloy.
The Staedtler's seem to be right on ( & I feel these can be trusted) to get you very close to the hardness you are testing.Where did you get those JW? Thanks man

[JWFilips]

Got mine at the local "Staples" "you got to ask" since they are not with the standard writing implements & in the drafting section
12 pencil set in a a nice metal box... about $14 don't buy any other brand other then Staedtler ( ask me why! I have a few alternate brand sets if any one wants them cheap! they don't do what we want!)

[bangerjim]

It is a WAG......an estimate.......a dart thrown in the dark. There are several variables even down the brand of pencils!!!!!!

I have checked the process against my Cabine and Lee testers and it is "close enough for government work". In other words - plus or minus a bunch. Got the set of pencils at HobbyLobby (around $10) for a friend who is just starting out & cannot afford at tester right now.

That said, if that is the only thing you have/can afford, it will give you a very rough guideline. And that is really all we are after!

I assume you have copied the chart/s listed in the threads to use as a guideline?

If the pencil makes a "mark" in the lead, the pencil is harder than the lead. Keep trying pencils in order of hardness. When you quite leaving marks or "scratches" in/on the lead, you know the approximate-sort-of-round-about-almost hardness. Even with a premium tester like the Cabine, there is error and I run a test at least 3 times, each one on a new spot on the ingot. Or on another boolit. That is why I use the Cabine all the time and quit using the hard-to-use time-consuming Lee thingy.

You do not need a microscope or magnifier, as long as your eye sight is good. Just sharpen the pencils as if you were going to use them to write.....not a needle point or it will break too often.

Any other questions, fire away!

bangerjim

[capt.hollis]

It is a WAG......an estimate.......a dart thrown in the dark. There are several variables even down the brand of pencils!!!!!!

I have checked the process against my Cabine and Lee testers and it is "close enough for government work". In other words - plus or minus a bunch. Got the set of pencils at HobbyLobby (around $10) for a friend who is just starting out & cannot afford at tester right now.

That said, if that is the only thing you have/can afford, it will give you a very rough guideline. And that is really all we are after!

I assume you have copied the chart/s listed in the threads to use as a guideline?

If the pencil makes a "mark" in the lead, the pencil is harder than the lead. Keep trying pencils in order of hardness. When you quite leaving marks or "scratches" in/on the lead, you know the approximate-sort-of-round-about-almost hardness. Even with a premium tester like the Cabine, there is error and I run a test at least 3 times, each one on a new spot on the ingot. Or on another boolit. That is why I use the Cabine all the time and quit using the hard-to-use time-consuming Lee thingy.

You do not need a microscope or magnifier, as long as your eye sight is good. Just sharpen the pencils as if you were going to use them to write.....not a needle point or it will break too often.

Any other questions, fire away!

bangerjim Awesome, Thank You guys. So if I were to go to Office max, etc, Would I ask for the artist set of pencils or what would this set be commonly called just to avoid the confusion with the kids I know that work there? , lol.

[Ford SD]

Guys, I know this is in a sticky or discussion somewhere which I've read, but I cant seem to find the technique? Do you want the pencil lead as sharp as you can get it. Also do you use a magnifying glass for the initial inspection? How much of a scratch is the actual BHN? Any tips are appreciated guys.

Not sure if Im doing it right, But what Im doing is

remove the wood at the end of the pencil with a knife and use a file to square off the inside of the pencil (square)

then rub/ push pencil along the lead to be checked if it marks/ digs in lead is softer than the pencil
if pencil tries to polish lead, lead is harder than pencil

[eljefeoz]

It is a WAG......an estimate.......a dart thrown in the dark. There are several variables even down the brand of pencils!!!!!!

I have checked the process against my Cabine and Lee testers and it is "close enough for government work". In other words - plus or minus a bunch. Got the set of pencils at HobbyLobby (around $10) for a friend who is just starting out & cannot afford at tester right now.

That said, if that is the only thing you have/can afford, it will give you a very rough guideline. And that is really all we are after!

I assume you have copied the chart/s listed in the threads to use as a guideline?

If the pencil makes a "mark" in the lead, the pencil is harder than the lead. Keep trying pencils in order of hardness. When you quite leaving marks or "scratches" in/on the lead, you know the approximate-sort-of-round-about-almost hardness. Even with a premium tester like the Cabine, there is error and I run a test at least 3 times, each one on a new spot on the ingot. Or on another boolit. That is why I use the Cabine all the time and quit using the hard-to-use time-consuming Lee thingy.

You do not need a microscope or magnifier, as long as your eye sight is good. Just sharpen the pencils as if you were going to use them to write.....not a needle point or it will break too often.

Any other questions, fire away!

bangerjim

Hi Banger,
Thanks for the above.
I seem to be getting about 11-12 and 8-10 for 2 of my alloys.
As per Bumpos XL sheet, they should be 10.something and 14
Close enough I guess, gives me a fair idea.
Cheers