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BLACKHEART
09-16-2002, 11:17 PM
My wife gets mad at me because, she says I tell all my secrets & then others take credit for them. This is one of those things that I have "stumbled" upon, that I'm willing to share. Give me some feed back on this & the other ccb posters might get some good from our observations.

OK, here it is. I have been looking for a way to test the hardness of tips, one to the other, in a box. I HAVE FOUND THAT IN ANY BOX, THE THICKER TIPS ARE THE SOFTER ONES. Say you have a Lepro that measures .295, it will SEEM SOFTER, as you sand the back, than one that is .245. They all seem hard when you start to sand, but after you get through the initial hard surface you'll notice the difference in hardness...JER

Chris Cass
09-16-2002, 11:24 PM
Hi Jer,

In Vegas this yr. at the BCA tourney. This guy had a cue stand and advertised LePro Tips in 5 different hardnesses. I talked with him very briefly. He told me they were measured with a Durometer or something like that. I was amazed. I didn't know there were 5 hardnesses? I've only heard of 4 ever. Could this be true?

Regards,

C.C.~~thanks for the tip. no pun intended.

Rod
09-17-2002, 01:40 PM
Jer,
That does make sense unfortunately all I have is fibre backed tips. It helps to know that though when your sorting through tips. I have checked them by sanding the crown but the ones I use now are very consistant and hard.

Troy
09-17-2002, 03:27 PM
Interesting Jer... I'll pay attention to that suggestion.

I bought a Durometer (Type D) on E-Bay for $50 (PTC, Model 307L), very handy..... I still get a few Le Pro tips that "blow up" after installation, but not as many now.

I found that LePro's that sand "hard" also measure "hard". The range for LePro is +/- Durometer 65 to 80, but I can't attest to the accuracy of my instrument, so it's all relative.

Troy

<blockquote><font class="small">Quote: BLACKHEART:</font><hr> My wife gets mad at me because, she says I tell all my secrets &amp; then others take credit for them. This is one of those things that I have "stumbled" upon, that I'm willing to share. Give me some feed back on this &amp; the other ccb posters might get some good from our observations.

OK, here it is. I have been looking for a way to test the hardness of tips, one to the other, in a box. I HAVE FOUND THAT IN ANY BOX, THE THICKER TIPS ARE THE SOFTER ONES. Say you have a Lepro that measures .295, it will SEEM SOFTER, as you sand the back, than one that is .245. They all seem hard when you start to sand, but after you get through the initial hard surface you'll notice the difference in hardness...JER <hr></blockquote>

SpiderMan
09-17-2002, 03:58 PM
Chris,

I would expect difficulty in getting an accurate durometer reading of a LePro without first sanding off the hard shellac coating. Same with WB tips. Those with exposed surfaces such as Triangles, Elk Masters, Triumphs, etc, would be accessible to the measurement, though.

SpiderMan

<blockquote><font class="small">Quote: Chris Cass:</font><hr> Hi Jer,

In Vegas this yr. at the BCA tourney. This guy had a cue stand and advertised LePro Tips in 5 different hardnesses. I talked with him very briefly. He told me they were measured with a Durometer or something like that. I was amazed. I didn't know there were 5 hardnesses? I've only heard of 4 ever. Could this be true?

Regards,

C.C.~~thanks for the tip. no pun intended. <hr></blockquote>

SpiderMan
09-17-2002, 04:02 PM
JER,

That makes sense, particularly if you assume that all tips in a box came from the same original hide. Each tip started with the same characteristic thickness and density, so the different finished heights could represent differing amounts of retained compression.

I've always wanted to do a similar measurment, but actually calculate density by dividing weight by volume. Volume would be calculated from height/diameter measurement. Haven't done it yet, but one of these days when I buy a digital scale for my reloading bench I will.

If someone else wants to do it, I'd gladly share the credit /ccboard/images/icons/wink.gif

SpiderMan

TonyM
09-17-2002, 04:53 PM
"I didn't know there were 5 hardnesses? I've only heard of 4 ever. Could this be true?"

That depends on the resolution of the equipment, and the scale of the hardness range. You could make as many steps as you wanted, and claim a hundred different hardnesses if the resolution (and repeatability) was fine enough.

Actually, there is no industry standard for tip hardnesses, so anyone can make up their own range and scale that they want.

As to Jer's comment, I noticed the same observation. But it doesn't always hold true, even for a specific box of tips. Sometimes, the tall ones are hard as well!

I've dropped them onto glass and listened for the sound. The ones that go "thud", are soft, and the ones that go "plink" are hard (usually).

Actually, how hard the tip is out of the box is of little use to me. I like to pre-compress the tips (often with a vice) and then check the hardness. This tells me how the tip will behave after break-in. I detect more dead tips this way, then measuring the hardness right out of the box.

Of course I also bounce the shaft on a concrete floor after installation as a final test (tip first, of course!). If the tip goes "thud" at that point, I bounce it hard for 50 to 100 times, and if it doesn't improve, I take it off. It's dead. But if it bounces well and high, and goes "boink", then it's a keeper.

How do you like my sound effects?

I think that what we really want to measure is the tip's Coefficient of Restitution, not it's hardness. (we infer the CoR from the hardness).

The bouncing method could do this, if you dropped a known shaft from a known height and measured the rebound height.

Also, you could set-up a plastic tube over the tip (mounted on a metal anvil with dbl sided tape) and drop a metal ball onto the tip and measure the rebound height.

More height = harder tip or higher coefficient of Restitution.

Tony
-rambling a bit now......

BLACKHEART
09-17-2002, 10:40 PM
I do close to 2000 repairs a year &amp; most of them are tips &amp; ferrules. I needed a quick test for the out of the box tips &amp; this one works good for me. I live in an area where 1/2 of the tips I do are medium or soft. So puttng them in a vice might work to make them harder, but I need just as many of the others. Tips can dry out,too. Keep your tips in the box &amp; a plastic bag might be a good idea, if you have a box &amp; only use a few a year...JER

Chris Cass
09-18-2002, 01:02 AM
Now your killing me Tony. HAHAHA If you think I'm dropping my S.W. shafts your crazy. HAHAHAHAA

Thanks Tony, your a very smart man and I agree with your theory. I've shot with LePro tips for 25 yrs. I've had a lot of really good yrs with them till the last 8 or so. I don't know what the problems were? I seemed to find all the bad ones in the batch. Since then, I've moved on to a harder tip. Thanks for the information.

Regards,

C.C.~~CoR, that makes sence.

SPetty
09-18-2002, 07:48 AM
<blockquote><font class="small">Quote: TonyM:</font><hr> Of course I also bounce the shaft on a concrete floor after installation as a final test (tip first, of course!). If the tip goes "thud" at that point, I bounce it hard for 50 to 100 times, and if it doesn't improve, I take it off. It's dead. But if it bounces well and high, and goes "boink", then it's a keeper. Tony<hr></blockquote>Hi Tony,

How does this bouncing on the concrete floor compare to hitting balls? I've read that a lot of people won't break with their playing cue because of the risk of damage to their shafts and ferrules. Isn't slamming a shaft against a concrete floor much more punishing for a shaft than hitting a cue ball? Just wondrin'...

TonyM
09-18-2002, 10:47 PM
Think of it like this:

A ball weighs 6 ounces.
A shaft weighs 4 ounces. Bouncing the shaft on the floor doesn't really put any more stress on it than hitting a ball. And you don't need a table, and you can get a nice centerball hit, with similar speed in a hurry, in a controlled enviroment.

I've never found that bouncing a shaft can damage either the tip or the shaft.

It can detect subtleties like cracked ferrules or joint collars though (makes a "clank" sound).

Tony