Precision Matthews PM45 Tram and a New Vise

This would be what I'd consider if I were in the market for a Rockwell tester. It's the same unit as a Phase II (made by same factory) without the price tag.

http://www.wttool.com/index/page/product/product_id/18056/product_name/Precision+Hardness+Tester+(WT)&update_continue_shopping=true

... Just tossing that out there.

This is the Leeb I like. It's one of the few portable units that can accommodate different probes.




Ray



Tony Wells said:
I'd rather have a standard bench model Rockwell tester. It's a better fit for my parts. At least these days. Things could always change, but if I need a portable, I'll probably go with a Wilson or similar.
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Yeah, that's the style I am most comfortable with. Wilson, I believe made a portable Brinell machine that chained around large bars and read directly, no conversions. That is what a lot of larger distributors use. I had access to one, should have grabbed it. All you had to do is grind past the decarb zone and tale the reading. But then, until I get that Mighty lathe up, I plan on no large work, and besides, when I buy materials, I require MTR's, and don't stress too much about hardness. It's only if I have to buy annealed and locally get it heat treated. At some point, I'll get or build a furnace, but it will be smaller than something that will do a 10 x 96", so the benchtop will suit my purposes just fine. Plus there is always the test coupon procedure, acceptable to many customers with specific HT needs.

I'm not that familiar with the Leeb units.
 
Ray, For future reference, "odorless" mineral spirits take cosmoline right off... How do you like this mill so far?

John
 
Gotcha... you do much bigger stuff than I do.

BTW: Cant say from experience but, I found a site dedicated to heat treating and hardness testing and they claim Leeb is now the preferred method for QC inspection in 80% of incoming QA departments. That has slightly different connotation and significance but, it's really versatile and would suit my desires.

Ray



Tony Wells said:
Yeah, that's the style I am most comfortable with. Wilson, I believe made a portable Brinell machine that chained around large bars and read directly, no conversions. That is what a lot of larger distributors use. I had access to one, should have grabbed it. All you had to do is grind past the decarb zone and tale the reading. But then, until I get that Mighty lathe up, I plan on no large work, and besides, when I buy materials, I require MTR's, and don't stress too much about hardness. It's only if I have to buy annealed and locally get it heat treated. At some point, I'll get or build a furnace, but it will be smaller than something that will do a 10 x 96", so the benchtop will suit my purposes just fine. Plus there is always the test coupon procedure, acceptable to many customers with specific HT needs.

I'm not that familiar with the Leeb units.
Click to expand...

- - - Updated - - -

I was using some kero and the stuff was like a hard plastic. -Not really sure if it was cosmoline.

Anyhow, the mill? It's great and not a lick of problems in the last 4 (going on 5) years. Still trams out the same as day one. Really versatile and perfectly suits my needs. It feels more like a big machine than a small one if that helps gauge things...

Haven't used the mill vise yet. I'm in the middle of cleaning a tool cutter/grinder I picked-up a while back. It's a terrible day for it. Hot and humid as heck out today and the air isn't moving a bit. The fans are only blowing flys at me.


Ray

jgedde said:
Ray, For future reference, "odorless" mineral spirits take cosmoline right off... How do you like this mill so far?

John
Click to expand...
 
Ray, if you get a chance, link me to that site please.
 
Never heard of Leeb tester, but am familiar with the Shore Scleroscope; same idea, I guess, records rebound of a steel ball in a glass tube. Personally I am most familiar with the Wilson Rockwell hardness tester, have a bench model, it is capable of all the common indentation tests, except Brinell and superficial Rockwell tests, used on thin case hardening. And yes, I do have numerous test specimens to test calibration; one thing that can and does affect accuracy is the condition of the indentor (diamond or steel ball) a small defect can grossly effect the accuracy. I previously had a Wilson Rockwell tester that had a motor drive, which was trouble all the time, as the clutch did not function properly; I was having inaccurate readings, finally looked at the diamond with a high magnification glass, and sure enough, there was a small chip on the cone of the diamond; a hundred bucks and change later, the new diamond solved the problem; I sold it on e bay after I found a very nice manual machine.
 
Another often overlooked factor is the diameter of the test specimen, if it is a round bar and the test penetration is to be on the OD or side of the bar. All penetration style testers should come with a chart offering compensation factors to offset for the simple fact that it takes much less pressure to indent the specimen at the OD, and the force required increases as the penetration gets deeper. Of course, this is true for all tests, but due to the curvature, it is not a linear relationship of weight/depth/hardness. A rod 3/4" in diameter will check much softer than it really is because the penetration is deeper if measured from the actual OD rather than from a flat surface, which presents a uniform increase in force as the diamond or ball is pushed in. Some people prefer to grind a flat on the specimen, if allowed. Some parts are drawn with test points specified in areas where the penetration will have no adverse effects and can be ignored.
 
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