Most economical/accurate hardness test

I would prefer a bench top model, but even the machines I could afford were prohibitively expensive to ship cross birder to Canada.
 
I sold this one a couple years ago for $300 or $400, can't remember exactly. It was accurate and worked fine.

 
Thy still make that tester don but it's blue now, made in India. Never used on but like was said befor thy are simple machines.
 
BKT said:
No reason to doubt it. I have a digital oven and parks 50. Its really just piece of mind I am looking for, which is why I have a hard time investing $1500 in a machine that wont do anything but help me sleep better. I just hear those stories about that one off steel that wont harden or a bad batch or something that I would never want to leave my shop. I do the file test after quench but I was curious about more accurate ways.
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You are correct!! If you want to know the hardness you need a good tester (a 2nd hand in good condition is right), no shortcuts.
That said, you can test your edge and have a nice feedback, so you can know if the knife is performing well out of your shop... a lousy edge will be a lousy edge regardless the hrc number.
 
Don Hanson III said:
I sold this one a couple years ago for $300 or $400, can't remember exactly. It was accurate and worked fine.

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Mine is made in Italy, but it is exactly the same machine, aside mine has the screw telescopic cover and also a depth stop for the penetrator to be used if one wish to preset and fix the preload for a batch of readings.
It is accurate within an half HRC
 
How hard is it to repair/calibrate these things? Many I see online are being sold as "untested" because the owners dont know much about them. Am I walking into a money pit when purchasing one of these in unknown condition? Its a Wilson I am looking at.
 
Most untested means they don't know how to operate as in how much pre-load is required during test. If you can locate the model number and manual you can easily operate this equipment. The most important part is the Diamond Indent they are not cheap and most used equipment sellers can't tell you if it's good or bad. Ask where it purchased from like a machine shop that closed or a garage sale?! There are some excellent units out there that have years of shop crud on the exterior that does not affect their accuracy.
 
BKT said:
How hard is it to repair/calibrate these things? Many I see online are being sold as "untested" because the owners dont know much about them. Am I walking into a money pit when purchasing one of these in unknown condition? Its a Wilson I am looking at.
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Busto covered it good. Wilson is one of the best and simple. Make sure it has the weights (150g) & the diamond. But the diamond point can be bought on ebay fairly reasonable. Weights are usually very expensive.
 
First one I bought was a Superficial tester, read in B scale. No good for us knife makers. Make sure they read in C scale.
 
I wanted to add some notes here for people looking to purchase used testers.

I called Brystar Metrology Tools today for some information. I ordered a hardness tester on ebay and it came broken but thats another story.

Anyways if you are looking for a Wilson tester make sure it comes with weights. He said the weights you need to test C scale will be in the 150 kg range and you will need all three. Different models use different weights but new or used ones as a set cost $400+. I have looked for calibration blocks and they seem to be $75+ for each one. If you purchase one of these used testers, I would make sure that it comes with everything....weights, calibration blocks, brale indenter....or it seems the cost of buying used does not make up for the risk as you will have to purchase additional parts.

To repair mine, calibrate it, and shipping would have been around $1500. So from this experience I have concluded I will probably heat treat a sample, send it off to have tested, and just order some files or chisels to test with until I come across a killer deal I am more confident in.

Just wanted to add my experience here for others in my situation.
 
Just a clarification for those not familiar.

The weights are what loads the penetrator. They hang on the back of the tester, usually. They DO NOT weight what is marked on them. A 150 KG set weighs maybe 10 KG. THey are on a lever that multiplies the weight load. One reason everything inside needs to be in good condition, clean, and oiled is the lever system will not deliver the correct 150KG load if there is dirt causing friction or anything bent.
 
Thanks for that Stacy.

Another side note...I called Peters today and they said they would hardness test some samples for me. I live in a rural area and the only machine shops I have around here dont do hardness testing. So I will probably just HT a couple pieces of steel and send them off to verify my practices are sound.
 
I see the reasoning for just sending off or having a local machine shop doing the RH test. BUT that assumes that my local machine shop which readily admits it hasn't been calibrated for years is accurate. Then if I verify temps of my heat treat oven and tempering oven with temp sticks it sure would be nice to be able to check hardness after HT and after tempering. So is the $700 grizzly model totally unreliable or not worth the money? I could justify something in that price range but not $2500. Buying used seams like a crap shoot actually. I've been burned too often buying used and wish I'd just bought new to begin with. Just curious.
 
The test blocks are a measure of reliability and should be used to verify prior to testing. I can see why people over look the need to check their instrument in a machine shop they are only looking for "Ball Park" numbers where as we are looking for a specific HT number to quantify our working blade hardness. Test Blocks are sold in varying hardness as well as "A-B-C" scale. A test block comes from a NIST certified source with documentation to track it's quality so a 61 +/-.05 block should read that on the test. I do two tests to verify the technique before testing a batch of blades and I take my time.

I believe the Grizzly Model will operate just fine remember to pre-test since you will most likely not do RC testing every day. I purchased my Wilson/Rockwell from a GSA auction since I knew we were replacing the instrument where I worked at NASA. At auction it was more than the price of the Grizzly.
 
Just picked this up today for $100 from a retired machinist. I've been looking for a hardness tester for over a year now in my area. Not much luck until now. It works and seems fairly accurate. Had no idea these even existed. Before this it was a file and brass rod test.




 
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I had been looking at this type of tester and from the reading it seams to be quite picky and just gives you a ball park
 
To the poster asking about the Grizzly hardness tester - that is the HR150A that is sold a number of different places. There are a "blue million" of those HR150A testers in use and are a very valid tester. The specs on the tester are 2 Rc points, which I understand is very similar to Wilson and Rockwell testers. The repeatability is less than 1/2 point.

The diamond penetrator is currently selling around $11 to $13 shipped from China or India sources. I purchased one about a yr ago when they sold in the $30 range just to have a spare. I could not tell the difference in looking nor in use between the one ordered and the unit that came with the HR150A..... remember, it's made in China also.

Ken H>
 
I see your in North Ga, there are a lot of Georgia Custom Knifemakers Guild guys up your way, heck you may even be one of us, not sure about the forum name. There are a bunch of us with hardness testers and while I can't speak for everyone, I don't mind testing some blades for you. I have got to the point to where unless I'm trying a new steel or heat treat regimen, I only test like every 5th blade or so, if that often. If you have a good recipe down and can repeat it, you should get the same results every time. Anyway, hit me up if you want me to test some blades for you.

-Adam
 
The test piece of metal that it comes with has "44 -+ 1.5 R.C." etched on the side. Once it's adjusted (uses fluid) it cosistently hits the test piece R.C. And I'm guessing the 1.5 plus or minus is the accuracy range. For $100 I figured it'd be better than what I was doing before or files. Which was going to be my next choice.
 
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