rockwell testing blades

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pollock9131

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Feb 26, 2010
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Can anyone out there tell me what type of anvil is used to place a knife blade on to hold it level, so you can do a rockwell hardness test on it? Thanks.
 
Thanks for responding Kevin. I still don't understand though. The manual says the test piece must be level and when the knife is on a flat anvil it is no longer level because of the blade grind. I want to test near the edge of the blade, which on most of my knives is approxately a 10 deg. Angle. I appreciate any help you can give.
 
pollock9131 said:
Thanks for responding Kevin. I still don't understand though. The manual says the test piece must be level and when the knife is on a flat anvil it is no longer level because of the blade grind. I want to test near the edge of the blade, which on most of my knives is approxately a 10 deg. Angle. I appreciate any help you can give.
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You're not going to get an accurate reading on a beveled piece. Period. If you'd like to check the HT of your process, include a small, flat coupon of steel in your Ht process and run it exactly the same as you do the blade. Then, you can grind and test the coupon for hardness. Or, you could test on the ricasso or tang of a fully hardened (ie. not edge quenched) piece.

-d
 
I edge quench most of my blades. Is there any way to check the hardness at different points on the blade? Supposedly Wayne Goddarrd does, but I don't know how.
 
Now is the time that the conversation usually switches to files. You cannot take an accurate Rockwell reading on and edge bevel, but there are Rockwell files on the market that can take readings anywhere. This however will not be an accurate replacement for a Rockwell test, but will be in the approximate ball park. The Rockwell test measures penetrative hardness while files only measure scratch hardness.
 
I will be doing the test before the final sanding is done. So there will be no dimple left to see!!!
 
They make an anvil called an eye-ball anvil. it has a flat spot on the ball, and the angle can be adjusted, then tighten the jam nut down around the ball to hold that angle. The problem is it costs about $225.00 and will not fit my metric acme threads. There must be another way! Does anyone know if placing a metal wedge between the anvil and the blade to bring the blade back up to level would effect the accuracy of the test?
 
You could periodically sacrifice a blade, have it sectioned through the blade, then measure from spine to edge that way.
 
Does anyone know if placing a metal wedge between the anvil and the blade to bring the blade back up to level would effect the accuracy of the test?
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I am no expert on rockwell testing but it seems like it would work as long as the setup stays stable. Can you practice on a scrap blade?
 
Sure. I occasionaly have one crack when quenching and can use them as test blades. Thanks for responding, I'm new to the forum.
 
No problem I am curious about your results. I plan on edge quenching and doing fully hardened blades. What type of tester do you have?
 
I bought mine from Enco. It is an import but supposedly very accurate. The people at mid way USA (gun smithing supplies & parts) use the same tester. As big a company as they are, I'm sure they could use which ever one they wanted. I believe the model # is HR-150A. I'll let you know how things work out. I sell mostly straight blade hunting knives and want them to be as durable as possible, but with a hard edge. Most people are pretty rough on hunting knives, and I want mine to have a soft flexable spine.
 
pollock9131 said:
I bought mine from Enco. It is an import but supposedly very accurate. The people at mid way USA (gun smithing supplies & parts) use the same tester. As big a company as they are, I'm sure they could use which ever one they wanted. I believe the model # is HR-150A. I'll let you know how things work out. I sell mostly straight blade hunting knives and want them to be as durable as possible, but with a hard edge. Most people are pretty rough on hunting knives, and I want mine to have a soft flexable spine.
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Have had the same one for a few weeks now. seems to be a pretty accurate and consistent benchtop tester. It's on sale too for $695.00 from the usual $942.00 or something like that!

if you want to do a C scale test, you gotta use the diamond penetrator tip, and not the ball thing that comes installed on it.
 
I just sent my Enco tester back as there was something wrong with it. Readings all over the place and couldn't be adjusted. Must have been a bad one. Not sure I want to chance another.
 
I have checked several punches with slight angles and odd shaped parts in tool and die. I would not reccomend using a wedge. The blade could slip causing a side load and there goes your penetrator. A flat ground blade should not pose a problem, because of the penetrator depth. But you will have that nasty little mark from the test. Another option is an optical type tester. It has a ball penetrator kind of like an automatic center punch. Then you look through a scope that tells you the hardness. I use one quite a bit for checking large pieces that won't fit on a bench tester. They are accurate I would say +/- 2 points. And they do read in the c scale, in the low 60's. The ball penetrator on bench models is not designed for anything in common knife hardness.
 
Thanks for all the feedback! We'll figure something out. I spoke with Wayne Goddard (Blade Magazine, $50.00 Knife shop, Wonder Of Knife Making) in case you guys don't know of him. He said he uses a anvil that is only about 1/4" diameter. I guess the smaller diameter anvil reduces the degree of angle, since not as much of the blade is resting on it. You guys are giving great feedback! Keep up the good work, I sure appreciate any help I can get!!!
 
If I was that concerned about it I would have an anvil or set of anvils made with the corrected angle(s) and a jig that connects to the unit. If jig had a shoulder that could be adjusted to hold against the spine it would keep the blade from sliding. Another possibility would be a good sized rare earth magnet beside the anvil to hold the blade in place.
 
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