# Hardness Testers - Rebound Type -vs- Traditional Indentation



## countryguy (Jun 8, 2015)

Hi all;   The son and I are thinking of taking some of his heat treated items out to be tested.  We see there are many methods and options offered.    Anyone have experience in the rebound type testers -vs- the usual indent types?   

We want to test his 1/4" plate tactical type axes.  Rebound required mass to function we hear and we did not know if several axes could simply be stacked? Or will the lab/co. simply plop a hunk of steel under?   Wondered if this would skew results.
TIA 
CG 

some info from Wikipedia on each: 
incent: http://en.wikipedia.org/wiki/Indentation_hardness
rebound: http://en.wikipedia.org/wiki/Leeb_rebound_hardness_test

Some sites: 
Leeb: http://leebhardnesstesters.com/port...gf4aId3k_aXNW14IJ0NVrsd0t_zr5SNe_8aAiqv8P8HAQ
indent -


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## John Hasler (Jun 8, 2015)

https://www.gemeasurement.com/sites/gemc.dev/files/hardness_testing_faq_english_0.pdf

Look at FAQ 5.


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## Holescreek (Jun 8, 2015)

Before I bought my Wilson hardness tester I had the same dilemma.  My advise is that you call around to  find a local shop that would do it.  Every machine shop I've worked at had a Wilson tester to verify outside heat treated components were in spec.  It doesn't take a minute to test each part.  I does have to be bare metal (no paint) where the indenter touches.


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## AJB (Jun 9, 2015)

I've never hardness tested but the Ames portable units always looked interesting and I've seen some sell on EBay at reasonable prices.  Maybe someone can comment on them as well.


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## Flammable_Solid (Jun 9, 2015)

I've used both.  The rebound testers are ok if you want an approximate number and have goodnsurface conditions.  They also do not mark the parts.

All of the other hardness tests put a physical indentation into the metal and require certain dimensions with regard to thickness, flatness, and distance from an edge (I don't recall the ASTM soec off the top of my head for hardness testing).  

If the finished part can't be marked with an indentation, use a test coupon of similar dimensions to verify hardness.  Or sell the hardness indent as a "verifiable mark of quality."


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## tinman1950 (Jun 9, 2015)

Holescreek said:


> Before I bought my Wilson hardness tester I had the same dilemma.  My advise is that you call around to  find a local shop that would do it.  Every machine shop I've worked at had a Wilson tester to verify outside heat treated components were in spec.  It doesn't take a minute to test each part.  I does have to be bare metal (no paint) where the indenter touches.


Hi, I'm new to this forum and I need some help. I have a Wilson hardness tester but I am missing the weights. I was wondering if anybody can help me replace these weights one way or another, thank you!

Sent from my Z970 using Tapatalk


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## Holescreek (Jun 9, 2015)

tinman1950 said:


> Hi, I'm new to this forum and I need some help. I have a Wilson hardness tester but I am missing the weights. I was wondering if anybody can help me replace these weights one way or another, thank you!
> 
> Sent from my Z970 using Tapatalk



I got a lot of extra "stuff" for a Wilson. Probably a whole set of weights a platen or two. I'll check in the attic and see.


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## tinman1950 (Jun 9, 2015)

Thank you very much

Sent from my Z970 using Tapatalk


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## Flammable_Solid (Jun 9, 2015)

Here are the hardness specs:

ASTM E10 Brinell Hardness
ASTM E18 Rockwell Hardness
ASTM E140 Hardness conversion tables


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## countryguy (Jun 9, 2015)

Great idea on the "mark of quality".   Nice Touch FS.      your reply is just what I was looking for.  someone who's used both and has seen the results first hand.   The Surface conditions seem almost mirror like for the Rebound.   I'm now moving the Son away from rebound and into the $$$$  Wilsons and such.       I do want to read the FAQ's on the post from John.    Heading that' Away.  




Flammable_Solid said:


> I've used both.  The rebound testers are ok if you want an approximate number and have goodnsurface conditions.  They also do not mark the parts.
> 
> All of the other hardness tests put a physical indentation into the metal and require certain dimensions with regard to thickness, flatness, and distance from an edge (I don't recall the ASTM soec off the top of my head for hardness testing).
> 
> If the finished part can't be marked with an indentation, use a test coupon of similar dimensions to verify hardness.  Or sell the hardness indent as a "verifiable mark of quality."


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## Flammable_Solid (Jun 10, 2015)

FYI - Wilson is just the brand of the machine.  You will need to know what specific hardness tests a machine is capable of and which indenters to get with that machine.  Some machines can only do a certain test, some can do multiple types.  Also, figure out on the design of the axe where you want to check the hardness at and if it meets the requirements for thickness, flatness, parallelism, from the specs I listed earlier.  

For what hardness testers cost and what it costs to keep them calibrated, most people just get parts tested at an outside lab.


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## Tony Wells (Jun 10, 2015)

Out of the literally thousands of tons of various materials I have had heat treated, NONE of the HT'ers use rebound testers. You have to wonder why. One reason I can think of is the decarb layer. Not all materials have a significant decarb zone, and it can be virtually eliminated by controlled atmosphere so it's not always an issue. Many finished parts do not allow penetration marks, hence the practice of a test coupon. This also can be kept for future reference in case of a squabble with the customer. Most of the forgings and hot rolled Q&T has a considerable decarb layer, and this must be ground through leaving a reasonably flat area to test. I've used a chain-on tester for large diameter stock, and several benchtop testers, but always following strictly the ASTM guidelines applicable to each hardness range and material type. There is actually quite a bit involved in making legitimate hardness tests.

All that aside, the hobby machinist probably doesn't need all that traceability and super accuracy stuff. A rebound tester is not a new idea, and is acceptable in many cases. If you examine your needs realistically, and it meets your requirements, you can sure save some money.


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## countryguy (Jun 11, 2015)

Thanks for all the good feedback folks.  We're heading up to the local reseller/Lab place (Sun-Tec) near us.   Owners Son is going to have us bring up the Kids stuff and we'll see what we can do.   Nice guy to offer!    To ames units look really cool! But they seem scarce on the used front. My final 3cents is that so many used and so many unknowns from  the ebay and 'refurb' places-   We're in no rush. Just wondering, learning, and checking into things.     Thanks again, CG.


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