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I Forge Iron

Rockwell Hardness Tester. Model HR-150A


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25 minutes ago, jlpservicesinc said:

Anybody serious about their craft can come up with the funds to buy one. 

I see your point, but this depends entirely on what you mean by "serious about their craft". I, for example, am very serious about improving my skills, challenging myself with projects and techniques that I've never previously attempted, and (perhaps most importantly) doing everything I can to support other smiths in their own individual journeys as craftspeople and artists. However, as someone who enjoys making the occasional blade but otherwise has no interest in becoming a professional bladesmith, I have neither the need nor the budget (or indeed the shop space) for a hardness tester of any variety.

That said, if I were a professional bladesmith or production toolmaker of some other variety, I would certainly consider getting a tester as an objective means of guaranteeing the quality of my product and of monitoring my progress within that craft.

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Unfortunately Hardness is only one of the criteria for a superior blade; personally I'm of the "doesn't take a diamond hone to sharpen" school for my personal blades.  Weight and flexibility factor in too.    It's nice that when a maker claims a particular HRC value they can back it up though!

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JHCC.  Someone always takes offense at something..   (Well, what do you mean? )..  Your talking 3 different things..  Skill, knowledge, and implementation.. 

the question becomes your own to answer..   Are you serious?   Are you selling an item that you want to know the Hrc value and then pass this information along?  (Known quantitative information) Of which Hrc will vary some from tester to tester.. 

Do you want to make tools (hammers, axes, swords, knives, punches, etc, etc. ) and know what their hardness is?  (if you are happy using files to verify then that's the level of precision you are ascribing to..)  Nothing wrong with those for a quick, down and dirty test.. 

And lastly..   Which for me is part, or more so the learning aspect..   

Becoming sensitive enough with a hand file to know about what the hardness is with just this simple tool based on how it slides or digs compared to known samples I have tested 100's of times. 

Being serious about "Craft" vs "Knowledge"  are not the same things.  

Being able to implement those skills in a real world environment any given day or time.. 

And of course the funniest part of it all.. Is self retrospection..    "Serous about craft" means exactly what it means for each individual. 

My definition is based on my own experiences and what I find to be important which can and does differ by a great many..  (Do you have someone you respect and want to idolize in metal working)..  Then their methods will find favor in your own thought processes and you will use that knowledge until you find or see something else that speaks to you louder..

As to "Trying different things to improve"..    That is great..   I'm super excited for you and happy.. :) You have gotten around and worked with some talented people.. Your amazing..  Mucho respecto.. 

I learned a long time ago..   The base line skill sets once learned  are all there is..  The only thing that changes is how I apply them.  (trade, artist, etc, etc. It's how the person thinks about the material in their own unique way)..    Fitchburg was frustrating because Ellen Durkan was the judge.. No real set measurements and told to go wild within reason. (But also having a set time frame).   I never do art..   So, had to adapt but also found it rewarding to try..  Fun really because it's not something I would do on my own.. 

People ask me all the time what is the hardest thing to make...    My answer is..  Nothing, they are all the same..  Some items just take longer than others.. 

Same skills, same methods, etc, etc..  

This coming from someone who used to be a (LOL) professional many years ago and somehow still get lumped into being a professional..  

I'm nothing but a "Has been"..    So take what you want from this..   

Something to chew on? Or dismiss..  Its up to you.. 

The Wearable art or 3rd session.. I only looked at it as a 2D item..  No side view.. Turns out it's a 3D item and I added in a hinge..  :) I can wear it but not what Ellen was looking for. 

Not bad overall for someone who hasn't really forged since last February..  


 

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Thomas..I like it.. 

Much more then simple hardness.. Or max Hrc value..  But it's important for someone not really understand the the relationship's between, hardness, toughness and edge retention.  (grain size, type of steel, hardness characteristics). 

I leave my hinge cold chisels extremely hard with barely any temper at all and very thin..   

And Leave my felling axes softer so a file will just start removing metal. 

I radially harden my hammers so the centers are as hard as can be (file skates) with nearly no temper but purple around the edges.. (file just starts to grab)

Depending on the blade profile on a knife will determine the blade geometry based on use as is the temper. 

All good fun. 

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IIRC Frank Turley used to draw the temper on hammers with a steel ring that would be heated and applied to the outside of the face to draw the "edges" and leave the center much harder.    I actually ran across a pair of tempering tongs at a fleamarket that can be used to temper blades, either along the spine for single edged blades or on the center ridge for double edged blades.

One of the joys of "custom" work is being able to do differential hardening and differential tempering to suit various intended uses of an item.   Hope you get the hole in the wall glazed before the snow starts drifting in!

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I think a lot of this discussion is about keeping testing in perspective, with the variableness in properties sometimes a benefit, sometimes not. Someone in the upper reaches of this thread mentioned that files would be next to worthless on layered, pattern welded blades. Wouldn't the same be true of any commercial hardness test? They typically only test one spot. 

My dad was in drilling most of his adult life. He told the story of how he found a casing that had "Hydrotested to 2000 PSI" freshly stenciled on it. Right in the middle of one of the zeroes he found a hole through the pipe wall! Did they pencil-whip the test? Not necessarily. A speck of oily grit might have plugged the hole during the test. It was enough for him to move to full-scan EMI testing. 

I wouldn't mind having a good hardness tester, but the ultimate test, as others have implied, is in the usage.

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In my MatSci class way back when one of the examples of stress concentrators was a part that was tested and then stamped as having passed---the stamp was a stress concentrator that resulted in the part failing in use!

Part of this discussion is there is not ONE BEST WAY to do a blade.  Unfortunately as there is a lot of folks trying to make a living making and selling blades there is a lot of hype out there as to why *their* blades are better than others!   [Deleted some egregious examples of hype from decades back in the blade world...Let sleeping dogs lie!]

Funny thing is that I end up making some accurate historical items with steels I know are not as good as modern ones; yet they do their job to the "standards of the day".  I've come to the feeling that design pays a major part in a blade and all those folks heading out to the frontier with basically a butcher knife  were not necessarily wrong...

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I've been teaching mechanical design for a number of years. Testing is good and necessary at times because it establishes a baseline or a starting point and gives a general reliability within reason. No design engineer or manufacturer (here the blacksmith) can account for all the variables possible or conditions for an item to fail. We test our products in multiple ways - test data from standardized tests (hardness for example), tensile test data, actual use test conditions, etc. No single test guarantee's a success item. I try to impart to my students for success for part design that you use all the tools available and testing in one such tool.

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The book on Statistical Process Control, by Shewhart, is full of examples of companies testing stuff; but the tests did not increase the quality of the product as they were using the wrong tests! (Or using the date wrongly.)    What *should* we be testing and what changes *should* be made based on the results are essential factors in the design of testing systems!

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Purple Bullet..   This thread started out as me showing a new toy I picked up for the school..  I actually have 4 HRc testers and a vintage 1921 Brinnell tester.. 

It's to show people how metal selection, proper grain refinement, heat control, forging at the proper temps and tempering play into the choices for the desired end product. No matter what it is. 

As a long time smith and long time hand tool user all of my tools are harder then what I would sell or let others use.  Many of my tools if used improperly will shatter as they are designed only for 1 purpose.. 

Anyhow. a tool like any other is just that.. A tool.. 

It's up to the person using the tool to use their brain, to use the tool appropriately.. 

This is actually why I started the videos and why I am starting the school.  

PHD forge.   No, one can not account for every given scenario and why most will just make a general purpose tool with general purpose hardness and temper. 

Everything I make is custom.. So everything gets hardened and tempered based on the use as well as the user. 

Giving a fine cutting tool like a thin bladed felling ax to a newbie is a recipe for disaster so one must account for this.. 

Like anything stuff happens but it's up to the user of any given tool to understand and accept responsibility for the correct use.  

I have never chipped a blade on any of my axes.. Nor have I ever broken 1 of my hinge chisels if used properly..  

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2 hours ago, Purple Bullet said:

 Someone in the upper reaches of this thread mentioned that files would be next to worthless on layered, pattern welded blades.

its actually the other way around, the machine is next to useless on PW steels.  Files are preferred for pattern welded blades, the Rockwell tester only gets one spot of that one layer, the files will allow an average reading

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Brinell testers use a 10mm ball as the indenter, as stated early it leaves a large depression. It is also not recommended for thin materials due to distortion of the test piece skewing the reading of the diameter measurement at the lip of the indentation.. The Rockwell tester depends upon the scale used and uses different types of indenters. For the C scale it uses a diamond tip. This is very small and I think would not be suitable for PW steels, because you may not know if the test site is in the soft or hard material layer. 

JLP I agree with your reason for having the tester at your training facility, good educational tool. I also agree with the basic idea of the user accepting responsibility for the use of a particular tool. Unfortunately many users do not. Hence, product liability lawsuits.

I am teaching at a different college. My old school had three Rockwell and one Brinell testers. My current place has none. Rockwell testers are easy to use and direct reading. I do have a set of hardness files for now.

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Its the age factor of the old Tinius Olsen that makes it worth having.. That and the fact its hydraulic for a machine from 1920's. It's missing the weight bar system.. I'll have to reproduce it if possible. 

Hardness files work well for the most part..  Super handy to have and use.. 

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Are you planning a *nice* shelf in the shop to display such finds?   I'm mounting old "finds" from the scrapyard on the walls of my shop.  Things I can't bear be melted as scrap; but I am not actively "using". Like this old crosscut saw with a large Drafthorse shoe riveted to it as the handle. (My latest was a couple of "spoons" used to remove cuttings from holes drilled in rocks before insertion of "boom stuff".)

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Yes for sure on vintage forged iron.. I have a bunch of items saved up.. I have old buggy seat back, few axles, saw, hoes. and a bunch of other things.. 

Having stuff that shows the layup for people is a great learning tool. 

The buggy seat back is an example of very fine forge work.. Stunning really.. All swaged welds.. Very nice.. 

I'm not sure why it is, but most people think today of the turn of the 1900's as archaic..  The level of metal working was amazing..  While it was not as refined or as elegant from a Manufacturing stand point (modern steel production techniques)  and was a bunch more work (hand work)..   They have produced amazing items for thousands of years. 

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Some of the cranes used for fireplace cooking were very ornate and well done; IIRC there are several shown in "Iron and Brass Implements of the English House".

What's fun is to also have some examples of poorly done work from 100+ years ago. We tend to fixate on the best work; but not every smith was working at that level!

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Good point Thomas.. Depending on the area and crafts person depended a long on the quality of work..  Also generally the type of work they did.  Mine smith, railroad smith, factory hardware smith, etc, etc..  There were smith in nearly every industry.. Hospitals, factories, etc, etc.. 

I've seen some work that makes you wonder what they were thinking but here it is 200 years later still going. 



 

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It's always gotten me when folks ask "Was this made by a smith or was it made in a factory?"    Lots of stuff were made by smiths *in* a factory! (Or a prison for that matter, IIRC Ohio Tool used prison labor. I picked up a book on the history of prison labour in America just for the pictures of their smithing setups. )

Having some exquisite examples of what can be done is an inspiration; but having some "hack jobs" can help some people who are thinking of giving it up because they can't do a masterpiece from the start.   

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I am not a fan of the immediately awesome abilities thought process which seems to pervade today. 

 

I keep all my first items as an example of where i started.

 

Working with someone skilled automatically raises the ability level 20fold.

I say it all the time. I've made hundred of thousands of mistakes and look at this as normal in everything i have ever done.

 

At some point the mistakes fall to the wayside and excellence takes its place.

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The ones that do tend to listen more carefully and advance more rapidly; however there are always the people who need direct experience with the electric fence themselves.  (I'm probably one of the few folks in the USA that have ever gotten caught in an electrified barbwire fence while wearing a chainmail shirt!  Boy that was a long time ago!)

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