Rockwell testers???

NickWheeler

NickWheeler

Joined
Dec 3, 1999
Messages
9,437
I'm planning on getting a Rockwell tester. I've been taking my blades and test tiles to a "local" machine shop (30 miles away) and they'll test for $2 a pop. That's cheap, but it's a PIMA.

I have so many tests I want to run, that I'd really like to have one here in my shop.

I remember an article by Phil Wilson several years ago in which he compared a Chinese import against his Wilson tester (the irony, I know ;) ).

I have been looking at Wilson testers on ebay, but I wonder if I wouldn't just be better off with an import. You can get a brand-new import from Enco for about $800.

Anybody have any thoughts and input on this???

THANKS!!!
-Nick-

http://www.wheelerknives.com
 
nick..........I got mine from Grizzley and I would recomend it big time.! Works great..........
 
NickWheeler said:
they'll test for $2 a pop. a brand-new import from Enco for about $800....

Anybody have any thoughts and input on this???
Click to expand...

Well , my thoughts are that you have a great wife,
or are yourself a darn good salesman ,
if you sold her on the idea that getting something for $800 is better than spending $2 bucks now and then for a test.....
 
HAHAHA! :D

Still not married... so no asking for permission... yet. ;) :D

I should have expounded on that a bit. It's $2/test, but I have already gone in there and had about 150 tests done over the last couple years. Factor in the time and gas money to get there, and I'm already over half-way to buying a damn tester :eek: :)

With my work schedule (now having a "real" job and not a stay-at-home-bladesmith anymore) it's nearly impossible for me to get into that machine shop before it even closes for the day. So that option is not so viable anymore anyway.

It really comes down to convenience.

AND the fact that I'm still young, NOT married, making good money now and buying all the "toys" that I could not afford as a bladesmith. :cool: :D

BTW- I will apologize as I did a new search and found several interesting threads including a lot of information from Phil himself, one of the kings of Rc testing in knifemaking.

I know many folks feel Rockwell value has little to do with a knife's cutting abililty. And I would agree that it is but one of MANY variables in a knife's overall performance. However, I believe it is a good standard to which you can use to get CONSISTANT results in your shop.

Thanks for the heads up Brian! I need to find out if Enco's "free internet purchase shipping" will apply to an order of heat-treat foil and a tester.

Thanks guys!
-Nick-

http://www.wheelerknives.com
 
well, the guys who make and sell the hardness testers have to earn a living too...so why not get one?

But, well, what on earth do you need to do such a high amount of testing for?

From what I have read on this forum is :, Get the best advice from the experts , and if you keep close to what they say, that this will get you in the ballpark as far as expected hardness goes...

Unless you are doing some weird experiments?
LOL
 
Nick,
I was looking at Testers a while back and I got word the Kit that his is th eexact 800 dollar type and has served him well for years.
So I saved money and got the enco type before there hard to get and these days, better safe than sorry is my motto with cheap tools replacing decent ones these days!

PS - I had to go pick mine up at the shiping yard and you better have a friend help. Even a guy your size doesnt need to pull his back out getting this tool single handly!
 
For what it is worth, I have a Chinese model, but I also keep the best test blocks I can on hand at all times. If the machine is adjustable enough, those test blocks are the most important part of the equation. As long as the readings are consistent, you can zero them in with the test blocks. I have encountered some issues with heavy temperature fluctuations in my shop but I think that would be a problem regardless of the machine.
 
I got an Ames portable hardness tester a little while ago. I had never heard of them until my friend Brian Fellhoelter who's a part time knife maker and full time tool and die guy showed me his. These things are cool as hell! I'd been wanting a tester for some time, but between the expense, and the bench space one would take up, I could never get around to buying one. The Ames tester looks like a C clamp with a handle sticking off to the side. Mine came in a fitted case about the size of a cigar box, so it takes up enarly no room in my shop, which is a big plus for me. They're pretty pricy at a little over $2K! I bought mine on ebay. They seem to run between $400.00 - $500.00 on the used market, but if you're patient, you can find a deal. I found one in great shape with both a daimond and a ball penetrator, including Rockwell B and C test blocks in a nice wooden case. I paid significantly less than normal used pricing :) The C scale test block is certified at RC61 so I've got a standard that's right near my target range. I'd rather have the Ames for $400.00 than one of the big bench top machines due to my space limitations. It seems about perfect for a knifemaker. If you buy one on ebay, make sure you don't buy the S model as it's not appropriate to the type of testing we do.

You can see new ones here:

http://www.amesportablehardnesstesters.com/
 
Nick,
I have a HR-150A made in China. This tester receved many international
awards. The knock off is made in Taiwan...lol :D Oh the irony of it all!
You can get one of these for around $700 and it's a very accurate machine and much simpler than Than the Wilson JR-3 models....also third the cost.
I found mine in a pawn shop! for $200:D
 
Nick, I think the offshore machines are fine. The one I had experience with was very consistent. The test block provided read 2 pts different, as I recall, compared to the certified block I got from Wilson. It has already been stated that this is the most important aspect. I use my test block every time I do a series of readings. The machines will drift off calibration due to temp and a lot of other factors. I am working up a list of what I have found over the years will give a bad reading. I will post and maybe others can add to the list. PHIL
 
Nick, Grizzly carries the Chinese model; the same as Enco, et al. If you want to drive to Bellingham, you can pick it up at their warehouse. It might save you some on shipping, depending upon where you are located.

ETA: I started a thread about this a couple of years ago. Kevin included some excellent instructions for calibrating the Chinese models.
 
If you have an MSC account, you can contact your rep and request that they put you in contact with a company that will make you a VERY accurate, certified test block. Mine is certified to within .1 pt Rc! I might have paid about $100 or even $120 or so for it, but, it is absolutely Rc60.

You can go in and polish up the contact areas and make adjustments so that nothing rubs inside. Add some good lube and you're all set.

The trick is learning where to have the needle stop before you throw the lever.
 
Kevin, here is a list of things that will give bad readings, most are obvious but maybe will help some one just starting to use one of these machines. Maybe others will add to the list.


A list of things that can give erroneous hardness testing results

If the spot measured is not absolutely flat it will flex as the stylus penetrates the steel. This spring effect will act with or against the weight giving a false reading.

The measured surface has to be clear of corrosion and scale. It should be at least a surface ground finish. I have found that it is necessary to take off at least 0.002 per side to get a good true reading. My test block is +/- .4 pts and it has a polished finish. So for the same kind of accuracy in theory you would need the same finish.

Any oil or dirt under the anvil will compress and give a bad reading.

Reading on an angle or taper will give a false reading because one side of the stylus will be exposed resulting in less resistance to penetration. This uneven loading can cause breakage of the diamond stylus and it is worth about $200 to replace it.

If the stylus is chipped it will not penetrate evenly.

Temperature changes cause different viscosity in the oil damper on the testing machine resulting in different loading rates with the stylus. Faster loading will give a lower reading. It is best to keep the instrument in an area where the temperature is fairly constant.
 
I had some calibration information that included some guidelines on the rate of load applied, like how many seconds it should take for the major load to bottom out. I cannot locate it now, does anybody have information on this?
 
in Bofors handbook: Heat treating steel. under "rockwelltest" im reading:

first a preload is applied (F0) then you zero the clock (well the measuring instrument) then add another load (F1) for 5-10seconds. after you remove the extra load (going back to the preload) you should be able to get a reading on the instrument. the hardness is a function of the increased impressiondepth which occurs when adding and removing the extra load.

im not sure we are talking about the same type of machine though :confused:

rockwell C:

uses diamondcone 120° radius 0.2mm. first load 10kp (1kp=9.81newton, 1kpm=7.233footpounds). zero the clock. go up to a total of 150kp then back to 10kp. for 1hrc harder the impressiondepth should be -0.002mm. you should do at least 3 impressions and disregard the first one (the first one is inaccurate). the impressions should not be closer than 2mm from each other and at least 3mm from any edge

before every test the machine should be calibrated with a material of known hardness. the reference material should be as close as possible in hardness to the steel you are testing. if the machine is not used very often only the readings after impression number 3 will be accurate
 
M. Wadel, Yes we are talking about the same machine and same process. Thats good info about discarding the first reading, is good practice. Also about making sure the readings are separated. I will add them both to the list. When my machine is cold like 50 F it reads about 1 pt lower than if it was at 70F. PHIL
 
it says the first reading could be affected by dirt, moisture and other things that may have been missed when cleaning the machine, or may have got stuck on the steel somehow. however these will be compressed by the first impression so after that you wont have to worry about them.

usually in machine shops and similar places i know they only measure parts when they are 20°C (usually in special rooms that are adjusted to this temperature) because all the measuring equipment is calibrated to this temperature. could be the same with these too, who knows. i think the most important thing is that you have the same temperature every time to get results you can compare
 
Nick, If you keep your eye open on fleabay you might find a good deal. I picked up a very nice Louis Small 8SSA hardness tester on ebay last year for about half of what that import lists for. I really lucked out because the seller was only about 40 minutes from my house, so I didn't even have to pay for shipping.

LouisSmallTester5.jpg

There are some right now on eBay that you might be interested in ( in no particular order):

WILSON/ROCKWELL HARDNESS TESTER MODEL 5DR 8 RB (Buy-it-now price of $600)

ROCKWELL TYPE HARDNESS TESTER NEW IN BOX (currently $695 + $150 shipping)

FIE Hardness Tester - Model R (Currently $499.98 + shipping. This one is only about 20 miles from my house, so if it interests you and I can be of assistance, just let me know.)

Rockwell wilson hardness tester 3jr nice unit (Buy-it-now price of $800 + shipping. Doesn't seem to say what scales it tests on.)
 
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