Hardness tester

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SmithDoor

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Simple hardness for material hunting.
Leave no marks

This is Simple a stick 12inchs long or 300 mm like paint stick.
And a copy of page wrap around stick for marks. .

Hardness Tester.jpeg


I have bag if 3/8 hardened balls. So if loss one anc more to use.

I have different one for shop use a 3/16" balls for thiner gauge.

UPDATE Feb 26 2025
Use 3/16" or 3mm ball bearing BALL and a zero was add foe metric 3cm to 30 cm


Dave
 

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I have seen one backyard casting person obtain a ball-type hardness tester, and he seems to get accurate results with it, as far as testing his iron castings for chills and hard spots.

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I have seen one backyard casting person obtain a ball-type hardness tester, and he seems to get accurate results with it, as far as testing his iron castings for chills and hard spots.

.
I had check class 45 cast iron and would not fit in Rockwell tester.
Rutland had a unit for none destruction testing I purchased and very simple . A 3/16 ball from ball bearings. And a clear tube . It work but easy to lose the small ball so I up size so easier to find the ball. Then used a paint stick good and bad marks . Now my crew could check the hardness too. They set wheel on floor and drop ball. In time a rug around the wheel stop ball from hiding . The pickup ball and check next wheel. We did not check every wheel just in in each batch.
Then when looking materials it came handy too.

Dave

FYI I still have the test disk from Rockwell hardness test I think last for ever
 
Do you have to use a 9.5 mm ball with the metric version ? <big evil grin> Thinking of the metric adjustable wrench cluster :cool:

Actually quite a neat way to get low cost hardness testing into our world, thanks for posting this! I'd seen the vacuum column ball drop style in the past but not the linear scales to make it so easy.
 
Do you have to use a 9.5 mm ball with the metric version ? <big evil grin> Thinking of the metric adjustable wrench cluster :cool:

Actually quite a neat way to get low cost hardness testing into our world, thanks for posting this! I'd seen the vacuum column ball drop style in the past but not the linear scales to make it so easy.
The only time I found was a small ball work best on thin material.

The larger size is easier to find on floor.

3.5 mm will work great the only other requirement is ball bearing hard. A soft ball has smaller bound.
The ball bearing hard ball has a uniform bound.

For me it was surprising how accurate the boun is for hardness.

I no longer need a Rockwell hardness testerand a good machinist doing testing.
In most cases a welder or helper could use a paint stick with 2 marks and ball.

For me it is so simple and accurate tool in my chest. This something everyone can have in chest.

Dave
 
FYI
The paint stick work best with a pisce of wood glue at 9½" so roll ball for drop. At that point only need a mark . If ball boun over the mark it is good .

Should made clearer one mark was for the release of ball. I did think about round bubble level as some hard hard time keeping stick plumb

Dave
 
Hi Dave,

Looking at your drawings I do wonder if you have missed out a "0" ! Right at the top where you have put 3cm is 30 mm, should that not be 30 cm.

When I get my hands on a suitable perspex tube I will build one ! It should be very useful when hardening material.
 
Hi Dave,

Looking at your drawings I do wonder if you have missed out a "0" ! Right at the top where you have put 3cm is 30 mm, should that not be 30 cm.

When I get my hands on a suitable perspex tube I will build one ! It should be very useful when hardening material.
You could use clear tubing and a angle iron to hold it straight or plexiglass sheet from Home Depot or Lowes and a make a long box . The tube is only for not losing the ball.

Dave
 
Hi Dave,

Looking at your drawings I do wonder if you have missed out a "0" ! Right at the top where you have put 3cm is 30 mm, should that not be 30 cm.

When I get my hands on a suitable perspex tube I will build one ! It should be very useful when hardening material.

Here my first ball drop hardness tester still have first ball.


20250225_185139.jpg


If look close you can marks for different hardness on ½ plate
20250225_185130.jpg


Spare bag of ball bearing just in case . Never open.

20250225_185314.jpg


Rockwell hardness test disk.

20250225_185220.jpg


I also have ⅜" ball bearing balls used for paint stick and employees to use.

Dave
 
Sorry if this has been discussed before, but here is a design for (I think) similar tester principle using Arduino. This may or may not be one of the original build links.

https://www.hobby-machinist.com/threads/how-to-make-your-own-hardness-tester.112111/
It is interesting.

One could use at bottom a switch/photocell that turns on a photocella in rest of tube and records the high point of bound.

Then a reset button for next test.

This how would work

Start 1)
⚽ Ball ready for drop










❋ trig switch photocell


2) Photocell triger switch
Ball drop











⚽ trues on above photocell



3) Highest point of bounds record by trunk on the LED



⚽ Highest point of bouns





 
I tried similar things. I found a cheap Leeb type hardness tester on eBay that was electronic and has a calibration disk for an affordable price. It is easy to use and gives the results immediately.

Should you be interested I can get the information for a Web search.

Cheers,
Andrew in Melbourne
 
Interesting and simple to let a ball drop in a tube and measure the rebound. I guess you can bring the ball to a correct height by using a magnet on the outside.
I like the idea 💡 sound great

I do not remember why not to a magnic but will be reading off.
It in paper work I received with test no magnic and if ball becomes magnictized use a degaussing machine. Remember I read paper work in the 1970’s I only have chart today.

Thank your idea 💡
Building would real simple.
 
Interesting and simple to let a ball drop in a tube and measure the rebound. I guess you can bring the ball to a correct height by using a magnet on the outside.
Here chart from 1970’s
Also a pdf copy
HardnessTesterChart.jpeg
 

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  • CCI_0001(2).pdf
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