JeepHammer
Moderator
This has never been cheaper, although it's not 'Easy'...
The idea is to cut a piece of brass, new in perfect shape from the manufacturer,
From different manufacturers,
And see what the factory is doing to the brass structure for 'Optimum' performance.
You will be surprised at the difference between brass from different manufacturers!
Then cutting & preparing samples of YOUR brass for comparison.
Both fully hard, then annealed to different temperatures & times....
Doing this gives you permanent reference samples.
This will allow you to directly see what you are getting for your efforts compared to what the factory is doing.
You CAN just polish a sample and throw it under magnification, but you won't see much.
Preparation is the key to directly see what's happening.
Now, you aren't preparing samples for NASA or an anal retentive government inspector, so you CAN do this much cheaper with good results!
First off, taking the sample,
You CAN NOT expect good results if you cut, sheer, hammer, chisel, grind (etc.) your sample,
Then look at the damaged area!
DO NOT hammer a rounded case section flat!
Simply mount the outside curve DOWN so you can sample the case section in it's natural state.
You want to COLD CUT the brass sample with as little heat/damage as possible.
If the brass discolors while cutting, you screwed up, not enough coolant.
You want to remove the damaged section far enough back to see the structure where it's NOT been damaged,
Wet saws prevent heat damage, good old hack saws with the highest tooth count as possible, or an abrasive edge.
GO SLOW so you don't heat the sample up, flex the sample (work Hardening when you flex it back & forth).
IF YOU DO BUTCHER THE SAMPLE, all is not lost,
Simply polish a spot away from the damaged area.
If your sample is big enough to get a good grip on, then resin block mounting (scientific standard) isn't necessary.
I often don't bother mounting case head cross sections, they are big enough to handle during polishing, while case side & neck samples are always mounted simply because they are crazy hard to hold onto or keep flat during polishing.
Resin block mounting makes small samples MUCH easier to grind/polish, and is the scientific standard way to handle samples.
Scientific GRADE mounting resin will set you back a pretty penny,
A MUCH cheaper alternative that's stupidly available is resin CRAFTS STORE encapsulation hobby kits.
We are talking anywhere your wife likes to browse for 'Crafts' stuff, from 'Jo Ann' fabrics to Hobby Lobby to Wally-World.
They usually come with a quart or more of the 2 part resin compound, often with little cups or stirring sticks & other goodies, some have mold release included if you want really professional looking samples without polishing all the outside of the sample.
I use flexible silicone candy/cupcake/icecube/soap molds, dirt cheap off eBay or Amazon, available everywhere from Walmart to any hobby shop.
----
Once sample is mounted (your choice of mounting),
Then you polish. This is the part I dislike most.
Using SILICONE CARBIDE (and silicone carbide ONLY!),
I repeat, silicone carbide only!
Aluminum oxide or other types of abrasives can & will mix into your brass sample!
And the WILL screw up your chemical treating & observable results!
Starting at about 180 to 320 grit (Depending on how much you need to 'Hog Off' getting to clean sample material),
Then reducing size of grit to about 1,200 grit WET!
Then finishing off with buffing wheel & polishing compound.
Unless you are completely useless, we have all sanded or polished something,
Same thing only in the extreme.
One tip,
Silicone carbide sanding discs come on rolls, adhesive backed, intended for wet sanding for anything from body shops to wood shops to metal/welding shops.
That gets you 50% the way to an effective wet sander/polished.
Adhesive backed water resistant sanding disks make for fast disk changes, either for a clean disk or finer grit.
The polishing compound should be silicone carbide also, but graded for size (so stray larger granules don't randomly scratch your sample) and suspended in a lubrication of some kind, like lapping compound.
DO NOT let the pad get dry!
-----
Then samples head for chemical etching...
Different chemicals make the chrystaline structure 'POP' and appear different colors under white light.
Again, I'm NOT working for NASA or trying to justify my existence in some government job,
I often use common household or easily available chemicals.
Swimming pool conditioners, toilet bowl cleaners, hydrogen peroxide, white vinegar, even liquor store for 'Everclear' for Ethel alcohol.
Other than taking a little longer than 'Scientific' grade chemicals, you get pretty much the same results.
------
Viewing,
This is where the cost has dropped like a rock!
Just 15 years ago, a 1,000X scientific grade, scaling graduated, stereo microscope started at $22,000.
Now you can buy a USB or blue tooth magnifier for $20 that will work pretty good.
2 mega pixel or higher (usually 2mp or 5mp), in the 200X to 500X range will make you as happy as a pig in a corn crib!
Most micrograph images are in the 200x to 300x range, but for $5 or $10 you can get into 500x to 800x ranges and REALLY see what's happening.
Just get one with a good FLOOR PLATE STAND!
No stand or lousy stand will drive you crazy, so instead of $10 or $20, spend $30 and get more megapixel, magnification and a good stand, or make one immediately!
Now that you can actually directly SEE grain structure, chrystaline structure, occlusions, voids, ect,
Annealing will make a crap ton more sense to you, and you will be able to change your process to get 'Optimum' results.
Just for the record, there simply isn't an 'Easy' or 'Cheap' way to hardness test.
Hardness testing requires a very specific (scientific) application of force under very specific & controlled conditions.
None of that is cheap or easy....
The idea is to cut a piece of brass, new in perfect shape from the manufacturer,
From different manufacturers,
And see what the factory is doing to the brass structure for 'Optimum' performance.
You will be surprised at the difference between brass from different manufacturers!
Then cutting & preparing samples of YOUR brass for comparison.
Both fully hard, then annealed to different temperatures & times....
Doing this gives you permanent reference samples.
This will allow you to directly see what you are getting for your efforts compared to what the factory is doing.
You CAN just polish a sample and throw it under magnification, but you won't see much.
Preparation is the key to directly see what's happening.
Now, you aren't preparing samples for NASA or an anal retentive government inspector, so you CAN do this much cheaper with good results!
First off, taking the sample,
You CAN NOT expect good results if you cut, sheer, hammer, chisel, grind (etc.) your sample,
Then look at the damaged area!
DO NOT hammer a rounded case section flat!
Simply mount the outside curve DOWN so you can sample the case section in it's natural state.
You want to COLD CUT the brass sample with as little heat/damage as possible.
If the brass discolors while cutting, you screwed up, not enough coolant.
You want to remove the damaged section far enough back to see the structure where it's NOT been damaged,
Wet saws prevent heat damage, good old hack saws with the highest tooth count as possible, or an abrasive edge.
GO SLOW so you don't heat the sample up, flex the sample (work Hardening when you flex it back & forth).
IF YOU DO BUTCHER THE SAMPLE, all is not lost,
Simply polish a spot away from the damaged area.
If your sample is big enough to get a good grip on, then resin block mounting (scientific standard) isn't necessary.
I often don't bother mounting case head cross sections, they are big enough to handle during polishing, while case side & neck samples are always mounted simply because they are crazy hard to hold onto or keep flat during polishing.
Resin block mounting makes small samples MUCH easier to grind/polish, and is the scientific standard way to handle samples.
Scientific GRADE mounting resin will set you back a pretty penny,
A MUCH cheaper alternative that's stupidly available is resin CRAFTS STORE encapsulation hobby kits.
We are talking anywhere your wife likes to browse for 'Crafts' stuff, from 'Jo Ann' fabrics to Hobby Lobby to Wally-World.
They usually come with a quart or more of the 2 part resin compound, often with little cups or stirring sticks & other goodies, some have mold release included if you want really professional looking samples without polishing all the outside of the sample.
I use flexible silicone candy/cupcake/icecube/soap molds, dirt cheap off eBay or Amazon, available everywhere from Walmart to any hobby shop.
----
Once sample is mounted (your choice of mounting),
Then you polish. This is the part I dislike most.
Using SILICONE CARBIDE (and silicone carbide ONLY!),
I repeat, silicone carbide only!
Aluminum oxide or other types of abrasives can & will mix into your brass sample!
And the WILL screw up your chemical treating & observable results!
Starting at about 180 to 320 grit (Depending on how much you need to 'Hog Off' getting to clean sample material),
Then reducing size of grit to about 1,200 grit WET!
Then finishing off with buffing wheel & polishing compound.
Unless you are completely useless, we have all sanded or polished something,
Same thing only in the extreme.
One tip,
Silicone carbide sanding discs come on rolls, adhesive backed, intended for wet sanding for anything from body shops to wood shops to metal/welding shops.
That gets you 50% the way to an effective wet sander/polished.
Adhesive backed water resistant sanding disks make for fast disk changes, either for a clean disk or finer grit.
The polishing compound should be silicone carbide also, but graded for size (so stray larger granules don't randomly scratch your sample) and suspended in a lubrication of some kind, like lapping compound.
DO NOT let the pad get dry!
-----
Then samples head for chemical etching...
Different chemicals make the chrystaline structure 'POP' and appear different colors under white light.
Again, I'm NOT working for NASA or trying to justify my existence in some government job,
I often use common household or easily available chemicals.
Swimming pool conditioners, toilet bowl cleaners, hydrogen peroxide, white vinegar, even liquor store for 'Everclear' for Ethel alcohol.
Other than taking a little longer than 'Scientific' grade chemicals, you get pretty much the same results.
------
Viewing,
This is where the cost has dropped like a rock!
Just 15 years ago, a 1,000X scientific grade, scaling graduated, stereo microscope started at $22,000.
Now you can buy a USB or blue tooth magnifier for $20 that will work pretty good.
2 mega pixel or higher (usually 2mp or 5mp), in the 200X to 500X range will make you as happy as a pig in a corn crib!
Most micrograph images are in the 200x to 300x range, but for $5 or $10 you can get into 500x to 800x ranges and REALLY see what's happening.
Just get one with a good FLOOR PLATE STAND!
No stand or lousy stand will drive you crazy, so instead of $10 or $20, spend $30 and get more megapixel, magnification and a good stand, or make one immediately!
Now that you can actually directly SEE grain structure, chrystaline structure, occlusions, voids, ect,
Annealing will make a crap ton more sense to you, and you will be able to change your process to get 'Optimum' results.
Just for the record, there simply isn't an 'Easy' or 'Cheap' way to hardness test.
Hardness testing requires a very specific (scientific) application of force under very specific & controlled conditions.
None of that is cheap or easy....
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