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I would say your annealing is failing because the part is so small that it cools too quickly, even in free air. Place it on a piece of 1/8" or 3/16" steel plate and heat it from the underside. once the plate and spring are the correct color put a cap over it and let it cool over several minutes. You can heat it the same way for tempering and push it off the edge as you mentioned. You can even draw it back the same way, carefully!! The plate just gives you much better control of the heating and cooling for such small parts.
 
Thanks for all the responses so far! I have a love/hate relationship with forums. Half the time I hate them because half the time I discover a solution myself 2 seconds after I upload a thread………. The other half is great having other minds to bounce ideas off of. Still other times it is always humbling to be reminded how stupid you can be.:) Twenty years ago I would have just ground the gun up. Retired now, so I no longer have the creeping need to complete the task NOW, because I had other things to do. Back to the thread.

MATERIAL
More than one person mentioned different types of material + flat and round as possibilities. With the limited space were the spring goes, flat is the only shape the will keep the spring in place and under tension.
Also, several people have mentioned different materials for the spring. I have purchased this specific tempered blue spring steel from a reputable dealer (Not cheap) to avoid the issues with unknown types of spring steel. So I don't see how that could be the issue, unless I am missing something.

90 DEGREE BENDS
I have to work by myself, so I guess I will machine a jig for the 90 degree bends. I thought about that early on, but like most proper ideas, sure seemed like a lot of work for one spring. I will sit and think about making a jig that can hold different size pieces of spring material, with an open area where the spring will bend so that heat can be applied and I can immediately make the bend with just 2 hands……. We shall see.
The odd part is that both billdeserthills & ZigZagZeke mentioned annealing the steel first. I have always done that, and it seemed to work. But, for some reason with this very-very thin spring steel it does not seem to anneal properly. I anneal, bend, and it snaps. Even doing the gentle rounded bend, not just the sharp 90 degree bend. Is there a different amount/length of heating required to anneal this thin a piece of steel? I really need some additional feedback on this part. Any ideas?
I understand P7M13's ideas, but I am not sure a kiln would even work. It is strange. The metal is so thin a .017" thickness, if I heat to red and immediately touch it with anything (like pliers), that area immediately goes from red to dull because of the heat sink occurring form the tool. I have tried to heat the tool also (To below red) so that it is not 'cold', but that does not seem to help. Why? Again, I have done this making other springs and never had this difficulty????

HEATING & QUENCHING
For the Heating a quenching step I think I will get a fire brick and set the spring on its side, on the edge of the brick. Then at temperature I can quickly just push the spring over the edge of the brick and into the waiting oil. I can see that should be sufficient.
A follow up question. Is there a different temperature needed for very-very small material, than for normal thicker springs? I only say this because I most often successfully create a normal sized spring on the first or second try. After 6 or 7 tries on this one, still no success.

I will move forward on these ideas and see what happens. Just not comfortable that the issues are solved yet…………….
The smaller the work piece the harder it is to control the temperature. I think you need a kiln/oven instead of a torch to do what you want to do. With the torch I think you are overheating or underheating your work piece. Also, you are probably not getting any surface effect, where the surface layers are harder or softer than the interior of the piece. This kind of stratification is essential in some cases.
 
While I never give up on a project, so far I am unable to successfully make this spring. I have applied ALL the techniques and suggestions given here. I just broke my 18th spring this morning. No amount of change or tweaking to the process seems to solve the issue. Upon application, the spring breaks. The issue remains: What makes a spring break? Obviously, it must be too brittle. Why? I can only think of two possible remedies.

1) How technically, do I make the spring less brittle?
(If the tempering process is the sole step that determines brittleness, I must need to do it differently. How? Higher temperature tempering? Lower temperature tempering? Longer tempering? Current tempering is done at 615 degrees for about 1 or 2 minutes.)

2) Is the base spring steel I am using bad in some way?
(I guess I could obtain some other spring steel & try it. Problem is that when you are looking at a spring steel that needs to be only .017" thick, there are not a lot of places to obtain that thickness. I tried earlier making the same spring out of .023" thick material. It had sufficient movement in the gun & did not break, but was so stiff, as to make the function of cocking the hammer almost impossible.....)

Really frustrated!
 
**SOLVED**
Finally! I hate leaving a thread hanging without a solution (If any) that resolved the issue. The critical three words in this thread are "very small spring". Here is how I worked through the problem.

ISSUE:
The "Very small spring" I would create, continually would break during testing or function. Spring size is: .015" D x .070" W x .700" L. Spring was too brittle!
I cannot stress enough how important these steps are in creating a "very small spring". I believe I will incorporate some of this method into my creating larger springs also. But it is imperative that these or similar steps be used for the smallest of springs.

What I Was Doing Wrong:
1) Started with already tempered .015" spring steel. I learned that 1095 steel, which is what most spring steel is made from, is not designed to be annealed, once it has been hardened & tempered. (Yes, I know it can be done successfully. I have even done it myself. But always on larger springs. Smaller springs are less successful.)
2) Trying to hold onto the "very small spring" while heating a quenching cased too much of a heat sink and caused uneven heating before quenching.
3) Removing the "very small spring" from the tempering treatment into room temperature did not allow the tempered spring to cool slowly. Rather the spring was shocked by the quick reduction of temperature and did not fully retain the tempering.

Solution:
Here is a step-by-step of how I finally successfully created this "very small spring". I am sure this is not the only method, but it worked on my size spring with my equipment.
  • Purchased annealed from the factory 1095 spring steel in .015" thickness. (From McMaster-Carr a 3" x 3" sheet with shipping was less than $20.)
  • Cut the flat annealed spring to just over dimensions of .015" D x .070" W x .700" L
  • Filed & sanded to size, then polished the external surfaces of the spring
  • The factory annealed 1095 was a pleasure to bend & form to shape. Very easy.
  • Laid the formed spring on top of a couple of firebrick. Sat a container of oil just beside the bricks.
  • Used MAPP gas to slowly bring the spring to cherry red. Held the color in the spring for about 1 minute.
  • Immediately brushed the cherry red spring into the oil.
  • After removing from the oil, used emery paper to clean off the carbon. Careful not to bend the brittle spring.
  • Heated my lead pot to 625° (Digital Thermometer checked)
  • Placed a small piece of regular 1018 steel on top of the melted lead, to one side. (2"x1"x.150")
  • Waited for the piece of floating steel reach temperature. (It became a beautiful blue by-the-way)
  • Dropped the spring on top of the melted lead. After 5 minutes flipped the spring over on the lead.
  • After another 5 minutes, placed the spring on top of the larger piece of steel. (Which puts the spring out of the lead but still on something the same temperature as the lead)
  • Immediately place a firebrick on top of the lead pot to help hold in the heat.
  • Turned off the lead pot & let set several hours until cool.
  • Once cool, removed the spring from on top of the large piece of steel. (Next time I heat the lead I can remove the flat piece of steel)
  • Tested. Installed and re-tested. All good! See image below.
I was told heating the lead to 850°-900°, then leaving the spring in the lead pot until cool would also work for annealing already tempered spring steel. If it worked for this "very small spring", then I would not have to buy already annealed spring steel in the future. Will try this at some point.

I also learned of another option. Using 1075 spring steel. 1075 is more accommodating for annealing already tempered spring steel.

Here is some additional information about these 2 SAE spring steels:

From Admiral Steel
SAE/AISI 1095 Cold Rolled Spheroidized Annealed = Deep Blue Finish When Tempered
Annealed 1095 has the highest elastic limit and fatigue values of the commonly used spring steels. For high quality intricate shapes that cannot be formed from pre-tempered steel. Used where SAE hardening and tempering after forming is desired, but fatigue values and elastic limits are not critical. This type of annealed spring steel adaptable for forming with good hardening qualities.
Not designed to be annealed and formed once it has been blue tempered………….

From McMaster-Carr
1095, These sheets have a softened temper, which is also known as annealed, so they can be easily formed into shape and then heat treated for spring properties. 1095 spring steel has a higher carbon content than 1075 spring steel for better wear resistance. It is often fabricated into parts that will be used under continual stress, such as spring clips and washers.

From Admiral Steel
SAE/AISI 1074/1075 Cold Rolled Spheroidized Annealed = Dull Blue/Grey Finish When Tempered
Annealed 1075 (.010"-.032") General purpose medium carbon grade of cold rolled annealed spring steels. It has toughness & elasticity adaptable for difficult forming and will provide excellent results in the hardened & tempered condition. This is a top quality, killed, fine grain (#5 or finer) material that is rolled to the closest possible gauge tolerances.
Can be annealed from blue tempered, shaped, then re-blue tempered…………

From McMaster-Carr
1075 spring steel is easier to bend than 1095, but it has less bounce-back after heat treating. It is often used for springs and shims. This material is also known as scaleless steel.
 

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I'd bend the 90s first. Place the stock in a small vise or locking plyers, exposing only the part your wanting to bend. Heat and then hammer the exposed part to create your 90°. Use some piano wire tied to the spring for the quench. The wire can withstand the heat and will be thin enough to not act as a great sink. Best of luck!
 

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