Induction annealing question

[Gina1]

Hi Guys

When doing induction annealing, how far down do you anneal ?
Using Tempilaq, and painting the whole case, the longer the case is in the induction coil, the further down the Tempilaq changes color. Do you just do the neck, or do you take is a short way past the shoulders ?
Looking for opinions.

Much thanks

Gina

 

[gotcha]

Hi Guys

When doing induction annealing, how far down do you anneal ?
Using Tempilaq, and painting the whole case, the longer the case is in the induction coil, the further down the Tempilaq changes color. Do you just do the neck, or do you take is a short way past the shoulders ?
Looking for opinions.

Much thanks

Gina

Same as doing propane annealing. Use 750 degree tempilac and anneal to slightly below the shoulder. For added indications you can put a dab of 750 degree tempilac inside the neck to insure you have enough duration time to effect an anneal through and through........ If you're new to annealing I'd suggest also using a 450 degree Tempilac stripe on the case body ( annealing starts @ about 482 degrees) to insure you don't soften the case head.............. Use throw away brass 'til you get the hang of it. Have fun!

 

[Gina1]

Gotcha...

Thanks for the info. Am using 750 degree Tampilaq. Just wanted to make sure I'm doing it right.

Gina

 

[muleystalker]

Gotcha...

Thanks for the info. Am using 750 degree Tampilaq. Just wanted to make sure I'm doing it right.

Gina

What annealer are you using?

 

[Hollywood]

She is using one of these. Different enclosure. Somthing we have been in cahoots together building.

 

[Webster]

Same as doing propane annealing. Use 750 degree tempilac and anneal to slightly below the shoulder. For added indications you can put a dab of 750 degree tempilac inside the neck to insure you have enough duration time to effect an anneal through and through........ If you're new to annealing I'd suggest also using a 450 degree Tempilac stripe on the case body ( annealing starts @ about 482 degrees) to insure you don't soften the case head.............. Use throw away brass 'til you get the hang of it. Have fun!

The low end of annealing temp is 750-800F not 482F.

 

[gotcha]

The low end of annealing temp is 750-800F not 482F.

Webster, Please refer to { the art and science of annealing } in the "articles" section......... Grain structure begins to change @ 482* F. ...... Below that temp. no annealing takes place no matter how long a time period. To clarify, I was suggesting using a 450* F Tempilac stripe on the case body to monitor how far down the case annealing would actually take place so as not to soften the case head....... Tempilac doesn't make a 482* F indicator so the 450* F provides a good educated guess. Helpful on really short cases like 6 BR or 300BO.

 

[Hollywood]

Does the annealing actually need to go below the shoulder or is right at the shoulder a more ideal spot to stop if it were controllable to that point. When you bump the shoudler back aren't you just moving the angled portion of the case and not disturbing the side walls.

Is it that the current methods are not capable of controlling the annealing that precisley? Or is slightly below the shoulder actually desired?

This is a progression of time duration to amount down the case annealing occurs. 750* tempilaq

 

[deepwater]

Hollywood,

Please comment on the construction/components of your induction annealer.

Thanks,

deepwater

 

[Hollywood]

Hollywood,

Please comment on the construction/components of your induction annealer.

Thanks,

deepwater

I and Gina1 have developed this machine. The idea of it was mine and Gina1 helped with design of the trap door assembly and the finer design points with her background in electrical engineering.

The basics of it are a 48v power supply, 4 mode timer with adjustment down to .01 second, induction board, custom made coil assembly, pc radiator, pc fan, 12v water pump, custom made trap door assembly.

I have one up and running but finalizing some of the design aspects before I fully put it out for the public to see. Gina1 also has an earlier "prototype" version of it running.

 

[itchyTF]

Hollywood,

Sounds like you stole my design!! Except mine is powered by 120Vac.
Mine is also water cooled, has a trap door and has 10 ms resolution.

 

[Hollywood]

Hollywood,

Sounds like you stole my design!! Except mine is powered by 120Vac.
Mine is also water cooled, has a trap door and has 10 ms resolution.

Great minds think alike!

Here is a quick video. Hopefully the link works. Never uploaded a youtube video or posted a link to one for that matter.

 

[Webster]

Same as doing propane annealing. Use 750 degree tempilac and anneal to slightly below the shoulder. For added indications you can put a dab of 750 degree tempilac inside the neck to insure you have enough duration time to effect an anneal through and through........ If you're new to annealing I'd suggest also using a 450 degree Tempilac stripe on the case body ( annealing starts @ about 482 degrees) to insure you don't soften the case head.............. Use throw away brass 'til you get the hang of it. Have fun!

I don't care what Ken Light says it's wrong. There are ten's of accurate sources that state stress relieving and annealing temperatures. 482F is in slightly below the stress relieving temp range not the annealing range.


Data from sellers of copper and brass sheet, plate and wire.

Source: http://www.totalmateria.com/Article25.htm

Stress Relieving (not annealing)

Stress relieving is aimed to reduce or eliminate residual stress, thereby reducing the likelihood that the part will fail by cracking or corrosion fatigue in service. Parts are stress-relieved at temperatures below the normal annealing range that do not cause recrystallization and consequent softening of the metal.

Residual stresses contribute to this type of failure, which is frequently seen in brasses containing 15% zinc or more. Even higher-copper alloys such as aluminum bronzes and silicon bronzes may crack under critical combinations of stress and specific corroding, and all copper alloys are susceptible to more rapid corrosion attack when in the stressed condition.

Stressed phosphor bronzes and copper nickels have comparatively slight tendencies toward stress-corrosion cracking; these alloys are more susceptible to fire cracking, which is cracking caused when stressed metal is heated too rapidly to the annealing temperature. Slow heating provides a measure of stress relief and minimizes non-uniform temperature distributions, which lead to thermal stress.

Using a high stress-relieving temperature for a short time is generally considered best for keeping processing time and cost to a practical minimum, even though there is usually some sacrifice in mechanical properties. Using a lower temperature for a longer time will provide complete stress relief with no decrease in mechanical properties. Actually, the hardness and strength of severely cold worked alloys will increase slightly when low stress-relieving temperatures are used.


SOURCE: http://www.lfa-wire.com/70-30-brass-wire_c26000.htm

PHYSICAL PROPERTIES
C26000, 70/30 BRASS
Annealing Temperature
800-1400°F
425-750°C

Stress Relief Temperature
(1 hr)
500°F
260°C

 

[Hollywood]

I don't care what Ken Light says it's wrong. There are ten's of accurate sources that state stress relieving and annealing temperatures. 482F is in slightly below the stress relieving temp range not the annealing range.


Data from sellers of copper and brass sheet, plate and wire.

Source: http://www.totalmateria.com/Article25.htm

Stress Relieving (not annealing)

Stress relieving is aimed to reduce or eliminate residual stress, thereby reducing the likelihood that the part will fail by cracking or corrosion fatigue in service. Parts are stress-relieved at temperatures below the normal annealing range that do not cause recrystallization and consequent softening of the metal.

Residual stresses contribute to this type of failure, which is frequently seen in brasses containing 15% zinc or more. Even higher-copper alloys such as aluminum bronzes and silicon bronzes may crack under critical combinations of stress and specific corroding, and all copper alloys are susceptible to more rapid corrosion attack when in the stressed condition.

Stressed phosphor bronzes and copper nickels have comparatively slight tendencies toward stress-corrosion cracking; these alloys are more susceptible to fire cracking, which is cracking caused when stressed metal is heated too rapidly to the annealing temperature. Slow heating provides a measure of stress relief and minimizes non-uniform temperature distributions, which lead to thermal stress.

Using a high stress-relieving temperature for a short time is generally considered best for keeping processing time and cost to a practical minimum, even though there is usually some sacrifice in mechanical properties. Using a lower temperature for a longer time will provide complete stress relief with no decrease in mechanical properties. Actually, the hardness and strength of severely cold worked alloys will increase slightly when low stress-relieving temperatures are used.


SOURCE: http://www.lfa-wire.com/70-30-brass-wire_c26000.htm

PHYSICAL PROPERTIES
C26000, 70/30 BRASS
Annealing Temperature
800-1400°F
425-750°C

Stress Relief Temperature
(1 hr)
500°F
260°C

They don't call you Webster for nothing do they. What's you thought on annealing just to the junction of the case body and shoulder?

 

[gotcha]

Does the annealing actually need to go below the shoulder or is right at the shoulder a more ideal spot to stop if it were controllable to that point. When you bump the shoudler back aren't you just moving the angled portion of the case and not disturbing the side walls.

Is it that the current methods are not capable of controlling the annealing that precisley? Or is slightly below the shoulder actually desired?
View attachment 975601
This is a progression of time duration to amount down the case annealing occurs. 750* tempilaq

Tempilac is designed to be used on the side opposite of the flame and will become clear when annealing temp is reached (inside the neck). Using Tempilac on the outside of the case causes the tempilac to turn black. It appears you could use more time or a higher temp........ Yes, I like the color change to stop about 1/8" to 3/16" below the shoulder/ body junction to insure entire shoulder is annealed for uniform bump......... Is your pic showing shortest time on right ?? Induction or gas ??

 

[Hollywood]

Tempilac is designed to be used on the side opposite of the flame and will become clear when annealing temp is reached (inside the neck). Using Tempilac on the outside of the case causes the tempilac to turn black. It appears you could use more time or a higher temp........ Yes, I like the color change to stop about 1/8" to 3/16" below the shoulder/ body junction to insure entire shoulder is annealed for uniform bump......... Is your pic showing shortest time on right ?? Induction or gas ??

Shortest on right and it's induction.

 

[Webster]

They don't call you Webster for nothing do they. What's you thought on annealing just to the junction of the case body and shoulder?

Of course Webster isn't my real name. It's the name I used when ordering pizza.

The neck must get a little hotter the the shoulder because it's smaller and thinner. I still think you can't go wrong if you determine how long it takes the neck to get slightly red in a dark room and give it about 2 seconds less time. This should come about as close as you can to a factory anneal. If you anneal this way I would assume the shoulder is fine. Going longer to try to do something on the shoulder would over heat the neck. I don't have a shoulder bump gauge but guys that have them report they get the bump they want with a simple anneal. It isn't possible for the body below the shoulder or the head to get softer. It's real simple I don't know why so may people keep asking the same questions.

Look up the post on how long does it take to ruin a case.

Posted on Page 11
How long does it take to dangerously anneal a case.
Posted 19 Jan 2016 by furmaster

Single flame torch

From the post.
650F templaq (not 750F)
7 sec to melt inside neck
16 sec till the neck was red (I get the neck red in the 11-12 sec range)
38-58 sec to melt the templaq in the belt /head area.

 

[Hollywood]

Thanks Webster.

 

[gotcha]

They don't call you Webster for nothing do they. What's you thought on annealing just to the junction of the case body and shoulder?

Well, you know the old saying. " If you can't dazzle them with your foot work, baffle them with BS". ............... We're talking about selectively annealing a portion of a case in a home environment. Not oven annealing in a chemically controlled atmosphere environment in a factory designed specifically for industrial level annealing.................. Thus Ken Light's practical approach to the basics of annealing cartridge cases without the benefits of the above. Ken's methods ain't rocket science but produce excellent results as proven by the numerous manufacturers making annealing equipment and using his basic principles. .................. I rest my case ( pun intended)

 

[gotcha]

Shortest on right and it's induction.

That's what I was thinking..... I haven't had the occasion to use induction annealing yet. ........ Since Tempilac may give different visual results (coloration) with induction as opposed to gas it seems appropriate that an induction annealer guy might have a more accurate opinion than mine............. With gas, I center my flame just below the neck/shoulder junction to insure not overheating the neck yet get full anneal on the thicker shoulder. It could be that a little more testing with your induction unit might be the way to go for that "just right" anneal. JMHO