Annealing: Settled on a method with highest repeatability - using garage tools

[zambezi]

A while back I invested some time in building a Skippy-style annealer. As with all projects, the journey is half the fun. But what I soon realised was that the annealer I could make was not going to give AMP performance. And it would be a faff to operate.

So...what I have done instead is perfect the method by which I anneal using a cordless drill cupping the case head in a ratchet socket of appropriate dimensions . I am 100% sure that this method gives repeatable results.



What makes this method accurate is a multi-way check using several methods found on SD and YT. Vitally important: perform annealing in a darkened room. The iridescence of the brass is subtle and best viewed in black out. Second discovery: if your burner is too cool, the whole case gets heated by the time the neck is ready. Better to run a hot flame and have lightning responses to the colour change described below.

1. I used Alan's soap test to verify that the neck had reached annealing temperature whilst being rotated in flame. Repeat tests showed that soap threshold is reached when...
2. ...inside neck colour switches from black to black-red . There can be no lingering in the flame past that point because test runs reveal that in just 2 secs more colour changes to...
3. ...candy-apple red and that spreads down the shoulders in sub 1 sec thereafter at which point...
4. ...removing the case from the socket with bare fingers is uncomfortable. Burnt fingers/hot socket means the brass was heated too long. Uniformity of finished product confirms method

 

[Klenchblaize]

I have to say I think you've annailed it!

Enjoy your increased case life - read cost saving - and consistency of neck tension.

K

 

[andyk]

Good demo and similar to what I’ve been doing. One thing I’ve found helps is if you have one of those cheapo trimmers from Lee, as they come with an attachment which fits into a cordless and securely holds the case head.

 

[ChesterP]

That's exactly what I used to do before getting a "Raptor Calls" annealer which I now use with propane and a gas torch affixed to the annealer bracket. I set each case type up an a darkened room and when the inside of the neck at the very top just starts to glow a dull red, that's the time set. Usually this results in an annealing rainbow just below the shoulder of the case, but not always. Initially I was told I needed a £20 little bottle of tempilaq but all that seemed to do is to confirm that my original timings were spot on so I don't bother with it any more.

 

[zambezi]

if you have one of those cheapo trimmers from Lee, as they come with an attachment which fits into a cordless and securely holds the case head.

Sounds a good, but slowish option. Both 6.5x55mm and 30.06 cases sit in the 12mm socket and rotate without wobbling at low drill rpms. The upside is inverting the drill into a steel pan throws the case quickly allowing your non-drill hand to load the next case.

The .375 case head requires an imperial socket a little bigger than 13mm for best accommodation.

 

[andyk]

Maybe your solution is the better then, I’ve singed my fingers once or twice undoing the holder. I might give your option a try next time.

 

[zambezi]

Maybe your solution is the better then, I’ve singed my fingers once or twice undoing the holder. I might give your option a try next time.

Every annealing session I start with a bucket of waste brass to make sure I have the flame hot enough, my eye is seeing the colour correctly, etc. During this "calibration" phase, I use my fingers to remove the annealed case from the socket. If it was too hot to touch, or if the socket is warm, I am dwelling in the flame too long.

Trial and error suggests the flame is the right temperature when the black-red neck colour forms in sub 6 secs.

 

[zambezi]

A follow up to this thread on annealing...I came across a truly revelatory video on a common misunderstanding.

Starter for 10: tempilaq 750℉ changes colour at that temp. Brass anneals at 750℉...but only if soaked at that temp for one hour. I.e. to go fully through the re-crystalisation phase, brass needs to be held at that temp for one hour, by which time the head would be unserviceable.

Short synopsis of video's premise: a good and repeatable anneal of a case neck needs a temp greater than 1000℃, but for a very short duration, applied to the neck/shoulders only. And it is better to go a bit longer than a bit shorter on time as you will have more repeatable results.

It transpires that the method I developed above is probably on the money, but more by luck than judgement.

 

[Woodsmoke]

I was lucky enough to be gifted a set of annealing dies that cover everything from .22 up to the bigger magnums. They're aluminium, which acts as a great heatsink. And they fit into a cordless drill. A five second spin in a DIY propane blowtorch flame sees them done perfectly.

 

[zambezi]

I was lucky enough to be gifted a set of annealing dies that cover everything from .22 up to the bigger magnums. They're aluminium, which acts as a great heatsink. And they fit into a cordless drill. A five second spin in a DIY propane blowtorch flame sees them done perfectly.

View attachment 212544

Case-size-dedicated holders is definitely first prize.

But has anyone tried one of those universal socket thingies as a case holder? The type that have a raft of spring-loaded pins that hug a myriad different sizes/shapes?

 

[Redneck]

I have been using the best fit metric sockets and got on fine.

 

[zambezi]

I was lucky enough to be gifted a set of annealing dies that cover everything from .22 up to the bigger magnums. They're aluminium, which acts as a great heatsink. And they fit into a cordless drill. A five second spin in a DIY propane blowtorch flame sees them done perfectly.

View attachment 212544

That image inspired me to source some 1" aluminium round bar and some appropriate stainless rods. Machining some annealing holders per the image is [I hope] a pretty straight-forward proposition...

 

[Woodsmoke]

That image inspired me to source some 1" aluminium round bar and some appropriate stainless rods.

Great idea! Will you press-fit the stainless rod into the aluminium?

 

[takbok]

I've done similar with stainless bar and aluminium tube. The grub screw is redundant as I ended up with an interference fit.

 

[paul o']

Smart work

 

[zambezi]

Will you press-fit the stainless rod into the aluminium?

That had been the plan...ish. I drilled a 6mm hole for the 6mm rod today and then, once inserted, I tried to peen the outside of the ally to make a crush fit.

Fail. Even 4lb persuasion on outside of the ally round deforms the outer cylinder, but does not significantly reduce the inner 6mm - in short, it does not grip the rod.

I see two options for the rod-to-ally cylinder marriage: (1) Epoxy or (2) I draw a few fine strands of wire through the 6mm orifice first, and then drift the 6mm rod in behind.

Clearly Takbok has a lathe. Sadly, I do not. So perfect centers on the drill runs is not going to be a feature of my project. But it will work! Hope to finish up tonight and post a pic'.

 

[Alantoo]

A 1/2” square drive hexagon / Allen key works very well. The hexagon key runs true in the three jaw drill chuck, and a 308 case runs true in the 1/2” square socket. I just tip the annealed case into a water pot, not for any quench/heat treatment reasons, it just helps to clean off the soap…

Alan

 

[zambezi]

A 1/2” square drive hexagon / Allen key works very well. The hexagon key runs true in the three jaw drill chuck, and a 308 case runs true in the 1/2” square socket. I just tip the annealed case into a water pot, not for any quench/heat treatment reasons, it just helps to clean off the soap…

Alan

Yup. But I have three cases sizes to deal with and they correspond to 3/8", 12mm and 14mm/9/16".

For some of those combinations I had to also find my 1/4" drive to 3/4" adapter before I could chuck up in the cordless drill. Just a faff...

Having dedicated holders near the propane torch is defo first prize.

And on the matter of trueness: whilst the first 6mm pilot through the bar was not 100% centered, the case holding ream followed that pilot, so drill-spindle-to-case is true. It is just that the ally OD has a [minor] eccentric pitch.

 

[zambezi]

In the end, I super-glued the steel rods into the ally case holders.

Not as precise or elegant as Takbok's fabrication, but still a practical and workable solution given hand-tools only. Pretty happy with the outcome.

 

[Woodsmoke]

Looks like they'll do the job perfectly. Nice work! Satisfying as hell when a wee job like this works out, isn't it?