6 Attachment(s)
Salt Bath Annealing, Pro's and Con's.
I've been annealing my brass via the salt bath method for about a year now, so I thought I'd post some results for those contemplating starting to anneal their brass but have not decided what equipment to buy.
I purchased my kit from a supplier in Canada. http://ballisticrecreations.ca/salt_...aling-kit-rev/
Attachment 5849
I added a low cost multi-meter to monitor the temps (about 1000 F) and found a Lee lead pot melter on sale. I think my total investment was around $150.00 including extra salt media.
Here you can see the temp is 1026* F
Attachment 5851
Here is what the baffle/shell holder looks like.
Attachment 5850
Look at how benign that hot salt looks! Also side view of shell holder. I should have placed a case in it to show how it holds just the neck in the solution.
Attachment 5854
PRO.
1 First and foremost, it's CHEAP and effective. The only expendables are salt and water (no, you don't mix the two in the pot), and start up costs are reasonable.
2 You absolutely KNOW the temp of the media you are using to anneal your brass, so over heating and ruining the brass is simply not possible. I have left brass in the bath for 5 minutes trying to soften the case head. It got a little discolored, but apparently did not soften. Hardness was pretty consistent with virgin brass according to my test method (not scientific and quantifiable, but nonetheless workable). Therefore the consistency of the anneal is quite good using this method. NOTE: only the neck is submerged in the salt media.
3 It's quick. Really quick. I typically use 4 to 5 seconds of soak time and because the baffle plate has two holes, I can place one in the bath and while its cooking, take another case out and place it in the second hole. By counting continuously I place the second case at count 4 and remove the first case and drop it in the nearby water bucket at count 5. Then grab another case and place it at count 4 again and repeat. So every 5 seconds I am cycling a case in and out. That's 12 per minute.
4 Knocking the primer out before annealing is essential. Seriously essential! I had some FTF cases that I pulled down and forgot to segregate from the rest. Fortunately the primer blew after I pulled it out of the bath. I was using a steel pan to capture the annealed brass at that time and the force of the primer explosion flattened the case wall of an adjacent case. It also stopped my heart for a few seconds...LOL. So now I drop them in a bucket of water, both to wash off salt residue, but also just in case I get stupid again. But no further prior action is required such as sizing.
5 Warnings about 1000 degree salt and water not mixing are a bit overblown using this particular method. I've had cases that I SS pin tumbled and rinsed, but that even after blowing out with compressed air and drying in a hot box, still had some water inside. When it hit the hot salt, it sizzled a bit and that was it. Nothing more. I wouldn't pull a case out of a bucket of water and go directly into the sale bath just to test this scenario, but reasonable care keeps things pretty safe.
6 Consistency. This is where paying attention to soak time and media temperature becomes a little more important. As it turns out, shiny, polished brass does not turn bluish as readily as dull brass. So if a visible anneal is preferred as a consistency measure, go with unpolished brass and notice how far down the case the tint travels. My pot cools as I am processing brass, particularly large brass. So I will either stop and wait for it to come back up to temp, or simply add a second or two the the soak time and judge the anneal time by the color after it hits the water. I typically SS tumble afterwards to clean out all salt as well as powder and primer residue. But this removes the nice anneal coloration.
Here is a 308 case after 6 seconds at 1000*F with the neck and part of the shoulder submerged in the salt media.
Attachment 5852
CONS:
1 Although the Lee melter pot is reasonably priced, it clearly was not designed for use around corrosive salt as it's largely made of aluminum. When I replace mine, I'll use hi temp paint to coat the outside surfaces that get exposed to the salt. The other thing that failed early was the temp controller. When new, it held temps at 1000 F pretty consistently. But after a few uses, it began to wander a lot. So now I baby it, frequently unplugging it as temps go above 1100, or cycling the temp knob to get it to turn on again when temps go below 900. There's probably a much more expensive and better melting pot out there, but I continue to nurse mine along and it's doing the job so I'll keep using it for now.
2 You don't want to leave the salt in the pot in storage. It will draw moisture from the air and become wet. That will cause it to smoke considerably while heating up, and transport salt into the air of the environment you're using it. So have an air evacuation plan in place such as using it outside or in the garage with a fan blowing across the pot. Unless you don't mind rusting every tool you own along with your delicate measuring instruments. I put the cooled puck back in the jar the media came from (Ballistic Recreations) and that seems to work fine.
3 For those who prefer dirty, powder residue incrusted necks, this method will affect your neck tension. Some adjustments to the process will have to be made. Although by itself, the salt will not clean residue off the inside of the necks, it will have some affect, especially if you use a water rinse, so plan ahead. A separate neck lube step may be necessary prior to bullet seating.
4 Working around any very hot, 1000 degree liquid is quite dangerous, and the salt pot at working temperature looks completely benign, nothing like the blowtorch method of annealing. There are no visible warning signs of extreme heat such as smoke or the roar of a torch flame to warn of a of a serious burn hazard. The only giveaway is the meter registering 1000 F. So I clamp my pot down to my table saw so I can't trip over the electrical cord and cause a spill, and I wrap the electrical cord around the table several time too. I also warn anyone coming into my work zone to stay clear. For a very visual example of just how hot the salt is, I dip a wooden paint stir stick into the hot salt. It IMMEDIATELY catches fire on contact with the salt. Quite impressive to the casual bystander!
Procedures: Set up and use.
I start the process by mounting the Lee pot to a secure surface and place a 5 gal bucket half filled with water under the table/bench the pot is mounted on. I will use this to drop the hot cases into after annealing. I do this in the garage and open the doors so fumes don't linger around my tools and gages. I summer I will position a box fan to help move air.
I then pour the salt crystals into the pot, filling it nearly full and turn on the Lee pot. The salt will start to melt at about 375* and once melted I place the baffle/case holder into the pot and let it continue to heat. The thermocouple is inserted into the baffle and meter turned on to register degrees F.
As the media heats up, it's time to adjust the salt level in the pot. I do this by quickly placing a case in the case holder and withdrawing immediately. This will leave a crusty salt residue on the brass showing the salt level in the pot. I add or subtract as necessary to get the full neck submerged.
Once the salt is up to 1000*F, i start the annealing process by placing a case into one of the two holes in the baffle and start a rhythmic count. If 5 seconds is my preferred anneal time, I'll place another case in the second hold on the count of 4 and remove the first on the count of 5, dropping it in the bucket of water and taking another case from the box. By doing this continually I can process about 12 cases a minute.
One case just went in, other coming out, about as fast as you can do it.
Attachment 5853
My lee pot will gradually drop in temperature as the brass sucks the heat out of the media, so stopping to let the pot heat again and/or increasing the dwell time in the pot to compensate becomes necessary. There are home made digital temperature controllers that can be used to make the pot work much better than the simple LEE controller with some rewiring. It's not expensive but I've not got around to it yet, so I baby mine along. https://youtu.be/vwDgkrNMJQA
Once I've finished my annealing, I unplug the pot, remove the baffle and thermocouple (remember, they'll be quite hot) and let everything cool. The salt puck, once cooled can be tapped out of the pot and placed in an airtight jar or the original container. You can use a damp cloth to wipe the pot down if you like, but the aluminum will still want to corrode.
The annealed brass is retrieved from the bucket and processed as you would with any wet brass.
I'll wrap this up now. Hopefully this has been informative and helpful to anyone contemplating getting into annealing. Comments and questions are appreciated and expected. So fire away!
Good Shooting.
SIlicone seal mentioned on Salt BAth Annealing
Quote:
Originally Posted by
Texas10
I would be interested in reading your experience with PID controller when you get it working, Phil.
And since you're going to disassemble the unit it wire for the PID, I highly recommend the high temp paint on all aluminum parts. Also a high temp silicon seal on the lower pot cap to keep salt from seeping under the cap.
Please write back with your PID building experience and overall satisfaction with it.
One other caution when using the Ballistics Recreations thermocouple is be sure you don't twist the plug end. The wires are exposed inside the plug and when twisted they'll short and you'll get erroneous temp readings that will throw your PID into conniptions.
I just saw this article. I have been salt bath annealing since 2019 and love the results. My Lee Lead Melter just blew a heating element and in the process of cleaning it up to get ready for a new element I ran across your article and comments. I've been trying to find a seal/sealant and I was wondering if you could point one out to me. I'm not having luck as the temp of the salt bath is about 525-550C. I do use a PID controller set up I built. I'm also toying with the idea of removing the resistor on the Lee and just allowing the PID to have all control. Any Wisdom and comments would be greatly appreciated!
