baking brass after ultrasonic cleaning

[blitz]

did some brass prepping the other day and after running some brass (300wm) through the ultrasonic we decided to bake it to dry it out. set the oven to 400 and threw the brass in once the oven reached 300. we left it in for 15 to 20 minutes.
the temp was at 400 for about 10 minutes of this time.

anyhow i noticed the brass got a little dis-colored, i know this is a under the temp that it takes to anneal a case but i am just wondering if i have anything to worry about.

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[oknow]

did some brass prepping the other day and after running some brass (300wm) through the ultrasonic we decided to bake it to dry it out. set the oven to 400 and threw the brass in once the oven reached 300. we left it in for 15 to 20 minutes.
the temp was at 400 for about 10 minutes of this time.

anyhow i noticed the brass got a little dis-colored, i know this is a under the temp that it takes to anneal a case but i am just wondering if i have anything to worry about.

yes, you will not have brand new looking brass.

 

[blitz]

yes, you will not have brand new looking brass.

yes, i have definitely noticed that but if that is the worst part of it i really don't care.

 

[oknow]

yes, i have definitely noticed that but if that is the worst part of it i really don't care.

I know you baked them for longer than what happens when you shoot them but I think(not positive) they get hotter than 400 for a short time.

 

[TRD1911]

I use a food dehydrator after sending my brass through the wet stainless media. Doesn't affect the brass or discolor it. That may be an option if you are worried about annealing your cases in the oven. From what I have read from guys doing the oven method is to leave it on the lowest possible setting with the door cracked.

 

[ma96782]

Did it end up changing the metal's properties?

A: I don't know. But, why did you use 400 degrees? You could have used the lowest setting (say about 200 degrees) for a longer time. Or, more importantly.......sunshine works and it's free.

Anyway......whatever. It's your brass.

Aloha, Mark

 

[elsie]

Cooked too long and at too high a temp. The idea is to rapidly evaporate the water which can be done at around 200 degrees for about 5 minutes, which is my procedure. Even if there's a little dampness left, they're warm enough that they dry quickly.

My metallurgy isn't strong enough to know whether or not you've annealed the cases or not.


elsie

 

[blitz]

well luckily i just did 40 or so cases so i am not at too much of a loss if i toss them in the recycle bin.

 

[P7M13]

Dude,
170°F for 15-20 minutes. Dry, shiny Brass, no discoloration, no muss, no fuss. WTF were you trying to do -- anneal them at the same time?
Your brass, though discolored, is fine. Load it, shoot it, and betcha your discoloration will come out in the next US cleaning.
Annealing requires hotter temperature, 750°F (900°F Max) and must be isolated to the neck and shoulder ONLY.

Deadshot or AMProducts -- Care to comment?

 

[deadshot2]

I'd hate the idea of wasting electricity for the oven. When I clean my brass in the SS media and need to dry the cases, I just shake them in a towel real good then anneal. I time my cleaning/annealing cycle so they coincide. Only clean about every 3-4 firings and ditto for annealing.

The heat from annealing dries the cases real quick and no "over-cooked" brass in the oven.

For those that don't anneal, just spread the cases out on a towel after shaking as much water as possible of them and put a fan on them. Same way carpet cleaners will dry a carpet out. If you rinse in really hot water after the cleaning process they will dry quickly.

 

[AMProducts]

I have a metal box (40mm ammo can) I cut a big hole in one side that fits a hair dryer I picked up at the 99c store, and drilled a bunch of holes in the other side to let the air out. It will dry ~2500pcs of .223 rem brass in about 15 mins.

Forced air and agitation are the best methods for drying brass, the heat is just a bonus.

Also, if you want "brand new" looking brass, the only way to really get it is to use corncob with a wax based polish, this works best. The steel pin media does a good job of removing all the junk that a polishing regimen won't, however it does little to protect the surface so it can be oxidized readily.

 

[blitz]

gonna have to try the ammo can idea. thanks for the tip. most of the time i just tumble my brass so the ultrasonic doesn't get used much.

 

[Modly]

I think they'll be fine. It was 15 minutes at most, and the oven never got to it's full temperature.

I am thinking of trying an experiment though to see how hot they actually got. We'll bake some of the scrap for roughly the same time, and see if we can measure the temperature with your thermometer.

Being that they were wet when they went in, I'll bet they never went over 300°F by the time they were pulled out. If all else fails, I'll do a test fire with it.

 

[deadshot2]

The steel pin media does a good job of removing all the junk that a polishing regimen won't, however it does little to protect the surface so it can be oxidized readily.

Add some of the water soluble car wash/wax liquids that are available now to your water/stainless steel pin mix. The "wax" that leaves a water beading shine on your car will do likewise with your brass. That will eliminate the need for the Dawn and cut back on the tarnish.

 

[SinisterSouthpaw]

Ain't those US cleaners real time savers, though?

 

[AMProducts]

Add some of the water soluble car wash/wax liquids that are available now to your water/stainless steel pin mix. The "wax" that leaves a water beading shine on your car will do likewise with your brass. That will eliminate the need for the Dawn and cut back on the tarnish.

This is a really good tip, I'll have to try it next time I'm running some stuff. Lately I've been doing a pre-wash (before sizing) to remove all the range dirt, then dry it apply case lube and process it, then wash it again (to remove all of the process lube), dry it and then run it through the big vibratory polisher. The most sensitive issue to me is process time, using the cement mixers to do washing speeds things up quite a bit, I'm not really sure how I would do a separation of the steel pins, at the moment I'm using the ceramic triangles (because they won't get inside the casings) but I do need to be very careful to make sure broken ones don't get into the case mouths during the post size polish/wash. Then the corncob tumbling to apply a wax and final polish.

After this, the brass looks brand new, and processing time for 50k pieces is about 8hrs.

gonna have to try the ammo can idea. thanks for the tip. most of the time i just tumble my brass so the ultrasonic doesn't get used much.

It works really well, the only downside is it's getting to be a bit small for my needs and I'm looking at industrial parts dryers.

I think they'll be fine. It was 15 minutes at most, and the oven never got to it's full temperature.

I am thinking of trying an experiment though to see how hot they actually got. We'll bake some of the scrap for roughly the same time, and see if we can measure the temperature with your thermometer.

Being that they were wet when they went in, I'll bet they never went over 300°F by the time they were pulled out. If all else fails, I'll do a test fire with it.

I think the bigger issue here is this is one of the slower ways to do this. Also, if you have water droplets on the surface baking will just create a mark on it. Forced air is a better method unless you have a convection oven.

 

[blitz]

thanks for all the tips guys! very useful info here. really appreciate it.

ps. it is a convection oven.

 

[deadshot2]

I'm not really sure how I would do a separation of the steel pins

A traditional "bingo ball cage" type media separator works great.

For large quantities just adapt a stainless steel washing machine tub. Maybe mount it on a cement mixer hub and place a tray beneath to collect the pins. For large quantities of pins and water, make the tray with high enough to contain the pins but let the water drain from a "waterfall lip".

 

[P7M13]

thanks for all the tips guys! very useful info here. really appreciate it.

ps. it is a convection oven.

Count your blessings that mama doesn't mind.

 

[Modly]

Count your blessings that mama doesn't mind.

Not a worry. The three guys that live here pitched in to buy the stove.