Left tumbler on all night accidentally.

[Benjamin Graul]

Well, I pulled a dumb move and forgot to turn the tumbler off before I went to bed. It has now been going for about 11 hours. Should I be worried about brass being too thin now? Opinions?

 

[OKyote73]

It's fine..... . Just extra shiny!

 

[rwj]

Doubtful... you may have to chamfer the case mouths to remove peen marks...

 

[dcali]

Assuming you mean a vibratory tumbler with corn cob/walnut, you can leave it on for days and it won’t thin your brass. Probably months. It’s fine.

 

[338 dude]

I have mine running on a timer for that very reason

 

[NorCalMikie]

More problems if you're using Stainless Steel Pins. Cob or Walnut, just cleaner.
I run mu Thumbler's Tumbler with SS pins all night. They ARE clean when I shut it off.

 

[Dusty Stevens]

No problem

 

[centershot]

I have mine running on a timer for that very reason

^^+1

 

[STOMP442]

Overnight is my preferred way to tumble.

 

[sqrlgtr]

My all night “tumbleing”is long gone.Wait what was we talking about?

 

[Ken]

I have mine running on a timer for that very reason

Yep, I have a coffee pot type timer on mine--works great

 

[243winxb]

No thinning problem.
But squeaky clean brass may need some extra lube on the first few brass into a full length die.

The surface zinc may have been partly removed?

 

[BronzeArcher]

I've got Lapua brass that has been tumbled, reloaded, and fired 14 times. Tumbling is for 4-5 hours each time, so well over 50 hours total. Not a problem. I guess it is possible that excessive tumbling may shorten case life, but I tend to think firing and sizing wears on brass much more than tumbling.

 

[Fotheringill]

Been there, done that a few times. No visible or results oriented effects. I was wondering what the dog was barking at the last time at the basement door. I went down to the basement and the only thing stirring was the tumbler. I immediately changed his name from Scruffy to Vigilant.

 

[riflewoman]

No thinning problem.
But squeaky clean brass may need some extra lube on the first few brass into a full length die.

The surface zinc may have been partly removed?

There is no surface zinc as brass is a solution. The chemical bonds are much tougher than the mechanical abrasion of tumbling.

 

[Uncle Ed]

If you wet tumbled with stainless steel media for 11 hours you are going to have badly peened case mouths. They will need to be trimmed and chamfered to remove the peening.

If you used a vibratory tumbler you should just have very clean brass and nothing to worry about.

 

[243winxb]

The tumbling effectively creates a harder "skin” on the surface which is undetectable even under 200X magnification or higher

https://www.ampannealing.com/articles/40/annealing-under-the-microscope/

Zinc is a lube. IMO.



Brass is harder then Zinc? http://www.drill-hq.com/2011/11/hardness-scale-for-various-materials/
Zinc may be depleated, some, if annealing temperatures are to high.
Not saying i am correct. Always willing to learn.

 

[Dusty Stevens]

If you wet tumbled with stainless steel media for 11 hours you are going to have badly peened case mouths. They will need to be trimmed and chamfered to remove the peening.

If you used a vibratory tumbler you should just have very clean brass and nothing to worry about.

The mouths will be peened the same at 1hr. Couple quick spins with a debur tool and youre back in business

 

[Uncle Ed]

The mouths will be peened the same at 1hr. Couple quick spins with a debur tool and youre back in business

When wet tumbling the case mouths are hit by the other cases, and the longer the cases are tumbled the more the case mouth is hit and peened.

Below on the left a case I forgot and let tumble all night, the case had been trimmed and deburred before the last firing. On the right is a new case right out of the Winchester bag and shows the effects of factory tumbling.

Bottom line the longer the case is wet tumbled the more the case mouth will be hit and increasing the peening.

 

[drano38]

+3 on using a timer (but its a mechanical 24 hour one, so if I completely forget, it comes back on).
I also set a timer on my smartphone.
I use corn cob, so agree with above posts, it can go for days. Other media types are not as friendly.