Quenching shatter chance?

[Maelstrom]

So I finally got to iron and started quenching and tempering tools.  I have had almost half of my tools shatter (12 total and 5 have shattered) after quenching and tempering less than 4 times.  Shatter chance does not exceed 20%.  Methinks my RNG luck isn't THAT bad.

What say you?  Is the published shatter chances seem off to you?

[LadyWYT]

40 minutes ago, Maelstrom said:

What say you?  Is the published shatter chances seem off to you?

That seems a little high to me, so I'd say you've just gotten unlucky this time around. If you want to simplify the process though, I made a mod for that! 

https://mods.vintagestory.at/improvedquenching

It still retains some shatter risk for certain benefits, but overall it changes the system to a "one and done" process.

[Maelstrom]

Definitely will look at it tomorrow.  I spent 2 in game days just trying to get a pro pick and scythe.  pro pick broke once and the scythe broke 3 times!  one of them on the second quenching.  I always temper after quenching.  RNbeGeezus hates me.

[Rainbow Fresh]

I made my first iron chisel and it broke on the baseline 5% chance on the first ever attempt. Needless to say, a refunded replacement came straight out of the creative inventory and this shit is getting modded out.

[MKMoose]

6 hours ago, Maelstrom said:

So I finally got to iron and started quenching and tempering tools.  I have had almost half of my tools shatter (12 total and 5 have shattered) after quenching and tempering less than 4 times.  Shatter chance does not exceed 20%.  Methinks my RNG luck isn't THAT bad.

What say you?  Is the published shatter chances seem off to you?

First, calculating the survival chance of a tool only requires that you multiply the survival chance (1 - shatter chance) for each iteration. In your case, assuming you've tried quenching each of your tools 3 times, with a temper after each one (besides the last which doesn't matter), the overall survival chance is approximately 0.95 * 0.92 * 0.895 = ~0.78. For 12 tools, that gives you on average 12 * 0.78 = ~9.4 surviving tools.

Using a binomial distribution (for example with the Desmos Graphing Calculator - you can try something like this document to see different configurations yourself) for 12 tools with a 78% survival chance, we can calculate an ~10% chance that 5 or more out of 12 tools break (i.e. up to 7 favorable outcomes). Low but not terribly unusual, as far as probabilities go - it's twice the chance of breaking a tool on the first quenching.

Edited 3 hours ago by MKMoose

[Professor Dragon]

Well, my very first quenched item, my steel hammer (when I was just starting steel and didn't have a lot), shattered on that 5% chance.

"Typical" I thought.

I'm just doing a single Quench and one Durability buff now - I'm discouraged from trying more.