[Solved] Smithmagi: Mistake in sink calculation

Hi,

I just reached level 100 jewelmagus and tried to practice a bit on a Morello Cherry Blop Ring.

My issue is that I calculated a sink of 2. When I passed a Pa Int rune that resulted in:

Failure: -1 Range, +sink

So I calculated the following sink : 2 + 51 - 3 : 50.

Right after, I tried to recover the summon that disappeared earlier. According to my information, a Summo rune has a weight of 30 and as long as you have sink, it protects your characteristics from being damaged. So it should not have damaged my item anyway. Yet, the result was the following:

Success: -27 Intelligence, +1 Summons, -sink

How come I got -27 Intelligence? According to my knowlege, this means my sink was actually of 3. How could I have made a of 47 (50 calculated - 30 Summo + 27 Int) in the sink calculation?

I don't think I made any mistake but, even considering I made two mistakes and actually had a sink of 0 instead of 2 (first mistake) when I dropped the Range with a Summo rune instead of a Pa Int (second mistake). This would give a sink of 21. Still far from the sink of 3 that would have cause the -27 intelligence when I passed the Summo rune.

Here is a screenshot of my last results:
Can anyone explain my mistake ?

As a side note, I asked a member of my guild that is more experienced than me in smithmagi and he told me he also noticed unexpected damages to his items while he thought he had enough sink.

Thanks a lot in advance.

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Someone in my guild eventually figured it out. I had an over intel so it took the precedence against the sink. My mistake was that I considered max intel is 30 while it is 25. So this explains the issue and I still have 47 sink.