reduce a tin by another

[Nicholas Smith]

I need to reduce tin A by another tin B i.e reduce tin A where it rises abover tin B. I supose its like a super tin but I need to run volume calcs and understand this is not possable with supertins.
Any ideas
Thanks

Nick

[Lee Gregory]

I don't understand what you mean by "reduce tin A by Tin B" ?

Do you mean that a tin is to be formed that is
(a) Tin A whenever tin A is less than or equal to Tin B
and
(b) Tin B when Tin A is higher than Tin B