1-2
8 handed Hero has £312 v2 covers, v1 has about 250ish....not relevant I don't think.....

Hero finds tt utg and makes it 12 (standard size for me here)
V1 calls from CO
V2 raises from bb to 42
.... I have been playing with v2 for over 4 hours, he has 3bet once pre and had aa, he flatted tt from button vs a £8 raise earlier,and he flatted ak from bb earlier vs raise of 13 from me before..... So we can be pretty certain villan has qq+ here
So it's costing 30 to call this raise,I expect V1 to fold most of the time here....he is pretty passive generally, might call here but I doubt it.
I'm never jamming here, so do we make the call? Stack will be 270 after making the call, so just under 10:1 implied odds....I expect villan to stack here if he has am overpair to the board....
I made the call, just wanted to check if the maths stacks up.

You are actually getting hair over 10-1 because the money in the pot also counts towards what you can win. People usually ignore it because if your looking at limped pot with a single raise the money in the pot is insignificant. Once you are in a raise, call, reraise situation the money in the pot matters.

The money in the pot makes the call thin but not bad. I would make this call sometimes if I was confident enough that V2 will stack off. Really though you would like V1 to call behind for you to call. That both improves your pot odds and makes SPR low enough that it will be hard for V2 to not stack off.

Your implied odds are 30:24+42+270=30:336. About 11:1. I would like it to be a touch higher here to call, but people can differ. If you had 400 effective I call. While your around 7.5:1 to flop a set, you don't always gii when you do (sometimes he has AK and whiffs, sometimes he has KK or QQ and an ace flops, etc.), and then a meaningful percentage of the time when you do gii, he ends up winning (either because he coolered you by flopping a bigger set or because he sucks out on you).

Probably a slightly losing call, but close.

Being pretty confident villan has qq,KK,aa here l, if we do flop an ace can we not take it away on a later Street and make up for some lost equity?
I have always worked off 10:1 generally but I am usually deep enough for it to be pretty trivial, this was very marginal which is why I checked it out....
Is there a standard number to work off in these sort of spots, we are at 11:1.... Is 12:1 better? 13:1?

Here's my take on the math.

We're about 7.5:1 against flopping a set. When we don't flop a set, let's assume we always fold, so we lose $30. When we do flop a set, against a range of AA-QQ, let's assume we always get it in on the flop no matter what the other cards are on the flop. If we're up against a range of AA-QQ, and all we know is that 1 of the cards on the flop is a T, we have 80.7% equity, which I'm going to round down to 80% to make my life a bit easier. So when we flop a set, 80% of the time we win $336 and 20% of the time we lose the $30 we're putting in pre + $270 more. So our EV when we flop a set is .8*$336-.2*300=$208.8. 7.5 times we lose $30, so that's -$225, and we don't win enough when we bink to make up for it.

Now, let's assume we had $432 back to start the hand, or $120 more, which would give us 15:1 implied give or take. We still lose the same $30 when we whiff. When we flop a set, 80% of the time we win $456, and 20% of the time lose $420, so our EV when we flop a set is $280. That's well bigger than our risk adjusted -$225 when we miss, and pretty clearly shows 15:1 is good enough IO.

Basically, I'd never go less than 12:1, and really want 15:1. While you're right that sometimes we can take it away on ace-high flops, that by definition means we don't have the same implied odds on those flops. Similarly, you may also say that we can sometimes get away from set over set, but that again cuts into our implied odds. What this really shows is that it's hard to set-mine in 3-bet pots.

^Thankyou for spending time doing my maths for me...... So looking again, I think the tipping point is round about 350.....
I imagine when V1 calls this pre-flop also, it makes the maths stack up nicely....

I will look for 12-13x next time when mining.

Fwiw:
Hero calls, v1 calls,

Flop comes 10,8,4cc
Hero checks, v1checks, V2 bets about 70
Hero calls, v1 folds
Turn comes 2
Hero checks,villan bets about 130
Hero shoves, villan calls
Villan had aa
V1 says he had ak later in the hand when talking to another player....
Fish got to get lucky sometimes......

Yeah, $350 is around the tipping point and that's 12:1, but the assumption you always gii may be flawed. I would usually aim for 15:1, and maybe go down to 13 or 14:1 here in a 3-bet pot where we have position. It's also helpful that V1 can come along and improve both our direct and implied odds.

But generally, if you're making a mistake here it is likely overestimating your implied odds, rather than underestimating them. If V 3-bets with only half of his AK combos, that means that almost half the time he has AK and your only going to stack him if an ace or king hits.

If villan can show up with ak here then we win the pot if an ace or a king doesn't hit though as well....the waters become muddied the more combos we give our villan, but I said in op I was pretty sure this particular villan was only 3ING qq+..... He has flatted both ak and tt to raises in previous hands and had only made one 3bet in four hours which was aa.....
I know this could be an anomaly but you have to go with the info you got, I played the hand assuming he had qq+ and it's just a maths problem from there..... One that I mis-calculated, but it wasn't terra-bad so im ok with that.

It's a pretty common spot I imagine, and normally the play is obvious, just for some reason this particular time the stack size was just awkward..... 100bbs easy fold, 200bbs easy call, 150 and it's meh...

Thoughts on villans play here? I never want to be stacking 150bbs with one pair, but surely my range is waited much more to JJ/qq than anything else here? Cooler for villan?

On the first point, the question is whether you call a c-bet on a flop without an A, K or T. If not then it doesn't matter if he has AK as you'll fold most of the time anyway. If so, then you're not set mining and while you win some pots without a set you lose more when he has an overpair. You can't assume you call when he whiffs and fold when he hits though.

My point is that when we calculate the implied odds like we've been doing we're figuring out the break even point if he always gii when we hit a set. That is by definition an optimistic assumption, or at least it's never conservative. So at best the call is break even but it's never plus EV and probably is minus EV because he's folding some percentage of the time. Getting more like 15:1 (or going multiway like you did here) is really necessary to have a plus EV spot.

I'm fine with V's play except I'd have 3-bet to $50. SPR heading to the flop 2.5:1 so I'd feel committed with AA on all but the worse run outs. He could have sized a bit bigger to gii on the turn. As you noted you can have worse overpairs here to balance your sets. You could also have A high club draws if he doesn't have the Ac.

The situation is a bit better then what you suggest because hero knows what flops to give up on. If hero can fold flops with two cards in the AKQ range then hero's equity is closer to 85%. That is enough to push it back into being profitable. That is why pinning villain's range down to big pairs is important, when set mining this thin hero has to be pretty confident villain doesn't have AK in their range.

There isn't a fixed rule because how good your opponent is makes a huge difference. If villain is a fish that always has QQ+ and will always stack off with an over pair then hero can squeeze by with 10-1 but that is the absolute bottom and never super profitable. Against a decent opponent that can sometimes get away from over pairs on ugly boards and sometimes is 3 betting AK then 15-1 is better. If opponent is actually good and has some bluffs/light raises/mix it up hands in their range and will play smartly post flop then 20-1 is better. The good opponent will be harder to stack when behind and will sometimes flop surprising hands that are good for stacking hero.

That type of opponent also matters. When your squeezing under 15-1 you want stations or super aggressive opponents. The stations can't get away from their over pairs even when the board is ugly. The super lags and maniacs are always going to bet flop and turn and will pay you something even when they have air.

Disagree that you can materially improve your EV by folding flops with with two cards in the AKQ range. TT has about 42% equity on AKT, AQT and KQT flops given the card removal effects. We're not nearly deep enough to fold a set here, especially because H will invariably have put some money in post-flop before even considering folding. If we can find a fold we're bound to be cutting into our IOs in other spots where V is way behind.

grunch: you pretty much need at least 12:1 minimum to set mine. and that is only when you put opponent on KK+. chance of flopping a set is 8:1 and some of those times you are going to lose to a bigger set, or straight or flush. and sometimes villain will lay down his KK+ when we do hit. ie Ace flops and he has KK. 10:1 is definitely not good enough to call here. based on the read that he flatted AK and TT i think this is a spot 12:1 is right. without being able to put villain on a monster i go with 20:1 for setmining.