Combining Formulas to craft an item

[Madur]

So lets say i have the basic crafting book(all formulas lvl 0),
the silver formula for (2 lvl) and the weapon potency rune formula (2 lvl).

Can i craft(RAW?) a magic(potency) silver sword in 4 day if i pay the full price?

And how would i calculate the price?

[NielsenE]

As far as I can tell, there's no explicit way to combine formula. You need the precise formula for the item you are trying to make.

We have one example to my knowledge across the published modules/APs/PFS2 scenarios that is close to this. (Its a special metal + item combo, no magic involved). And it suggests that you would need the formula for a '+1 silver sword', as a singular named formula. In your case it looks like its still be a common formula, nothing about it is uncommon, so it should be possible to find, and I think it would still be a level 2 formula.

Cost wise, I think it would be 35 + 40 + 4gp per bulk of the weapon.

In a home game, if a character had both the formula for the rune, and the formula for silver sword. I'd probably charge the the cost for another level 2 formula (+1 silver sword) without making them track it down. Just representing the cost of them combining the two, writing out their plan for how to create it, etc. That might be stepping on the Inventor feat's toes a bit though.

[Madur]

40 gp + 4gp per bulk are from the low gradsilver weapon.
35 gp are for the potency +1 rune.

Got it.

But for the Formulas.

Do i need a specific formula?

Again lets say i have crafing book,
the silver weapon formula (Do i need to buy every weapon seperatly?).
and i have the potency rune formula.

Do i really need a +1 silver sword formula to make it in 4 days?

EDIT:Ok, i guess you need to experiment to get it right. -> Formula

Nonetheless it should be possible to craft the sword with the 2 formulas in 8 days.
Am I right?
4 Days for the silversword and 4 days the etching.

[NielsenE]

As far as I can tell, yes you need a 'silver longsword formula', then a 'silver mace formula', etc there's no generic 'silver weapon' formula. That would be a level 2 formula, common, so 2gp.

Yes, doing it in 2 4-day chunks is probably easiest.

4 days, 44gp for the silver longsword (or which ever other 1 bulk weapon you're making after having the correct formula)

4 day, 35gp to etch the rune onto it.

[Themetricsystem]

By RAW, you need a unique Formula in order to make any of the following:

Longsword (Included in Basic Crafters Book)
+1 Potency Rune
Low-grade Silver Longsword
Standard-grade Silver Longsword
High-grade Silver Longsword
+1 Longsword
+1 Low-grade Silver Longsword
+1 Standard-grade Silver Longsword
+1 High-grade Silver Longsword
------

Moving past this, I cannot really speak to the RAI but at my table I wouldn't require each of these things and would allow the PC to "combine" Formulas to make what they're working on because I feel it's punitive to crafting focused characters but if you're using the RAW as your guideline... well let's just say I hope you don't have to deal with anyone who wants to make Scrolls because the problem is SOOO much larger with them since each Scroll of any given spell is absolutely 100% a different uniquely named Item and will again, need a specific Formula for each Spell in addition to another Forumla for every Heightened level of every spell.