Craft mechanical trap or magic item...

[Eldon RowDragon]

Hi All!
Please help me understand this:
To make a mechanical trap, the characters have to roll the DC every week until they finishes it. The DC is realtively high.
To make a magic item the magic user rolls only once and the DC is low.
What?!
Let's see an example:
The rogue wants to make a tricky CR6 mechanical trap without any other modifications. Craft DC is 25, cost is 6.000 gp (60.000 sp). The trap is finished in 96 weeks if the rogue reaches DC25 every time.
The wizard wants to make a very useful Ring of Freedom of Movement. Craft DC is 12, cost is 20.000 gp. The ring is finished in 20 days.
What?!
If the rogue rolls 21+, she doesn't make any progress. If she rolls 20 or less, she ruins the half of the raw material.
If the wizard rolls 8+, the ring will be useless and the material is lost, if her roll is 7 or less the ring will be cursed.
What?!
To cast Freedom of Movement the wizard needs to have an Int14 (mod: +2). Spellcraft is class skill and Int based. The wizard has an automatic 6 points on it if we foolishly suppose that she put only 1 skill point on it and doesn't improve her most important skill anymore.
So, the question is: where is the balance? Or a simple logic?
Thanks for advice.

[MurphysParadox]

Balance? Logic? There is only magic.

PCs aren't generally meant to make non-magical stuff (except the Alchemist, though it gets a handful of class features which makes it actually practical). The GM can fiddle with the system if they want but it is hard to tweak the numbers and still be reasonable; you almost have to redo the entire formula. A good guide are the Alchemists class features (use gold instead of silver pieces, you get several of the item instead of just one, you get numerous bonuses, etc).

[Eldon RowDragon]

There is no spoon...
I just wanted this answer from others too. :)
Thanks!
Sometimes it happenes that the players make things like traps or magic items. So I was curious. :)

[MurphysParadox]

Honestly, if the PC really wants to make traps, let him. Create a feat called Craft Trap and use the exact same rules as magic item crafting. Use Craft (Traps) instead of Spellcraft and daily crafting rate is 1000gp per 8 hours. Let him increase DC by +5 to make that 2000gp in a day. Cannot craft traps with a CR higher than his level and any magical traps still require someone to provide the necessary spells. Make this feat accessible through a basic rogue talent as well, for the fun of it.

This lets the player do what he wants at a reasonable and comparable rate to magic item crafting. It won't break the game and it'll make the PC happy to do something he wants to do.