It gives you 6 more usable hours in the day, but it doesn't change the rules or limits on what you can do in a 24-hour period.
Yes, you can use the extra time to craft magic items, but crafting can only be done in 4-hour or 8-hour blocks. And, if crafting an item requires you to expend a spell, then that time counts towards the restriction that spell slots expended in the last 8 hours before your meditation/memorization cannot be recovered.
Recent Casting Limit/Rest Interruptions: If a wizard has cast spells recently, the drain on his resources reduces his capacity to prepare new spells. When he prepares spells for the coming day, all the spells he has cast within the last 8 hours count against his daily limit.
These same restrictions apply to bards, clerics, etc.
It gives you 6 more usable hours in the day, but it doesn't change the rules or limits on what you can do in a 24-hour period.
Yes, you can use the extra time to craft magic items, but crafting can only be done in 4-hour or 8-hour blocks. And, if crafting an item requires you to expend a spell, then that time counts towards the restriction that spell slots expended in the last 8 hours before your meditation/memorization cannot be recovered.
Would be possible to craft magic items for 8 hours and mundane items for 12 hours (8 + 4)?
Skarm
Unless I am missing something, I don't believe RAW states how many hours/day are spent when doing mundane crafting. There are some exceptions (removing the "broken" condition from an item takes 1 hour/point of damage), but in the general case it is not defined.
The crafting rules in PF are pretty messed up. Unchained helps a lot, but it still doesn't answer this question to my knowledge.
So...ask your GM. It's reasonable to assume it's 8 hours of progress like crafting magic items, but by RAW there's no hard number there.
When I'm crafting wondrous items, would I be able to do this in a dungeon while my fellow adventurers are sleeping? As I just need 2hrs of sleep.
Do I need anything special to craft these wondrous items?
Have you actually read the item crafting rules?
The caster can work for up to 8 hours each day. He cannot rush the process by working longer each day, but the days need not be consecutive, and the caster can use the rest of his time as he sees fit. If the caster is out adventuring, he can devote 4 hours each day to item creation, although he nets only 2 hours' worth of work. This time is not spent in one continuous period, but rather during lunch, morning preparation, and during watches at night. If time is dedicated to creation, it must be spent in uninterrupted 4-hour blocks. This work is generally done in a controlled environment, where distractions are at a minimum, such as a laboratory or shrine. Work that is performed in a distracting or dangerous environment nets only half the amount of progress (just as with the adventuring caster).
Each magic item has a section telling you what it requires to make. You don't need anything else special to craft in a dungeon, you just don't get as much done in a day.
When I'm crafting wondrous items, would I be able to do this in a dungeon while my fellow adventurers are sleeping? As I just need 2hrs of sleep.
The caster can work for up to 8 hours each day. He cannot rush the process by working longer each day, but the days need not be consecutive, and the caster can use the rest of his time as he sees fit. If the caster is out adventuring, he can devote 4 hours each day to item creation, although he nets only 2 hours' worth of work. This time is not spent in one continuous period, but rather during lunch, morning preparation, and during watches at night. If time is dedicated to creation, it must be spent in uninterrupted 4-hour blocks. This work is generally done in a controlled environment, where distractions are at a minimum, such as a laboratory or shrine. Work that is performed in a distracting or dangerous environment nets only half the amount of progress (just as with the adventuring caster).
In theory the ring may let you work a full 8 hours in an adventuring day (mostly while on watch but not all), netting you 4 hours of progress. Your GM may not agree with this, so check with them before making plans.
Do I need anything special to craft these wondrous items?
To create a wondrous item, a character usually needs some sort of equipment or tools to work on the item. She also needs a supply of materials, the most obvious being the item itself or the pieces of the item to be assembled. The cost for the materials is subsumed in the cost for creating the item.
The exact equipment you'll need depends on the item; consult your GM.
The cost of making the item is assumed to cover the cost of the equipment needed for crafting.
As for using your extra free time to craft, you need that full 8 hours in a “fairly quiet, comfortable, and well-lit place”, which isn’t always easy to find on an adventure. The 4/2 hour progress is what you can get done in non-optimal conditions.
This itemallows me to sleep only 2 hours to regain use of all my spells. Would I be able to use this ring to spend 6 hours every night crafting wondrous items?
RAW no, per magic item creation rules:
If the caster is out adventuring, he can devote 4 hours each day to item creation, although he nets only 2 hours' worth of work. This time is not spent in one continuous period, but rather during lunch, morning preparation, and during watches at night.
That's it. If you are out adventuring, you get four hours of work netting two of item completion. The fact that you have more time to spare doesn't nullify this rule.
Still, a GM may allow your character to use the "dedicated time rule" in some scenarios, like when you finish an adventuring day "early", if there's enough time to spare:
If time is dedicated to creation, it must be spent in uninterrupted 4-hour blocks. This work is generally done in a controlled environment, where distractions are at a minimum, such as a laboratory or shrine. Work that is performed in a distracting or dangerous environment nets only half the amount of progress (just as with the adventuring caster).
For your character to be eligible for this, you GM must consider that you have a free 4-hour block during your adventuring day, since, unlike the "adventuring time", this block must be continuous and completely dedicated to crafting. You can't stop/pause working during this 4h period, or "share" it with other duties.
I have a handy haversack (I got 7 str so bag of holding is kind of heavy), what would I/Do I need to throw something in there to help me craft the wondrous items? Or do I need a lab or something which won't allow me to craft mobile style.
What you need will mainly depend on the type of magic item you're creating. Check the Magic Item Creation section for the items and the most common components, but basically, for anything that's no weapon or armor (that require a potent enough heat source and some tools you won't probably find outside of a smithy), for most other items you can normally find a "portable" version of the needed tools.