I am looking over both and I am wondering if I want to have my gnome make a collaspable kit. If it is not as good or better for crafting stuff I do not think I want to make them
Move the Collapsed Fletching Kit (or any other Collapsed item) to an open spot in your inventory and right-click it. This will trigger its effect, meaning you must stop casting other spells to trigger it (or singing other songs if you're a bard). You will then summon a Collapsible Fletching Kit, and it will display on your cursor. Move that to your inventory and use it as a regular fletching kit.
When finished with the Collapsible Fletching Kit, you may destroy it if you desire, but note carefully the difference in spelling between the two items: the Collapsed Fletching Kit is the triggerable item, and is what you want to keep; the Collapsible Fletching Kit is the summoned container that you may destroy.
I did a combine for a Nightmarewood Compound bow in the summoned kit, so it can take the place of the Planar Fletching kit. Not sure if the same goes for the other Collapsed Kits though. I also haven't tried Cultural combines in it either.