I have just noticed that all crossbows weigh more than the resources used in order to produce them e.i. 1 branch (5.5 lbs) can either be turned into a light crosbow (6 lbs) or a heavy crossbow (9 lbs).
Furthermore, I think that the most important part of the crossbow "the prod" has been left out of this recipe, this prod was before 1500 made from either wood or composite prods made of horn, wood and sinew. After 1500 these prods were replaced by steel prods, which resulted in a much better bow. So I would suggest that the recipes are altered from:
1 plank
1 bow string
to
1 plank
1 metal prod * (for the crossbow in question heavy or light)
1 bowstring
(1 firing mechanism)**
* I suggest that this metal prod is made from (+0), iron (+1), adamantium (+2), and mithril (+3), respectively. I suggest that these prods are made under weapon crafting, since it must be the craft closest to what would be needed in real life. Furthermore, if a iron prod was made by casting it (tinkering), a prod would result with absolutely no flexibilety. I suggest two different recipies
Prod for light crosbow (2.5 lbs):
2 metal ingot (of the mentioned metals)
1 small mold
Prod for heavy crossbow (5 lbs):
3 metal ingots
1 small mold
** the firing mechanism could be added as well since this must be considered more important than the wood used for the body of the bow. This firing mechanism could also be placed under weapon smithing with the recipe:
1 ingot of metal (using the same metal as above)
1 small mold
This will of course make crossbow crafting more difficult than it is now, but in my opinion wood crafting is one of the easiest crafts at all. Thus that would actually be a good thing as I see it. This would also account for the high prices on crossbows, which isn't that logical with the easy access to wood.
I would suggest a similar change to bow making, but the best idea for an altered recipe for bow making is adding "ordinary cams" (of the above metals) to all bows. This would not be completely logical but neither is the use of sandpaper (I think that bows have been produced for more than 10.000 years before sandpaper was invented) or the use of molds in weapon crafting (a weapon smith would have no use for a mold when he made iron weapons, except as an ashtray of course). So using this solution would make wood crafters more dependent on other crafts, as weapons smiths are depending on wood crafting and tinkering.
A second solution could be adding 2 different types of wood "ordinairy wood" and "bow quality wood" and you would have a chance of getting this high qualit wood when you cut trees. 20 % for hickory, 15 % for oak, 10 % for mahogony, and 5 % for yew. or just 5 % - 10 % for all types of wood.
