I'm having a little trouble picturing what you are describing. So it wont really be a take down because the limbs are fixed? Are you intending to splice the limbs together and glue on a riser? or were you picturing it to be like a 3 piece take down where each limb is attached only at each end of the riser. If that's the case, you'll need more than glue to hold it. I wouldn't recommend pine for the limbs unless you have nothing else to work with. Oak can be a good bow wood, what do you have access to? boards, staves?