Pyramid bow and backing questions

[Enoughpancakes]

I'm working on my second bow (first one is a functioning red oak board bow, but I have no idea the weight it pulls) and I have some questions for you guys.  This is going to be a red oak board pyramid bow, hopefully pulling around 55# at 29-30".  The board I selected seems pretty good, but I was thinking about backing it to make sure I reach my desired weight.  My home depot carries some Maple boards and I though that might make a good backing.  So my questions are:

1. What type of Maple would a store like home depot carry?  Is it suitable as a backing?

2. Does the backing board have to be selected like the main red oak board?  Is grain just as important for the 1/8" or less backing?

3. Without a backing I was going to bring the limb thickness down to 1/2" and go from there.  If adding a 1/8" backing would that mean I bring the red oak to 3/8" so the total thickness (backing and main board) equals 1/2"?

4. Finally, my bow will go from 2" at the fades to 1/2" or 3/8" at the tips.  I have seen pyramid bows use post (pin?) type nocks, but would prefer to use the conventional style nocks (such as on the bow built here  http://georgeandjoni.home.comcast.net/~georgeandjoni/boardbowbuildalong.html  ).  Can I safely file these types of nocks even though the limbs are so narrow toward the tips?

[John Scifres]

1.  I have tried maple from Lowes as composite bow backing and was not impressed.  But if all you want to do is protect the back from raising a splinter, it should work.

2.  Yes.  Edge grain (quartersawn) is most likely to work and be findable at hardware stores.

3.  If it were me, I'd just glue it on the 1/2" and see what happens.

4.  1/2" is fine.  3/8" might be pushing it for side nocks and red oak.  I do it with osage and they are a bit scary.