That which is called "1-1/2" Schedule 40 PVC pipe" actually has an ID of 1.610" and an OD 1.900" (according to McMaster-Carr). The holes that are specified in the drawing are 1-7/8" which is 1.875" in decimal. This means that if everything were perfect, the PVC would not go into the holes at all. On the drawing for the mobile goal (
http://www2.usfirst.org/2004comp/200...veableGoal.pdf ) the words "Dress to fit" refer to the holes in the wood. I think they intend that you ream the wood out until the too large PVC fits OK. I don't know why you are experiencing a 10 degree slant or even a little "wobble". Those poles ought to be skin tight. Confession: We have not actually built our goals yet (today, I hope), so maybe I'm missing something.