Weapon of Earth - Pentacle, How to construct the earth pentacle Options

I'm building an earth pentacle to use in my rituals, but i have some doubts on its creation.

I'm building it around 6 inches, out of some wood boards i glued together.

I read in "Modern Magick" by "Kraig" that it is better to be concave, because this would direct the energy directly back to the one who sent it, in case of an attack.

I really don't agree to that, as i don't see how anything reflects back to its origin on something concave differently from something flat. I also don't understand why it has to be used against attacks, as it is obviously meant as a defensive weapon, or a shield. And a shield is definitely not concave, more the opposite.
It just doesn't add up, Kraig's theory, and it leaves me confused...

Could anyone give me some advise on this.
Also, the origin of the god names that are meant to go around it are not given in Kraig's book, I would like to know them to. (IMG:style_emoticons/default/huh.gif)

For the pentacle I would recommend that if concave doesn't seem right to you, no matter how many folks say concave don't do it (IMG:style_emoticons/default/smile.gif) I am not completely sure why some people use the concave version.
The concave bit is just one theory. The earth pentacle has many uses besides the obvious, (banishing a being from a possesed person being one of it's many uses), however a flat ones seems to work just as well. I have used both a flath one and a concave eath pentacle, and I couldn't really tell the difference.
Some schools of thought beleive that one should use a pentagram in the outer order for your pentacle, and a hexagram when you remake your tools in the inner order. Seems silly to me to remake it, so I just started with a hexagram.
Btw, Kraig did not intentionally put any blinds in his book. (I have heard the Modern magick is full of blinds theory quite a bit though) Well unless you count leaving off the letter on the air dagger (I think it was) then mention it later so that the student would pay more attention. Aside from that there are not any blinds. Some things in Kraig's book are a little different from other books, and here is the reason why. He has taught magick for many years, and before Modern Magick actually came out in book form it was a course he was teaching. He taught a lot of people with this course, and always asked them what worked for them and refined several things when he found that something worked better for the majority of his students.
Now there is also the odd chance he could have screwed up here and there while writing or editing the book, it does happen (IMG:style_emoticons/default/smile.gif)
Modern Magick was the first book on magick that I picked up, and fortunatly as well, there were a lot of very lame books around at that time as well from what I hear lol.
Athena
www.nightshademagic.com