The Armour Archive

I recently purchased helm pieces from Ron Simmons (who's quality and speed of delivery I do not have espouse on this board).
Now I have done armor of most kinds, out of Leather, barrel plastic (not happy about it but it was a favor) kydex and steel.
However I have never made a helm before.
Because the top is in two pieces I am going to try to construct it in a roman ridge helm style. Any examples, ideas or advice would be helpful.
Thanks

These people have an exploded diagram on their page.
www.arthurian.freeuk.com

Also, check out the photos (late Roman stuff) at www.albionarmorers.com

Thanks
The UK site was good.
Some good pics and ideas.