,Anyone out there know of any good sites I can be directed to for patterns 4 horse armor.thanks 

Have you asked over at armourarchive.org   a group of forums dedicated to armor making---note they do use the british spelling in the name!

Hey Thomas powers I appreciate this.

You'll see me in both places.   And like making swords: experience making smaller stuff--human armor, will help a lot when you want to scale up to horses.

Training a horse to wear it is another issue...

12 hours ago, ThomasPowers said:

Training a horse to wear it is another issue

I'll bet it will be an issue, sure would have been with any I've owned in the past.  I threw a harness on a pony mare once who was supposedly green broke to harness, Yuh it took us an hour to catch her and 2 days  to find most the harness pieces. 

She is very used to the armor just need new stuff 

Amazing what blanketing and unblanketing a horse every day during cold spells will do...

Or, just not throw harness on green broke horse.