I saw on net that if a metal baffle was put in front of filter bank
the baffle would reduce about 1/2 of paint overspray that would
normally go to filter material and therefore reduce cost of filter
disposal and cut amount of filters purchased.  But article did not say
how baffle should be built nor was there anyway to contact writer. 
Can anyone help me?

I couldn't find much, but this might give you some ideas:

http://www.hse.gov.uk/lau/lacs/71-3.htm

Look at Figure 8