Long time lurker on this forum. Have been admiring the amazing work
turned out by the membership here and decided to join.

I am looking to build a 904-4 fly rod for my son and would like to replicate
the awesome colors of the Sage TCX series rods.
I can mix colors and feel I can paint a blank with reasonable results, but due
to painting over a gray blank and transparency issues, I'm not sure I will get
the desired results.
Anybody ever done this color before?
Anyone have a automotive code for this?
All advise would be appreciated.

i would not paint a 4 wt fly blank
It will just add weight to it and slow the performance of it

Do some cheap blanks to get the hang of painting

Bill - willierods.com

Your best bet is to spend some time in an automotive paint store or auto body shop looking through paint code chip books from different manufacturers.
Pay attention to fine pearl colors. The metallics look too coarse for an accurate match to the sage

I have found that DupliColor Auto paint is very thin, durable and sets up quick
If you have some thing to match it with bring the cans out side to match color Most are metallic and shine nice in the sun

Bill - willierods.com

Thought!? Since it is from you for a son, it will be wonderfully unique the older it gets. Why not put the 'creative/personal' touch into it in your thread wrap colors, handle make up (Birch Bark, Burl,Checkers etc), perhaps a little feather inlay, angle wraps / trim wraps on the guides, unique butt piece. 30 years from now, it being a similar color to a Sage will mean zip in comparison to the personal touch and love put into it from 'Dad'! Enjoy

If you want a blank with a finish, you might check a couple of other manufacturers as well. St. Croix offers some very nice blanks with different finishes but less money than a Sage or other high end offerings. You can customize further with unique wraps and signatures to make it a very special gift for your son.

Good luck!

Terry