Best softwood species to glass over

Making a crowned pilot roof cross beam, 1.5" wide by 1.8 high with 4" crown over 7'. What is a good wood species which will work well with poly resin and fiberglass? No loads above the roof, just want the resin to bond well. So strength not an issue, just bonding adhesion as poly is poor at that. Thinking of soft wood for weight, cost, and ease of working issues.

Thinking of pine, spruce, or east. fir/hem. Will shape, sand with 60 grit before a saturation coat of laminating resin (thinned with 5% styrene) and fabric.

Thanks

 

Douglas fir is excellent for such work. Hemlock and spruce have also served well to receive the treatment. I would avoid heavy resin soaked wood.

 

Pine and spruce get good adhesion.

 

I laminated 2 pieces of 3/4 marine ply with epoxy for my rafters, pretty close to your dimensions. Zero flex in my roof. I'm a little late to the party, but maybe it will help someone out. I have glassed over tons of doug fir, but something to keep in mind is tight grain. Any water intrusion into the pulp wood that is mostly for sale now will expand the wood and split the glass.

 

Pauloni is excellent to glass in epoxy . I glassed a 23 ft paulonia strip racing hull with 8 oz carbon fibre with 6 oz glass over the crabon. Just make sure theres no gaps where air can cause bubbles.
Gaza