Wood filler for outdoor service

[68bucks]

I'm not sure this is the best place for this post but her goes. I have a new porch on a barn. The ceiling is vinyl but the beam running around the perimeter and the posts are wood and I want to paint them white. The posts are 6x6 treated while the beam is (2) 2x10's sitting in notches in the 6x6 posts. Between the (2) 2x10's I ripped a 2x4 to fill the gap. While the 2x4 fits in real nice there is still an obvious joint there. I would like to fill it with something to make it look more like a solid piece of wood. I have tried caulk and it helps but it doesn't really fill the gap to my liking. I think I need something more like drywall compound that I could use a 4" drywall knife to apply then to smooth off. Its in an overhead position tucked in under the porch roof overhang a foot so water won't pour on it all the time. Any ideas what type of material I could use? As I said I want to paint over it in the end.

 

[user 4883]

Rip a 1x8 board to width, edge treatment if you like, prime it, nail it up, paint it & call it.

 

[Snoonyb]

Here is a product that will outlast you; The Most Trusted Name in Trim, Moulding and Fastening | AZEK Exteriors

 

[bud16415]

If you really want to just fill the gap and trowel it out sand and paint, you could use automotive body filler (bondo). It can even be thinned with fiberglass resin also sold at the auto part store. It is a two part system and you mix a hardener into it and then you have a short time to apply it.

 

[tomtheelder2020]

I had never heard Bondo could be thinned! Great tip!

 

[joecaption]

I'm 100% with Snoonb on this one.
I would have wrapped the beams and post with PVC so there was never any painting needed ever again.
The second way that was suggested if you just cover it it with a piece of 1X, it will look like all one piece, no sanding or mixing required.
If you did use Bondo there is no need to thin it, but you better work fast because it hardens really quick.

 

[Jeff Handy]

Home Depot sells similar pvc trim stuff from Veranda.
Easily cut or ripped to size, paintable or just leave as is, white.
You can get little bungs to hide your screw heads also.

 

[68bucks]

Thanks for the ideas. There are some uh, unusual trim details on the hose that the people that built it moled from bondo I guess. They look fine and are close to 30 years old. The house has a lot of porches and there are arches cut from 2x12 that span from post to post. I think I might use that look. I'll cut the arch and mount it down the middle then I could put a piece of cove molding up there and that will hide that seem. I do like the PVC idea for maintenance if I can figure a way to get the a look I like.