Knotholes

Got the answer on this one

I asked the same question a few months ago. I had a few e-mails back and forth with a forum member here who does restoration work in Canada.

Now listen up, I tried the following for outside Pine knots.

1) Amber Shellac--Zinsser

2) Cover Stain--Zinseer

3) Tite Bond III Brown Carpenter's Glue--that's right glue

I tested areas with each product. As my Canadian contact said, the exterior brown carpenter's glue sealed the knots efficiently without bleed through. I applied one medium coat of Cabot's Provt Exterior Latex Stain over the primed test areas.

Results: Cover Stain bled through and was unacceptable

Amber Shellac--straight out of the can-- slight bleed

Tite-Bond--Best coverage, no bleed through

As explained to me--the glue will expand and contract with weather conditions. Shellac and other materials are more brittle, thus they will crack rather than give allowing the tannins to seep through the primer.

BTW--The glue goes on with a throw away 1 inch. Spreads in a similar way to any primer. Do not cut. Hope this helps.

I am doing a large barn restoration job this year and this tip really will make my life easier. First, I'll hand prime with the glue--then finish up with two coats ProVT via spray.

I did not use the BIN because I was lazy and figured the Amber Shellac should do pretty much the same thing. I use BIN for other purposes, and it might be fine. But, I think you will be more pleased with the lasting result of the brown glue.

JTP

vermontpainter said:

Its a bad scene. Everything about that deal is wrong. Bad looking wood. Should have been installed with the BIN work done and preprimed for two obvious reasons. The painter could do that alot more efficiently and ergonomically on sawhorses. And being tongue and groove, as the wood expands and contracts there is the risk of seeing where the painter couldnt get. Ceilings like that are nutbusters. I'd budget in several trips to the chiropractor.

Click to expand...

Ayep!

"Z paint bin shellac and lay it on heavy because with that many knots i see flashing in the future...i would try to convince them it would look bad painted no matter what and have u seal it..lol"

tried

"Rich John would use me....and I'd do it too! I like this kind of stuff.
Like a working vacation in Utah?"

Thanks guys, It's going to be a lot of work for me and my guys. The HO is very nice and specific about what she wants and willing to pay for it.
I am still debating on what to fill the holes with. She wants a smooth look.
Looks like I have to learn how to do multiple quotes!

I see now
This homeowner made a few big big mistakes
(at least I can't for the life of me think of why they did them on purpose)

They went with the cheaper wood (lower grade, more knots and holes) thinking they'd save money because it was "...just being painted anyway"
This is not true, as the labor and product to properly paint this is way more than if it were "clear" wood

They installed it before having it shellacked, filled, primed, and first coated, thus adding even more labor to the bill...lots more labor...and PITA labor too

That being said, I'd fill it, sand it, BIN it, re-fill it (the spots that need it), prime it, paint it
Obviously it's not going to be as easy as that sentence makes it sound

The fill and sand is going to be tough, being upside down and all
As much as I like Elmer wood filler, it will sag horribly when up-side down
I'd try Minwax Wood Filler, that tends to cling better
Works well in odd upside down spots where Elmer's sags
But I've never had to use so much upside before
Might want to try a few spots first just to make sure
You just don't want t e using a two-part epoxy on this thing if you don;t have to (time consuming and over-kill for the non-structural fill job)

The re-fill after the BIN, I'm just assuming it will need some to be nice and flat
Depending on how it comes out, spackle or joint compound may be an option
Maybe you won't need this, but I'd plan for it in the bid/time estimate anyway