Painted board leaking pine pitch

[Anthony Whitesell]

The title says it all. Any suggestions?

I build a door frame for a bi-fold door and apparently one of the boards wasn't dried enough? It was primed and painted and is now oozing pine pitch.

[Danny Hamsley]

Pine has to be heated to set the pitch. For example, if it was heated to 130 degrees, then the pitch would be set and not ooze out unless the temperature exceeded 130 degrees. Do you have the means to give it a good heat treatment?

[Myk Rian]

I framed a garage window that seeped for 3 years.
Since it was in the garage, I didn't mess with it. A fly is trapped inside the drippings.
I'm saving it for the next Jurassic park.

[Anthony Whitesell]

Nah. Heating the bathroom to 130 isn't really an option.

[Dave Zellers]

Do you have the means to give it a good heat treatment?

Exactly. An old timers trick is to take a torch (propane, today) to it and bleed out all the pitch. Don't burn the wood, just get it hot enough to melt the pitch and then as it oozes out, scrape it off.

When the pitch is gone, problem solved.

[Lorne Steed]

Anthony; If you scrape off the bunched up resin and wipe with mineral spirits-dry completely with rag and then seal it with 2lb cut of shellac ( Zinsser Seal Coat is a good one ), you will then be able to re coat the substrate with your choice of top coats be it alkyd or acrylics. Any more questions -feel free to ask. Lorne Steed

[Anthony Whitesell]

I'm not so sure about using a torch, but I may try a good heat gun. Don't forget the board is installed and painted already. If I knew this ahead of time, I probably would have returned the board to the mill and asked what gives. I thought the kiln drying process would have set the pitch.

[Chip Lindley]

Next time you might try fir, redwood or western cedar instead of pine, if construction lumber is your only source for door material. If you can get poplar or soft maple, those would be even better!

[Dave Zellers]

I thought the kiln drying process would have set the pitch.
Not even close. Drying lumber is for moisture. Pitch can last for centuries.

[glenn bradley]

I'm with the shellac recomendation or Zinsser B.I.N. that is made to block such problems. The blocking agent? Shellac.

[Larry Edgerton]

Not even close. Drying lumber is for moisture. Pitch can last for centuries.

I suggest that you pick up a copy of the "USDA dry kiln operators manual" and read about setting the pitch. You are posting misinformation. If he has pitch running it is because it was not brought up to temp for a long enough period to set the pitch.

Anthony. When I run into one of these a solution I use is to drill a hole at the point where the pitch is exiting downward through the back of the jamb in this case, fill the face side of the hole, scuff, prime and repaint. The hole through the back is a path of less resistance and the pitch running out the back can never be seen.

[Anthony Whitesell]

Interesting suggestion. But a picture of swiss cheese enters my mind. It's oozing like a cold glass of iced tea sweats on a hot summers dry.

[Larry Edgerton]

Ahhh

You have some "Fatwood" in there. Most times its a small crack that leads it out, but it sounds like you have one of those translucent pieces in there. Thats a tough one, the area is so big. I never tried the torch thing, but this sounds like a good test, but keep in mind, that stuff will burn in a heartbeat. Your heatgun idea sounds better.

Take a piece of that stuff and hold a match to it. It lights in about a second. Its good for camping trips and lighting the fire in the fireplace, hence the "Fatwood" moniker. I cut it up into little sticks for camping.

[Lee Schierer]

Resins from pine will bleed through latex paint over time. If you don't care fore the visual knot effect, seal the wood before painting with shellac. This will prevent the resins from bleeding through your paint and will also help the paint adhere better.

[Anthony Whitesell]

It's not resin or knots bleeding. There is actual pine pitch leaking from the wood. If I remember, I'll take a pic to post.

[Lee Schierer]

It's not resin or knots bleeding. There is actual pine pitch leaking from the wood. If I remember, I'll take a pic to post.

Resin is a hydrocarbon secretion of many plants, particularly coniferous trees. Pine pitch is the resin.....

[Anthony Whitesell]

What I mean is that the knots of the wood are not producing a dark image in the coat of paint, but the pitch is being secreted through the surface of the wood and through the paint. Such that there are droplets of pine pitch on the surface of the door frame.

[Scott T Smith]

Let me preface my post by stating that I operate a kiln.

When drying pine in a low temperature (dehumidification) kiln, in addition to the normal cycles for drying, sterilization and conditioning, there is an additional cycle for setting the pitch. This is usually performed at the end of the kiln run.

Normally, in a DH kiln the drying temperature is less than 120F, and the sterilization temp is 135F or so. 160F or greater is recommended for setting the pitch, as this will cause it to crystallize as it cools and thus prevent seepage.

My personal observations are that there is around a 25 degree delta between the pitch setting point and where it will still secrete. Thus, if the pitch is set at 160F, the board may secrete pitch if the wood gets above 135F. Below 135, you're fine.

Construction lumber is typically dried in high temperature (conventional) kilns, so you will rarely see pitch seepage unless there were some issues with drying. Trim lumber may be dried in either a conventional or DH kiln.