Timber Framers Guild

Avoiding sap stain in white pine

Posted By: gkautzer

Avoiding sap stain in white pine - 05/05/02 02:03 PM

I had planned to build a timber frame next spring with logs that would be cut in December 2002. However, a neighbor has decided to cut a stand of white pine in late May this year to make room for farm expansion. I can buy these logs reasonably. I wonder if I should get these logs because I can't start working on cutting joinery till fall. I want to prevent insect damage and sap stain to the extent possible. I have a Woodmizer sawmill. If I slab off all the bark and stack the timbers under metal cover sheets with two inch stickers in a shaded area, will I be able to avoid the sap stain? Will the there be any problem cutting joinery in pine that has dried for 3 months? Is there any treatment, chemical that I can app;ly to prevent the sap stain? As timber framing is a new adventure for me, I invite your comments and advice .
Posted By: Mark L Surnoskie

Re: Avoiding sap stain in white pine - 05/16/02 04:46 PM

I had planned to build a timber frame next spring with logs that would be cut in December 2002. However, a neighbor has decided to cut a stand of white pine in late May this year to make room for farm expansion. I can buy these logs reasonably. I wonder if I should get these logs because I can't start working on cutting joinery till fall. I want to prevent insect damage and sap stain to the extent possible. I have a Woodmizer sawmill. If I slab off all the bark and stack the timbers under metal cover sheets with two inch stickers in a shaded area, will I be able to avoid the sap stain? Will the there be any problem cutting joinery in pine that has dried for 3 months? Is there any treatment, chemical that I can app;ly to prevent the sap stain? As timber framing is a new adventure for me, I invite your comments and advice .
--------------------------------------------------------------------------------
Your piling and stickering should prevent mold if there is enough air movement. Sapwood is what the fungi that causes blue mold thrives on because of the carbohydrates stored in the cells. Growth stops below 40*F and above 105*F. Oxygen deficiency stops it and moisture content below 20 % or above the saturation point also stop it. The best way to control it is chemically inhibiting the fungi. Borate salts (Borax) kills the fungi. A borax and water solution sprayed on will prevent the staining. You can also buy commercial sprays (yardguard, timbor etc.) Borax solution will also keep the bugs out. As for the cutting, it won't be that much more difficult because the muisture will still be pretty high. I would also endseal the timbers to slow the checking. Hope this helps.
Mark Surnoskie
Posted By: northern hewer

Re: Avoiding sap stain in white pine - 05/18/02 01:35 AM

Hello All:
Just a note from my experiences, there is a possibility that if you cut and pile the squared timber like you suggested with stickers, you may notice a dark streak across the timber where each sticker lays. Now maybe you can remove this, but it may go down in quite deep, and you may have to remove an inch or more of material to remove the dark streak--I am suggesting cutting alittle oversize so that you can freshen up the surface just before construction starts. We used this technique to remove a bit with broadaxes to put on a new hewn surface to speed up and meet deadlines of raising bees.
Another idea is to strip the bark off, and let the outside dry somewhat That will help to keep out the pine worms, or if you have a small pond close by float the timbers, and that will keep out the little creatures, and the eventual timber will be of good quality, but will have a high moisture content, but no check marks or cracks. This is a trick used by the oldtimers, and they always said that materials cut from logs floated in the water was far superior to land dried logs.
Maybe someone would like to comment on any of these sugestions,

NH
Posted By: gkautzer

Re: Avoiding sap stain in white pine - 05/20/02 02:50 AM

Thank you Mark and NH for your replies to my questions. I received some further info from a chemist who works with wood preservatives at the Forest Products Research Lab in Madison WI. He suggests a homebrew concoction which will provide temporary protection against fungal growth. It is prepared by making a saturated solution of 20 Mule Team borax and adding a pint (cost about $10.00 at Menards) of home humidifier water treatment which contains quaternary ammonium . The borax is added to 5 gallons of hot water until no more will dissolve, and then the humidifier chemical is them added. The mixture is then sprayed or brushed on. The chemist said that some fungal staining organisms are not inhibited by borax and thus the addition of quaternary ammonium.
He also suggested a commercial product used in sawmills called Kopcoat NP-1. A sawmill near me uses this in a diptank to treat pine lumber. It is also used to treat logs which are sent overseas in the holds of ships. The cost is aboput $50.00 per gallon but it is used in dilution of 1 to 100, so 1 gal of concentrate makes 100 gallons of mixture. It contains borax and an iodine salt and does not stain the wood. One problem is that the smallest quantity sold by the manufacturer is 5 gallon pails. I am going to buy a gallon of concentrate from the local sawmill er who gets it in drums.
NH, I will be slabbing the logs in the first cutting and they will be re sawn to final dimensions later, so I shouldn't have sticker marks. Would like to throw them in a pond but don't have one close by.
I looked up yardguard and it appears to do the same thing as Kopcoat but is considerably more expensive.
Fortunately the wet weather here in WI has delayed cutting of the trees but I will still need to apply a treatment.
Posted By: John Milburn

Re: Avoiding sap stain in white pine - 05/21/02 01:29 AM

gkeutzer, I was once told by and old sawer that if you use kiln dried stickers you are less prone to get stain or mold under the stickers. Perhaps a little of your homemade antifungal/stain brew at the stickers might help. Any coments? john..
Posted By: gkautzer

Re: Avoiding sap stain in white pine - 05/29/02 11:44 PM

John, yes I agree that it is best to use very dry stickers and I always do with my lumber stacks. I think your suggestion to use the fungicide at the stickers is a good one. Thanks for your ideas. Gene
© 2024 Timber Frame Forums