Finishing

SPITZ · March 08, 2020, 04:24:11 PM

Hello. First post on this forum. Looks like a great spot. I'm sure this has been talked about before but I'm wondering what to finish my beans with. Pine logs were cut and in milled 2 size 3 days ago. Will have all joinery done within the next week. Would like to finish before raising. Looking for best finish options. Thanks

Don P · March 10, 2020, 03:46:29 PM

Hey SPITZ, being dead green and at this stage of construction I'd lean towards boiled (not raw) linseed oil. It'll help keep things cleaner, easily repaired and compatible with most oil finishes later.

rjwoelk · March 10, 2020, 08:57:35 PM

Make sure you are careful about the rags as they can spontaneous combust

SPITZ · March 13, 2020, 02:11:31 PM

Thanks guys. Much appreciated. I'm noticing up here in Canada there's a lot of double boiled linseed oil for sale. Is that appropriate? I also noticed that in the double boiled linseed oil it contains dryers. Any advice on this product would be appreciated.

doc henderson · March 13, 2020, 02:15:01 PM

raw linseed oil will stay sticky for a long time. my understanding is "boiled" does not mean with heat, but dryers are added. double boiled, I do not know, unless it has two drying agents.

Don P · March 13, 2020, 03:13:58 PM

From my understanding "boiling", either by heat or by mixing in various drying chemicals starts the polymerization process of the oil. My pure guess is that double boiling means they've done both. We did what I think is similar back in the day, Dad would get boiled linseed oil and a can of japan dryer and we would mix some of the dryer, which I think is cobalt in a solvent, to it to help it dry in the hot-humid southeast. Raw linseed oil would invariably attract dirt and debris, mold, and turn into a sticky black mess, exactly the opposite of what we were after. If "pure" is the goal you can find just boiled, as in heated, oil.

doc henderson · March 13, 2020, 10:44:28 PM

the drying agents are usually metals, in the old days it was lead and they heated the linseed oil to help disperse the meatal. raw oil is edible, "boiled" is poisonous due to the metal ingredients. raw is like vegetable oil and can go rancid. oil with the dryers (boiled) will polymerize and become a solid. I do not know what double means in this context. @GeneWengert-WoodDoc

D L Bahler · March 13, 2020, 11:22:18 PM

Raw is edible -flaxseed oil being the same thing.
Cobalt is dangerous stuff, and seems to still be the most common drying agent. Looks like your common off the shelf oils have salts of cobalt and manganese in them. Which means, they're highly toxic.

Also the drying agents is why you need to dispose of oil soaked rags carefully, or else they might burst into flames. There is an ongoing chemical reaction when exposed to oxygen that generates a lot of heat.

According to Wikipedia, oil that's only heated is "stand oil" and "boiled" implies the addition of metal dryers, the terminology going back to the medieval practice of boiling lead oxide into it.

Don P · March 14, 2020, 09:24:36 AM

This is what I enjoy about forums, more eyes and input expand what I think I know. Doing a little more digging it looks like "double boiled" simply means twice the dryers. There are companies selling boiled by heating alone or Heritage has one they refer to as "aged linseed oil" which supposedly hastens the drying, I assume it has already begun to polymerize. Interesting in their comments they said they source their flaxseed to be low protein which results in less yellowing over time, makes sense.

Back to the op, what I was looking for in response to the question is this. The wood is green (not great for drying the finish to begin with and BLO is going to have more issues here!) So anyway, a cheap, sacrificial prefinish that will help keep the timbers clean. From my experience I've also found that any "breathable" finish, even if short lived, on green timbers helps slow rapid surface drying and there is less checking. The finish, being applied to green wood, is pretty much sacrificial. In the early 90's Flood made a product called Seasonite which was a water thin clear petroleum stinky oil that went on easy and really did a good job in that regard. I haven't seen it in years, guessing a VOC problem. This isn't a food safe application so "toxic" has a different meaning to me in this regard but everyone has their own ideas there. The MSDS on whatever product is always good to review. Reboot, BLO might not be the best solution to the problem. For myself it is one I have used and have no problems with, what are others you have used in this situation?, Cheap, broadly compatible, clean and water repellant. Penetrol has intrigued me but I haven't tried it here, others?

SPITZ · March 14, 2020, 03:17:51 PM

Well I just applied boiled linseed oil mixed 2/3 linseed oil 1/3 turpentine. Looks pretty good and seems to be drying fine.

Another question.... We're going to raise the unit next week and I would like to apply tongue and groove pine to the top of the Timbers. Should I use kiln dried t&g Pine or should I get green Lumber to match the Timbers I just put up?

Don P · March 14, 2020, 05:16:09 PM

Dry, you don't want it detongueing, (is that a word :D), as it dries. I remember going into a model log home one time and looking up at the gaps and the plastic and insulation above, not what they had envisioned I imagine.

SPITZ · March 14, 2020, 05:39:22 PM

Ya. I figured.

I used the linseed oil as a temporary protective coating during construction. Does anyone known if I can apply cabot Australian timber oil over top after construction is done and everything has dried?

Don P · March 14, 2020, 07:16:45 PM

I'm about certain you can but give them a call.

SPITZ · March 15, 2020, 11:04:25 AM

I just contact the manufacturer and they are suggesting I need to strip the linseed oil. I'm pretty sure they may just be covering their butt. Does anybody have any suggestions on how to put a stain type finish on top of linseed oil that already exists. Any help would be appreciated. In only applied one coat.

doc henderson · March 15, 2020, 01:02:42 PM

I would go with an oil based finish. is this boiled or raw linseed oil you put on. is it still tacky? it soaks in so not sure how you could strip it. they usually recommend to wait 72 hours before applying a top coat surface finish. I have put minwax spar urethane over oil like Danish oil ect. when you say stain type finish, do you mean a top coat, or are you wanting to change the color or bring out the grain? I think you can still apply a stain for color (oil based) and then a oil surface finish.
ps: I looked back and it was boiled. you should be ok. try some of the oil you are talking about. it prob. has linseed oil in it as a primary ingredient.

doc henderson · March 15, 2020, 01:10:21 PM

It has Tung oil in it. A lot of fancy finishes are mostly all made from the same stuff. sounds like yours can come with a tinting. I would pick one and try it.

SPITZ · May 01, 2020, 02:51:58 PM

Hey guys. Timber install was delayed with all that's going on. One coat of 2/3 linseed oil to 1/3 turpentine was applied to the green timbers 9 weeks ago. I am wondering if I did 2 more coats of the same and added oil based stain to the mix for color. Any thoughts?

Don P · May 01, 2020, 06:06:37 PM

Sounds fine, hopefully you've got it under cover somewhere. This too shall pass... sometime.

SPITZ · May 02, 2020, 09:37:20 AM

Yes. Stored indoors. I figured I could add some stain to the second coat just looking for input as I have never done it before and am a little nervous to do so.

Don P · May 02, 2020, 01:09:22 PM

You can also find universal tints at a paint store but generally with that kind of mixing try a little sample batch and if they are incompatible it'll show up right there as you try to mix.

SPITZ · May 02, 2020, 03:41:16 PM

I tried mixing linseed oil, turpentine, and minwax stain. Seemed good to me. Any advice on mixing ratios?

doc henderson · May 02, 2020, 03:52:37 PM

glad you are moving forward. the key is to find the color you want, and keep track of the "formula".

Brad_bb · May 03, 2020, 11:05:39 PM

The big thing for green wood is that you don't seal the surface. It must be allowed to continue to dry. Most timberframers I know (me included) use Heritage natural finishes. The regular indoor version contains flax (linseed) oil along with tung oil and some other ingredients like bees wax and pine rosin. This finish does not seal the surface but allows the timbers to continue to dry. It does dry as well, and will not be tacky.

Don P · May 04, 2020, 08:47:53 AM

Basically very similar, I've used Heritage/ Landark and have no issues with it. The terpene in Heritage is citrus oil. The other constituents are in low enough concentration to not appear in the msds.

That is a good point about over applying finish before the wood dries. It is good to slow surface drying to help reduce checking but building to the point of a solid film over green wood is not a good thing.