Linseed Oil Alternative after Application

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Permalink Reply by Kelly on December 28, 2008 at 5:51pm

Hi Rolly,

They used to recommend linseed oil but they do not now. However you can not apply any other stain over the linseed oil because it will not adhere. If you want to removed the mold and mildew I would recommend to powerwash the log home with 700 to 1500 psi. Pre wet the log first with water, then apply 1 gallon of bleach to 3 gals of water and apply from the bottom to the top. This way the bleach will not run or streak. Leave the solution on for 15 to 30 mins. then rinse from the top down with water making sure you rinse, rinse, rinse. Wait 3 to 4 drying days before reapply your stain. The bleach will kill mold and mildew. However if you do not want to use the bleach there are other cleaners out there. A cleaner and a brightner called (CPR) which will also clean the logs for you. You need to apply a stain with some UV protection. You need to protect the logs from the UV Ultra Violet Ray. If your happy with the linseed oil powerwash it and reapply the lindseed oil again. If you are not happy with the linseed oil then you would have to strip it or cob blast it off with ground up corn cob. There is a product that you can add to the stain called (StayClean) which prevents mold and mildew.


I hoped this helped!

Sincerely,

Kelly

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Permalink Reply by ChinkerBob on December 28, 2008 at 8:26pm

Thought I'd add to what Kelly advised, which was good information.

First, be very careful powerwashing any logs. If you get too close to the logs the force of the water coming out of the tip will tear up the wood and make it ugly. I used to do it a lot, and it is possible to do it right. Just keep the force of the water in mind as you do this. You will probably have to at least lightly sand the logs afterward because they will probably get a bit fuzzy. You shouldn't have to sand so much that you get rid of the handpeeled look. Make sure the log surface is very dry before you start sanding.

If you go the bleach method, it is best to use oxygenated bleach rather than chlorinated bleach, especially if you are going to use a modern, water based finish. Any unrinsed chlorinated bleach will attack the new finish and make it less effective. If you do use chlorinated bleach, you have to rinse until you can't smell it anymore, and that is rather difficult to do. You'll want to rinse oxygenated bleach well too, but you don't have to be quite so thorough.

Kelly's suggestion that you corn-cob blast the house is a good one. A bit spendy, but well worth the effort. It will clean off all (or at least most) of the staining you have now. You wouldn't have to do the powerwash thing too, just corn blast it. The one place where you may well have stains too deep in the wood to get rid of is in the log ends, if they have absorbed any of the color of the mold, etc. Though this comes up more often in vertical logs that sit in dirty water during the early, unroofed part of construction, you may have similar problems due to the mold. You will have to live with the discoloration if that is the case. I would suggest as dark a color as you can stand to help hid such staining if you have that problem.

Kelly didn't suggest it, but someone else might. So I'll say here that I advise against using oxalic acid to clean your logs. It works fine, but if you get it on too strong or don't rinse it off, it will attack any brown stain and can, if there is enough of it, actually fade it out completely. The acid attacks the iron in the red coloring (part of any brown stain) and apparently more or less dissolves it. The product can be used successfully, but I recommend against it just because I've seen a few too many horrible outcomes using it.

Heed Kelly's advise to use a mildicide in the finish. You are apparently in a moist area, and though you may well be concerned environmentally, putting a good water-based finish on your house (more environmental than oil anyway) with a good mildicide will mean that you have to do less work down the road. The usual method these days, at least in the northwest, is to spray a water based stain with the desired color, and then spray a clear coat over it. Then, depending on local conditions, spray another coat of clear on every two or three or four years to help protect the color coat.

Oh, the other downside of linseed oil is caulking adhesion. Your house is a full-scriber, so you are hoping you won't have to chink it. But you will probably have checks and other leaks that you might want to deal with vai caulking. It won't adhere well to linseed oiled surfaces.

I don't know what kind of wood you have used, but chances are as it dries up after being so wet, you will start getting opening in the cups and between the logs that you were hoping would not occur. But this additional wet/dry cycle will probably cause you at least some grief. You'll be better prepared to deal with it if you use a finish that is caulkable.

There are undoubtedly people here who swear that modern oil finishes are better than the water based ones. Its an old argument and I'm not quite sure who is right. As a chinker, I prefer the water based finishes because I can be certain that my product will adhere to the logs. And the water-based materials I am most familiar with work quite well when properly maintained. There are plenty of oil finishes that can be chinked and caulked over, so you do have a choice. However, though you can later put a water based finish over an older oil finish, you can't do it the other way around.

Given that Canada is about to prohibit oil based finishes, if you continue with the linseed oil you will have to stock up quite a bit, and then when you run out, you will have a heck of a time prepping the logs for some other sort of finish. With only one coat on right now, and the problems you are facing with the wet logs, it seems to make more sense to solve the problem now while the house is unoccupied and easy to clean both outside and in, rather than trying to figure out how to get rid of the linseed oil (especially on the interior) sometime down the road.

And one other thought. Though I generally recommend against this, its mostly because I work mostly in dry climates with few bugs or fungus problems, you may well want to use a borate treatment on the logs after you get them cleaned off. Depending on which product you use (glycol or water based, or borate rods), you have to keep things like the weather in mind as you apply it. But borates attack not only insects (the reason most people use them) but also attack fungi. And it looks like you do have fungi. So you might look into that option. I don't know enough to give you any useful advise. Hopefully someone else will have some ideas.

You have to use borates before you apply a finish, (except for the rods, which are inserted into holes drilled into the logs). So this is yet another thing for you to consider as you set about solving your problem.

Good luck with everything. Hope you have a dry spring so you can deal with the problem without having more rain attack your fixes.

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Permalink Reply by Rolly on December 29, 2008 at 5:32pm

Thank you so much for all the very valuable information. I just discovered this forum and I am glad that knowledgeable such as yourself are here to help me throughout my journey!

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Permalink Reply by See Dirt Run! Inc. on January 4, 2009 at 10:53am

Good morning! :)
Thought I would jump in and share here. First of all, if you have linseed oil on the logs and the product containing it has adequate mildewcide and antifungal in it, not a problem at all. And yes in theory you could put an acrylic or another oil over linseed oil because as it goes....acrylic over oil OK, Oil over acrylic NOT ok. It WILL adhere. However we never ever suggest this, and why we don't is simple. We have seen massive mildew failures in oil products containing linseed oil. It is VERY possible to go over a linseed oil application that doesn't look to the naked eye like it is problematic. But if you put an acrylic or any other coating over it, and you have moisture there (doesn't take much WMC for it to grow) well now you have the potential for a failure UNDERNEATH of a decent coating that is tough to remove.

If you want to switch to another product it is always suggested that you strip off the old finish via chemical stripping and washing or by blasting. Both methods yield excellent results when done properly and the washing and stripping when done properly does not do any more harm to the wood than blasting does, but there is a science to it.

There are different types of oils. Linseed oil based products DRY. This is important to know. Products that cure and dry can take subsequent applications over top of the initial application. It is the parafinic oil based products that do NOT dry, and are considered to be moisturizing in nature. There are also products that contain both, with the parafinic oil diving into the wood, and the drying oil curing closer to the surface. The pigment that is locked in close to the surface is what gives you the UV protection the logs need.

You can't strip off a finish with a percarbonate, you need a stripper designed for stripping based on the base of the finish you are removing. Oils and acrylics require a different approach to stripping and the chemicals involved are different. Percarbonates are meant for light duty maintenance cleaning and for killing mildew. All washing with an alkaline, percarbonate or more caustic products needs to be neutralized with an acid. Never skip this step. After washing always use a moisture meter to determine the WMC of the wood before applying a finish so you don't trap moisture in the logs. It's not a matter of a number of days, it's a matter of the percentage of moisture in the wood. Climates and seasons vary and so too do the drying times after washing.

Products that have the neutralizer built in (clean and brighten) are not worth it, and are a waste of money. Get two distinct products and use each in turn. Your results will be far better. And lastly but most importantly, use the PPE required for the kind of work you are doing. You can end up with nasty chemical burns to your skin and lungs, or if blasting a nasty respiratory infection. Always be safe.....

Beth
See Dirt Run!

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Permalink Reply by Greg SWEETS on January 6, 2009 at 12:35pm

hello,perma chink systems has 2 products to clean the logs wood renew and log wash
you can go to www.permachink.com and read about it or call my distributor in canada
at 800-746-7773 ask for sandy,they send out samples of wood renew.I would not use
bleach on any log cabins and destroys the fibers in the wood and also can cause
adhesion problems.if you need to contact me I am at 800-548-3554

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