Pre-Treatment, before priming exerior wood
Post new topic   Reply to topic
Historic HomeWorks Forum Forum Index -> Paints & Finishes Goto page Previous  1, 2, 3  Next 
View previous topic :: View next topic  
Author Message
mateo



Joined: 02 Oct 2007
Posts: 41

PostPosted: Sun Aug 04, 2013 9:14 am    Post subject: Oil or acrylic primer if pre treatment is fully cured Reply with quote

Hi,

I have four bottom window sashes that were in fairly bad shape that I stripped and then pre treated with turp & penetrol. I was waiting for the magic 80% cured time to coat them with BM penetrating oil primer and I had to leave my house unexpectedly....unfortunately, they are now fully cured.
So... If I use a penetrating oil primer, it seems that it will not be able to penetrate into the wood. Am I better off at this point using acrylic? Or what will give me the best adhesion?

Thanks for any advice!
Back to top
View user's profile Send private message
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2980
Location: Portland, Maine, USA

PostPosted: Sun Aug 04, 2013 9:28 am    Post subject: Reply with quote

If the pre-treated wood surface is matte (non-reflective) then the wood surface is probably still porous enough to get some good mechanical keying.

If the surface is glossy (reflective) most of the open cells at the surface of the wood have been filled. I would buff off the gloss with coarse steel wool or sandpaper, clean thoroughly by vacuum and tack cloth.

In both cases I would proceed with a penetrating slow-dry oil-based linseed oil primer. Remember, the penetrating feature still gives you an advantage at all those sash joints where it penetrates into the joints and helps seal them.

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
mateo



Joined: 02 Oct 2007
Posts: 41

PostPosted: Sun Aug 04, 2013 9:54 am    Post subject: Reply with quote

Thank you so much for your reply John!

I will take a look and use my slow penetrating oil primer..... Thanks so much for all the valuable info. I've learned so much and my old house thanks you too!
Back to top
View user's profile Send private message
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2980
Location: Portland, Maine, USA

PostPosted: Sun Aug 04, 2013 10:08 am    Post subject: Reply with quote

You and your old house are welcome!

Please keep us posted on your progress.

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2980
Location: Portland, Maine, USA

PostPosted: Tue Oct 08, 2013 10:36 am    Post subject: Reply with quote

See the Pre-Treatment discussion here:

http://historichomeworks.com/forum/viewtopic.php?p=6257#6257

I started developing these pre-treatment methods back in the 1980s,
based on studies at the Forest Products Laboratory and my own experience.

If the paint is lifting off down to bare wood the main cause is
excessive moisture in the wood. The source of the moisture may be from
inside the house, or from rain water seeping in through joints in the
woodwork, or through cracks in the paint film.

Extreme Prep:
If the existing paint film is thicker than .015" (a dime is .023"
thick), then it is thick enough that the water vapor cannot easily
escape from the wood directly through the paint film, so it simply
pushes the paint film off the wood on its way out. When we want to get
the maximum durability of the new paint coating we remove all the
existing paint down to bare wood. We also clean the wood with a Wet
Abrasive Scrub:

http://historichomeworks.com/forum/viewtopic.php?t=1751

Durability:
With the combination of 1. Removal of heavy paint buildup, 2. Wet
Abrasive Scrub, and 3. Pre-Treatment, plus experienced and skilled
workers we have been able to get 20 to 30 years of life out of a paint
job. With an extreme salt water micro-climate that drops down to 15 to
20 years.

Sealing the Wood:
>>It seems to me that sealing the wood would reduce the opportunity for
the primer to soak into he wood for more "bite."<<

An effective pre-treatment should not seal the wood. It should leave
most of the wood cells at the surface open so the primer can still make
a mechanical bond by soaking into the cells. About 40% of the bonding is
mechanical and 60% of the bonding is chemical. The pre-treatment
improved chemical bonding by making the highly variable surface
conditions of old wood more consistent and suitable for better
performance of the primer.

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2980
Location: Portland, Maine, USA

PostPosted: Fri Oct 11, 2013 8:36 am    Post subject: Reply with quote

Forest Products Laboratory Water Repellant Preservative Recipe

As with any other time you mix various potentially hazardous or flammable materials, take precautions and ventilate the area properly.

Mix together:

1 gal. Mineral spirits or Turpentine
1 cup Boiled Linseed Oil or Tung Oil
1.5 ounces Paraffin Wax
1 to 3 fluid oz Color Pigment ground in oil (if color is wanted and using as a wood treatment and no painting)

Shave the paraffin thin and pre-mixed in a cup of the turpentine and set on a sunny window sill and stirred daily until dissolved); Let your concoction age overnight before applying it to exterior wood and stir it well; the pigments will settle.

Zinc napthnate can be added as a mildewcide/fungicide at the rate of 2 to 5% by weight if using the mix as a pre-treatment before painting, or up to 10% if treating wood that will be left unpainted.

Always test any new method or material on a small sample area first. Typically this mix without pigment will darken gray weathered wood, and add a slight amber hue to new bright wood.

Here is a link to a more complete document on making and using this recipe, but it is not currently available (due to the federal shutdown!)
The original make-it-yourself recipe from Forest Products Lab:
www.fpl.fs.fed.us/documnts/fplrn/fplrn124.pdf

I have begun testing beeswax as a sustainable alternative to paraffin--no results yet.


Take care, work safe and keep in touch.

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
rmlogan



Joined: 03 Dec 2013
Posts: 11
Location: ASHEVILLE, NC

PostPosted: Fri Jan 10, 2014 9:10 pm    Post subject: Reply with quote

how has the beeswax worked as an alternative to paraffin? where can I get paraffin?
When pre-treating with this mix do you treat all surfaces of sash, i.e... rabbits, sliding edges, top?

Plan to use benjamin moore slow oil after pre-treatment, that is is if I pre-treat. This is a really great primer, which really penetrates well.

Any oil primers you prefer?

_________________
Working with residents in the historic Asheville neighborhoods to preserve the beauty and cratsmanship of their homes with integrity at very competitive rates.
Back to top
View user's profile Send private message
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2980
Location: Portland, Maine, USA

PostPosted: Sat Jan 11, 2014 11:48 am    Post subject: Reply with quote

Quote:
how has the beeswax worked as an alternative to paraffin? where can I get paraffin?


Just did the first tests last fall. Mixing and application went well. No result yet on performance.

Quote:
When pre-treating with this mix do you treat all surfaces of sash, i.e... rabbits, sliding edges, top?


See Step 9a in the first message in this discussion:
http://historichomeworks.com/forum/viewtopic.php?t=955
and also the glazing and painting section of the Save America's Windows book:
http://www.historichomeworks.com/hhw/reports/reports.htm#Windows

Quote:
Any oil primers you prefer?


Any oil-based alkyd resin or linseed oil primer should work as long as it is compatible with the topcoats that will be used.
The standard in my shop is California's Fast Dry or Slow Dry Trouble Shooter Primer with California's 2010 100% Acrylic house paint or exterior enamel. I sometime depart from this standard to meet specific needs.

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
rmlogan



Joined: 03 Dec 2013
Posts: 11
Location: ASHEVILLE, NC

PostPosted: Mon Jan 13, 2014 11:56 am    Post subject: Zinc napthnate Reply with quote

Where can Zinc napthnate be found for use in the pretreatment mixture?
_________________
Working with residents in the historic Asheville neighborhoods to preserve the beauty and cratsmanship of their homes with integrity at very competitive rates.
Back to top
View user's profile Send private message
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2980
Location: Portland, Maine, USA

PostPosted: Sat Jan 18, 2014 8:46 pm    Post subject: Reply with quote

The EPA closed down the one major manufacturer of napthnetic oils in 2011, which was the common source of zinc napthenate for preservative products.

Here is one potential source:

Zinc Napthenate concentrate is available from Strem Chemicals Inc.:
Zinc naphthenate, 65% in mineral spirits (10% Zn)
http://www.strem.com/catalog/v/93-3037/84/zinc_12001-85-3
This is a concentrated chemical solution, not a consumer product. You have to know how to handle, mix and use chemicals safely.



Here is a Zinc Napthenate pre-treatment product made in Canada by RecoChem Inc.:

Clear Wood Preservative
Clear Wood Preservative provides protection against rot and mildew on above ground exterior lumber. It is a clear, paintable wood preservative containing 2% Zinc from Zinc Naphthenate, designed for projects where no colour change is needed or projects that will be stained or painted. Use wood preservative on outdoor furniture, fences, decks, sashes, doors and millwork.
http://www.recochem.com/en/products/wood_preservatives/clear_wood_preservative/item/clear_wood_preservative/
I don't know if they ship to the USA.

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Clueless Boomer



Joined: 13 Dec 2013
Posts: 4

PostPosted: Mon Apr 14, 2014 1:29 pm    Post subject: Pre-treatment before applying primer Reply with quote

I've been searching your forum on the subject of water-repellent preservatives and pre-treatment regimens for use on a brand new custom cedar carriage house door I scored on craigslist.

I've been using Wolman's Classic Woodlife WRP for 3 or 4 years on siding and trim that I've stripped down to raw wood in restoring my own 1860-era home. I doubt that this timeframe is long enough to confirm mildew prevention, so I’m not certain that Woodlife is my real solution. Since a waterborne product also raises the grain somewhat, it’s not ideal.

I tracked down a forum reference to California Storm Stain Penetrating Wood Stabilizer (now sold as California Storm System Wood Life Extender,) and I thought its new specifications & MSDS identified it as a mineral-oil based zinc naphtenate. Thanks for pointing out what I had missed––that it’s actually an oil/water colloidal suspension. Since your pretreatment protocol, developed over years of experience, favors oil-based products, I'm seeking such a system. For my own peace of mind, I'd prefer a pre-treatment from one manufacturer’s system of compatible oil-base WRP + oil stain primer + solid stain topcoat. Can you suggest a manufacturer that offers such a system? Or am I forced into alchemy of my own WRP according to your modified Forest Products Lab formula?

Now, as to my game plan: since my carriage house door is constructed in an overhead format, all its vertical v-groove T&G planks and border trim boards expose end grain all along the top and bottom of each panel. I plan to use Abatron Liquid Wood epoxy selectively as a sealer on all exposed end grain to prevent deterioration of the finish from capillary-action rainwater absorption. Since this door faces a north exposure, I hope to prevent future mildew by following with an overall coat of WRP. Oil-base WRP should avoid raising the grain of the wood or swelling and bowing its T&G planks along each 8’ x 2’ panel, which a water-borne WRP might. I’m told that to avoid tannin bleed-through from the cedar, I’ll then need to apply a quick-dry oil-based primer prior to my oil-base solid stain topcoat . Do you forsee any other problems in my game plan?

John, I know you're reluctant to put yourself in the position of endorsing brands, and I respect your scrupulous non-commercial ethic. Trying to stay ahead of the ravages of time with a paint/stain system has been a lifelong challenge for all of us restorers––homeowners or professionals––throughout history. You’d think a manufacturer or two would solve the science and cash in on our band of loyal followers and word-of-mouth.

Thanks again for hosting this priceless forum and its valuable exchanges.

Steve F
Back to top
View user's profile Send private message
Clueless Boomer



Joined: 13 Dec 2013
Posts: 4

PostPosted: Tue Apr 22, 2014 2:24 pm    Post subject: Searching for a Water Repellent Preservative Reply with quote

In my continued search for an oil-based WRP, some options are vanishing, but one new possibility emerges. RecoChem Clear Wood Preservative in the second post above seems only to be available for purchase within Canada, and not even offered for shipping to addresses in the United States.

But my google search for water repellent wood preservative yielded hope in a General Services Administration historic preservation technical procedure “Applying Water Repellent Preservative to Wood.” In addition to the USDA ForestProduct Laboratory formula for a WRP that John referenced earlier in this thread, this GSA document lists "X-100 Natural Seal," made by American Building Restoration Chemicals, Inc. A search of the ABR website turned up an oil-based pre-treatment that contains 10% copper naphthenate, called X-100 Natural Seal Pre-Finish, as well as other compatible oil-base semi-solid stains. In response to my proposed WRP/oil primer/solid stain topcoat plan, the helpful technical rep e-mailed a Forest Products Laboratories specification for its restoration of its own Madison, WI facility. The 2004 FPL specification mirrored my plan, with the exception of specifying 2 top-coats of acrylic latex stain (as opposed to my leanings to an oil-base solid stain.)

This ABR pre-treatment product could offer the lynchpin step in a system to prevent water penetration and mold/mildew deterioration in my carriage house door coating. Do you, John, or anyone else have any experience with this restoration specialty company or its products, or any input on my protocol? Is copper naphthenate equally (or more?) effective as zinc naphthenate in preventing fungus? I would appreciate any further guidance anyone can offer on the subject.
Back to top
View user's profile Send private message
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2980
Location: Portland, Maine, USA

PostPosted: Sun Jan 18, 2015 2:21 pm    Post subject: mold treatments Reply with quote

A common treatment for wood that has mildew and mold is household bleach. Typically it is mixed with water, 4 parts water and 1 part household bleach.

If using household bleach, rinse thoroughly with plain water soaking into the surface and joints and flowing off all surfaces to carry away residues. I have been using this treatment for decades with good results on exterior woodwork and window parts. Ten years ago I placed some tests comparing this treatment with peroxide treatment and heat treatment. Testing was done on exterior clapboard siding and windows. This past year I've gotten some results.

Bleach and peroxide treatments can result in loss of primer adhesion in some situations, especially when not rinsed well. They are effective at treating the insides of joints because they soak into the joints, which can be important if mold is present inside the joints. These wet treatments, especially with effective water rinsing and drying can take days to implement on woodwork with a lot of joints, like window sash.

Heat treatment to disinfect wood surfaces of mold growth can be very effective and take much less time. A typical treatment schedule is to raise the temperature of the wood to 140 F. for 20 to 40 minutes. This can be done in a dry-heat convection oven, but an infra-red lamp is more effective because the infra-red rays wiggle down into the wood (past the surface of the wood) to treat parts of the mold organism and mold spores that may be beneath the surface. Treatment times with infra-red are 5 to 10 minutes with a surface temp of 140F. With the oven method there is a risk of drying the wood and opening up surface checks related to medulary rays. This is much less pronounced with the infra-red lamp method.

Based on these results I am shifting my standard practice over to the infra-red heat treatment for extreme mold where it is practical. Your results may vary from my experience. I suggest you do your own testing before implementing.

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2980
Location: Portland, Maine, USA

PostPosted: Fri May 01, 2015 12:50 pm    Post subject: Reply with quote

Mildewcide paint additives may be effective as preservatives in the WRP recipes. Here are a few to consider. Always test your custom formulations in a small area before using full scale.

Brand, Product Name,
Ingredients with active listed first (% of product by weight),
Link to manufacturer's info

Rustoleum/Zinsser®, ADD-2™ Mildewcide,
2-(4-Thiazolyl)Benzimidazole (<55%)
Biocide Dispersion MIXTURE (<55%)
https://www.rustoleum.com/en/product-catalog/consumer-brands/zinsser/cleaners-and-mold-and-mildew-proof-paints/add-2-prevent-mildew-mildewcide-additive#tab-1

Sunnyside, M-1 Advanced Mildew Treatment,
3-iodo-2 propynyl butyl carbamate (20%)
Aliphatic alcohol Proprietary (30-50%)
Glycol ether Proprietary (30-50%)
http://www.sunnysidecorp.com/pdf/msds789.pdf

MX-3 Complete Mildewcide Paint Additive,
Carbamic acid, butyl-, 3-iodo-2-propynyl ester (20%)
http://www.cfiproducts.com/product-MX-3-Complete-Mildewcide.html
http://www.cfiproducts.com/pdf/MX-3-Comp-Mildewcide-MSDS.pdf

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
bjwhite



Joined: 21 Aug 2013
Posts: 2
Location: Yarmouth, ME

PostPosted: Mon Jun 15, 2015 1:14 pm    Post subject: Reply with quote

Hi John:

I’m restoring old wooden shutters. I will use the Penetrol/Turpentine mixture to pre-treat areas of severely weathered / punky wood. I’ve removed the loose paint and sanded to bare wood the weathered areas but it’s simply not feasible to remove every bit of old paint on every shutter. What happens if the pre-treatment mixture gets on some of the painted areas? Will this cause adhesion issues with an oil based prime coat? (I'm using SW Acrylic Latex for the top coat). Of course I will try to prevent this from happening, but can this cause problems if it's not cleaned off?
Back to top
View user's profile Send private message
Display posts from previous:   
Historic HomeWorks Forum Forum Index -> Paints & Finishes Goto page Previous  1, 2, 3  Next 
Post new topic   Reply to topic All times are GMT - 5 Hours
Page 2 of 3

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum