McCloskey's Man O War is very good, and is now my go-to outdoor varnish....but why would you mix it with anything, it's good right out of the can. It should hold up for the 2-3 years period you want for a recoat. I have a redwood bench that's outside all the time and catches afternoon sun, it's still good after 5 years (this is Ohio, not nearly as harsh as your weather). But better than the McCloskey's would be a true marine spar, like Epifanes (there are several, that's the name I can remember at the moment). Check with a marine supplier for the choices. For me, none of the other choices would even be on the list.

 

The finishing companies spend thousands of dollars on chemistry research and development. Some turn out to be very good for what they were designed for. Some, not-so-good. (Helmsman, for example).
When someone asks me for advice, I steer them towards the more expensive products. THIS is where most problems start. Folks on a tight budget, building with Box-Store materials, using the cheapest finish, and wanting a 10 year (or more) warranty for minimum maintenance, no yellowing, no flaking, no nothing........
It just ain't gonna happen, folks.
You get what you pay for: Helmsman for $8.00 a quart or Interlux Sikkens Cetol Marine Wood Finish for $50.00 a quart.
You have your options - the rest is up to you.
Please keep us in the loop as to how you proceed.

 

I took a finishing course from Bob Flexner in the early 2000s. Since you mentioned him, you probably know he talks about having pigment in a finish as the best protection for UV (you mention that in your discussion of BLO).

This might send you in another direction regarding finish, but my recommendation is Sherwin-Williams WoodTech Semi-Transparent Oil Alklyd Stain. I live in northern ID at 2600 ft where the UV is intense in the summer. We also have had heat waves the last several summers-temps above 100 last week.

I've been using WoodTech since the deck was installed 7 years ago on a 1-2 year recoat cycle (no sanding, minimal scraping of flaked areas-there are very few of these). For recoats, we just use a deck wash solution, and scrub with a bristle broom for dirt. Then let the deck dry in the sun for a couple of days and recoat.

While there are some cracks in cedar boards that get runoff from the roof, all decking is structurally sound, no boards have had to be replaced.

And the Sherwin-Williams store will pigment the Woodtech to match the existing Behr stain you have on other components.

Hope this helps.
Gerry

 

Yep. High quality marine varnish. The best finish out there for boats and this type of thing. Unless you want to get into the 2k urethanes, but those aren't for hobbyist.

Why would add "stuff" to mess around with it's chemistry? Manufacturers already did all the "secret recipes" testing for you.

If it was as easy as just simply adding blo, tung oil and more solvent, then the manufacturers would put that stuff in the factory.

 

If it was as easy as just simply adding blo, tung oil and more solvent, then the manufacturers would put that stuff in the factory.

Plus, "IF" it did work, all the woodworking forums would be using it and promoting it by now.......
To the best of my knowledge, there is no "shortcut" for as-needed maintenance.
You would probably get a broader knowledge of your project by searching for:
"How to preserve & finish a redwood deck". Which, is basically what you have.

 

I have to agree with those who say use the best commercial finish you can find if you insist on having a top coat type finish. However I always caution against any type of top coat finish that is outside. All of them will eventually fail and top coat finishes are a lot harder to remove and re-finish that one of the oil or deck type finishes (I like Behr for that) that can be removed with a deck cleaner and brightener, power washer, and lightly sanded, and re-applied...... about every 3 year or so. The paint department can tint most Behr finishes to a varitey of colors for you.
As you can see con common redwood is mostly sap wood and it does not stand up to the elements like heart wood redwood does so it definitely needs some protection.

 

Ok, time to put the fly in the finish.

I totally disagree with the idea that the finish manufacturers have already figure out the best formulas and all we have to do is follow their directions and all will be well.

In the first and most obvious place, these companies are in business to make money. They do that buy selling us products. Some are good and some not so much but all are marketed to entice us to part ways with some cash. I love the "NEW AND IMPROVED" products. A product is either new or it can be an improved version. You can't "improve" something that is new. Its new. You can "improve" an existing product by making changes to it, but then it is either a new product (if the changes are significant enough) or it is an improved version of the old product. Simple logic.

In the second place, if the manufacturers truly had this sussed out, there would not be so many options on the market. We would have a discreet number of products with a clearly superior one or two for each application. This one for that scenario, that one for this. The varied opinions on this forum alone demonstrate this is not true.

In the third place, how many products from these whiz-bang companies have failed? Or do not do what they claim? If the manufacturers truly had it all under control, there would never be a failure or a product that could be "improved"

All that, of course there are great products out there and I use some of them. None of them are forever and wood in weather needs maintenance and upkeep.

My go to finish for cedar and other softwoods exposed to the elements is equal parts spar varnish and boiled linseed oil with a dash of denatured alcohol as a drying agent. A 1oz shot of denatured alcohol in a pint of mixed finish is sufficient.

I have a few pieces that are either exposed to direct sun and rain all the time or under a cover but still outside. I'm in New Jersey so heat and humidity and cold with ice and snow is all part of the package. So far so good. This fall, I need to take down and touch up my shop sign but its been up there three years and gets morning all sun and all the rain we get.

 

Thanks all for the great replies, appreciate your taking the time. Have to make this short:

1. On the McC Man a War, yes great stuff and used it full strength on an oak park bench years ago. A long story there for my next post. Diluting it now because I want to try a varnish-oil blend so I can control content, since I've tried the big box store stuff which can kinda work under perfect conditions and prep but hides the grain and looks a lot like paint. When it fails, you have to sand and start over.
2. On the finishing companies and their smart chemists, yes, correct; they are for sure smarter than me and I may yet go that way, but would likely use something like Watco/Minwax teak oil finish, though it seems they use BLO. More on that with my oak park bench restoration story later.
3. On the Sherwin-Williams WoodTech, this is the first I've heard of that and will check it out, thanks for that! I'm 10 min from a Sherwin-Williams store.

One point any of you not in California may not be aware of, we have this group in Sacramento (the capital) called CARB or the California Air Resources Board . They are obsessed with VOC (volatile organic compounds) and have instigated regs in recent years forcing reformulation of all finishes with components that want to evaporate. I'm amazed we can still get lacquer thinner, and lacquer, but it's probably next. Ethanol, methanol and MEK are gone, mineral spirits/paint thinner is badly messed up (and I'm not even talking the useless odorless stuff) so it leaves an oily film behind. I did an experiment in a tuna can in the sun 24/7 and weeks later there was still some oily stuff left behind that would not evaporate. Products like Flecto Varathane, years ago my gold standard, while still solvent based, has been reformulated such that it smells awful and I found it hard to get a nice flow by brush that leveled out well like the original. Maybe it's drying too fast, but I've switched to spray can lacquer for anything nice anyway, reserving poly for items that will get knocked around.

But for the topic at hand, all or nearly all deck/fence/outdoor surface finishes in CA, even with "oil" in the label, have been reformulated for water cleanup meaning they don't soak into the wood like oil and require only one coat only due to film buildup. Case in point Cabot Australian Timber Oil is no longer solvent based in CA, and the label stresses one coat only, not as a feature, but as a caution to avoid disaster as noted in the one-star reviews.

Is this the case with Sherwin-Williams product? Dunno yet, but will stop in when I'm over that way this coming week. Maybe they're exempt being a supplier to professional painters/finishers?

Thanks again and I'll let you know how the project evolves with photos + my oak park bench story. It turned out to be a study in comparing multiple outdoor finishes.

 

Wow, seems like you have it all figured out. Please keep us in the loop as to how it works out for you.
Plus, please post the notes and formula that you used for others here to follow.

 

I can relate to your tag line of liking to paint things. I love to restore/refinish anything wood and the worse shape it's in to start, the better. When this showed up from CraigsList my wife's only comment was "$25 for that? What a rip-off! That belongs at the dump."

Full tear-down to a pile of sticks and re-glue everything except arms. Poly wipe-on over Behlen alcohol stain. Not loving the poly patina, but it will wear well.
Milwaukee Chair Co. ca. 1930s. Was originally on the Navy base in Hawaii, thus the Navy gray paint. Likely never saw a standard finish given the circumstances. Had been sitting in someone's yard at Lake Tahoe for years (lot's of snow). The quarter-sawn oak makes it especially unique and I've found none like it on ebay (only regular oak or other hardwoods).

 

I am not sure if it is available in CA, but it is really hard to beat Sikkens Cetol or Sikkens Marine. It is the only film building finish I am aware of than breathes AND is renewable... Meaning you can apply new coats over old coats.

I have used it in outdoor furniture many times and have never been disappointed. It holds up to FL sun and rain just fine.

 

Here’s what I use for an outdoor finish mixture, using 4 parts of a durable Marine Varnish, 2 parts pure Tung Oil and 4 parts Mineral Spirits thinner. The tung oil penetrates the wood deeper than a varnish alone, gives added moisture protection and it dries fairly quick. Other than cost savings for tung oil quantity, I fail to see the beneficial need for the BLO. Unless a highlighted amber appearance is desired, its slow-drying characteristic will impede the drying time with total finishing process.

Also, depending on the final finish type/consistency, my thinner ratio may vary, so I add that last. It does help with easier application, but too much will require more finish coats.

IMO, the key protection ingredient is the final topcoat. My choice for a durable Marine Varnish has always been Total Boat. It has excellent UV protection. The “Gleam” version that I use is glossy, so a better choice may be Total Boat “Lust” for a softer, semi-gloss luster. The brand is expensive, but well worth it to me. Others brands previously suggested, I haven’t ever tried.

I’ve used my homebrew finish mixture on outdoor furniture, planters, bird houses and feeders, with great results. With much Northeastern US exposure to rain, snow, and sleet, many finishes have lasted 3+ years. However, I do cover the furniture for added weather/UV protection.

Last year, with quick 3M pad scuffs, I re-coated the uncovered bird houses, planters and feeders with 2 coats of lightly-thinned varnish only. The varnish alone, is holding up well.

 

EJP9, did any of this help you come up with a plan for your finish????

 

Yes, this was a big help and thanks all for taking the time. I painted this AM, and yes, lot's of pigment in the mix, burnt umber for a dark walnut tone; not the exact color I hoped for due to the competing red from the lumber. maybe a 2nd tint coat will darken it. There was to be another 1-2 coats of plain w/o tint to get it good and sealed. My goal is to not to have to touch if for 2 maybe 3 yrs, and then just a light rub-down with gray Scotchbrite then paint and wipe. With the film based products I've always had to do the full laborious sanding with the orbital down to bare wood.

Decided to add an extra shot of oil with BLO to change the 3 equal parts to 4 parts: varnish:tung:BLO:thinner. An experiment on scrap showed that the extra BLO flattened the slight sheen from the satin varnish. I'm looking for an egg shell or just off-flat look. It's out there curing now under a drop cloth to avoid direct sun, which seems to work to prevent bleeding. A welcomed cool-down today at only 96. We had 113 a few days ago (Sacramento) which is why I've been dragging this out. I needed a cool morning window with an non-super hot afternoon since I have to work on the hot side of the house. I have shade till only about 11am. This "cool" period is supposed to run a few more days so I can get subsequent coats on the next 2-3 days.

I'll have some photos next post.

And, BTW, the Sherwin-Williams WoodTech oil-alkyd solvent based stain suggested above is not available in CA as I expected; just stopped by the store. They had no idea what I was talking about. Their very wide product line is all emulsified oil with water cleanup. CA has declared war on most things solvent based (mineral spirits), which is why I'm going to all this trouble. But, it's odd we can still get Watco and Minwax oil/solvent based products. Maybe they're next on the hit list. The Sikkens Cetol or Sikkens Marine products are available here at marine supply stores, but sure is expensive! I priced out the DIY mix and it comes to about $20/qt at LowesDepot ingredient prices allowing for ratios/proportions. This is comparable to Watco/Minwax equivalents. I also plan to finish one bench (of 7) or railing with Watco Teak Oil to compare durability with the DIY. I've used the Minwax Teak Oil Finish a lot on fishing nets and it sets up too fast for large work. You have to move fast with it, but it is great stuff.

 

Whatever mixture you end up using, something with pigment must be used for max protection. It greatly extends refinish time. Seal the substrate with whatever mixture, then use a pigment stain on top. Pigment is the best UV protectant, far better than any of the UV stuff in clear finishes.

 

Another vote for Sikkens, the oil based stuff. You may be able to get in San Diego, because SD is not the the SCAQMD. Oil based finishes still sold there but not in the rest of So. Cal.

 

Are there still differences between the SCAQMD restrictions and the rest of California? That was true in the past, but I thought that everyone in the state has the same rules now.

Can you give an example of something that is banned in the SCAQMD but still sold in other parts of California?

 

OK, finally some results. Been hot here slowing me down a bit.

Next post, my oak/cast iron park bench saga. It's to the right in one photo below.

3 coats 24 hrs apart, 1st 2 coats with color, 3rd coat natural. Burnt umber universal tint (mixes with oil or water based).
To refresh: 4 equal parts McC Spar:BLO:tung:thinner
Adding the BLO seemed to flatten the finish some, but might skip next time.

It's final resting place. A couple more lag bolts to do when it's not 108 out there 🥵.
7 of these total, 3 down, 4 to go the rest easier at 4-6ft. This one is 8ft.

Here's why the oil-varnish blend idea. Home Depot Behr 6-8yr semi-transparent deck stain after 2 yrs.
Full sanding job do-over required.