Linseed Oil

[neilm]

I've read a few boat building books and linseed oil keeps coming up especially by John Gardner. What is so magical about Linseed Oil and what does it do for the wood? If I'm air drying green wood at what moisture content should I apply it? Why is Linseed oil used instead of Tung, Danish, Teak oil etc. Thanks.

Neil

[sdowney717]

I think it grows mold and turns black after a while. At least it did on the inside of the sliding doors after 2 or 3 years.
How do you clean it off, do you have to use a 2 part bleach or will regular chlorine bleach or oxalic acid work?

[TMny]

>Why is Linseed oil used instead of Tung, Danish, Teak oil etc.

I think mostly because it was the most proven resin/vehicle for coatings before WWII. Also , cheaper than the others mentioned , i think.

Linseed is a DRYING oil , hence a natural varnish. Because it's natural , it seems healthy for the wood , but may promote rot insofar as it is food for many critters. It'll attract dust and bugs and fungi if not in bright sun ... a modern varnish , thinned , might do a better job in those respects.

[Steveh]

It’s a good all round natural product. Used in all sorts of applications. It does tend to promote growth of mold if left outside or in damp/humid conditions. Am presently restoring a 100 yr old boat and have been feeding the timber with linseed. I am following with red lead paint as a primer which is also reduced with linseed oil. A lot of older paints were linseed oil based but not many paint manufacturers today will guarantee their products if used in conjunction with linseed.

Is a good additive in a slush mix of stockholm tar, varnish, and dryer for galvanised rigging. There are several recipes for complete drying or tacky finishes. Impregnate wooden blocks by heating slowly over several hours emersed in linseed then wax or leave oiled. See thread on roped stropped blocks.

I have come to find that it is used more in traditional finishes and uses rather than modern applications of hi gloss varnishes etc.

Have read with surprise that soaked rags can spontaneously combust. Pay attention if leaving stuff lying around.

Check this link for more http://en.wikipedia.org/wiki/Linseed_oil

[NealmCarter]

Exothermic Spontaneous Combustion....now that makes me shudder!

[Jim Ledger]

It's good to remember that spontaneous combustion can occur with ANY oil based product, including paint, tung oil, teak oil, danish oil, oil varnish. It's not just linseed oil.

I've seen factory situations where rags were immediatly placed in special metal containers with self closing lids, filled with water. Possibly an OSHA requirement but why take a chance.

[tomdownard]

I find that most marine products are just inexpensive products that the seller bought in 55 gal drums, added a few things, and repackaged and sold for 5 x the original cost. I was an ink maker for 5 years and the expensive inks for lumber are very cheap to make. Can anyone give up some formulation info on making inexpensive varnishes, paints, glues etc. into quality marine applications? I am restoring two classic Express Cruisers and West Marine products are retail plus 10%!:mad:

[pcford]

I find that most marine products are just inexpensive products that the seller bought in 55 gal drums, added a few things, and repackaged and sold for 5 x the original cost. I was an ink maker for 5 years and the expensive inks for lumber are very cheap to make. Can anyone give up some formulation info on making inexpensive varnishes, paints, glues etc. into quality marine applications? I am restoring two classic Express Cruisers and West Marine products are retail plus 10%!:mad:

Oh, you say marine products are ordinary products with marine stamped on the can and a huge mark-up.

Never heard that before. At least not this morning.

[Dave Gray]

Many moons ago when the world was young (or I was anyway) I worked in a hardware store. Some folks had been using linseed oil in remodeling a house and had stuck rags in a bucket. They combusted and the remodel went up in flames. One of the project people was considering suing said hardware store and the oil manufacturer - he was convinced the fire was due to mixing linseed oil from one gallon into another gallon - but fortunately it didn't go anywhere.

[Bob Cleek]

No, "marine" coatings are NOT (generally) non-marine products with a boat on the can. There are a few exceptions, but not many. For instance, I've never detected any difference between "Penetrol" and "Marine Penetrol." There is, however, often little difference between "generic" materials and "labeled" ones. Oxalic acid or "wood bleach" in the paint store is the primary active ingredient in most all "marine teak bleaches." No need to pay for "teak bleach" that is just oxalic acid dissolved in water.

There are also ordinary coatings that are "close enough" to "marine" coatings that you might consider using them. For instance, Rustoleum's oil based gloss paints have a good solids content and fine abrasion resistance. They will work as well as, and cost a quarter of the price of, "marine bilge paint." Latex house paint, on the other hand, is not really properly suitable for marine applications. It takes experience and experimentation to know the difference. (Maybe that would be a good thread topic sometime...)

Beyond such exceptions, unless you are sure, you are better off going with a product offered by one of the main marine coatings manufacturers. You may indeed be paying more "just for the boat on the can," but you aren't likely to find the same formulation intended for the application without that "boat on the can."

As for "exothermic reactions," I find it rather amazing that the several posts above imply that the fact that oily rags and other combustible materials, and particularly rags soaked in linseed oil, might spontaneously burst into flames is some sort of "discovery." Time was, when oil based paints were commonly used, this simple fact was common knowledge. Maybe it is time to rethink the "safety" issues here. Apparently, what used to be "common sense" and "common knowledge" is no longer!

[pcford]

Many moons ago when the world was young (or I was anyway) I worked in a hardware store. Some folks had been using linseed oil in remodeling a house and had stuck rags in a bucket. They combusted and the remodel went up in flames. One of the project people was considering suing said hardware store and the oil manufacturer - he was convinced the fire was due to mixing linseed oil from one gallon into another gallon - but fortunately it didn't go anywhere.

Many moons ago, I worked in an antique store. Several years after I left, the place burned because of Watco soaked rags. I have heard that Watco/Danish oil is the worst for fires.

[Dave Gray]

Yes, I think that is why Watco wasn't produced for a few years due to liablility lawsuits.

[dmede]

I've read a few boat building books and linseed oil keeps coming up especially by John Gardner. What is so magical about Linseed Oil and what does it do for the wood? If I'm air drying green wood at what moisture content should I apply it? Why is Linseed oil used instead of Tung, Danish, Teak oil etc. Thanks.

Neil

If you want it to penetrate I would apply with turps to dry, warm wood. Keep it wet until the wood won't absorb anymore, then wipe down and let dry. Gardner and others advocated sloshing LO around the inside of a hull to let it soak it up and help prevent unwanted wood movment when the boat dries out. Old versions of boiled linseed oil were in fact boiled after being cleaned. Modern BLO is just raw LO with driers added, this means it has extra protein in the oil which may be responsible for the black mold most people associate with the use of LO.

Check these guys for true cleaned and boiled LO: http://www.solventfreepaint.com/

From my understanding oil finishes like Danish & Teak are usually mixes of LO and Tung oil with thinners and driers added plus some varnish. You can make the same mixes at home for less (I do). A lot of furniture guys use LO undercoats to make the grain of the wood pop. Wetsanding with LO is a great way to get a nice finish that you can then cover with varnish.

[Dave Fleming]

http://www.solventfreepaint.com/index.htm

David, is right on with this site. I suggest anybody contemplating using Linseed Oil read the 3 page PDF on their Linseed Oil, it's blending with other ingredients and, how to use.

I have precious little painting experience and, what I do or did have was before one had to be a junior chemist just to read the info on the can.

It was all oil based paint or varnish.

For furniture or interior joinerwork finish Dalys Sea Fin Teak Oil was used.
First coat or two thinned down with the appropriate vehicle and each coat wet sanded to create a paste that filled the wood pores creating a very smooth, sturdy finish.

SWIMPAL did the Black Cherry sign we had hanging outside our shop in Anacortes, WA., with 7 coats of Dalys applied as above. Once a year it was taken down and given a refresh coat, period.
No problems from hanging out there in the rain, snow, wind, sun and cold for the 3 years we had the shop.

[Bruce Hooke]

I find that most marine products are just inexpensive products that the seller bought in 55 gal drums, added a few things, and repackaged and sold for 5 x the original cost. I was an ink maker for 5 years and the expensive inks for lumber are very cheap to make. Can anyone give up some formulation info on making inexpensive varnishes, paints, glues etc. into quality marine applications? I am restoring two classic Express Cruisers and West Marine products are retail plus 10%!:mad:

You might also want to try shopping around a bit on paint & varnish. West Marine is not necessarily the cheapest place. Check the prices from places like Jamestown and Hamilton.

Keep in mind as well that the added cost of getting less than barrel quantities is not specific to the marine industry. It is simply a lot more efficient for a manufacturer to sell something in 55 gallon drums than in quart containers, so you pay a large markup for the convenience of getting something in quart containers.

[Alixander Beck]

What's nice about Linseed oil is that after time it kind of congeals. It becomes a little waxy.

The advantage of this and why I use it is that not only does it fill the wood fibres like all oils but that when it congeals it remains in the fibres much longer than "regular" oils. That being said, I am not 100% certain there are other oils that do this.

What I have learned from my father is to cut the Linseed with a high grade Turpentine to deepen the penetration of Linseed into the wood. The turpentine evaporates and the Linseed is left.

Another additive used is Lavander oil into the mix. This probably doesn't apply too much to boat building where wood is usually coated with epoxies or urethanes but it adds a wonderful level of 3rd sense to furniture pieces or anything left un-varnished.

I finish my pommels this way on paddles followed by some wax.

[dmg]

Neil

Checking past threads on this topic will probably tell you everything you want to know.

35-40 years ago, we used boiled linseed oil/turpentine mix to seal wood that was either very dry or worse case, slightly weathered from failed paint/ coatings. It worked very well. Our thinking/experience showed us that NOT using it allowed the dry/weathered wood to soak up all the oils in the paints/varnishes thereby shortening their useful life.

We never intended it to be a finish coat in any sense of the word, simply a sacrificial coating.

This also was practically the only way to re-do the putty glazing on windows and doors that had some age/history. With out the BLO coating the glazing would fail in a couple of years.


Back then, practically everything was still more or less oil based products, so the oil based sealer coating worked very well.

About all I use the mix for now is once in a while, coating/sealing some woods that take a stain unevenly, or projects like raised panel doors with a lot of both face and end grain to stain. It tends to allow a more even stain coating.

Dave

[ken dibnah]

Has anybody tried to use linseed oil paint? I have bought a quart as my window frames are apart for rebedding and the claims of long life and no solvents is attractive. I already use Le Tonk for the brightwork and plan to add some to the paint for the added gloss. I also wish to repaint the door. Brightsides and that ilk look good but I don't like the danger warnings on the label...

[Cuyahoga Chuck]

Linseed oil, in the "boiled" form, has been an ingredient in common house paint for over one hundred years. It may have it's benefits but, there are other drying oils, some of them the products of modern chemistry that are as good or better.
Whether modern paints can benefit from a dash of linseed is just a guess.

[dmede]

Linseed oil, in the "boiled" form, has been an ingredient in common house paint for over one hundred years. It may have it's benefits but, there are other drying oils, some of them the products of modern chemistry that are as good or better.
Whether modern paints can benefit from a dash of linseed is just a guess.

If you read the www.solventfreepaint.com site it sounds like using LO paint allows you to rejuvinate the paint down the road by simply applying straight or thinned LO to the painted surface, as opposed to sanding and reapplying a top coat of modern paint. Sounds nice. I was contemplating using this paint on my skiff but they don't have free paint samples or chips and I'm not forking out $30 - $50 to pick a color.

[ken dibnah]

I'm going to use some on my first window this weekend so I'll let you know how it works.

[dmg]

Ken

Not sure what you mean by doing the first window. Repaint or reglaze, or both ?

If you are reglazing or redoing the putty only, check around at some glass shops or wood shops that reproduce check rail windows. You really need an oil base putty ( boiled linseed oil ) if you can p/u a few handfulls somewhere. As far as I know, Leekproof products in ( Chicago ? ) was one of the few makers of it.

It used come in 5 gal. steel pails, thats why I said handfuls ! Primarily was used by volume glazers. I used one pail in about 4 days,( usually one day a week for 4 weeks) of course it took 3-4 days to make all the sash first.

Dap has a glazing compound that works OK, if that's all you can find.

Dave

[ken dibnah]

Well, its raining, so no painting. The frames are attached to the side of the house and are still bedded very nicely. The inner frames are held in by dolfinite bedding and a screw or two (really glad I'm getting a chance to fix all the P.O.'s work) and all I have to do is pull the screws and the frames that hold the glass in, pop out. The track is on the boat, waiting for me to Dremel a copy, and I will bed it all again and reassemble. That was supposed to happen yesterday but it rained so hard, the locals are building an ark!

I am going to use linseed paint (white white) with an ounce or so of Le Tonk for added gloss. I was hoping somebody else had tried this method...I will let you know how it all works, how it dries, how shiny etc. I also want to use it on my back door.