BLO
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Tagged: patina BLO
- This topic has 25 replies, 8 voices, and was last updated 5 years, 7 months ago by Andrew Sinclair.
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I’ve not used them, but when Ed returns I bet he can give you more detail on the application of these. Shellac (usually in ethanol or other alcohol) and Danish (usually mineral spirits + oil) will both dry faster due to the solvents + drying/curing agents.
BTW, speaking of curing, if you want to finally dry out your sawhorses put them outside in the sun for a few hours. This will UV crosslink the rest of the oil.
- This reply was modified 5 years, 8 months ago by Brian A.
BLO just takes a long time to fully cure (though you could probably cut it with some mineral spirits and speed the process up a bit. It does tend to bring out the grain more immediately than say shellac but it can also give a reddish/orangish hue. The stuff is cheap but I feel like I have to be extra careful when I’m finished for the aforementioned spontaneous combustion warning (I too lie my rags out flat on a concrete surface but I still have occasional visions of flames).
I think the bottom line is that BLO has some desirable qualities but comes with some clear “shortfalls”. Depending on what you are using it on it may be a perfectly suitable finish. However, perhaps it is best used as a mixing agent with another finish to try to capitalize nuances and use them to your advantage. I know it is an ingredient in some friction polishes used in woodturning (I think just BLO and shellac mix). Since Shellac has a nice shine but dries very quickly (since it is mostly denatured alcohol solvent), I think the BLO in this mixture slows that quick-dry while allowing the shellac to still take on a brilliant shine. I also used it in a wipe-on-finish when I made my workbench (just a mix of BLO, mineral spirits and shellac). Again, allowed for an easier application process and slowed down the cure to ensure everything went on evenly and without brush strokes, etc.
- This reply was modified 5 years, 8 months ago by David B.
The BLO I have used is ok at best. It still feels ever so slightly tacky even after six weeks. I only applied the one coat too.
How do Shellac and Danish differ, I assume they are better than BLO?
Yup, that’s the joy of BLO. No thanks. Even if I had a jug, I wouldn’t use it. I don’t want it on my work. I’ve not used Danish oil, but have just a few finishes that I’ve been using (various water borne finishes, water dyes, Arm R Seal, shellac, Waterlox, and a new one that I’ve just started playing with).
27 August 2018 at 3:19 pm #550620Danish oil is whatever the manufacturer wants to call “Danish Oil” and some of it is a mixture of BLO and varnish while other brands may use Tung oil and varnish. That’s the subtle difference between pure Tung oil and “Tung oil finish”. Tung oil finish contains some varnish (polyurethane usually) and hardeners. BLO cures in about 48 hours – Danish and Tung oil will cure faster – usually less than 24 hours. Shellac is in a class of its own. It’s an alcohol soluble resin produced by the Lac bug and because it’s alcohol based, it drys very quickly. The oils are pretty durable finishes that work on about anything. Shellac will make a much shinier finish but it’s not so good for table tops and such because alcohol will dissolve it. The good part is it drys very quickly and it’s also the one thing that can be put under or over any other finish. Sanding sealer and pre-stain treatment are just a dilute cut of shellac.
When you apply BLO or any oil finish, it’s very important to let it soak in as much as it will, but then wipe as much off as you can before it starts to cure (within about 15 minutes). If you don’t, it tends to stay a bit tacky feeling as you’re describing. Take some mineral spirits and wipe your sawhorses down with it and that should help. You can put another light coat of BLO on them and rub it in with 400 grit sandpaper if you like – then wipe that off as much as possible and in a couple of days they should be good. This stuff has been the standard finish for gun stocks, axe handles, wooden hand tools, etc. for ages so it definitely works. Most people that don’t like it simply don’t know how to use it.
27 August 2018 at 4:30 pm #550624It’s really up to you of course, but I use “Tung Oil Finish” on my benches and I have always used the MinWax brand. That brand might not be available for you, but I suggest finding the stuff with a little varnish and hardeners in it just so it cures faster – not just pure Tung oil. I only use a couple of coats because I don’t want it to be too slick. Just enough so that glue doesn’t want to adhere to it and oil won’t soak into it. Over the years, my bench been planed down and/or sanded several times and each time I just toss on a couple of fresh coats of Tung oil and it’s like new again (well almost if it weren’t for a few extra holes). I don’t think shellac would be a good idea at all. You can just go with BLO but make sure to wipe it down good to remove any excess. Same thing with Tung or Danish.
27 August 2018 at 5:21 pm #550625For a sawhorse, you really don’t want anything slippery such as a varnish finish. Unfinished is fine. BLO doesn’t build, so it will work as well. A mix of BLO, polyurethane varnish and mineral spirits will work provided you keep the varnish to no more than half or so of the mixture.
Finally, as noted, the term “Tung Oil” can be one of 3 things:
a.) Pure Tung Oil, in which case it will nearly always be called Pure (or 100% pure) Tung Oil. Pure Tung Oil is not a particularly desirable finish as it takes a really long time to cure as compared to BLO.
b.) A mix of oil, varnish, and mineral spirits, in which case it will be called “Tung Oil Finish”. Which makes it really no different than “Danish Oil”, “Teak Oil”, or your own mix of oil (Tung or BLO), varnish, and mineral spirits. Everyone has their own personal favorites.
c.) A thinned varnish (with no oil mixed in), in which case it will also be called “Tung Oil Finish”. The problem is that such a finish will behave very differently from the other two, so you need to know what you’re buying. You don’t want a thinned varnish on your sawhorses, or they will end up with slippery surfaces.
Here’s something to consider as you decide what finish to use. Just about the very first thing Paul said to us was that learning woodworking is learning about risk. The further along you are on a project, especially a complicated one, the larger the risk on each step. Certainly, there is risk in applying color and finish and most of us dread it. Every time you cut a joint or flatten a surface, you gain experience that carries to future work. The same is true of finishing. Finishes are applied layer by layer and are tuned layer by layer. You learn to correct and adjust just as you learn to correct and adjust joinery. How you do this depends upon the finish and color-method you choose. So, two comments. First, finish everything you can, even “practice joints.” Finishing changes he appearance of the joint and surface and gives you a better idea of what real tolerances are. Second, look around for things built by others you aspire to build and pay attention to how they are finished. Are they done in BLO or other oil? Brushed shellac? Padded or polished shellac? Lacquer, whether solvent based or water? Figure out where you want to end up, and start using that finish. Don’t pick what is easy, quick, or “good for a beginner.” What’s more important is what can be done safely in your shop considering fumes/toxicity, flammability, and dust production, and what can be done effectively considering temperature, humidity, and limits on drying time as dictated by dust settling onto the finish, lack of access to your shop during finishing, or issues related to keeping temperature under control. Figure out where you want to end up moderated by what can be done in your shop, and start doing that.
Regarding a bench, I’m not sure I’d put finish on mine. If I did, it would probably be Waterlox or Arm-R-Seal depending upon which was sitting around and nearest the end of its shelf life. But, I don’t think I’d put finish on. Ah…shelf life. If you use Arm-R-Seal or Waterlox, get a can of Bloxygen or otherwise figure out how to eliminate oxygen in the head space of the can or you’ll throw a lot away. I buy only as much as I’ll use short term despite the higher price per volume.
The finish on your bench is whatever you prefer. My Dad’s bench, which I do not know the composition of, was turquoise paint over what was probably BLO, so it developed plenty of ‘patina’.
My current bench is still unfinished on top, as I am not done with that part, but might BLO that (I’m just a simple 6hr/wk sort with a keen desire to not breath in any more mineral spirits).
On the underlying frame I rubbed BLO and top-coated with Beeswax, mostly for expedience, and so I would not have to finish it outside due to fumes indoors, in extreme heat, and that and the ‘Association’ (aka HOA) is watching everything I do outdoors. On the legs and such there is a lot more leeway than on the top, which should not be slippery. Some leave it unfinished, but I feel that I am too messy and will drop water and other bad things on it if I do that.
7 September 2018 at 9:32 am #550980Worth remembering to go back over the linseed oil around 10 mins after applying and wipe off excess with a clean cloth – prevents stickiness.
I’m new to linseed oil but have had great results with Liberon’s “Finishing Oil” which is a chenically altered version that dries in about 5 hours. More expensive than BLO so I’m trying the latter on my bench to save money. I’d use finishing oil on projects I care about. NB I have no affiliation btw.
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