How do you apply Tru-Oil?

[RestlichGeist]

I've been using Tru-Oil for quite some time now, and I've been getting excellent results on wooden plectrums, trussrod covers and other items that only have small, flat areas that need to be finished. However, with necks and especially bodies, I just can't apply the stuff evenly, no matter how I try to do it.

I've tried applying Tru-Oil with old t-shirts and other kinds of cotton rags, a French polish pad, toilet paper, coffee filters, bare fingers... and always end up with an uneven, ugly top coat. The first couple of coats sometimes work out fine, but after about five or so, the Tru-Oil seems to dry almost instantly. There's simply no time to touch it up or even out the coat at all after it's applied, and most of the time I don't even have time to do a full coat before it's already sticky, even on a neck.

What am I doing wrong?

[maull]

I have not tried it yet but I have heard that you can wet sand it using linseed oil to create a slurry that will fill in voids, level your finish, and eventually solidify again.

[ScottR]

I am curious about the reponses to this myself. I haven't heard of the linseed oil slurry. I have used this stuff once and wet sanded with tru oil to get the grain filling slurry....but it doesn't come out completely level. I always assumed I was going to have to level sand and buff it after curing like any other film finish.

I do know it can be sprayed, which may be the best bet for the final coats.

SR

[SwedishLuthier]

You are not telling us if the wood you are trying to finish is porous like mahogany or if it is non-porous like maple. If you need to fill the pores Birchwood Casey makes a filler/sealer that is made for Tru-oil. If it is the final touch we are talking about, this is my order of work. First couple of layers, go thin. wipe off all excess. Use a lint free rag or more or less anything to apply the oil. Do not let the oil get too deep into the wood, especially on acoustics. Then, when the surface has begun to look wet, just add layers until you have a build up of finish. At this stage you can go a tad heavier on every layer. Next is to level the surface, using 1200 grit paper of similar, making sure to not sand through to bare wood. After that you put on as thin layers as possible, using a quite dry rag of a coffee filter, the last is my preferred applicator for this stage. And yes, the layers will dry almost instantly. And you will still see the scratches from the sanding after one, two or even three layers. Byt add new layers, avoid spilling or dripping or drag marks and with time you will get there, creating a smooth and semi-glossy surface. If you want to get it up to full gloss, you need to cut and polish the film created by the oil just like you would with a lacquer (describes in depth all over this place).

Birchwood Casey does make an aerosol version of their Tru-Oil but I have yet to test it.

[Prostheta]

I would add that using recycled paper coffee filters is a bad idea. They can shed fibres. Virgin paper filters are better. Adding thin coats is not too dissimilar to how you apply French polish. The thin film should leave a "comet trail" which flashes off behind the strokes. The applicator should be moving as it hits and leaves the surface. Imagine a plane coming in to land, running along the runway a bit before taking off before the end. That helps prevent smudging.

[verhoevenc]

Gimmie a couple and I'll export that section of my video and upload it.

Chris

[verhoevenc]

I'm always baffled by how long export/upload takes sometimes?!

Chris

[SwedishLuthier]

Great stuff as usual Chris

I don't use the circular motion but rather along the grain and I don't get the swirly pattern Chris mentions. I think I might get the same type of "drag marks" but as they are in line with the grain they don't show up in the same way. Some things that Chris and Carl stresses better than I did:

-Get it on super thin, think "polish" rather than "apply"

-Look for the "comet trail" of drying oil. Then you know it is thin enough

Also good to remind us of the self combustion risk Chris, can't stress that enough. I usually use a thin disposable vinyl glove when applying Tru Oil and just wrap the cloth in the glove to make sure no air gets to the rag, thus stopping the violent curing (oxidation) process.

[Prostheta]

I'm with Chris on this one. Very well-explained! The last instrument I used Tru-Oil on was my 5-string Carl Thompson tribute bass. The entire instrument is Sapele aside from a little Ebony and Wengé.

I started with a "flood coat" which as mentioned isn't ideal for an acoustic. I find that this "wets" the wood and helps the slurry bind up in the pores. This is all wiped off well before it starts to set up. It just helps with adhesion, or at least it feels like that in my head. I then did the same slurry fill by wet sanding the surface with oil; not so much oil that the paper felt that it was gliding on a layer and not touching the body but enough that it doesn't dry up into bits of debris. I bet the aerosol version would be excellent for continual wetting. The oil sanding doesn't need to apply oil to the surface as such, just to flatten it and close it up. After that it is the light wiping.

Tru-Oil seems quite forgiving for a drying oil as long as it is not laid on heavily and left to its own devices. The only time a large amount of oil ever seems useful is that initial flood coat, which is not always and is perhaps never actually necessary.

[SwedishLuthier]

More Tru oil tips: if you use Birchwood Casey they have a thin foil cover on the bottle neck. I poke a small hole in the foil rather than just ripping it off. This slows down the drying process in the bottle and increases shelf life.

[Prostheta]

Additional tip: If you have an open bottle, store it upside down (put the cap on first) so that air in the bottle does not causes a film to form over the top surface of the oil. For the larger bottle, squeeze it until the level of the oil raises towards the cap before closing it off to reduce the volume of air inside the bottle.

[pan_kara]

Hah, perfect timing, I'm just doing attempting a tru-oil finish on my V build at the moment. Thanks for the video too!

What is exactly the purpose of wiping the finish off at the beginning? On the neck I've put on two pore-fill coats (gotta get the filler next time I'm buying truoil) done by applying the oil _with_ P320, rubbing it on until it gets sticky and then leaving it all for 48h to harden well. At this point the guitar is really looking dull and dirty. Around the third coat I do try to polish the sticky mess off with a rag, uncovering a more or less flat surface with a satin shine.

Then I try to put on thin layers similar to what Chris is showing, though looks like the pad is a much better idea than the coffee filters I'm using. Gotta try that.

Also, putting on a bunch of heavier coats at this stage, then levelling and then going to the light coats - like SwedishLuthier says - will probably make more sense for me and build a thicker film.. I'm going for the high gloss finish.

[Prostheta]

I'd say go with what works for you. I've read all manner of methods online over the years, some advocating themselves as "the" method and bashing others unfairly. What works for me is based on what I need. A basic grain fill and level satin finish which ends up being waxed and buffed. The only reason I use a thick initial flood coat is to promote soaking and subsequent surface adhesion/cohesion. My target is a reasonably thin and maintainable film finish as opposed to anything thicker.

The flood is never allowed to set up (except for perhaps a little surface skinning which is wiped off anyway) in the wood before it is wiped off. I feed the wood until it stops wanting to drink the oil (watch for pores breaking the surface of the oil as they suck up oil) and then leave it to stand. Wiping clean allows air to reach the wood surface so the oil that has penetrated the wood can start linking up. After that, the slurry filling stage appears to become more successful in producing a tightly packed and solid surface. Without it the oil in the slurry wicks away into the wood making the slurry dry and difficult to work in. Whilst it wastes a lot of oil initially, it makes subsequent stages more effective and economical.

At least, that is my experience. I read so many different accounts that I ended up just hybridising them and figuring out what worked for me. Testing on scrap is tedious but helps.

[pan_kara]

Interesting concept with the flood coat. I gotta try this. Meanwhile I'm beginning to understand the need for wiping off, at least the slurry coats - I did wipe off the second one, had to use mineral spirits since by the time I finished the body the parts where I started were too dry to come off easily.

Anyway looks like I didn't manage to get it fully off in places, and now after two more light "finish" coats its starting to show. Looks like the upcoming coat will involve sandpaper again...

[Prostheta]

I have to be honest with you though, I have no idea whether the flood makes any solid difference. Same as I can't tell whether the general purpose glue we have at the school is any better or worse than Titebond-I for instruments, I still use the Titebond out of knowing it works. Tru-Oil is more testable but I guess that since I have my method that bears me good results and is repeatable, I don't need to alter the method. Unless specific advantages are available - less waste and cleanup, quicker finish time or whatever - I think that I am right in sticking with what works for me.

This does make it difficult to recommend a course of action for other people though. So many other Tru-Oil enthusiasts vaunt their methods as being the-one, so I'll try not to fall into that thought trap. Try all of the ideas presented and see what you prefer. Tru-Oil is a product that teaches you a lot through use. It can be screwed up, but more often than not it can be recovered and repaired. I decided to finesse the headstock on my CT tribute bass yesterday and all the oil took to repair it was a wet finger rubbing in oil to the exposed area, then rubbing it off.

[RestorationAD]

The flood coat idea is a hold over from other oil applying techniques.

When using Teak Oil, China Oil, BLO recipes the usual procedure for the first coat is to flood the wood with oil and keep a coat of oil on it until it stops sinking in. Then after the wood will not take any more oil wipe excess from the surface. Of course depending on the type of oil you may need to "chase" the oil that weeps from the pores several times after.

I usually let this sit overnight and then sand the instrument with 400 grit to 600 grit wet/dry paper using the oil as a lubricant. The slurry that builds can be forced into the pores with a rag after sanding. Wipe excess let sit.

After about 3 days you apply another thinner coat. This coat can be applied with a rag and the excess wiped away after. Rinse repeat a few more times and leave to cure until the wood stops smelling of oil.

In general I would say Tru-Oil is not a desirable finish for an Acoustic guitar. A wipe on poly is a better idea for an Acoustic.

For Tru-Oil the techniques are varied.

Here is a repost from my Blog.

I guess if you still wanted to use Tru-Oil here is what I did. I put three coats on with nitrite gloves. No rag. You have to be very careful to not have any runs or drips.

Varnish drips and runs are hard to sand out as the middle of the drip stays wet. The resulting soft centered fisheye is hard to sand out.

I work in this order. Headstock face, headstock back, hang the guitar on the hanger, do the neck, sides, then the back, then the front.

Use the gloves to squeegee the surface of the body of excess oil. Once you have it smooth don't touch it again as you will leave marks. Tru-Oil doesn't flow out really well.

3 coats a day. At least an hour between depending on the weather.
After 3 coats I was using 0000 steel wool. But steel wool leaves a mess and has to be blown out and wiped down carefully.
I decided to use 600 grit wet or 2400 MicroMesh wet. It was easier to clean up.

You can fill pores in Tru-Oil by sanding with 400 grit using Tru-Oil as the agent instead of water. Let it dry a little then wipe it off cross grain.

[Prostheta]

Excellent. Good call on the source of the flooding technique. I'll try not doing it on some scrap (that sounds counterproductive...not doing it) next time to exorcise myself of this habit. ;-)

[wellie]

Hi There take look at this website,tried it myself with great results on solid bodies.Web site is " well oiled with adamson" All the best

[SwedishLuthier]

Hi There take look at this website,tried it myself with great results on solid bodies.Web site is " well oiled with adamson" All the best

Thanks for posting. Here is a direct link

EDIT: Had a quick look at this (still not finished the complete essay). It looks really good. If you did the writing (= no copyright infringements) this would make an excellent tutorial to re-post here on the forum. If you have some photos it would be even better...

EDIT2: After reading through it all I guess that you are not "Adamson" and we will have to do with a link. Maybe I'll try this exact working scheme on a Alto Acoustic being completed any time now and snap a few pics to show this method a bit more graphical...