Tru Oil - How do You apply it?

[Chordophonic]

Ive just taken delivery of a Custom built Mahogany with Quilted Maple cap Thinline, hardtail Strat and a Birds Eye maple/rosewood CBS headstocked neck, I am going to use Tru Oil to finish both and would be interested to hear how You use it? Both body and neck are still in their natural state, the neck will get a light tint and the cap will be stained and sanded to pop the grain......

Id like a deep semi gloss finish and have seen all sorts of different way of using the Tru Oil, what worked for you?




Paul

 

[Skub]

A ball of cotton wool inside a scrap of old cotton T shirt. I use surgical gloves to stop me getting shiny fingers! Very light coats,a couple of hours to dry,rub with a grey scotch pad and repeat for as many times as you need. Cure for 2 weeks and micromesh the finish,then lemon oil.

 

[OpenG Capo4]

I just rub it on with my finger. I put on one drop and spread it out until it is as thin as it will go, then repeat until the whole surface is coated. You get great control that way and none of the oil is wasted. It does require scrubbing with a brush or something to get it off your hands.

After 2-3 coats to get a foundation and get everything sealed, I level it out using 0000 steel wool. Then I spray the following coats on, thinned with lacquer thinner using my Harbor Fright spray gun or a Preval sprayer. I use twice as much thinner as Tru Oil. But some have had good results using equal parts.

After spraying it on, you level and polish it as you would a lacquer finish. I sand with 600 dry to level it, then 800->1000->1500->2000->3000 wet to polish it up. Then red turtle wax rubbing compound, then turtle wax polishing compound, to buff it out. Finish it up with SC Johnson's paste wax.

(image removed)

This was done with sprayed on Tru Oil using that method.

 

[magicguitar]

+1 on finger application.

 

[Bronkowitz]

Filling the pores on figured wood, even a closed-pore wood like maple, can take a lot of coats with Tru Oil if you use the finger method.

 

[bob1234]

Save yourself a LOT of money. Seal it with shellac, THEN apply your tru oil. How you do it is irrelevant, you should be leveling it off anyway. A spray would be the easiest way, but I enjoy doing oil finishes by hand personally.

 

[tap4154]

+3 on finger application. Done several rifle stocks, and always just use my fingers to apply Tru-Oil. Stock Sheen & Conditioner for the final step.

 

[MrTwang]

I picked up a bare wood Thinline body on Ebay on an impulse (walnut top, not sure what the other wood is).

I just have it about 4 coats, applied with a cloth, no sanding in between.

It's not smooth - you can still feel the grain but I kind of like that.

It really brought out the grain pattern nicely and has hardened to a bit of a shine but not high gloss.

 

[fretman_2]

Tru Oil is pretty safe but I buy a box of nitril gloves from Harbor Freight and use the finger method (with gloves on...LOL).

This is from the master of Tru Oil Tom Pettingill (look up his laps steels here!). Follow it and you can't go wrong.

"When I'm going for a flat and shiny mirror finish I generally lightly wet sand every 3 - 4 or so coats as I'm in the building the film phase. I find that 1000 grit and a few drops of mineral spirits works well for me. Once you get within the last coat or two, you can move up to 1500 - 2000 before the last glaze coat. Being that you have basically done all the leveling as you go, if you want to polish it out you can go strait to the fine polish when cured. Sand with the grain, and let the Tru Oil cure about a week before you polish."

 

[Lostininverness]

I have a two newbie questions about how you guys do the application (hope this isn't a thread hijack?).

I've done one build with over 20 coats of tru-oil with steel wool sanding after every thrird or so coat, using the infamous finger method for application. Although its kind of gone on uniformly, I'm left with "streaks" or a kind of grooved surface because once rubbed on, I try and "smooth" the applied coat in line with the grain (like painting). Am I doing this wrong? Should I not be trying to smooth? Will this sand out once I do the wet sanding?

Also, I am doing a second build finish where I only want to apply a couple of coats for grain enhancment before coating in nitro. So the same question above, plus do I need to flat sand the coats before nitro or will the nitro make my streaky tru-oil "go away"???

Can you tell I'm not too sure what I'm doing?

 

[loversmoon69]

I have done both the finger method and taking a small piece of cotton or folded piece of torn shirt and then wrap it up in a small square piece of t shirt.

 

[Bronkowitz]

You shouldn't have to smooth it in line with the grain. The coats are so thin that the grain direction is irrelevant. If, once rubbed in, you can still move it around to form streaks, it sounds like you're putting it on too thick.

I cut a small half-moon shape in the foil, cover it with my finger, and tip the bottle. It's maybe a drop of oil on my fingertip. Then I just rub it on. I get maybe 20 square inches of coverage with that amount. I stop rubbing when my finger stops moving smoothly and starts to skip over the surface. Then I put more on my finger and repeat on an unoiled part.

 

[old_picker]

Also, I am doing a second build finish where I only want to apply a couple of coats for grain enhancment before coating in nitro. So the same question above, plus do I need to flat sand the coats before nitro or will the nitro make my streaky tru-oil "go away"???

Can you tell I'm not too sure what I'm doing?

ditch either the tru-oil or the nitro - either will make a decent finish
trick is to use in both scenarios many light coats - with truoil, all you need to do is get enough on there to colour the surface - a lot less is a lot more

with any oil finish you want it as thin as you can possibly make it
a rag dampened with the oil and wiped over the surface is plenty
if you get it on very thin you can't get streaks -

tru-oil is not rubbed into the surface it actually builds a skin on it - unlike tung, boiled linseed and to a lesser extent danish

if you want to make it a no brainer on the second build with ultimate "grain enhancement" try a good brand of danish oil

to prep the job sand the surface to 2500 grit or until the wood surface is reflecting light
now you are ready to apply finish:
flood the surface with danish and leave 5-10 minutes
wipe it all off and leave 24 hours
repeat steps one and two, twice more
you are done

the finish will have a satiny, glowing feel that you will not want to stop touching, the grain will be evident if it is a coarse grain timber - to me that is better than a shiny coating of chemicals that does not allow the tactile feel of the polished wood

now we have well and truly hijacked this thread

 

[Tom Pettingill]

Tru Oil is a very forgiving finish and everyone will find a way that works best for them. I wipe it on with a piece of old cotton t-shirt and spray the last coat or two. For spraying, you can thin Tru Oil up to 2 parts Tru Oil to 1 part mineral spirits. Less is better and definitely test first. You can also buy Tru Oil in a spray can. It works great and is handy to have around even if you mix your own for spraying.

A couple things to remember / consider. Tru Oil would better be described as an old school oil varnish and will build a film. Being in the varnish family, it does not burn into the previous coats as a solvent finish like nitro will. Because of this, I basically level as I go to avoid witness lines at the end. Being that Tru Oil is not a solvent finish, it relies on a chemical reaction to cure / harden. In this case it is absorbed oxygen from the air that kicks it off. This is the primary reason you want to keep your coats thin. Too thick and the O2 can't get in.

If your a glutton for punishment, you can do a flat mirror gloss finish with Tru Oil. No big secret to it, just lots of time and sanding between coats. Keep at it till its all flat and level, then spray the last coat or two.

.

 

[Bronkowitz]

Is it really cost effective to cut it with thinner and just spray a couple coats? I get it in a 3 oz bottle for $10-$15.

 

[Lostininverness]

I stop rubbing when my finger stops moving smoothly and starts to skip over the surface. Then I put more on my finger and repeat on an unoiled part.

That makes sense, I've had that where it the tru-oil feels kind of tacky, but I often didn't take it that far - too thick then! So I should be taking it to that point of tacky?

Old Picker - I've already made the call on the finish I'm doing - its a nitro colour coat on back and sides, with the tru oil front for grain, and then nitro over top for getting flat. So will I be able to flat sand after 5 coats, and then spray with nitro? I am concerned about getting witness lines. If so, any advice on grits of paper (wet....dry...) to use? thanks for the idea of Danish, I'm keen to try different finishes to see whats what.

Tom - your work is just incredible! The body that I have tru-oiled (pics below) all over has some stickies stuck on the surface and dimples - is this going to flat sand out?

All advice welcome!

 

[jimibob68]

how much different than tung oil

 

[old_picker]

So will I be able to flat sand after 5 coats, and then spray with nitro? I am concerned about getting witness lines. If so, any advice on grits of paper (wet....dry...) to use? thanks for the idea of Danish, I'm keen to try different finishes to see whats what.
All advice welcome!

the danish idea was for the 2nd body
will you be able to flat sand after 5 coats? dunno man how thick or thin are your coats

for danish oil - grits of paper ? go from raw machined timber 180, 240, 320, 400, 600, 800, 1000, 1200. 1500, 2000, 2500 , further if you want

 

[Vizcaster]

how much different than tung oil

"Tung oil" is often a misleading label. It's possible to buy pure tung oil, but rare indeed. Rather the can probably says "Tung oil…finish" and is likely trying to describe how it is a varnish (maybe a thinned down wiping varnish like Watco used to be) and the most expensive component is the oil - so they make a big deal of saying it's "tung" oil as opposed to linseed oil. Still not telling you that the primary ingredient is a solvent (probably a mix of them, basically paint thinner or mineral spirits or naphtha), and a very important ingredient is the resin (alkyd, phenolic, polyurethane). So be careful buying an "oil finish" unless you know if you're really getting an oil with dryers (catalyst) or a wiping varnish with a resin component.

So, really, it's hard to say if Tru Oil will perform better than the "tung oil" you had in mind, but I can say this - you know what you're getting with Tru Oil and if you have the patience (I don't) you can get a guitar shiny with it.

 

[Bronkowitz]

FYI, this is from page 77 of Understanding Wood Finishes by Bob Flexner, 2005.


"As previously explained, linseed oil and tung oil cure slowly by absorbing oxygen. The curing can be speeded up significantly by cooking the oils first in an oxygen-free (inert-gas) environment at about 500 degrees Fahrenheit until they thicken. This, or an equivalent process, is what is done with at least two products that you may be familiar with: Southerland and Wells Polymerized Tung Oil and Tru Oil. Tru Oil is widely available as a gunstock finish. These products act more like varnish than linseed oil or tung oil.

"Cooking linseed oil and tung oil in an inert gas causes them to crosslink without going through the oxidation process. This changes the oils so that they complete their curing rapidly (faster than varnish) when exposed to oxygen, and it makes the oils cure hard and glossy. In contrast to normal linseed oil and tung oil, therefore, it's possible to build the oils to a thickness on the surface of the wood.

"These oils need a name. They are sometimes referred to as "heat-bodied," a vague term that simply means cooked and made thicker, usually in the presence of oxygen. Because the product that is sold to woodworkers is labeled "polymerized" oil, it makes more sense to call them polymerized oils. In this context, polymerize simply means crosslinking, and these oils have been partially crosslinked before you buy them, so the name makes sense. You have to be careful with the word "polymerize," however, It is often used by manufacturers as a marketing term to make you think you are buying something special when you aren't.

"There are two problems with using polymerized oil as a finish on large surfaces such as furniture. The oil cures fast, so getting it applied and the excess wiped off before it begins tacking up can be difficult; and you shouldn't apply the oil in thick layers like you do varnish, or tiny cracks may develop in the film. For small objects such as gunstocks, hoever, polymerized oil works superbly."