Spraying Tru-Oil

[Old-Duckman]

I am new to muzzle loaders but not new to firearms. I have finished and refinished gun stocks, grips etc for decades. Some things I have learned about spraying Tru-Oil might help others. This is going to be a long post.

I use a Paasche SI airbrush.
#3 Needle
The end of the needle protrudes from the back of the brush 1/4"
If you buy this brush also order 1 Oz. glass bottles (VL-1-OZ). The plastic bottles that come with a kit are junk, I use them only for holding naphtha for cleaning purposes.
Order a reamer (VL-54). Trust me you will end up needing it sooner or later.
I have 2 extra triggers on hand (SI-10), I will explain this later.

Years ago I used lacquer thinner to thin the Tru-Oil for spraying. I don't know when the formula changed but lacquer thinner no longer works, use Naphtha as thinner.

Process for preparing and spraying:

I put one to two coats of Tru-Oil on by hand scuffing down between coats.

I use 3M scuff pads not steel wool. I use the grey ones for most of the process but knock down in coarseness to the tan pads as the finish nears completion. [These pads are numbered for body work as 1 (maroon), 2 (gray) & 3 (tan), I get them from Amazon in a roll].

Scuff down the cured finish leaving no shiny areas.

I then dust off the stock with a good quality paint brush. Then hang the stock and use the airbrush (without a bottle attached) as an air gun to blow off the entire stock concentrating on "nook and crannies" you will see the dust being blown away from these areas. After this. lightly rub a tack cloth over the stock.

I use about a 3:1 (Tru-Oil to Naphtha) mixture. Strain the mixture through cheesecloth. This is important as thick Tru-oil will clog the airbrush and you will get a very limited amount of finish coming through the brush.

I use this compressor, purchased from Amazon, it is an excellent little compressor Amazon.com Set your regulator to 40 PSI with the trigger pressed.

I always trigger the brush off of the stock and then move to the stock to begin spraying. I stay approximately 8 to 10" from the stock.

Spray on a rather light coat as it is easy to get runs. Let the finish set (flash off the thinner) for 1/2 a minute or so and look over the stock. If your coat is too heavy it helps to hold the stock horizontal so that runs do not form. If runs have formed you can gently touch them with your finger tip and that will usually take care of them if they are not too large. At this point if you see any areas that need a bit more finish you can spay on more being careful to not over do it.

I then move the stock to my drying box, that is simply a wooden box with a 100W light bulb in it. Let cure overnight and repeat the process.

After 6 coats or so you will want to wet sand with 400 grit wet or dry paper. You will sand through the finish in places, don't worry as you will be finishing over those areas with plenty more coats of finish. Scuff down after sanding and apply another coat.

I like to have all the pores of my stocks filled and depending on the wood in question depends on how many coats you will need and if you will need to wet sand more than once.

Cleaning the airbrush: This may sound crazy and you wonder why I add it but a clean brush is critical to good results.

Once done applying finish trigger the brush to get any remaining finish out of the brush. Attach a bottle with straight naphtha and spray into a paper towel for several seconds. Unscrew the handle assembly from the body of the brush. Be careful as the trigger will no longer be attached to the brush and it is easy to lose (that is why I suggest that you have at least one extra trigger on hand).

Wipe the body of the brush with clean naphtha. Wipe the needle as well, this must be done after each use. Feel the needle and if it is not smooth for its entire exposed length, lightly clean it with 4-0 steel wool then re-wipe with clean naphtha. You can trigger the brush without the handle/needle assembly attached but you have to insert the trigger to do so.

Carefully reinstall the handle/needle assembly, the trigger must be placed in the brush prior. I make sure that I have a good view/light as I look into the back end of the brush to insert the needle. The tip of the needle is very fine and a heavy hand here can damage the needle. I keep extra needles, tips, O-rings and triggers on hand.

I wear a respirator during the whole spraying and cleaning process!

I hope this lengthy post might help those who might want to spray Tru-Oil.

 

[FishDFly]

Should be saved as a sticky.

 

[Tyler L]

Thanks for the write up. I had always wondered if Tru Oil was sprayable.

Do you find spraying it takes fewer coats? I remember when I did a walnut guitar body, I wiped on around 28 coats and wet sanded periodically before I was satisfied.

 

[Old-Duckman]

Thanks for the write up. I had always wondered if Tru Oil was sprayable.

Do you find spraying it takes fewer coats? I remember when I did a walnut guitar body, I wiped on around 28 coats and wet sanded periodically before I was satisfied.

Tyler, it has been so long since I used Tru-oil by hand rubbing only that I really can’t scientifically compare. But I can tell you this, far more material is applied when spraying then when applying by hand. So it stands to reason that fewer coats would be needed to reach your desired finish.

 

[Eric Krewson]

If you have the proper equipment, I am sure your method is superior and quicker than hand rubbing. As a selfbow maker I hand rub my finishes on, all custom laminated bowmakers spray their finish on because they use very durable epoxy finishes that don't lend themselves to hand application.

I apply Tru-oil scrubbed in with a soaked scotch bright pad and quickly wipe off the excess, I get a very nice satin finish this way. When I finish a gun, it is a one off and I am not in a hurry, several days and 5 or 6 coats later I get a finish I really like.

 

[Old-Duckman]

Eric,

I wouldn't say that my method is superior at all, its just the way I prefer to apply a finish. I figured that many on this forum would eschew airbrushes, compressors etc.

I am finishing 3 pieces of wood at the present time. A stock for a Pedersoli kit Scout Carbine (I will post pix when finished), a butt stock and forend for an unmentionable...think 37, a nice example with a 1948 date of manufacture that a PO had tried to fit a pad to and jacked it up. Thanks to that person I got a good deal on the piece.

Anyway all that really matters is that anyone who does anything should be pleased with their results, as we both apparently are.

One nice thing about spraying is that you can add oil based stains to the finish and play with the stock color that way. I only do this on rare occasion and only once all pores are filled and there will be no more wet sanding, just light scuffing. I'm thinking about doing it to this Scout stock but still undecided.

The finish on the stock in your photo is very nice BTW !

 

[ZUG]

I sprayed Tru-Oil that was thinned using a Binks # 24 touch-up gun in the late 60's and early 70's on modern gun stocks. The finish was glossy and looked like plastic. That was the look the customer wanted back then. Today I hand rub on the Tru-Oil and rub it back to kill the gloss with Rottenstone.

 

[Old-Duckman]

I hear ya Zug, a sprayed on Tru-Oil finish left unmolested does resemble a gloss urethane finish. In fact when I did a stock for someone who wanted that effect I finished my method by applying one or two coats of Tru-Oil via their spray can. This put on a thinner, even shiner finish than I could do with an airbrush.

Though I don't use rottenstone I do finish my Tru-Oil stocks to an eggshell, matt type of luster. I will post photos of the Scout stock when finished...I guess I should post that in this child board under a new post.

The attached photo is an unmentionable stock I did not too long ago (I hope this photo is allowed as the firearm type is indistinguishable). It is a beech wood stock that I stained with a red gel stain and the finish is Tru-Oil (with an added ingredient that I don't care to reveal).

 

[Nor Cal Mikie]

Tru-Oil put on with your finger tips, excess wiped off. Let it dry REAL GOOD.
Days if necessary.
Go after it with steel wool then do it again AND again if you so choose.
Makes a REAL GOOD sealer when taken down and shot with Automotive Clear when you got tired of looking at it and needed a new look.
Colors showed up on a laminated stock that I NEVER saw before.

 

[nhmoose]

I have used Tru-Oil Spray bomb. Worked well for clear bowling ball type finish.

However, it appears to be discontinued everywhere.

Never thought of using my air brush as I prefer a matte finish like a hand rubbed. I get that by apply a heavy coat then wiped off with a lint free cloth. It takes several coats to do.

 

[Old-Duckman]

I have used Tru-Oil Spray bomb. Worked well for clear bowling ball type finish.

However, it appears to be discontinued everywhere.

Yes I thought that was the case the last time I looked for some. It did lay down a smooth high gloss finish. Was very easy to get runs though.

 

[nhmoose]

The runs cut off easy with 4/0 steel wool than spray again. Thats how I did it.

 

[necchi]

Is "spraying" actually a time saving method to a good finish or just another technique?
If the power goes out at your house, will you still be able to achieve a good finish with Tru-oil?

 

[Old-Duckman]

I don’t know that I’d call it a time saving measure. I use the Tru-oil to fill the pores of the wood so it takes lots of coats to do that.

I know of wood fillers and of sanding in finish but this is the way I have done it for decades and I have been successful with it. I have tried both fillers and sanding in the finish but spraying is my preferred method.

Of course I could (and have) applied Tru-Oil by hand in fact if I am doing a quick job for someone I have used the hard application method but not to gain a finish where the pores of the stock are completely filled.

I am currently doing a buttstock, forend, and a stock for a Pedersoli Scout Carbine. I mix a 3:1 Tru-Oil to thinner and fill a 1 ounce bottle. I use all or nearly all of that bottle on these 3 pieces of wood each time I spray (1 sometimes twice in one day). So I am literally putting 3/4 ounce of Tru-Oil on these 3 pieces each time I spray. There is no way that you can lay that much finish on the wood, at one time, with the hand application method.

 

[necchi]

So you are using the product as "sprayed" for a commercial use?
I mean for multiple pieces, for multiple customers, to save time in application?

 

[Old-Duckman]

Years ago that was the case but now I do mostly for myself.

I would have to say that application time is slower when using the airbrush. Time involved in mixing and straining the finish/thinner and even more time cleaning the airbrush. When cleaning I also prepare a bottle for using the next day. It is much quicker simply scuffing down the previous coat and hand rubbing on a fresh coat.

Spraying isn’t for everyone, I wrote my original post for those who might want to consider doing so. Basically things I learned over the years using this method. The airbrush and compressor are not very expensive but more so than just using Tru-Oil and your fingers. If you are pleased with the method you use you might not want to go to the trouble and expense of the spraying method. If you aren’t extremely scrupulous in cleaning and caring for the airbrush and bottles you will have poor results and experience much frustration.

 

[boberator]

I am new to muzzle loaders but not new to firearms. I have finished and refinished gun stocks, grips etc for decades. Some things I have learned about spraying Tru-Oil might help others. This is going to be a long post.

I use a Paasche SI airbrush.
#3 Needle
The end of the needle protrudes from the back of the brush 1/4"
If you buy this brush also order 1 Oz. glass bottles (VL-1-OZ). The plastic bottles that come with a kit are junk, I use them only for holding naphtha for cleaning purposes.
Order a reamer (VL-54). Trust me you will end up needing it sooner or later.
I have 2 extra triggers on hand (SI-10), I will explain this later.

Years ago I used lacquer thinner to thin the Tru-Oil for spraying. I don't know when the formula changed but lacquer thinner no longer works, use Naphtha as thinner.

Process for preparing and spraying:

I put one to two coats of Tru-Oil on by hand scuffing down between coats.

I use 3M scuff pads not steel wool. I use the grey ones for most of the process but knock down in coarseness to the tan pads as the finish nears completion. [These pads are numbered for body work as 1 (maroon), 2 (gray) & 3 (tan), I get them from Amazon in a roll].

Scuff down the cured finish leaving no shiny areas.

I then dust off the stock with a good quality paint brush. Then hang the stock and use the airbrush (without a bottle attached) as an air gun to blow off the entire stock concentrating on "nook and crannies" you will see the dust being blown away from these areas. After this. lightly rub a tack cloth over the stock.

I use about a 3:1 (Tru-Oil to Naphtha) mixture. Strain the mixture through cheesecloth. This is important as thick Tru-oil will clog the airbrush and you will get a very limited amount of finish coming through the brush.

I use this compressor, purchased from Amazon, it is an excellent little compressor Amazon.com Set your regulator to 40 PSI with the trigger pressed.

I always trigger the brush off of the stock and then move to the stock to begin spraying. I stay approximately 8 to 10" from the stock.

Spray on a rather light coat as it is easy to get runs. Let the finish set (flash off the thinner) for 1/2 a minute or so and look over the stock. If your coat is too heavy it helps to hold the stock horizontal so that runs do not form. If runs have formed you can gently touch them with your finger tip and that will usually take care of them if they are not too large. At this point if you see any areas that need a bit more finish you can spay on more being careful to not over do it.

I then move the stock to my drying box, that is simply a wooden box with a 100W light bulb in it. Let cure overnight and repeat the process.

After 6 coats or so you will want to wet sand with 400 grit wet or dry paper. You will sand through the finish in places, don't worry as you will be finishing over those areas with plenty more coats of finish. Scuff down after sanding and apply another coat.

I like to have all the pores of my stocks filled and depending on the wood in question depends on how many coats you will need and if you will need to wet sand more than once.

Cleaning the airbrush: This may sound crazy and you wonder why I add it but a clean brush is critical to good results.

Once done applying finish trigger the brush to get any remaining finish out of the brush. Attach a bottle with straight naphtha and spray into a paper towel for several seconds. Unscrew the handle assembly from the body of the brush. Be careful as the trigger will no longer be attached to the brush and it is easy to lose (that is why I suggest that you have at least one extra trigger on hand).

Wipe the body of the brush with clean naphtha. Wipe the needle as well, this must be done after each use. Feel the needle and if it is not smooth for its entire exposed length, lightly clean it with 4-0 steel wool then re-wipe with clean naphtha. You can trigger the brush without the handle/needle assembly attached but you have to insert the trigger to do so.

Carefully reinstall the handle/needle assembly, the trigger must be placed in the brush prior. I make sure that I have a good view/light as I look into the back end of the brush to insert the needle. The tip of the needle is very fine and a heavy hand here can damage the needle. I keep extra needles, tips, O-rings and triggers on hand.

I wear a respirator during the whole spraying and cleaning process!

I hope this lengthy post might help those who might want to spray Tru-Oil.

Very well written instructions. I’ve never used my airbrush for applying Tru-oil but if I want to, you have written the textbook.

 

[user 34300]

I have sprayed a lot of stocks, I no longer do so. With wood, particularly walnut, the grain will soak in the finish. When I sprayed on finish I got material floating on the surface and pinholes where it soaked into the grain. IF I placed the stock in the sun to dry the pores blew bubbles n the finish. So, I made a hot box to preheat the stock and push air out of the pores. I then sprayed the stock as it cooled. That pulled the finish into the pores more and no bubbles, still no even filled coverage. The final way to spray a stock involved filling the grain with paste filler. Then heating the stock to be warm, maybe 110*F. I then sprayed with fuller-plast or glasscote. As the finish was pulled into the grain I woule let the solvent flash off and put another layer until it looked slick. That resulted in a stock was looked like a Weatherby in one session. This is not appropriate for a ML.


I mostly finish maple now. Thinned coats of wiped on spar varnish works great for me. About four coats is usually enough. I am not looking to build a finish on the wood as I was when I sprayed stocks. I want the film on the surface to be minimal.

They used to make rattle can True Oil. I never got a finish I was happy with using it.