Softness of Oil Finish

Joe

I assume this is the Mannlicher walnut stock mentioned in your earlier post?

And, these are the directions included with the Genuine Oil?




Are you allowing max drying time between applications? Are the applications very thin?

Yes, that a pretty low temp for this work.

I use a pvc sewer- sized pipe (12’ diameter maybe) with a light bulb in the bottom. I put a piece of 1/2 plywood drilled full of holes over the bulb to diffuse the heat. Buy a cap for the top of the pipe. Cut a rectangle in the side which will allow stocks to go in easily. Hanging rod through the pipe up near the top. Get heavy plastic and cut several pieces that overlay each other to cover the hole - like you see in some warehouses. This curtain lets you get in but keeps out floating stuff. Spray down inside with water and wipe down before a job to get the dust out of the pipe. Most all of floating crap problems will go away and especially bigger floaty crap plus you get a constant temp. I put a thermometer in to monitor the heat. I have two sockets in the bottom so I can add another bulb if needed. Surprising how much heat a light bulb will give off.

You may be able to rig your set-up similar.

When you have blends which are inevitable, don’t sand down so much. Really all you want to do is smooth out the blemish and give some tooth to the surrounding dried finish for the next coat to grab onto.

This is the only place I might go to steel wool and use it very gently. Just get some light scratches for tooth.

Smoothing with 3M car glaze paste does wonders with small stuff when you’re done and before final polish.

Hope this helps.

My concern is if the under coats were not dried, it may take months to harden up. The outer coats sealing the voc's in so it want dry and harden. I hope I'm wrong on this one.

My rule of thumb for finishing any wood, if I can smell the previous finish, it is not ready for the next coat.

Kevin

Move it inside where it's warm. Or find a heat lamp and let it work at a distance. If you have a ice chest big enough store it in it with a small 25w light bulb and see where the temp goes.

I had a ultra low unit that was used for artic testing, 12'x12'x10'. 2 150w spot lights would heat the box to over 100F in 12 hr.

sign216 said:

… continue the finishing, with a new bottle of oil, since the old one is past prime (that might be negative factor too)...

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Anytime I open a container of finish, I write the date on it. If I have not used it up with 12 months, it goes in the trash. I put too much work into something to have to redo it because the finish is old.

Kevin

sign216 said:

My oil finish, not yet done, is fairly soft and easily scratched. A couple of times I've had to sand out errant marks, which brings me back a few steps in the finishing process. When I am done, and the finish aged, will it harden?

I am finishing a new stock with a tung oil + solvent mix, Genuine Oil from Birchwood Casey. Stock is Amer. walnut, and the raw wood is plenty hard, but with a few thin coats of oil, it seems soft. Thumb nails leaves a good dent when I'm trying to burnish out scratches (oops), and accidentally hitting a table edge does too. After I'm done with the oil coats, and allowed to set for a month, will it harden up, or is there a problem?

Joe

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In all honesty ... NOPE !
It will slowly get somewhat harder but not as hard as a Varnish or as hard as Min-Wax Tung Oil Finish .
Varnishes are Linseed oil based with added hardeners and driers and such to form a hard finish .
Min-Wax Tung Oil Finish is similar to Varnish but with a Tung Oil Base .
Tung oil + solvent has no hardener or oxidizer but the drier (solvent) will help ... it will actually give you a good looking , water proof finish ... it will be slow to dry , so give it plenty of time ... or complete the job with Min-Wax Tung Oil Finish ... this product will get harder ... and looks good! that is easy to touch up if marred or scratched... and it is easy to simply rub in a thin coat of oil , by hand , at the end of each hunting seaon to keep it looking good .
The oil + solvent won't be the hardest finish but it will be pretty and will be a nice classic finish .
If your Tung Oil + solvent isn't hardening ... You may want to really think about completing the job with the harder Min-Wax Tung Oil Finish ... I have refinished not only gunstocks with it but antique oak dining room tables and chairs ... the stuff dries nicely .

The old adage for a hand rubbed oil stock finish was... rub in a thin coat every day for a week .
Then rub in one coat every week for a month ... then rub in one coat each month for a year and then ...
rub in one coat every year ... for the rest of your life !

Gary

I have seen enough of this thread to offer my opinion: When one buys a factory finished long gun, the stock finish is never soft (at least during the last 50 years of my experience). The factories use finishes which harden within a couple days (if that long). They cannot afford to do otherwise. Nowadays most use a two-part finish which hardens when mixed. Anyone could do the same thing if they wanted to buy 5 gallons of the finish and its hardener. But we don't need so much to do a stock or two. The best alternative is a polyurethane finish which can be found at most hardware stores and lumber yards. The most reliable is stuff similar or identical to Minwax poly finish. When I used to make furniture I used it, and never got a complaint. And it was independently reviewed by a couple woodworking mags as the most durable, over everything else, including linseed, tung, shellac, etc.

sign216 said:

I'm hoping the 24" rod, with the 12", will bring temps up to 70F mark. That should allow for a good cure. NMexJim, nice set up you have. What temps are you getting?

Re the sanding, I don't sand between coats. Just saw some blemishes I want to resolve. But, the softness of the finish can make new bumps (arrgh). The car glaze paste is an interesting idea, but I didn't fill/wet sand the stock, so the grain's pores are open. The paste might not work well there.

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Whoops, don’t use the paste until the finish is complete. It’ll polish out small blemishes only.

I try to keep heat around 75 although I’ve seen as high as 80.

You should lightly sand, more scuff than sand, between coats if the coats are getting hard. Otherwise you may not get one coat to ”grab“ the next. That’s the “tooth” I’ve mentioned before.

You should not be applying a new coat until the last coat is dry - no less than 24-hrs and more like 48. Coats have to be allowed to “gas off“ which is the solvents gassing off leaving behind the solids. If the costs aren’t dry in between, I wouldn’t be surprised your finish is soft.

Chug-a-lug and my ears still rings. Wow, I did read this although I have to admit I have some dents in my forehead from where I fell slap asleep several times and banged it on the desk. I kept looking for them to increase the dryers past 1% and what those results would be, but might have missed that. Anyway, interesting.

So, here is a more typical depiction of boiled (polymerized) linseed oil. This clip from Obsessedwoodworking.com, but I found others very similar.



So, every instruction for the application of linseed or tung oil as a gunstock finish includes specifics about thin coats rubbed well in. All excess oil to be wiped off. You might remember my suggestion that it be applied warm "nearly hot to the touch" (or maybe that was another thread) to get deeper penetration plus when the rubbed-in oil became "sticky" to palm the surface in line with the wood grain to not get swirls in the finish.

Add dryers (no, I don't know the percent) and get faster results, i.e. Genuine Oil or Tru-Oil.

I have to lay the cause of your issues at the feet of temperature (or perhaps too thick). Heat lamps maybe. I haven't tried those.

Somewhere I posted that I had gone to a spray-on stock finish (although I have used their oil products as well) shown below. To keep dust down with a spray, you have to have a tube like I described. And, this is still a process that can take up to 10 coats.

I feel your pain. My first few were a trial and steep learning curve.

Besides my previous comment about the polyurethane finish, I suggest that waiting the entire spring/summer (for some oil finish) just might be longer that most might expect for a finish to fully cure. I have applied seven coats of the poly to a special gift I made to my wife, and it is just shy of bulletproof (with two-day curing times between coats). Again, no complaints about all the furniture I made/finished with it, from any customers. Plus, all my household furniture I made is extremely durable. Sometimes the past might just be time to let go.

sign216 said:

NMexJim, you made me laugh. Like you, I really wanted them to add more than 1% drier.
Beag nut and all,
I think my problem was the 60F temp. Even though the finish looked good and was no longer wet, it was never curing in the 48hrs between coats. I don't think thickness was an issue, as I was rubbing in a few drops at a time. Even so, next time I'll go even lighter.


In a prior thread, board member Mizar found that Genuine Oil is about 50% naptha solvent, 50% tung oil.

Hopefully a month in the the hot box will cure it. We'll see.

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Well, maybe check on the progress every now and then.

Yes, I read Mizar's post.

Here's the Chem Pac oil product that I've used. Worked great as a rub-in. I admit to using gloves to work it in.


Years back I was able to talk w/ the gentleman that formulated all of the Chem Pac gun stuff. His business was packaging soluble products for other companies but happened to be a gun nut. I tried the spray and ordered a case of both gloss and satin (no gloss anymore). I've still got a can or two. Happy to send you one if you PM your address to me.