Some Questions About Oil Finish (danish Or Tru)

[ShadesOfGrey]

I'm in the planning stages for my next project, which will be the first from scratch build I will be attempting.

Due to the hassle and problems I had with a block spray finish on my kit build, I'm thinking about just doing a natural finish by oil.

One challenge at a time, right?

But there's some things I need some clarification on..

The build will most likely be a mahagony body, and the oil will be danish oil (as I have a nearly full bottle lying around).

Will I need filler or sealer for the mahagony? Or will the oil act as filler in itself?

Secondly, I want to have a headstock decal of my own design.

Most methods seem to be either a vinyl sticker or waterslide, but I'm not sure if the oil finish will work with that as I've been told that the oild needs to make contact with the wood or would otherwise flake off. Does anyone have experiences with decals + oil finish or suggestions?

And kinda related, I want to shield the cavities. I have a big roll of aluminium shielding tape, but I dont think it has staying power on top of the oil finish. In reverse, I dont think the oil will stick on top of the tape. So I guess I need to find something like copper paint and leave the cavities oil free?

I cant think of anything else right now, but if anyone has input / suggestions / tips / issues / things to look out for when doing a whole guitar in oil vs. only the neck, I would be very gratefull

[ScottR]

Danish oil will not build up a film like tru oil can. So if you are using Danish and do not want visible pores, you'll need a grain filler, although many use Danish to keep the wood looking as natural as possible and so do not fill the pores at all. Do not seal the wood first or it will not absorb the oil...which is kind of the whole point of an oil finish. Once the oil has cured, a vinyl decal will stick fine to either. Water spots a Danish oil finish, so I would not recommend a water slide on that. I do not know what it does to tru oil...but my gun stocks clean up nicely after being rained on.

SR

[ShadesOfGrey]

I dont mind visible pores, more a case of economics.. I'd rather not have bucketloads of oil getting sucked into the huge mahagony pores. I was wondering if this works the same as laquer, or that oil penetrates a bit but is less 'fluid' in a way.

Once the oil has cured, a vinyl decal will stick fine to either.

So you put the finish *under* the decal? I thought it was the other way around

A waterslide wouldn't be very longlasting without finish on top, and a vinyl decal wont look very good. But if that is the only way without resolving to laquer

[ScottR]

Since Tru Oil crates a film you could possibly apply more of that over the decal...I have never tried, but they may be some that can speak to that. I have used Danish oil quite a bit and it will not build up a film or affer any kind of protection over a decal. It will soak into the wood and cure there and look really nice but will not offer a great deal of protection.

SR

[pauliemc]

The whole back & neck on this guitar are done with Danish oil http://projectguitar.ibforums.com/index.ph...=43332&st=0

I sanded it to 4000 grit (min) then used 000 grade steel wool to buff it up, Then applied the oil using an egyptian cotton cloth for the first 3 coats.

Waited 3 days. then I applied a further 3 with scotch brite steel polishing pads,

Waited 3 days, Then a final buff with grade 000 steel wool & a light coat of danish.

Waited about a week, then buffed it all up with a cotton cloth.

Comes out fantastic. Then neck feel amazing done this way.

[Quarter]

I've buried waterslides under True Oil just fine. As was mentioned, TO will build a film thickness and cam be lightly wet sanded and leveled.

If your set on a simple Danish oil, you might re think the logo, lots of cool things you can do other than waterslide or decals. Engraved, inlayed, laser etched. use a branding iron, molded, cast, metal. plastic, colored epoxy ......

[ShadesOfGrey]

I've buried waterslides under True Oil just fine. As was mentioned, TO will build a film thickness and cam be lightly wet sanded and leveled.

If your set on a simple Danish oil, you might re think the logo, lots of cool things you can do other than waterslide or decals. Engraved, inlayed, laser etched. use a branding iron, molded, cast, metal. plastic, colored epoxy ......

I've contemplated branding too. I have a heatgun laying around that I could use to warm up a branding iron.

Thing is, I dont want to do something too involving as the reason I'm going for an oil finish is that it's going to be my first from scratch build.

I'm not dead set on using danish over thru though.. it's just what is available. I'm not realy sure where I can find an importer for that here.

[Geo]

And kinda related, I want to shield the cavities. I have a big roll of aluminium shielding tape, but I dont think it has staying power on top of the oil finish. In reverse, I dont think the oil will stick on top of the tape. So I guess I need to find something like copper paint and leave the cavities oil free?

Just leave the cavities unfinished, then you don't have to worry about whether the tape will stick or not.

[wang]

Thank you for sharing

[ShadesOfGrey]

And kinda related, I want to shield the cavities. I have a big roll of aluminium shielding tape, but I dont think it has staying power on top of the oil finish. In reverse, I dont think the oil will stick on top of the tape. So I guess I need to find something like copper paint and leave the cavities oil free?

Just leave the cavities unfinished, then you don't have to worry about whether the tape will stick or not.

That's a possibility, but unfinished means less stable because more moisture can move in&out right?

But yeah, an aquantance of mine told me he finishes using 'Rustins Plastic Coating'. Is that stuff any good for finishing bare wood on guitars? I might try that instead and only oil the neck, but I tend to stick with what I know so..

[Geo]

That's a possibility, but unfinished means less stable because more moisture can move in&out right?

I don't think that should matter on a solidbody. If you were leaving, say, the endgrain of the neck unfinished, that might be a concern.

I've always left the cavities in solid bodies and the interiors of chambered solidbodies (with F-holes) unfinished. I've never had any problems, but then again, my guitars are only a few years old at this point.

[Mattia]

It really won't be a concern, even for the end-grain on a neck.

Acoustic guitars have thin plates that are only finished on one side, and they hold up fine. Pretty much every single acoustic bolt-on neck joint area (all joining surfaces, mostly end-grain) are left unfinished, and they work out fine.

Besides, most finishes don't really block moisture all that well, including nitro and most varnishes (ie tru oil).

[verhoevenc]

Most finishes merely SLOW the reaction of the wood to moisture in the environment. The wood will eventually change. But slowly the rate reduces warping, checking, cracking, etc. That's why it's desirable. THAT SAID, on a piece that's already dried, leaving stuff open should NOT be an issue! I mean... if it IS I better kiss my wood stash sitting on the shelves goodbye hahaha.

Chris