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Still trying different finishing techniques for my first build, an Indian rosewood and sitka 000 12 fret. How many coats? What are the steps? How much will I need? Any hot tips? And thanks again.

Try searching for Mya Moe Ukulele , The birth of a Mya Moe(I think it's called something like that). There is a particular video which describes their technique. Their ukes only have around 4 coats, but you could apply many more depending on how glossy you want it. Basically, apply with a blue shop paper towel and then wipe it all off again. Re-apply and repeat and the more you do, the glossier the look. It might sound strange to wipe it all off each time, but that is the key to a slowly built but consistent finish. A light rubbing with 0000 steel wool in between coats may help.
There are other ways to do this, but it was the method I used before I changed to laquer.
https://www.youtube.com/watch?v=ccQ1b3S1rWk, use their channel to search out the previous episodes if necessary.

I like to use 400 sandpaper on the tops but steel wool on body and neck. There are some who think an oil finish deadens the soundboard. I also did. few instruments where I used a shellac to seal the top first. I don't have a preference either way

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The approach depends on whether you are going for a bare wood, satin finish, open pore look - or a smooth as glass, super glossy, factory made guitar look. If the former (which is my preference, and definitely a recommendation for your first build) you would sand everything to about 400 grit and then apply Tru Oil (or any hard wax oil) as described above. It will start to look good after the first coat but will be better after about four, which is when you can stop. Give it a light sand with 400 or fine steel wool after coat 3. If you want the factory style super glossy effect you will need to fill the pores, prep the surface meticulously, and build up something like 25 to 30 coats of oil to get a surface that you can level and then polish laboriously with finer and finer grits and then polishing compound.
Tru Oil is very economical as you use tiny amounts. If you are doing method 1 that I described a small bottle would be enough for maybe 3 instruments - except that the stuff skins over and will dry up in the bottle long before you get number 2 and 3 built!
My hot tip, which I think I read here but I can’t remember who to credit for it - the stuff lasts better in an open bottle if you get most of the air out by filling the dead space with inert objects like ball bearings or glass marbles which you drop in one-by-one as you use the oil up. Good luck with it and with your build. Make sure you show us the result.

I turn the bottle upside down when storing--It skins over at the bottom of the bottle instead of the top this way. Of course, remember to turn it rightside up before you open it!

LMI had a great article about oil finishes for guitars years ago in their big handbook. The bottom line for me, whether Tru Oil or any other oil type finish is that the finish will never be better than the surface you start with. Unlike real "oil finishes," Tru Oil builds, but not like lacquer or varnish. I've used it a lot and like it. But I sand way past 400--I'll take it all the way through all of the micromesh grits. Any scratches (even 400 or 800 grit scratches) left on the surface will show up pretty obviously. If the pre-finish surface is perfect, the finish will be great.

I have a buddy who is also a banjo maker who sprays Tru Oil. Done this way, it behaves more like a lacquer finish and can hide some of the fine scratches. It gums up spray guns pretty bad--he buys the cheap Harbor Freight door jam guns and throws them away when he can't get them clean any more.

Dave

I'm hoping for a warm gloss, not super glossy, if you know what I mean, so I'm willing to do some grain filling. What kind of grain fill would be best?

A other option is osmo if you’re looking for something pretty cool proof::)


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Store the bottle upside down - now that is pure genius!

Asking for suggestions about pore filling? You have just opened a whole can of worms. My 2c worth is just don't fill the pores. I like wood to look and feel like wood, and not a pane of glass. But I acknowledge that I am in a small minority with this opinion and if I was trying to make a living selling my guitars I would go broke unless I sold shiny glossy ones.

And I agree about Osmo (or other brands of hard wax oil). It is now my favourite, over Tru Oil. It is fool proof - but also cool proof?

I like open pore, but for pore filling with Tru Oil, I'd put on a coat of Tru Oil and then sand it out while it's wet with 800 grit or so. The slurry would fill the pores. Took several times but works well.

Dave

I use TruOil a lot and like it for the most part.

Am I the only one who has trouble with TOil over oily woods like rosewoods? Why don't folks mention the problem applying over oily wood?

One of the most important things for me when using TOil over oily woods is to make sure you have a barrier coat of shellac before the TO.

Oil varnishes just don't seem to cure/dry well over oily woods. So, do a pore fill or 3-4. Then do a couple coats of shellac as a barrier coat between the oily wood and the TOil. Even if you sand thru the barrier coat on an edge or something, the darn TO (or other oil varnishes may NOT dry!).

Nothing worse than finishes that do not dry.

I like epoxy pore fill, current favorite is Silver Tip but had good success with Z-poxy too.

As others have said, get the surface perfect before starting with TOil. If you think you are done with pore fill do it one more time!

Yea, TEST your TOil over your project before applying to the whole git!

BR

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Brian R, Wood Mechanic
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I like Glue Boost for Pore Fill then a shellac wash coat then true oil

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Some people apply tru oil with their finger tips.

I've read on another site that sometimes the oils in rosewood might leach out and cause problems in spots. That's worrisome, not knowing. Thanks for all the info.

If you know you're working with oily woods, clean them very well with multiple cleaning fluids. Think denatured alcohol, lacquer thinner, etc. I do that anyway before gluing a rosewood fingerboard on a neck. Don't be shy - keep working until your cloth is clean. Then come back a couple days later and do it again. Any kind of resinous wood - I even clean cherry.

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Concentrated dish detergent pulls oils out surprisingly well - even better than many solvents.

Dawn, right?

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So far for me, once an oil finish dries it's good to go and I've never heard of problems with oil finishes softening or getting gummy once they have dried from oil in the wood beneath.

I've wiped oily wood with solvent just prior to gluing. I've also just refreshed the glue surface with a plane or scraper. Both worked for me. Opinions vary on the best approach.

I've also heard of wiping with solvent prior to finishing as Chris suggested. The problem with that for me has been the solvents pull color out of the wood with the oil and it seemed to detract from the wood. It can stain lighter wood if not careful.

Many of the exotics have oily characteristics. I've run into problems with ebony, macassar, bocote, ziricote, teak, padauk, etc. Even just an ebony binding for example.

The easiest fix for me is to just wipe on a couple coats of dewaxed shellac prior to an oil finish. If you happen to sand thru an edge and the finish gets sticky I just wipe it off and apply a little shellac with a fingertip and you can usually continue on once dry.

Lots of ways to make it happen.

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Brian R, Wood Mechanic
N8ZED

Here is a Tenor Ukulele I built 18 years ago and finished with Tru-Oil. The wood is figured Mohogany. No pore filling other than Tru-Oil. Hand rubbed with T-shirt material. I believe it was 6 or 7 coats. Extremely easy to work with. Finished with full series of micromesh. Sorry for the photo, it is the only one I have at the moment.
Best of luck!
Philip

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If you think my playing is bad you should hear me sing!
Practice breeds confidence and confidence breeds competence. Unfortunately, I'm stuck in practice.

Yeah! Works on ducks too.
Liquid laundry detergent would probably work too, but I haven't tried that yet.
The detergent will pull the "color" out of the wood some, but that may be a plus with woods like cocobolo. Cocobolo turns dark under finish as the oils darken. I like the color before it goes black, and removing some of the surface oils may retard that tendency, at least for awhile.

Dish soap on wood surface before gluing sounds counterintuitive. Assuming you are cleaning it with water afterwards, but couldn't it still be in the pores? Seems like surfactants might affect glueing.

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Pat

I always wash off the surface thoroughly and allow it to dry well. Dish soap and laundry detergent seem to be made to rinse out relatively easily says the "un-employed bum" (as my friend's wife calls us) who cooks dinner, does the dishes, and washes the clothes for my hard working wife. I think it leaves a surface better for gluing than what most solvents leave, but that is an opinion with no scientific validation.
I did a little test this morning on Dawn dish soap vs. Laundry detergent - I didn't notice much difference on the "oily" piece of tropical hardwood I tested it on. Both detergents removed the surface oils from the test piece.

The test piece is as dark as the picture with the detergent bottles. The camera "overexposed" the picture of the sample, but it does show where the oil was removed.

I have finished necks with TruOil and one Uke. I followed tips Addam Stark gave me a long time ago as well as the article in the old ring bound LMI catalogue. I polished the wood up to 800G and then micromesh. Checked carefully for scratches with naphtha. I seemed like on a Mahogany neck the fine sanding filled the pores and the first coat of Tru Oil sealed it in so it looked pretty good.

It has been mentioned here in the past but I had several necks on which I used Z Poxy for pore fill and put the Tru Oil on right over it. They all got fuzzy after a time and you could steel wool them smooth and they would just get fuzzy again. Only solution was to sand off everything and start over. Something about amines leaching out of the epoxy was mentioned.

Anyway I quit using ZPoxy under Tru Oil and all was well. I think the surface prep-polishing the wood first is probably the most important thing.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

I've got a few instruments out there with ZPoxy pore fill and TOil over as a top coat. Some 15+ yrs out with no problems.

I always apply a couple coats of dewaxed shellac to provide a barrier over oily wood. Maybe it was the shellac that prevented the fuzz. But, I don't understand why epoxy (Z or otherwise) and TOil would make that happen.

Have also read articles the occasional amine blush of ZPoxy may be a humidity issue as it can be with nitro.

This should be a good thread on TOil for reference. I thank everyone for the input.

Those of us w/o a spray booth in our futures appreciate "brushable" alternatives.

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Brian R, Wood Mechanic
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I just use two or three coats of Tru-Oil on necks. This monkey pod back has four coats. Looks great and feels like wood. The depth of figure that came out is astonishing.

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Pat

What works for me, when pore filling, is a couple coats of 2 lb shellac. Then use a french polish pad loaded with Everclear and work the surface over with pumice. The pumice and shellac makes a good pore filler. It is labor intensive, but works for me.