To finish, or not to finish, that is the Question!

[G7MOF]

I have a beautiful natural wood none finished mandolin, spruce top rosewood back and sides with a powerful voice. Already the mandolin is starting to look more like a beater than an expensive mandolin and my question is, If I were to laquer the back and sides and leave the top unfinished would I lose any tone/volume and If I were to laquer the top as well would I then lose tone/volume?

[multidon]

You have to have some kind of finish on there to protect the wood. Instruments left white just get grubby looking from dirt and handling. If you keep the finish thin, there will be no loss of tone or volume at all. Problem with lacquer is you can be tempted to put on too many coats because it just looks so nice. If you want to keep the finish as thin and organic as possible why not just a couple of light coats of shellac? It would not change the appearance of the wood much from what it is now but you would have the protection from dirt.

[bayAreaDude]

You could do a few coats of tru oil too. You can get good protection while keeping it very, very thin and it's easy to apply.

[TEvans]

I built a bass guitar a few years back, and used true oil straight on the walnut (after a grain filler) that looks beautiful. If you want minimal finish that still protects the wood, tru oil is a good option. I mean, it's gunstock finish....So if you are worried about it not being protective...think about the abuse that a gunstock will go through in the field...

I would recommend it!!

[G7MOF]

Thanks I'll give true oil or the equivalent UK oil a go.

[Mandobart]

I use tung or linseed oil on my mandolin and fiddle necks. Very nice thin yet protective finish, can be hand buffed to look nice (but not glossy). And it feels great on the neck. I confess I like the smell of linseed oil...

[DHopkins]

I always use tung oil on my dulcimers. It produces a bit of a gloss, is easy to work with and is inexpensive. I usually put on at least 6 coats, each followed by a rub-down with 0000 steel wool. I know that may sound like a lot but it's not. It goes on easy and I love the finish it leaves.

[G7MOF]

Will this harden the finish as it's the tiny scratches and very small dings I'm trying to avoid if at all possible!

[DHopkins]

Tung oil will not provide much protection against scratches and dings and won't fill them, either. It's liquid water resistant but it doesn't seal well enough to prevent water vapor effects. I cures to a light golden finish.

[TEvans]

The Tru Oil is a bit tougher than straight up tung oil, in my experience. It is definitely a thicker consistency when applying it, and seems to dry into a sturdy protective layer. It has shielded my bass quite well. I think I applied about 8 coats of it.

Also, if I remember correct, I purchased it through a luthier website, but they carry it on Amazon, as well. http://www.amazon.com/Birchwood-Casey-Tru-Stock-Finish/dp/B002JD3J2M

[multidon]

Let'smake sure we are comparing apples to apples. Use the search function to find some of the old finishing threads.

Therr is a lot of confusion about tung oil. I use 100 percent pure tung oil on some of my necks. Leaves them with a nice smooth bare wood feel and kerps out dirtbut as noted above also does not protect well against scratches and dings. But there is also a variety of different "tung oil finishes" out there. These are concoctions of oil, varnish, and solvents that are basically wipe on finishes. Formby's is a perfect example. There are others. On woodworking sites there are even recipes for making your own wiping finishes. Usually they contain linseed or tung oil, oil varnish, and mineral spirits. People are often surprised when they find out Formby's Tung Oil Finish likey contains no tung oil. So how can they call it that? Marketing. That being said a finish like that is much more protective than pure tung oil because of the varnish component.

Now Tru Oil is basically a linseed oil wipe on finish. Its main components are boiled linseed oil and mineral spirits. It also contains other oils they don't disclose. Linseed oil has been used as finish for a long time. It has the property of self polymerizing. In other words it forms chains of molecules that cause its physical characteristics to resemble a plastic. Oxygen and sunlight exposure speed the process along. Although Tru Oil dries enough to apply a new coat in a few hours I find it does not fully cure for several days at least. A couple of weeks is better. At that point it becomes quite hard and protective. It seems quite resistant to scratches. Hope all this helps.

[Steve Zawacki]

If the finish becomes "hard and protective," will that also negatively affect vibration and tone?

[bayAreaDude]

I don't it's possible get a hard candy like finish ala laquer using Tru Oil. I applied maybe 25 coats to a solid body electric recently with 0000 steel wool after about every 4 coats. It's very glossy and protected, but I wouldn't call it hard and I've already got a couple dings.

[multidon]

If the finish becomes "hard and protective," will that also negatively affect vibration and tone?

No. The trick is to keep it thin. If it is thin enough it really doesn't matter even what type it is. Finish just doesn't add enough mass to significantly affect tone. I know this is highly controversial around here and there are those who swear they can tell the difference between, say, varnish and lacquer. Let's just say I have my doubts.

[GKWilson]

Never put a finish on a mandolin. But, I have built flintlock rifles and finished them with Tru-Oil.
The trick is to put on a light coat first then add just a drop or two a day till you get the coverage you want.
This should give you a thin harder finish.
Several heavy coats will leave you with a thicker, softer, finish. And, will take a long time to fully cure.
I would think wood is wood. But, as I've said I'm no luthier.
Gary