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Polyurethane over oil stain....still tacky!


sinebar1
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There are too many unknowns with various household "hardware" finishing products. All of the notes above are legit, but apply to different scenarios, not as clear cut as we would like it to be.

I can't broadly say that all Minwax or miscellaneous canned finishes with muffle the sound, or that all finishes will be too opaque, or that all finishes will have extended drying times and not last.

I can say that Minwax one-step (stain and finish) products should never ever be use on instruments.

Putting an oil based product, even in small amounts (stain as the example here), underneath a shellac coat doesn't make any sense in terms of long term durability. It's kind of like putting latex paint on top of oil based paint... perhaps I'm wrong, but I think that it will fail, flake and peel eventually, even if most of the oil based product was removed before going to the next coat.

It's hard to go against the grain of the very well tested traditions. The violin world is not a hostile one, unless you simply believe it to be, or have no intent of learning new seemingly difficult things. Every step of the process is special. It's a bigger mind an money investment than most people like to make. I still have a bit more mind that needs investing. At the same time, I don't like being lumped in with rigid traditionalists, if you can find a good finish some other way, go for it.

As for kits... they exist... I do not know where.

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As I've said before, I'm not an expert, but here's my suggestion for simple. Start with a coat or two of thinned, de-waxed shellac (seal-coat). Smooth/sand lightly to eliminate any fuzzy bits, dirt, or grain. For top coats, try Behlen's Master Violin Varnish (spirit) ($21/pint from Grizzly.com). Use some soluble dye (like Trans-tint, or soluble dyes from a violin supplier like Int. Violin Co.) to get the color you want (mix colors if necessary, and test on scrap wood). Only put dye in a couple of ounces of varnish in a jar, so that you don't commit the whole pint! Add color coats to build up to the appropriate density. Sand very lightly between coats to get rid of dust particles, etc..

After you get the appropriate color density, add a couple of coats of undyed varnish to seal everything. Rub out the final surface a bit to smooth. Some people don't like the Behlen's varnish, but I think it's OK, and it's affordable.

Any other suggestions from other members?

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As I've said before, I'm not an expert, but here's my suggestion for simple. Start with a coat or two of thinned, de-waxed shellac (seal-coat). Smooth/sand lightly to eliminate any fuzzy bits, dirt, or grain. For top coats, try Behlen's Master Violin Varnish (spirit) ($21/pint from Grizzly.com). Use some soluble dye (like Trans-tint, or soluble dyes from a violin supplier like Int. Violin Co.) to get the color you want (mix colors if necessary, and test on scrap wood). Only put dye in a couple of ounces of varnish in a jar, so that you don't commit the whole pint! Add color coats to build up to the appropriate density. Sand very lightly between coats to get rid of dust particles, etc..

After you get the appropriate color density, add a couple of coats of undyed varnish to seal everything. Rub out the final surface a bit to smooth. Some people don't like the Behlen's varnish, but I think it's OK, and it's affordable.

Any other suggestions from other members?

That sounds like a good plan to me. It's simple and I'm going to follow it on my next fiddle. Thanks! :)

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  • 3 weeks later...
however by applying to a size coat....the stain will not actually be penetrating into the wood surface....only the pigments will "hot coat" into the surface of the wax free shellac and the deeper wood pits/pores....thus rendering the material colored with a semi transparent stain on the surface of the shellac....not in the wood itself....

so now lets look at this some more....

at this point what we are doing is taking a liquid vehicle, with very minimal solids, with color pigments and applying to the surface of an already sealed wood...

but the bottom line is that AS LONG AS MR. SINE WIPED OFF THE STAIN COMPLETLEY after applying it...that it is no different using minwax stain vrs. some red/brown natural goo you and your sherpas whipped up on the mountain top....

Hi Jezzupe, I'm a little slow here. If he wiped off the stain completely after applying it, then would he get any color from the stain at all? I don't see how the stain would get through the shellac to the deeper wood pits/pores, is that what "hot coat" means? How long should he leave the stain on before wiping it all off completely? Don't worry, no violin in question. Just learning about wood finishing.

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Hi Jezzupe, I'm a little slow here. If he wiped off the stain completely after applying it, then would he get any color from the stain at all? I don't see how the stain would get through the shellac to the deeper wood pits/pores, is that what "hot coat" means? How long should he leave the stain on before wiping it all off completely? Don't worry, no violin in question. Just learning about wood finishing.

Sizing, what this does,if the solution of shellac is nice and thin, is to prevent over absorption into the wood grain.If we took a piece of maple say and prepared the final wood surface preparation, regardless of if it be sanded or scraped and the coated only half with the shellac and left the other half raw and then stained this....what we would see is that the raw wood would be much darker than the half with the shellac, so yes it would dramatically reduce the stains absorption, the stain will be mostly sitting on the shellac barring some penetration into the larger open pours that may have been to big for the shellac to fill up and or seal off.The company has sold this as a product that is intended to be applied to raw wood, so that is what the color representation would be, however if you wanted to have the stain"raw wood" colored on a sized coat, you would be best picking a stain color that is WAY darker as the size coat will prevent the absorption.

So in simple terms

1. size coats will make dark stains take lighter, they are not in the wood grain, they are on the initial shellac coat, depending on how thik your shellac coat is will also determine how much stain can weep into pores

2.if you want dark colors on top of a size coat you will need to use very dark stains that would almost look black on raw wood

3.stain should be applied in sections, the back, then the ribs, then the front, I allow about one minute prior to wiping the stain off, waiting too long will make it difficult to remove, it will become sticky

Always do test panels to practice, do not practice on pieces ready for finish, get your system down, then approach your woodwork, it is far easier to work confidently once you have achieved a level of predictability and confidence

Edit:

"Hot coating" is applying finish,regardless of its base on a previously applied coat WITHOUT abrasion.It must be done while the coat you are trying to "hot coat" is still uncured, it relates to inner coat adhesion

An example

Apply one coat of wax free shellac, wait 45 min without abrasion,then apply a coat of oil base polyurethane, because the shellac is wax free and because we did not allow it to "cure" it is still slightly chemically soft, when we apply the poly, even though it is of a dissimilar base, it will chemically weld into the shellac coat and in essence the will become one....

If we waited say 2 months for the shellac to dry and then applied the poly, the poly would stick but would be much more susceptible to adhesion failure down the road as the shellac was not soft and uncured when we applied the poly, it had become "crispy" and will not allow for the poly to "weld", the two are now not one....not good

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Thanks a lot jezzupe for the explanation. I will try it on test pieces. I have a dulcimer I'm making with mahogany and spruce. Usually I do not put any stain on it, just dewaxed shellac washcoat followed by 4-5 coats of Waterlox oil varnish. But I was curious about adding some color. One guy said to put a small amount of asphaltum into the Waterlox. However he's probably assuming no sealer coat of shellac, as he uses straight tung oil with the asphaltum. I don't want too much "stain" per se, but to pop the grain nicely.

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Thanks a lot jezzupe for the explanation. I will try it on test pieces. I have a dulcimer I'm making with mahogany and spruce. Usually I do not put any stain on it, just dewaxed shellac washcoat followed by 4-5 coats of Waterlox oil varnish. But I was curious about adding some color. One guy said to put a small amount of asphaltum into the Waterlox. However he's probably assuming no sealer coat of shellac, as he uses straight tung oil with the asphaltum. I don't want too much "stain" per se, but to pop the grain nicely.

Waterlox is a tung oil with modified phenolic resins{a bakelite derivative} I am very familiar with this product. Generally i do not recommend this, but waterlox is proven "safe" to add stain to to tint it. So you may apply the stain to a size coat as previously described, then follow with waterlox or add some stain to the waterlox to make "polyshades". Always do samples before committing.Less stain is better, too much stain mixed in the WL will make it streak.Again these systems are not recommended for violins by me, but are most likely fine for instruments that that do not have such dynamic frequency parameters

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By now we all get the understanding that hardware store varnish is not good for instruments. Why?

(1) won't last (2) muffle the sound (3) does not look good. Which one or all of them?

Lumping all hardware store varnish into one catagory, (not good for instruments) probably isn't really an accurate way to catagorize them, since there is a huge variety of different finishes available.

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Lumping all hardware store varnish into one catagory, (not good for instruments) probably isn't really an accurate way to catagorize them, since there is a huge variety of different finishes available.

++++++++++++++

Hi CT,

There is only one kind of varnish in hardware stores, polyurethane based.

The people here talk about spirit or oil etc. kind of varnish.

I asked them if they have de-wax shellac, they said there never have wax in shellac only have alcohol in it.

They said shellac is good anyting but it won't last , you can (or I can) apply any other varnish on it. It will

flack(?) flick(?) ( curl up in small pieces like old paint burn, I guess) after sometime.

Those are the hardware store people's answers.

In short, it won't last or look good on an instrument. Of course, hardware people would not be concerned with acoustics.

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++++++++++++++

Hi CT,

There is only one kind of varnish in hardware stores, polyurethane based.

The people here talk about spirit or oil etc. kind of varnish.

I asked them if they have de-wax shellac, they said there never have wax in shellac only have alcohol in it.

They said shellac is good anyting but it won't last , you can (or I can) apply any other varnish on it. It will

flack(?) flick(?) ( curl up in small pieces like old paint burn, I guess) after sometime.

Those are the hardware store people's answers.

In short, it won't last or look good on an instrument. Of course, hardware people would not be concerned with acoustics.

http://www.maestronet.com/forum/index.php?...t=0&start=0

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++++++++++++++

Hi CT,

There is only one kind of varnish in hardware stores, polyurethane based.

The people here talk about spirit or oil etc. kind of varnish.

I asked them if they have de-wax shellac, they said there never have wax in shellac only have alcohol in it.

They said shellac is good anyting but it won't last , you can (or I can) apply any other varnish on it. It will

flack(?) flick(?) ( curl up in small pieces like old paint burn, I guess) after sometime.

Those are the hardware store people's answers.

In short, it won't last or look good on an instrument. Of course, hardware people would not be concerned with acoustics.

In short you are getting information from people who do not have a sophisticated level of knowledge, therefore your level of understanding will be unsophisticated

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In short you are getting information from people who do not have a sophisticated level of knowledge, therefore your level of understanding will be unsophisticated

+++++++++++++++

Wait a min.

My point was that if it is good for the funiture it would be good for an instrument except acoustic (functionality).

We hardly deal the question of acoustic here.

(PS. Dr, Nagyvary's attempt was mentioned here but later deleted)

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My point was that if it is good for the funiture it would be good for an instrument except acoustic (functionality).

We hardly deal the question of acoustic here. (except Dr. Nagyvary who used his special varnish to get the tone, another topic for another time))

Discuss Nagyvary at your own peril. If you are new member, notice that you can search old threads for topics.

If you are a new hobbiest, forget acoustics. Get the best sound in the white violin. Watch out for various methods to darken wood, it is not a trivial problem. At some point, seal with something to keep too much varnish from penetrating the wood, especially the top grain runnout. Any shellac cut down with alcohol should work for first efforts.

After that, go for looks. Nobody can help you. You have to be willing to read all of the stuff available and try various things. Do this on samples. Wood is nice, but Glass is cheap, get it free as cutoffs at your local friendly hardware store.

And forget about violin varnish. You are right in your first statement, up to a point. But it is a good thing to learn as much as you can about commercial varnishes in addition to special recipes that have been talked up in this sort of forum.

Urethane has adhesion problems. I avoid it. But I use alkyds in emulsion varnishes. CT (Craig) and I are experimenting with Ace Spar which is an older style linseed-phenolic alkyd. But we have different uses as far as I know.

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Urethane has adhesion problems. I avoid it. But I use alkyds in emulsion varnishes. CT (Craig) and I are experimenting with Ace Spar which is an older style linseed-phenolic alkyd. But we have different uses as far as I know.

Yes we do use it differently. Waaay differently.

But, the fact is that it is working well for both of us, within our chosen methods. For someone looking for a straight 'off the shelf', hardware store oil varnish (which is what I was answering specifically) Ace brand Oil-Based Spar Varnish works EXACTLY like most commercially available (from violin supply dealers) violin oil varnishes that I've used in the past, with the added advantage that I can shoot down to the Ace hardware store, and pick up a quart for well under $10.00.

Is this varnish superior or inferior to most generic violin supply house oil varnishes? Who knows? I have never read the ingredients on any of them, and they usually don't advertise what is in them as far as I know.

If you choose to research John's technique, (he posted some really nice photos of his varnish here a couple days ago) there is an amazing new area of investigation dealing with emulsions made from this same Ace brand oil varnish.

A whole new area of experimentation opens up. Not just a different application technique, but a basic variation in the chemical treatment of the medium...

So - this is in furtherance to my reply to the statement that;

"By now we all get the understanding that hardware store varnish is not good for instruments. Why?

(1) won't last (2) muffle the sound (3) does not look good. Which one or all of them?"

So, I say that this statement is not necessarily true.

In answer to - "Which one or all of them?"

None of them.

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Yes we do use it differently. Waaay differently.

But, the fact is that it is working well for both of us, within our chosen methods.

It may not develop a patina like a poly-terpene varnish, but when new I am treating it like "apothecary's varnish." It is a the bulk of a film. Period. If something works, likely the methods can be extended to a polyterpene varnish such as cooked tree sap or whatever.

If you ignore color problems (if you don't care that it is almost colorless), then it serves as a medium oil varnish.

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That Ace Spar varnish is pretty damn good. I love its looks, but cannot attest to its acoustical behavior - yet. But one should use all things in moderation nevertheless. This applies to any varnish.

Stay tuned.

Mike

In moderation as in "thin". I agree. If it is to long in the oil, try Pratt & Lambert #38 interior. It dries a little harder. I have mentioned this to you, but I say it for any other readers.

These varnishes may age or wear differently than others, but at least you can adjust their physical properties a bit by mixing in whatever proportions. If you want crazing or other patina, forget them.

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