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I recently bought some turps, mastic, and, for the fun of it, amber

from Kremer. I've been working on making a shoulder rest lately,

and would like to give it a nice finish. From what I have read,

amber seems to give a nice color, and is very durable. I would like

to know if anyone has recipes/procedures for procuring this, and if

I should include a ground - or use this as the ground, if the color

is light enough.

What also might be interesting would be David Rubio's

ground.....

"In my attempt to produce a slurry containing these elements in

roughly these proportions, I mixed 45 gms of Calcium Lactate with

l0 gms. Alum, 3 gms. Manganese Sulphate, 3 gms. Titanium Dioxide, 5

gms Yellow Iron Oxide 10gms Mica Powder with ordinary tap water

(containing Chlorine) to make a thin suspension. Separately I

prepared a 50% solution of Potasium Silicate.

Using a cloth well wetted with

Pot Silicate Solution, I ragged a coat on to the bare wood. While

the Pot Sil Sol was still wet(this requires fast working) I ragged

on a liberal layer of the slurry of salts. The chemical reaction

takes place within the fibre of the wood and once dried, forms a

hard concretious layer (basically) Calcium Silicate which cannot be

rubbed away and could even be burnished with an agate to an

eggshell texture. A test I made in a jar with the mixture together

gives a Ph reading just over 7.

The appearance of the layer on

the wood is at once very alarming as the wood grain appears to be

almost totally obscured by a plaster like covering. Rosin oil

renders the layer perfectly invisible up to about l2 microns in

thickness....."

As you can see, all of this would be more for the sake of

experimentation than economy - but as I will be making my first

violin this summer (hopefully....), it wouldn't hurt to have an

understand of making varnishes and grounds.

Just for laughs, the luthier who made my primary violin had once

used beer in his varnishes, though i'm not sure if he used it on

mine.

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Bad enough that I'd rather recommend using beer as a ground. Examples I've seen never looked good, but then again, someone might have figured out how to do a nice job with it.

By the way of putting strange things into varnish, I've heard of a maker who, in a desperate search for Secret of Strad, put his son's poo into his varnish. I don't know how true that story is, but I've acutually seen his violins and they had tendecy of having slightly dull brownish finish.

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quote:


Originally posted by: Tets Kimura By the way of

putting strange things into varnish, I've heard of a maker who, in

a desperate search for Secret of Strad, put his son's poo into his

varnish. I don't know how true that story is, but I've acutually

seen his violins and they had tendecy of having slightly dull

brownish finish.

Then he moved on....

Now I belive he's using guar gum + turpentine/fruit pectin/borax +

emulsifier with a bunch of metals, et cetera.

How about amber varnish? Is it good? I've read a couple of posts

concerning it, but none gave detail in how well it works, other

than the fact that they use it themselves.

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I know someone who uses it as a ground/sealer coat, then uses a pine resin varnish on top of that. I've managed to borrow some of his Amber varnish to use as sealing coats on a Lute bowl made of Ash. I'm hoping it will fill some of the large pores in the wood before using my homemade pine resin varnish. The Amber varnish is proving very slow to dry - 4 or 5 days before it is touch dry. I'm not sure why it is so slow in drying, I do know that it does dry without taking an imprint but that takes weeks. Almost the opposite of the pine resin varnish, which in my experience is very quick to dry- and thats without added driers.

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Hi Collin,

I have recently started making my own amber varnish. I have found

the descriptions given in Geary  Baese's book on the old

italian varnishes to work for me. The difficult part is to fuse the

amber, which requires A LOT of heat. In my experience 300°C is

not enough. I use special lab equipment (glassware and electric

heat source). You also get a lot of toxic and smelly fumes (It

 can not be done inside). Once you have fused the amber, it

easily dissolves in linseed oil (at a much lower temperature) and

it gives a very thick varnish that dries within 24h in my UV

cabinet.

Good luck if you want to try it, but I suggest to be very

careful!

Fridolin

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quote:


Did your freind say anything about the hardness?

No. He just said that he uses it as a sealer coat much in the way that people use shellac before applying an oil varnish. I'm making the assumption that the Amber varnish will result in a harder film than a similar pine resin varnish but I could be wrong on that. I've yet to do the test but I have enough of his Amber varnish to smear it on my window (and my Lute) where all the other types of varnish are tested. These include Tru-oil, my friends pine resin (cooked at 160 C), my pine resin (cooked at approx. 250 C) and my D.Mastic Varnish. The Tru-oil seems soft (easily scratched) followed by DMV, followed by my pine resin, and my friends pine resin seems to be the hardest. Of course the oil contents of these are not the same so this probably accounts for some of the results.

The Amber varnish was cooked with walnut oil, except that it was exactly the same source/batch of oil that was used in making the pine resin varnish. The Amber dries very, very slowly. The pine varnish (on a sunny day) can be touch dry in a few hours. I can't explain why the Amber takes so long before it is even touch dry.

The Amber varnish also results in a glossier harder looking surface than the pine resin varnishes. So does the DMV. Here I'm only referring to the way it reflects light and not the actual hardness of the finish.

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I use amber as an additive to oil varnishes made usualy from pine and sandarac (a third or qarter part of other resins). I also melt it at 300°C (which seems enough to me, I read that it melts at 285°C but starts burniing at some 360°C). I second Fridolins post, nasty and dangerous job.

The varnish with abmber is in my experience: 1) harder, 2) dries quicker.

Matej

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Patience and plenty of fresh air for the varnish maker but not too much for the amber. Amber oils and succinic acid will boil off first. Have a loose fitting lid of some type available to prevent excessive burning. After lots of smoke you will begin to melt the amber rosin that most "amber varnish" is made from. Supposedly their is another way to get a clearer product through dry distilation but I have not tried it. Crosslinking of the polymers strengthen the amber which make boiling/running not so easy. I might have found a way to reduce crosslinking to lower BP with a pretreatment and get more product but I don't want to give bad information without more experimentation. I am sure commercial manufactures have equipment and knowledge so none of this is really "secret" just not as convenient for some folks.

Mike

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In the vernice bianca thread (that which Tets Kimura linked to),

DarylG  wrote:

quote:


I get the amber from Kremer. Carefully sort out the best

pieces, avoiding the bone colour amber. Rinse with water to clean

off dirt. Melt (fuse) the amber slowly in a pot to a temperature of

340C-370C. It smokes like all hell but eventually the smoke dies

off and it foams up a bit. Pour the molten amber into a pan to

cool. The fused amber is then crushed with a mortar and pestle.

Washed linseed oil is slowly heated in a pot to 260C. Add crushed

amber and slowly increase temperature to 300C. Hold this

temperature until a long thread can be pulled from a drop of

varnish. Cool to 150C and add turpentine. Strain thru fine paint

strainers and bottle. It can take some experimenting to get ideal

cooking times for the various stages and be able to recognize when

things are done. IMO, the most important stage is the fusing. The

other variable I've been experimenting with lately is the oil:resin

ratio. This really can change how the varnish brushes, dries,

polishes, feels, wears, and likely sounds...though I don't have

enough experience to theorize much about that. My varnish dries

overnight in the lightbox and is a lovely reddish-golden colour.

This is where I'm at now, though I'm continuingly trying to refine

my varnish/varnishing.

He adds turpentine, but no one mentioned it in this thread, but

instead said that it dissolves easily in linseed oil. As it

obviously isn't necessary, would it have a negative or positive

effect on the qualities of the varnish? He also mentions not using

bone-colored amber - any one know why it undesirable?

Thanks to all who have replied in this thread - I've learned quite

a bit.

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For most of cooked oil varnish, turpentine is added to thin the resulting varnish, and not for disolving resins, like in Michael's Mastic Varnish. I don't know whether Amber varnish without any solvent is workable or not, but many other oil varnish works pretty well with or without it.

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Thin carefully at about 150 C for a couple of reasons. This type of cooked varnish from my humble experience will quite hard if allowed to cool without thinning. At that point I don't even know if it could be thinned.

Another reason to thin while still warm is so it can pass through a filter cloth easily.

I have heard that amber colophony is an available product, if so this would make amber about as easy to make as any other cooked type of varnish. Amber oils and succinic acid are valuable products in medical and cosmetic industry. The left over resins are good for varnish. When we cook the amber these valuable substances literally go up in smoke and are wasted.

Interesting note on the succinic acid is it is a vasodialator and was used in the past for medical purposes. Some modern and very expensive migraine medicines are have succinates in them.

Mike

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The addition (very carefully) of turpentine during the varnish cook does more than just dropping the viscosity of the final varnish.

The reaction of turpentine with the oil and resin promotes a mutual solubility which cannot happen without the turpentine.

Joe

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Manfio,

I guess this qualifies as a trade secret...but not for the lack of wanting to discuss the way varnish is made. [Outside of trying to protect my income.] The addition of turpentine to the varnish is not quantifiable in the same sense that oil and resin are. The amount used and the process of addition have everything to do with the quality of the outcome. But for this to work for you on a specific varnish, using a specific resin or oil prepared in a specific way, the only way to work out the process is observation and experimentation.

My opinion.

Joe

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quote:


Originally posted by:
mcarufe

Joe,

On the subject of turpentine, has something changed with quality of turpentine? I notice that it now smells more like mineral spirits than that resinous boquette it used to have.

Mike

I've just received some 'pure gum turps' from a supplier here in the UK. No, it really does not have that same 'boquette' that I'm familiar with. Something has changed and it's probably for the worse.

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One of the issues with turpentine is that it is not used very much. The shelf life is not very long so there ends up being a lot of old turpentine out there. Don't buy anything in a can...the turps reacts with the can liner. If the turpentine smells good and evaporates quickly with out leaving any residue, then it should work for our purposes. I buy Rachem [a Canadian firm but the turps is from Indonesia] at my local TrueValue Hardware. It comes in a white plastic bottle with a green and blue lable if you are looking for it.

I don't know an average ratio for adding turpentine to amber varnish. I am not trying to be close lipped about this...really the amount is batch dependant.

Joe

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