Urban Luthier

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Posts posted by Urban Luthier


  1. 48 minutes ago, sospiri said:

    May I enquire why you feel that way about decreased texture?

    I can only speak for myself... I just finished a viola that has extremely fine growth (many early strads are like this -- the Archinto viola for example). I used a typical solvent free oil varnish with no sanding or polishing between coats -- the resulting surface texture on the belly is very subtle. Quite different from other instruments I've made with wider grain that results in what some call a 'ripple' or 'corduroy' effect - i.e. the summer growth swells - similar to what one sees on the Messiah strad or the Guarneri above


  2. 1 hour ago, David Burgess said:

    Made in Rome, or New York?  His working style changed quite a bit after exposure to all the nice instruments in the Herrmann and Wurlitzer shops.

    I think the Sacconi instrument in Cremona is the one pictured in his book (baroque setup decorated in the style of the Hellier Strad?) see p. 190. Honestly it has been 20 years since I visited Cremona so i'm not entirely sure


  3. 11 hours ago, Michael_Molnar said:

    Cold Mastic Varnish. 

    I wasted a fortune on mastic trying that. :angry:

    Boy, mastic is expensive isn't it! I tried it once -- followed Michael Darnton's instructions exactly. The varnish turned out really well. Smelled nice also! I found it far too soft to use as a violin varnish however


  4. 19 hours ago, A432 said:

    Not so jumpy, Jacob.

    I did not contradict you in the least.

    My objection was to this:

    Because Sacconi, among other accomplishments, literally "wrote the book" on him. This is widely acknowledged as the foundation of subsequent study of classic violins.

    And I do hope you'll have that conversations with him, because it will be in heaven. :)

    There are a couple of folks part of the MN community who learned their craft directly from the first generation of professionals who mentored with Sacconi -- so they are in a far better position to comment. (you might want to do a bit of research to find out who Jacob is as well).  Don't underestimate the value of MN and those who post here. With a bit of searching you can uncover interesting detail that extends our knowledge beyond what's written in Sacconi's book. Apparently his views evolved over time like many.


  5. 3 hours ago, David Pope said:

    For those of you planning to see The Cannon you can leave your flashlights at home. I had the chance to visit Sunday and after being told to turn off my light  a discussion with the museum staff said their agreement was to not allow light of any kind. But perhaps as the week goes on they can be persuaded otherwise.

    looking forward to seeing photos from those who go! there are many cameras that can take excellent photos in low  light - my fuji x100 for example can practically see in the dark. If visitors don't have a good camera perhaps convince a friend to who has one to join you!


  6. On 5/3/2014 at 6:30 AM, JohnCockburn said:

    No disrespect to Roger intended, but I've never found this to be any problem whatsoever. I regularly cook rosin in several 8 hour sessions to accumulate enough cooking time, and never get any burning.

    I've done this as well. As long as the temperature is brought up slowly there shouldn't be any problem. The real danger is going from hot plate to cold surface -- like what Jacob S described above. 


  7. On 5/3/2014 at 6:30 AM, JohnCockburn said:

    No disrespect to Roger intended, but I've never found this to be any problem whatsoever. I regularly cook rosin in several 8 hour sessions to accumulate enough cooking time, and never get any burning.

    I've done this as well. As long as the temperature is brought up slowly there shouldn't be any problem. The real danger is going from hot plate to cold surface -- like what Jacob S described above. 


  8. Hi NT, Yes I believe you are right about Amber varnish recipe - hardly a 'secret'. I think Donald Fell's even published a translation DeMayerne!

    Personally, I would not try to cook amber varnish myself -- it requires an extremely high temperature to crack the resin. Best  left to pro varnish makers and those who really know what they are doing!

     


  9. 18 hours ago, morgana said:

    Pine resin is toxic. Turpentines are toxic and are from pine resin.

    linseed oil needs a drying agent or is viscose and poisonous too. So yes, it really is a concoction of which if ingested, would poison you and is flammable when mixed up and heated, as it reacts with oxygen and heat, so does pine resin. Naturally dangerous.

    I would not try a 1:1 either. As said, stays tacky.

    Hello morgana. As far as I'm aware, linseed oil is non toxic. Raw pine resin and colophony are indeed toxic when cooked and flammable when cooked. Again the dangers are clearly documented in Roger's bass book.

    1:1 oil to cooked resin is a standard ratio used by many professional and amateur varnish makers. it will dry properly with UV or direct sunlight. Like anything, the key is preparation of the ingredients and the cook.

    IHargrave's bass-book really does have a lot of useful information about the varnish making process. 

    The one thing that is REALLY toxic is cobalt dryer. Donald Fells (The man who makes Alchemist varnish - which is itself a variation on the Gary Bease amber recipe) told me directly that you need to wear gloves if you use a dryer and the cobalt can be absorbed through your skin and damage your liver 


  10. 1 hour ago, MikeC said:

    I'm curious about the primers.  why did he have two?  What happens if you only use one or the other alone?  Perhaps there is some chemical reaction with the two that you don't want to happen until it's put on the wood so they can't be mixed in the bottle? 

        The shelf life thing is interesting.  It was surprising when my substance lost effectiveness after only a few days.  

    Hi MikeC. See Roger's bass book Page 104-106 and Helen M's Book. This suff is mostly likely an organic primer made from horse manure and urine. A detailed historical recipe can be found in Roubo. Roger cites it in the book. Other's here have made a variation on the recipe.  


  11. 12 hours ago, duane88 said:

    There is some of the Alchemist varnish, unopened, in the box of stuff. The amount of drier that they suggest using in order to get the varnish to dry is more than I have ever used in a very small amount of varnish! With a good light box they suggest 20 drops of drier to 10 ml of varnish, or without a light box, 32 drops of drier to 10 ml of varnish. It is solvent free, liquid in the bottles, and they suggest turpentine or spike lavender oil as a thinner.

    I remain unsure of what to do with this stuff. It's pretty expensive.

    I can only share my experience I've used it two ways - both without dryer. 1) mixed in with pumice and rubbed into the wood as aground coat. 2)  in a thin coat with pad printing method described by Koening. In Both cases we are talking very think coats. Both in my case dried to touch in a UV cabinet in 24 hours.


  12. On 3/20/2019 at 5:49 PM, morgana said:

    I just wanted to know how long it takes to dry wiping it on top of an oil varnish using a uv box. And how much are you asking for it. I make my own varnish but have not tried this particular one to deepen the colouration.

    Also just looping back to your original question. The bottles appear to be Magister Primer I and II, so not varnish at all! 


  13. 5 hours ago, MikeC said:

    how can a varnish be solvent free?   Wouldn't it be about as thick as cement ?  

    As I understand it, varnish made with out turpentine solvent (like the Hargrave recipe, magister, Alchemist, Holiter) is considered solvent free. i.e. cooked linseed oil and prepared pine resin in a ~1:1 ratio. Viscous for sure but not solid! 


  14. 5 hours ago, Mike_Danielson said:

     Roger's recipe works--but you have to go to a higher temperature then he recommends--close to 300 C, and then you can get the necessary color in less than 1 hour. 

    Personally I would not recommend anyone cook resin this high unless you have accurate way of measuring and maintaining the temperature in a controlled and reliable way. 

    The colour in Roger's recipe comes from reduction of the resin during the cook (almost 80%). If you go to high too quickly, one can come out with a greenish cast to the varnish (dependant on the resin of course). 


  15. 31 minutes ago, lpr5184 said:

    It's hard to read the label. I don't think this is varnish but rather Koen's primer which I remember had a shelf life of around 6 months.

    Yep you are right E. I blew up the picture to read it -- looks like Primer I and II. Roger talks about the shelf life in the bass book page 104.

    At this point it probably useless for production. 


  16. On 4/23/2019 at 2:40 AM, morgana said:

    I will be 50 on Saturday. I work alone live with my pets. Here is a. Selfy with my violin with me. I have another violin I made and used my own ancient violin varnish which is a recipe I create.

    It's had many fine layerings.

    I hope this upload works. Taken from my crap phone.

    I use ground layerings of different mixtures and ammounts of Venice Turpentines, Natural colour on this one, glad am I that I am alive lol x

    Nice violin! I'd recommend against the Magister as well for the reasons Not Telling notes above. Someone will likely pay dearly for it just to analyze it. But to answer your question about drying -- the magister stuff should dry overnight in a UV cabinet like any other solvent free varnish. If I remember correctly, the magister varnish isn't all that dark and Koen's system relied on pigments for colouration. If you are interested, the book of Koen's work edited by Helen M is a great investment -- it contains all his writings will commentary from those who knew him well. I think it is available from the Strad shop. if you are looking for something with a bit of colour, Eugene Holtier's varnish comes has a nice rich dark orange hue. Like the Magister varnish, Holiter's stuff is also solvent free