Michael_Molnar

Please post photos of any results.

Bill, Suggesting stealing intellectual property is a bad joke. China is ripping off the West big time. I like cheap things but not at the price of hurting our inventors. In fact, China deserves a big kick in the ass for their dishonesty..

I'm in Cremona and am visiting friends. More later.

Good to know.

White spruce is ideal rosin for cooking. I don't think that the people who purify this raw material dissolve it in anything but turpentine. I would google around and find the manufacturing methods for this. If nothing is found, I would warm it with some quality turps from Diamond G and pass it through a wire mesh to collect the large pieces. Then maybe in a liquid state, the detritus would settle to the bottom or top and then can be decanted. I would keep the temperature low so as to not carbonize the twigs and needles. Again, I urge you to google around and find an answer. I found a lot of links to purifying pine sap.

I checked my notes. Shoot me. It is 290 C.

The "foaming point" reaction that Fred mentions is for making varnish, namely crosslinking the rosin and oil, and not for roasting rosin. I have experimented with this and confirmed that I see it around 290 C.

I write scripts for Spectra Plus that change settings, measure peaks, bandpasses, etc. However, I recommend Audacity for 95% on MN who would never use these features.

I would throw out the cooked rosin that has charcoal particles. Life is too short. It's a mystery to me why the addition of linseed oil permits cooking at such a high temperature. Pure rosin burns, but not varnish. Perhaps, he crosslinking helps. Maybe Fred or Joe could shed some light on this. BTW, everything I told you works for me, so give it a shot. Be careful of hot spots on the pot bottom.

You are not adding carbon to the varnish. You are oxidizing it similar to toasting bread. If you toast bread too far, you turn it into carbon and it looks, smells, and tastes terrible. Burnt varnish has black opaque clumps that destroy the varnish. Cooking pots that have hot spots on the bottom are notorious for burning. IIRC, the foaming temperature is about 290 C. Would someone check if that is right. Roasting rosin is at a much lower temperature, a little above 200 C. Again, someone should check my figures.

Rock maple.

Thanks, Ernie. I know it is important for psychological reasons to chew over ideas. I too need to do that. Nevertheless, there are lots of great earlier posts and I wonder whether posters did a search on Maestronet before asking a question that has been discussed ad nauseam. The Tad Spurgeon website is gold and cited earlier here on Maestronet. Thanks for reminding us. In this era of misinformation, one red herring that stands out is the claim that the search feature on Maesteronet is worthless. That was true, but I find the.latest version to be a powerful tool if you take the time to learn how to use it. I will be 73 in 2 days and continue looking for new tools and ideas. I like the Maestronet search feature because I took the time to learn how to use it. Please do not think that I am putting down posts from younger/newer members who are asking questions we asked years ago. All I am trying to do is help them find the gold mine on Maestronet. Nevertheless, I am upset with my colleagues who claim that the search feature is worthless.

Kevin, You want to cure the varnish and not bleach out the color. Stop when it is dry. Beyond that is courting disaster. BTW, I have had some varnish dry in 3 hrs and other in 36 hrs. There are lots of variables involved.

Thanks. This is one of my VSA entries getting ready for varnishing. It has one of my new grounds.