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I wanted to mix up a little shellac to seal the viola ribs. Just a thin seal. I saw that it is a 1 pound cut. All the recipes have it in pounds and gallons, I don't need 10ml! So I tried to convert to all weights. Seems like a REASONABLE thing to do, but you can't find that anywhere. I came up with 200/28 grams. Got it down to 30/4 because THAT was way more than I need, and I have a 30ml measure cup. The measure for alcohol I converted to ml multiplying by .8 Ahh. I should have divided by .8.

But that isn't the problem. It should have been maybe 280ml to 28 grams, but...

That seemed like too much shellac flakes, so I only put in about 3 grams. That seems like a lot of flakes. It didn't dissolve overnight. So I added another 30ml. That didn't all dissolve so I added another 40, because that was all I had left!

It all dissolved.

I put on 4 thick brush coats. Well, as thick as alcohol flows! Going around the ribs, when I got to the start, it was dry enough. 4 coats looks like a seal coat. It still feels sort of like wood.

Is there a REAL recipe for small amounts? What sort of cut is 3 grams to 100ml of alcohol? Is that all that the Isopropyl will dissolve? It worked good, and doesn't build up. The total time to put 4 coats on might have been 5 minutes




This girl decided to lay eggs where I just moved a raised bed from. 70 days or so until they hatch.

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Why be normal?

A one pound cut would be 12 grams of flakes in 100ml of alcohol.
It won't dissolve overnight on it's own. A magnetic stirrer will help it dissolve within an hour or two.

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Craig

I have it figured at about a 1/4 pound cut. Maybe the alcohol has absorbed a lot of water? Maybe it just takes longer, and needs to have the flakes crushed. The alcohol was probably a couple years old, it takes me quite a while to go through a pint of it. It starts out at 91%. Denatured makes me sick. Going by airports can give me a headache. I haven't been around one in a while.

I'm not sure what color of shellac flake it is. Rockler was the only store around at the time. They don't sell shellac flakes anymore. Maybe like a ruby? I have about 60 grams of it left.

Thanks Graig. I should have waited! At least my math is good! I like this real thin stuff. No problem with lines in color when brushing. 1/4 pound is pretty thin though.

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Why be normal?

I just fill the jar to about twice the level of the flakes. Not sure what pound cut that works out to, but it's a good general-purpose mix. When doing wipe-on finish I add more alcohol on the pad for the final self-leveling gloss coats after micromesh.

I use a digital jewellers scale and the metric ratios from this site. https://www.woodnewsonline.com/DTEW/130 ... #finishing
I find it best to mix an equivalent 2lb cut and then dilute according to purpose. If you do not own a digital scale it is well worth getting one. They are cheap and have many uses including mixing epoxy and weighing small parts.

Roy, thanks for the link. I do have a couple digital scales; a small jewellers one for stuff like this, and a larger one for weighing boards, and plates. I need to find a good container to dump the flakes in to weigh them. Maybe crush them smaller first.

The next page on the link gave one of my problems. Craig mentioned stirring, and the guy MAKES a magnetic stirrer. But also another problem is mentioned. Temperature.

It is only 62 degrees in the basement in the morning, It goes up to a scorching 64 degrees. It was warmer a few weeks ago when we had a warm spell. One day it got up to 67 when I was down there. I actually warm it up! It usually goes up a degree or so when I work down there for a few hours. It will probably be mid July or August before it reaches the mid 70's.

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Why be normal?

Not going metric but this is something I have on my shellac shelf for easy reference.

For an 8 oz liquid measure of shellac, add 1oz by weight flakes for 1# cut. 2oz for 2#, 3 for 3#, 4 for 4#.

Breaking that down for smaller amounts is pretty easy with a digital scale and a cheap set of measuring cups.

There aren't any math cops going to argue over accuracy as it really doesn't matter. If I'm am applying with a pad I'm constantly adjusting the mix on the pad with more shellac or alcohol as I go.

I've had flakes go bad and stop dissolving completely forming kind of a gummy mess. I bought some blonde and ruby dewaxed flakes at the same time and the ruby quit dissolving and the blonde is still good. The flakes were going on 10 yrs old at the time and had been kept in jars in a dry environment. I just bought new flakes for both. At the time I asked Shellac Shack about it and they confirmed that some times the flakes go bad.

Nothing much worse than finishes that act up or don't dry.

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Brian R, Wood Mechanic
N8ZED

I have only used dewaxed shellac so please take that into consideration. I use it very often and always have a 2lb cut prepared, when it`s running low I mix some more. I work in a pretty constant 68 degrees so cannot help as far as temperature is concerned. I`ve also never ground the flakes. I`m sure left long enough it will dissolve. Just prepare it a day or two in advance and shake a few times.

I keep mine in a preserve jar and mix it in that but for a small quantity you could use any smaller airtight container that is impervious to your chosen solvent. Work out the amount of shellac and alcohol needed for your required cut. Put the container on the scales and zero them and add flakes to the desired weight. Note the weight so you can zero again in case you are interrupted or the scales auto cut off and then add the required amount of alcohol by weight.
Alcohol is around 800gm per litre but I disregard that, I just call it 1ml = 1gm. The mix is really not that critical and this gets you in the ballpark.

I only use dewaxed shellac flakes I use 1 ounce of flake to 8 oz ever clear. I also use a coffee grinder and grind my flakes to a powder for better dissolving

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I'm pretty sure the flakes are de-waxed. They are probably close to 20 years old. I'm pretty sure I got them at the Rockler store, before I ever bought anything online. I like real stores. Rockler doesn't seem to sell shellac flakes anymore. Woodcraft has some, but at 2 times the price of online. I could get a quarter pound of 4 different colors for the price of 1/2 pound of 1 color.

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Why be normal?

16 cups to a gallon, 16 ounces to a pound. That makes life easy when calculating small quantities - half a cup (4oz), half an ounce. Calculating shellac mixtures is one place where converting things to metric doesn't make sense.

Ken—

Shellac flakes go bad over time. I’m pretty sure 20 years is too long! You might want to order some fresh flakes.

Don, I've heard that the flakes last forever, and that the buttons last forever but the flakes don't. Thicker? More wax? I don't know. I've never seen a controlled test.

The flakes look good. Not clumpy. Hard and brittle. Clear. Old alcohol, and cold temps probably didn't help. It was almost mixed with the 30 ml; it just had some clumps on the bottom. I probably could have stirred them in, or put the jar on the deck in the sun.

I might get more. I do have some linseed oil that was almost a full gallon? can that was in the garage when we bought the house 32 years ago. I made varnish with it, and I think I was doing an experiment to try to add madder to the oil. This is what I have left.

It is kinda red.

I would definitely still use it. My varnish will thin with turpentine, or alcohol.
Convenient. And it mikes it easy to use in emulsions. Like adding resins in alcohol to the varnish. Or maybe adding oil to shellac?

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Why be normal?

Well, I trust Vijay Veljin, who says this on his website:

https://www.shellacfinishes.com/ufaqs/w ... w%20drying.

But if what you have is working, that's great!

Well Don, that link was interesting. Slow to mix could mean slow to dry and set too. It USED to mix really fast. I was already thinking of the sampler pack. but that is a whole lotta shellac! But it isn't much more than a 1/2 pound from the Woodcraft store. Then again the 1/2 pound will only make a quart of shellac in a 2 lb cut.

You can always visit the Woodcraft store just because. Some big board may jump out at you. It happens.

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Why be normal?

You could always check Shellac Shack as well. I like their stuff - https://www.shellacshack.com

Seems to last a long time. I use their Platina for wash coats, sealing channels and rosettes, etc… It’s almost clear and easy to sand back off.


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The best way to dissolve resins like shellac is the tea bag method. Wrap the amount of resin you want to use up in a bit of cloth, and suspend it in a wide mouth jar. Add alcohol enough to reach the bottom of the tea bag, and close up the jar. The dissolved resin will be more dense than the solvent, and settle toward the bottom, pushing the clear alcohol up to the top where the bag is. The circulation takes care of mixing, and you don't end up with a lump of stuff to stir at the bottom of the jar and all the solvent at the top. If you use seedlac and T-shirt material the wax is in large enough particles to stay in the bag, so you don't have to filter it out later: just don's squeeze the bag! Toss it out with all the wax, bug parts, bark and dirt. This is quick and simple, and will work as long as gravity exists.

WellerMart on eBay will let you buy as little as 2oz of shellac at a time and sells various varieties. Prices don't seem particularly cheap, but for those of us "occasional users" it's nice to buy small quantities of different types.