Alcohol for shellac

[Jerry Bruette]

Local Borg has Sunnyside brand denatured alcohol and local Sherwinn Williams has Startex brand. Would either of these be good for making shellac?

TIA
Jerry

[Steve Schoene]

Both will work fine. The Startex has relatively more ethanol (65% to 75%) with most of the rest being methanol the remainder consists of relatively small amounts of ethyl acetate and heptane. The Sunnyside now contains almost equal parts of ethanol and methanol with less than a percent of MIK. Both ethanol and methanol are good solvents for alcohol. Methanol evaporates more rapidly, which most applying alcohol finding that to be a bad thing. Isopropanol is a slower evaporating alcohol that is part of a solvent like Bekhol. Neither products has large amounts of petrochemicals. Methanol is toxic (can cause blindness --i.e. the abolition era phrase "blind drunk". Fortunately ethanol is the antedote to methanol poisoning.

[Jerry Bruette]

Steve

If I can get isopropol would that be better than denatured?

[Mark Kornell]

Jerry,

No. Straight isopropanol (available over the counter at most drugstores at 99% strength) evaporates too slowly(*) and doesn't dissolve shellac flakes nearly as readily as ethanol or methanol.

What you can do, though, is substitute some (10%?) isopropanol for denatured in a batch to have control over the evaporation rate. Experiment first - you might find that either denatured blend will work just fine. If you do want to slow the evaporation down with isopropanol, be aware that it has a strong odor which may or may not be agreeable to you.

I use pure methanol to mix my shellac as I can't get DNA or even pure ethanol at a reasonable price here in Canada. I mostly spray it, and evaporation rate works nicely. Also works well when padding. But when applying with a brush it flashes too fast, so I add a bit of natural turpentine as a retarder, up to 1%.

And BTW, rubbing alcohol is 70% isopropanol. Don't use this stuff - the remaining 30% water doesn't play nice with shellac.

(*) "too slowly" might be a matter of opinion. Even the thinnest coat will run on a vertical surface, though...

[Kent A Bathurst]

OR - go to your local likker store, and get Everclear grain alcohol.

The plus benefit: You can drink what you don't use for finishing.

[James Conrad]

+1 for Everclear.

[Jerry Bruette]

OR - go to your local likker store, and get Everclear grain alcohol.

The plus benefit: You can drink what you don't use for finishing.

Considered the Everclear route but I'm pretty sure two gallons of DNA will be alot cheaper

[Kent A Bathurst]

Considered the Everclear route but I'm pretty sure two gallons of DNA will be alot cheaper

Guaranteed.

Does not, however, taste that goo with fruit juice.

[Jerry Olexa]

DA usually most cost efficient !!

[Prashun Patel]

Please don't use methanol without doing your research first. Apart from evaporating too quickly for shellac for my taste, there are serious health effects from ingestion or dermal exposure.

[Jerry Bruette]

I went with the sunnyside dna, it was cheaper than the startex.

Does it make much difference if my ratios aren't perfect when mixing, 4 oz. shellac to 30 oz. of dna?

[Mark Kornell]

No, ratios don't need to be perfect. 4 oz. shellac to 30 oz. alcohol is slightly heavier than a nominal 1-lb cut (which is a 1:8 or 4:32 ratio). That's a fairly thin cut; making it slightly heavier won't pose a problem.

[george wilson]

Around here,you have to get a permit to buy pure alcohol. They insisted upon using it in the cabinet maker's shop in Williamsburg. I saw no reason,as it all evaporates away. I would not recommend drinking pure alcohol unless you want to really get hammered. It's GOT to kill off brain cells.

They had the brain of an alcoholic on display in a jar in the firehouse here back in the 70's. The brain was really eaten away.

Yes,DO be careful with methanol. I recommend using something else entirely.

[Larry Fox]

I have used several brands of DNA available from hardware stores around here and they all appear to work well with no discernible difference. I buy my shellac flakes from Homestead exclusively and don't have any issues with them dissolving. In fact, I was spraying some on Sunday and procrastinated the mixing until about 30 minutes before I was to start spraying and a gallon of 2# cut was ready in under 25 minutes. This was using Sunnyside which is what the closest hardware store sells. The only issue I have with Sunnyside is that there is something going on with the manufacturer of the lids on the cans that make them tough to get off - very annoying.

As to mixture - I don't think the ratios really matter that much at all. I typically start with a 2# cut and depending on where I am in the finish schedule I cut it back appropriately. The way I do it is to estimate how much I need, fill the pressure pot up with about 1/2 - 2/3 of that amount and do the rest with alcohol and add a smidge more in case I accidentally put down to much somewhere along the line. For me, I typically use shellac more as a sealer / tie coat than topcoat so it gets sanded back prior to topcoating anyway. If I were doing something like a French Polish I might be a bit more picky about ratios but.

I have sprayed many gallons of shellac on many projects and never once had a finishing issue that I could attribute to a bad ratio.

[Jay Park]

Sunnyside DNA is pretty good. Something around 90% Ethyl Alcohol and very little Methanol.

I'm in Cali, DNA is all I can hope for. Can't buy the 190 proof Everclear here and the 150 proof stuff is too watered down for shellac.

Jay