shellac

[marks265]

When using shellac in a comp. it is supposed to be disolved in boiling ethanol. What should the consistancy be or better yet how much of each should be used? I want to roll stars with this material if possible but need some detailed input. All I can imagine is that they need to be pumped or cut but again I would like to roll.

As far as reference material goes I would also take suggestions on a good book about compositions for stars with good manipulation practices and not general.

 

Thanks in advance

[TheSidewinder]

Not so sure about the "boiling" bit there, marks....

 

But IIRC Passfire has (or had) some info on using Shellac as a binder/fuel. Again IIRC, it's damned sticky stuff in comps using it as a fuel, in addition to a binder, and must be cut. Pumps just clog. Could be wrong there. I have a pound of it but haven't even cracked the tape around the rim.

 

M

[marks265]

Thanks there TheSidewinder. I was on Rec pyro and thought I had also googled. I had my last brain cell in an undisclosed location because I forgot out Passfire! I'm just gonna have to do some more putzzing 'cause I also have some colophony resin to play with too. I do have the same problem as you but I will crack the seal on my jug -normal habit for me ya know!

[hst45]

For what it's worth, I use shellac wood finish straight out of the can as a binder in my bluestar comp and it works great. I started experimenting with Euters blue stars a couple of years ago and it called for shellac. Being a woodworker I had a can of "orange" shellac in the barn so I figured why not try that. Works fine. So if you're starting from shellac flakes mix in enough solvent so it gets to a consistency just slightly looser than regular white wood-glue and you're pretty close. Hope it works for you; I'm pleased with it.

[Piet]

I stumbled on the same problem, i wanted to roll them in my star roller. My solution was to convert my shellak into powder using a coffee grinder and the ball mill.

 

Some people were scepsis on ball milling the stuff but that was not really a problem, it only takes some time. I used glass balls and a ordinary hard plastic yar.

 

The link below you find photo's i made with a microscope, it is in Dutch but look for the photo's.

 

http://www.pyro-stuff.nl/forums/index.php?...topic=134&st=20

 

The schellak will be used as fuel and maltodextrine will be added for binding.

[marks265]

Yep, I got the idea now. If you had a shellac in liquid form you would try to reduce it to a solid (which is the boiling it in ethanol I gather?). I have -200 mesh shellac so the hard part is over. I rolled a few hundred grams of Euters blue stars tonight in the pyro machine. Basically in my case I just pretended it was red gum which I guess is somewhat of a replacement from what I have read (if your preference is OK with it).

hst 45---Just curious as to what form of star you formed with the liquid, cut stars maybe??? I made a 500 gram batch of Euters blue stars, I ran the Amm. Perc. through a mortise and pestle and used -200 mesh copper. For a core I used PEPPER CORNS Anyway I lite one when wet with a micro torch it burned really slow and looked really good can't wait to put it in the air!

Also what I have read is if you want to reduce material such as larger flakes of shellac freeze it first then mill it. But you're on you're own there!

 

Once again thanks for the input. I can move on to other fun stuff!

[TheSidewinder]

Err... I don't think so.

 

I think the "boiling" reference is to get it to dissolve faster?

 

If that's correct, I can't understand why you'd need to do that. It dissolves just fine, though perhaps more slowly, in a room-temperature solvent.

 

hst's method looks to be a good one.

 

This is not an area where I have any experience, though, and I'm just parroting what I read on Passfire. At least, I *hope* it was Passfire. If it wasn't, I have NO idea where I saw it.

[Mumbles]

I've never made shellac solution, but the boiling may also be to make it super saturated so that an appropriate amount of shellac would be added with a proper wetting amount of liquid.

 

Similar to if you used 2% NC lacquer to bind dragon eggs. The amount that would wet them appropriately to be cut or granulated would result in a crumbly product because of the lack of NC.

[TheSidewinder]

Hadn't thought about supersaturation. Good point.

 

But what percentage of shellac, as a component of the comp, are we talking about here, anyway?

[hst45]

`

hst 45---Just curious as to what form of star you formed with the liquid, cut stars maybe???

Good guess mark! Euters blue is an excellent blue, and I make them as cut stars. You'll need a good prime to light it. I use Veline's superprime. Just a bit of advice, too. These stars burns for a long time, so you can make a smaller star than you usually might for a given burn time.

[marks265]

Here are a couple pics of rolled Euters blue with -200 shellac spun in my roller. They turned green in a few spots. The next time I might try 100% alcohol for wetting. I used pepper corns for core so the size is sporadic because they were different species of peppers! I just wanted to test the process. I still need to put it in the air. I tried once but 2 grams of my 4 fg in the star gun barked really good and never saw the star. Figured I'd wait before I use a smaller charge!

I got a new plan-plan B so not too worried how they look now.

 

http://i247.photobucket.com/albums/gg146/marks265/eut1.jpg

 

http://i247.photobucket.com/albums/gg146/marks265/eut2.jpg

 

It took me longer to make the comp than it did to roll by a long shot.

[Mumbles]

I just had a look through some literature. The only place I know of that has instructions for making the shellac soln was Kentish.

 

It was listed as 1/2oz to 4-5oz of alcohol. This is something around 10-12% mass per volume.

[TheSidewinder]

The recipes for stars alone over on Passfire, which appear to be using the shellac as a fuel and not just a binder, all are in that 10-12% range, too. There's a surprising number of other-type formulas overall. A lot of them rather toxic as well.

 

But no mention of using the shellac in solution. No comments for most of those old formulas actually. Not sure where I saw reference to it now.

 

Say, here a nice Blue organic!

Chlorate, Paris Green, and Shellac, 70-20-10.

[jlmemt]

I plan to do a little paris green experimenting here some day.

I need to get everything squared away though first so I can do that stuff out side. Don't really need that, or chlorates, in my shop.

 

More on topic. Does shellac get old? To the point it doesn't work right?

I tried a couple of batches of stars last year with some shellac I got that was probably fairly old. They just crumbled when dry and I could not even use them.

 

Jason

[FREAKYDUTCHMEN]

marks265, kan you cut the stars in half?

I got some problems with drying, it seems like only the outside of te star will dry.

[Mumbles]

I can't imagine it would truely get old, in the sense of it losing tack. Especially over the period of a few years. I still hear about woodworkers using shellac to coat wood and such from the 60's and earlier.

 

I've only used shellac once to wet and bind compositions. I made the unfortunate choice to use acetone instead of alcohol. Bad times there. It dried up so fast it was near impossible to work with.

 

Freakydutchmen, that would be called being driven in. It is a big problem with shellac. It dries to form a film over it's surface, and traps the rest of the solvent in for a long period of time. It is especially problematic if trying to force dry or in the sun. I have to wonder a bit if that is also what happened with Jason's stars. It's reasonably easy to tell though

 

Being that I have so little experience with it as a binding agent, it is hard to really give the exact problem. The Kentish book does say that boiling the soln improves the binding properties. I have no idea how or why though. This might be a question for Mike Swisher or some of his knowledge and experience.

[marks265]

Freaky D,

 

And all,

 

I cut a few in half. This is the same batch but many days later. It is odd that wet spot spot look still stain the star but they are not wet (as far as I can tell). I was curious myself so here are some pics. I got another over all pic just for a compare again so these are recent pics. I even turned the blinders on for 1 shot! As hst45 said they do burn a long time these last about 5 seconds.

 

The 3rd from the right has a pepper corn that shrunk away from the star. The far right had no pepper corn visible.

 

http://i247.photobucket.com/albums/gg146/marks265/eut3.jpg

 

http://i247.photobucket.com/albums/gg146/marks265/eut4.jpg

 

http://i247.photobucket.com/albums/gg146/marks265/eut6.jpg

 

The pics are respective so the left star is always the left star. With the internal oxidation I would have to say that the star can breathe but there was probably enough O2 present at the time of rolling to do what it did anyway.

 

I did not prime star yet but tried another star gun shot and it blew blind again. Even at 1 gram charge of 4 fg or smaller it is still pretty forceful. Will prime and try next time.

[TheSidewinder]

From what I've seen (and from what little experience I've had) star gun charges are measured in grains, not grams.

 

If you haven't already done so, try 1/8 - 1/2 gram per charge. It may take even less. I've fired 1/2" stars successfully with considerably less than a quarter-gram, though my results aren't scientific in any way.

 

I just "hand-rolled" a few to the right size (from the comp I was making cut stars with), and dusted them with meal. With a good fit in the gun, it took surprisingly little lift. Half of a "1/8 teaspoon" or less, IIRC.

 

M

[Bonny]

marks265, kan you cut the stars in half?

I got some problems with drying, it seems like only the outside of te star will dry.

When I made some (cut) chlorate stars with shellac last year, I don't think they ever dried... A film formed over top as Mumbles said, and I dried them for several weeks. The stars were still soft when I used them up. Once lit they still burned, but too slow so they fell back to the ground burning.

[FREAKYDUTCHMEN]

This sounds very stupid, but drying in the microwave works to get shellac stars dry. It's important to put them in the microwave right after you cutted them, otherwise they wil plop open.

Use an old microwave and don't put to many stars in it. This must always be done outside. And prevent there's no metal in the microwave.

[Swede]

I bought some shellac yesterday at Home Depot to squirrel away for a rainy day. I was hoping for shellac solids (powder) but wasn't surprised when all they had was the liquid stuff in a can. The liquid is ethanol.

 

For what it's worth, the can says it is comprised by weight 20% shellac, and 80% ethanol. You can use it as is if you don't mind the ethanol, or you can weigh some out, then heat gently (flameless) or simply let the ethanol evaporate to concentrate the shellac. Continued weighing will let you calculate how much is ethanol, and how much is shellac solids.

 

It might be useable as a red gum replacement in a few comps. Worth a try.

[Frozentech]

I would go with the method of evaporating it down slowly. Most times when Shellac is used, it is a primary fuel in the composition, not just a binder. So, you will have to add a LOT of liquid to your comp, making it a soup, to get enough shellac to fuel it. I mean, to make 100 grams of a comp that is 20% shellac, would need 100 ml roughly of this liquid shellac otherwise ? About 10 times wetter than you want it. Maybe you could use the Japanese "toro" method though.