Rolling Stars Vs. Pressed Stars

[tradami]

Should the comp change between the two methods?

 

For example:

 

Pyro Science Blue:
Potassium Perchlorate 66.1
Copper Oxide 13.4
Parlon 10.7
Red Gum 9.8
Dextrin 5

Total 105

[rogeryermaw]

some comps use less water (or whatever solvent) when pressed versus rolled or cut but i have not seen any that change the chemical ratios.

[tradami]

some comps use less water (or whatever solvent) when pressed versus rolled or cut but i have not seen any that change the chemical ratios.

 

Thanks! I've heard different things from different sources and I was just looking for some clarification.

[Shadowcat1969]

As Roger says, the comp itself won't change, just the amount of solvent used to bind with. In this case water.

 

Often with pressed stars a "set" amount of solvent will be used, anywhere between about 3% and 10% of total weight added, depending on the comp (different comps will use differing amounts)

 

With rolled stars you just use what ends up working for a given comp, I don't think anyone weighs the actual solvent and uses only a specific amount, just spray on what you need with each layer.

 

and with Cut stars, often again a "set" amount is used, usually more than what gets used for pressed stars, but can also be done by "feel" once one has learned how moist to make a given comp for cutting.

[Mumbles]

Essentially only glitter type effects will noticeably change in appearance when made via different methods.

[schroedinger]

Also there are comps that arent suited for rolling, as they contain to big pieces like firefly al or coarse titanium.

[tradami]

Great information. Thank you everyone.

Edited March 14, 2015 by tradami