Some Information on the Importance of Particle Size
For working on copper – although some books advise removing the ‘fines’, this is not helpful if you are sifting the enamel. Don’t remove them; use the enamel straight from the jar. If you remove the fines, you are left with large grains which bounce, don’t lie evenly and can even dislodge what has already been applied.
This is particularly noticeable at the edges of pieces and can result in black rims.
What’s needed is a good mixture of particle size – as the manufacturers give us. Enamel is usually sold as 80 mesh, but this doesn’t mean all the grains are that size. Some will be very much smaller and some larger.