How to make an emerger (a fly)?

In this new video, Lucie suggests you make an emerger, also called a fly, which will be used to remove the traces left by the file during the work of metal and thus prepare the parts for polishing.
Why use this kind of tool rather than a jeweler's cabron? Because its small size and rounded shape are ideal for grinding out curves, such as those on rings, bands or closed settings.

To make a fly, we will use a small tool called an emery chuck. It comes in the form of a cylindrical mandrel with a slotted shank. The technique is to wrap one or more strips of emery paper (long strips are much better and more convenient) very tightly around the mandrel. As you use it, simply tear off the used part of the sandpaper to continue working.

To help you make this homemade emerger, Lucie, offers two solutions and a third possibility:

• use the handpiece of the suspended motor in your workshop. (00:29:03)
• use the dremel because not everyone has a handpiece at home (04:54:00)
• bonus: replace the emery board with a broken drill bit or an old milling cutter you no longer use. (05:42:18)

Tip: don't forget to soften the sanding paper by breaking your paper strip on the corner of your workbench peg (or, failing that, on the edge of a table). This will make it easier to wrap around the sandpaper holder.

What diameter? Your tool should be large enough to emerge the inside of a crimp or ring, following the curve of the ring as closely as possible. As with your emery wheels, you can superimpose several strips of emery paper on the mandrel with the same grit to increase its size.
Emerging metal parts is always done with emery paper of different grits, starting with the coarsest, then using progressively finer paper. Ideally, you should make several custom flies with different grits and sizes so that you always have a functional tool at hand.

As a reminder: When you emerge, take certain precautions: protect yourself with a pair of gloves, goggles, a mask for fine dust and work in a well ventilated area.

WHICH SANDING PAPER FOR METAL?

• Between 150 and 240, it is for roughing.
• Between 240 and 600, it's for finishing.
• Between 800 and 2000, for advanced finishing.

To choose the "right" sandpaper to use, remember that the smaller the number, the coarser the grain.