Restoring glass after grinding and edge

[TeeStew]

Sometimes when I slump a large bottle into a divided bottle mold the edge can be sharp in a couple spots after slumping so I use my glass grinder to smooth out the spot. On a green slumped bottle this is particularly noticable. I have tried using Renaissance wax and clear nail polish to restore the gloss where I grind but I am on all that pleased with the end results. Any suggestions for how to reduce the dulled edge and return some of the luster in that spot?

[Emily Speight]

cold work.

if you use diamond hand pads and a cerium pad at the end you can get a fairly nice finish, though it may not be as shiny as you like.

you can *try* fire polishing with the piece supported in the mold, however in my experience, this results in a distorted lump of glass since the fire polishing temps are higher than slumping temps.

[Morganica]

Coldworking will take down the edges, definitely. The problem with any kind of coldworking is that once you start, you pretty much have to coldwork the rest of that area to match because otherwise it will always look different. Touchup with varnish or something similar will probably always show a bit (and if you're making glassware or vases there's a good chance that it will lift off over time, which wouldn't be a very nice surprise for your recipient). Even fire polishing can't disguise the difference sometimes.

That's why it pays to think pretty carefully about how you engineer cuts, grinds, attached areas, etc. If they're going to show, you've got to plan on doing the entire edge or plane to make things look even. As Emily says, it's not that difficult to do by hand, honestly.

In this case, I'm thinking your grinder head is probably too coarse for the work you're trying to do. More than likely it won't take more than a couple of licks with some wet-dry sandpaper or a fine diamond hand-pad to knock off a sharp slumped edge. I'd try 400- or 600- grit to start, go very carefully right on the sharp point and not past it; just wear it down slightly, and see what that does.

[Emily Speight]

In this case, I'm thinking your grinder head is probably too coarse for the work you're trying to do. More than likely it won't take more than a couple of licks with some wet-dry sandpaper or a fine diamond hand-pad to knock off a sharp slumped edge. I'd try 400- or 600- grit to start, go very carefully right on the sharp point and not past it; just wear it down slightly, and see what that does.

I agree with this. I've been hitting my sharp points with my 400 grit hand pad and it works pretty nicely. It's still noticeable but it's nicer than being scratched.