help...repairing chipped glass crystal?

[funkyguy]

hi guys n girls..
please forgive me if this subject has been covered?
i have a nice led..with a glass? crystal(not plastic)
its rectangle and a has a nasty chip missing from one corner.
any ideas on repairing to a fair cosmetic standard?

peace to all.

geoff

[azimuth_pl]

let pictures do the talking and then we can continue

[retroleds]

its rectangle and a has a nasty chip missing from one corner.
any ideas on repairing to a fair cosmetic standard?
geoff

Sometimes flipping over is the best repair...stabilizing the area with a little clear epoxy, of course. But a nasty chip can be a full fledged crack waiting until the glass is released from the glue and the case to rear it's ugly head. From the business standpoint I never cover a person's glass against breakage if it needs to be removed for case work..... all you can do is your best and try to be careful. I do cover the crystal of all incoming watches immediatly with stick on crystal protectors so I don't have to worry about any clumsy mistakes on my part.
Stuff happens. It was a serious problem that demanded a policy.

[funkyguy]

thanks for info..very helpful..
peace to all

[bucko170]

As anyone ever attempted to add dye to resin to fill in chips in glass crystals?

I was thinking how easy it is to repair car windscreen chips nowadays, although for LED crystals I imagine color matching is probably going to be an issue.

Something similar must be done for stained glass repair in old churches etc?

[Old Tom]

I have "resurfaced" many LCD crystals using windscreen repair resin- these are anaerobic UV setting cyanoacrylates (in English, they set in sunlight as long as air is excluded!) and have rules to follow when used on watch crystals. Being CA glues you can almost certainly tint with dye or pigment them.

To resurface a crystal I do the following;-

1. Clean the surface of the crystal thoroughly- wash with soapy water, clean water, isopropyl alcohol- to remove all visible contaminants. Dry thoroughly.

2, Prepare a "face plate" to exclude air- I use a sheet of thin glass with a layer of clear polypropylene packing on to prevent the CA sticking to this plate.

3. Place the watch face up and level on a suitable surface. Run a line of windscreen resin along a long edge of the crystal under repair.

4. Lower the face plate onto crystal by first touching the plate into the glue and then gently allowing it to settle across the crystal from this edge to the opposite edge- you are trying to ensure complete wetting of the surface and exclusion of air bubbles.

5. Expose to sunlight for about 2 hours.

6. Remove the face plate- I find a gentle twist normally gets it off without too much hassle- try to avoid pulling it off vertically, you might strip the resin off. It is still quite soft.

7. Now wait at least THREE weeks. CA glues usually only 90% polymerise on first set and then gradually harden over a period of weeks.

8. Finally polish back using your favorite plastic polishing method.

This can give excellent results and save a watch for which no replacement crystals are available- especially ones that are printed on the back.

[bucko170]

Thank you for the excellent detailed reply The difficulty is going to be finding the correct dye and matching the colour up.