Starbond & small gems

[Dihusky]

I am cutting a tiny Peridot for a client, a stone was lost from a ring and the jeweller asked me to cut a replacement.

I considered that superglue might be the best to hold this onto the dop, it worked well and having cut the pavilion discovered it worked almost too well, I now can't get the table bond apart. I've applied the release agent to the bond, but so far the only bond that has separated is the transfer bond, which I've now rebonded.

The stone is so small, 2.3 x 2.4mm, it doesn't even register on my scales. Small stones have never really been my interest, but a client is a client.

The glue I'm using is Starbond Gap Filler Thick with accelerator.

Any ideas how I can get this bond apart without buggering the transfer bond, so I can cut the crown?

[steve f]

I asked my mate google and he reckons baby oil or cooking oil dissolves superglue.
you could try it by applying it with the tip of a tooth pick i suppose.

[Bucket]

Have you tried heating the dop? I haven't heard of the adhesive you're using but it sounds like a type of 2 pack, maybe an epoxy. I use heat from a gas flame to heat the dop, it will usually release quite easily. Failing that my other go to is acetone, it's used in nail polish remover but can be bought from a hardware store. It doesn't work straight away, it needs to soak for a little while so I'm not sure if that will suit you. I'm very jealous, the smallest stone I can cut these days is around 3.5-4 mm, any smaller and I can't see the facets!

[MakkyBrown]

I'd soak it in water over night, superglue is not waterproof. Don't use heat, unless you know how to use a blow torch to removed a super glued dop without transferring heat as peridot is heat sensitive.
I've removed epoxy on peridot by placing in cool saucepan of water and slowly bring to the boil but I don't think heat will help much unless it is fast and rapid with a blow touch and you should probably practice that on non heat sensitive stones first.

CheerMB

[MakkyBrown]

Or sometimes little stones let go if you give the dop a slight tap on the bench. 
If you used the same glue to transfer you might have to use the blow torch, if you do. I heat the dop halfway along the shaft with a butane(camping gas) blow touch. I rest the end of the dop against the sink and apply slight pressure so it parts quick when it reached temperature. The hot dop then falls into water in the bottom of the sink.
MB

 

[Dihusky]

I'd soak it in water over night, superglue is not waterproof. Don't use heat, unless you know how to use a blow torch to removed a super glued dop without transferring heat as peridot is heat sensitive.
I've removed epoxy on peridot by placing in cool saucepan of water and slowly bring to the boil but I don't think heat will help much unless it is fast and rapid with a blow touch and you should probably practice that on non heat sensitive stones first.

CheerMB

Trying a water soak is tempting, trouble is the bond I want to break is only 0.7mm from the new bond, the water meniscus could wick up and effect the new join as well. Might try a wet cloth with a block of ice over the stone and a pencil blow torch tomorrow if the bond dissolver doesn't do it's job.

If I tap on the bench I might break both bonds, then back to square one, never be able to re-align this titch!

I may be losing some sleep tonight thinking about this one

[MakkyBrown]

You could cover your transfer to dop junction with epoxy. I often cover the superglue joint on large stones with a little epoxy to make it waterproof and not let go when i don't want it to.

[Dihusky]

Wonder if Cliff (Vintage times) will chime in on this, he uses Starbond on small stones so may have the answer.

[Dihusky]

Well, as they say... 'Time is the healer' 12 hrs coated in release agent and the bond parted this morning, undid one dop and just pulled apart leaving some sticky goo to clean off.

[Dihusky]

Finished



Yep, it's tiny, 1.5mm across the top, 3 step pavilion and 2 step crown!

[MakkyBrown]

Great you had success I've never cut a stone that small.

[Faceting Frank]

Wow 1.5mm that is small, my smallest is a 2.6mm diameter yellow sapphire found at the Willows central QLD. Biggest found there was a green-blue 6x4 emerald cut.