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This is a post that has just been put up on an American faceting website. Every so often the question of dopping will arrive on a forum. This information, following, was posted by Wayne Emery, a high profile facetor in the USA. In my opinion it is very good information, though it is not the way I dop, but we will leave that for later.
Let's talk dopping.
Wax, epoxy, super glue liquid and gel all work if you understand them. Sticking things together presents a problem for some, getting them apart can be problematic, too. I am not interested in re-kindling the wax vs glue debate, but I will pass on my experiences. If you find some of it helpful, you've made my day. If not, that's okay, too. With enough experience, we all gravitate to what works for us. I've been an ardent supporter of all methods over time and I know what works for me may not be the best solution for others. Here are my observations along the journey:
I do some cutting from the rough for (hopefully) re-sale, but most of the time I'm doing repair work. For that to be economically feasible, time is of the essence and good, reliable, accurate transfers are mandatory. For me, the species of stone often dictates the adhesive I'll use. If I plan to polish the stone on a resin-type lap, that can generate heat that might make wax or epoxy a poor choice. I find that minimal wax, along with a bead of super glue around the wax-dop intersection inhibits movement caused by heat. So far, anyway. Just an observation.
Usually, after cutting a flat for the table, I use Gorilla brand Super Glue gel. It seems more resistant to water (which will ruin a super glue join sometimes) in my experience, but it is NOT waterproof. I coat my glue-stone join with a fast drying nail polish to seal it and have had no problems with that.
When it's time to transfer I almost always use wax, again, unless I will be polishing on a heat-generating lap. I have any number of cone dops pre-filled with red sealing wax. I coat the pavilion of the stone with shellac I make myself from de-waxed shellac flakes you buy for a pittance on line. I fill a small polyethylene pill bottle (inert to most solvents) 3/4 or more full of the shellac flakes, top it off with DENATURED alcohol (not rubbing alcohol). It can take a day or more to dissolve completely. I coat the pavilion with a Q-Tip and it dries in a minute or so. Make sure it is DRY! This will allow you to minimally heat the wax (just soften it) and minimally heat the stone, and when you press the two together, they are STUCK. Great for heat sensitive stones!
If you DON'T coat the stone with shellac, and minimally heat stone and wax, you can use the stone to make an impression in the wax. Add a drop of super glue to the depression and you can join the two, again with minimal heat worries. But if you allow the stone to overheat during polishing, you might have a problem, again with the wax. One way to help get around this is to have your pre-filled cone dop just barely filled or slightly under-filled with wax. After pressing your stone into the wax, remove excess wax with alcohol and a Q-Tip so no wax is on the outside of the dop, then run a bead of superglue around the wax.dop join. This will securely hold the stone properly but allow easy removal in solvent (Goof Off Super Glue Remover is the king) or by heating the dop stick about 3/4 inch from the stone with a torch while applying downward pressure on the stone, all over a towel.
Now, about removing the first dop stick from the stone without disturbing the second dop...
If you have used super glue on the first join, and you're not in a hurry, you can use a small pill bottle, 3/4 filled with fine sand and topped off with your solvent of choice. Please be aware that ALL solvents are toxic and every precaution should be taken to insure that NO ONE or NO pet can disturb this setup. They are usually extremely flammable as well. I use either Goof Off or acetone, or a mix of the two. If using this, I coat the join I wish to protect with Vaseline (petroleum jelly) and push the dop into the sand so that the join I wish to break is just under the surface of the solvent. I then cover the whole thing with small glass tumbler and wait four to eight hours it takes to break the join.
I used to use paint stripper containing methylene chloride, but that has proved to be one of the most carcinogenic materials on the planet. It's manufacture is now forbidden in the US, but it is imported legally. I'd stay away from it.
Another, safer and faster way, is to wrap some toilet paper thickly around the stone and join to be protected, and, securing that end of the dop in your transfer jig, horizontally, heat the dop to be removed while applying firm downward pressure on the end of the dop. As soon as the super glue hits about 180 F it will fail. The stone will remain cool, hopefully, and you are ready to cut the crown. You can use the same method, with care, to break a wax join.
Once in a while, after I've pushed the stone into a wax filled cone dop, I will further heat the wax while it's in the transfer jig to insure a good bond between wax and stone. Sometimes, after cooling, I find the first dop has separated from the stone with that heat, destroying the super glue bond. .I've gone so far as purposely overheating the stone, so as to break the super glue join while everything is in the jig, but this usually results in some misalignment. I think the overheating causes some undesirable expansion and contraction of the brass.
I started using epoxies in the 1970's, even wrote an article in the now defunct "American Gemcutter" about it. However, I had expansion/contraction problems with epoxies, especially when allowed to cure for 24-48 hours, so I stopped using them. I think better formulations have changed that, but I don't like waiting for the extended cure periods. Epoxy joins are easily removed by heat, but it's been years since I've used them. Maybe someone else can chime in on their usefulness.
Hope some find my rantings useful.
Happy cutting!
Wayne (Emery)
Let's talk dopping.
Wax, epoxy, super glue liquid and gel all work if you understand them. Sticking things together presents a problem for some, getting them apart can be problematic, too. I am not interested in re-kindling the wax vs glue debate, but I will pass on my experiences. If you find some of it helpful, you've made my day. If not, that's okay, too. With enough experience, we all gravitate to what works for us. I've been an ardent supporter of all methods over time and I know what works for me may not be the best solution for others. Here are my observations along the journey:
I do some cutting from the rough for (hopefully) re-sale, but most of the time I'm doing repair work. For that to be economically feasible, time is of the essence and good, reliable, accurate transfers are mandatory. For me, the species of stone often dictates the adhesive I'll use. If I plan to polish the stone on a resin-type lap, that can generate heat that might make wax or epoxy a poor choice. I find that minimal wax, along with a bead of super glue around the wax-dop intersection inhibits movement caused by heat. So far, anyway. Just an observation.
Usually, after cutting a flat for the table, I use Gorilla brand Super Glue gel. It seems more resistant to water (which will ruin a super glue join sometimes) in my experience, but it is NOT waterproof. I coat my glue-stone join with a fast drying nail polish to seal it and have had no problems with that.
When it's time to transfer I almost always use wax, again, unless I will be polishing on a heat-generating lap. I have any number of cone dops pre-filled with red sealing wax. I coat the pavilion of the stone with shellac I make myself from de-waxed shellac flakes you buy for a pittance on line. I fill a small polyethylene pill bottle (inert to most solvents) 3/4 or more full of the shellac flakes, top it off with DENATURED alcohol (not rubbing alcohol). It can take a day or more to dissolve completely. I coat the pavilion with a Q-Tip and it dries in a minute or so. Make sure it is DRY! This will allow you to minimally heat the wax (just soften it) and minimally heat the stone, and when you press the two together, they are STUCK. Great for heat sensitive stones!
If you DON'T coat the stone with shellac, and minimally heat stone and wax, you can use the stone to make an impression in the wax. Add a drop of super glue to the depression and you can join the two, again with minimal heat worries. But if you allow the stone to overheat during polishing, you might have a problem, again with the wax. One way to help get around this is to have your pre-filled cone dop just barely filled or slightly under-filled with wax. After pressing your stone into the wax, remove excess wax with alcohol and a Q-Tip so no wax is on the outside of the dop, then run a bead of superglue around the wax.dop join. This will securely hold the stone properly but allow easy removal in solvent (Goof Off Super Glue Remover is the king) or by heating the dop stick about 3/4 inch from the stone with a torch while applying downward pressure on the stone, all over a towel.
Now, about removing the first dop stick from the stone without disturbing the second dop...
If you have used super glue on the first join, and you're not in a hurry, you can use a small pill bottle, 3/4 filled with fine sand and topped off with your solvent of choice. Please be aware that ALL solvents are toxic and every precaution should be taken to insure that NO ONE or NO pet can disturb this setup. They are usually extremely flammable as well. I use either Goof Off or acetone, or a mix of the two. If using this, I coat the join I wish to protect with Vaseline (petroleum jelly) and push the dop into the sand so that the join I wish to break is just under the surface of the solvent. I then cover the whole thing with small glass tumbler and wait four to eight hours it takes to break the join.
I used to use paint stripper containing methylene chloride, but that has proved to be one of the most carcinogenic materials on the planet. It's manufacture is now forbidden in the US, but it is imported legally. I'd stay away from it.
Another, safer and faster way, is to wrap some toilet paper thickly around the stone and join to be protected, and, securing that end of the dop in your transfer jig, horizontally, heat the dop to be removed while applying firm downward pressure on the end of the dop. As soon as the super glue hits about 180 F it will fail. The stone will remain cool, hopefully, and you are ready to cut the crown. You can use the same method, with care, to break a wax join.
Once in a while, after I've pushed the stone into a wax filled cone dop, I will further heat the wax while it's in the transfer jig to insure a good bond between wax and stone. Sometimes, after cooling, I find the first dop has separated from the stone with that heat, destroying the super glue bond. .I've gone so far as purposely overheating the stone, so as to break the super glue join while everything is in the jig, but this usually results in some misalignment. I think the overheating causes some undesirable expansion and contraction of the brass.
I started using epoxies in the 1970's, even wrote an article in the now defunct "American Gemcutter" about it. However, I had expansion/contraction problems with epoxies, especially when allowed to cure for 24-48 hours, so I stopped using them. I think better formulations have changed that, but I don't like waiting for the extended cure periods. Epoxy joins are easily removed by heat, but it's been years since I've used them. Maybe someone else can chime in on their usefulness.
Hope some find my rantings useful.
Happy cutting!
Wayne (Emery)
