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Opal Carving: How to use a dremel tool

In this video Justin introduces his father Jurgen who has been carving opal for over 50 years. Jurgen really is a master and is passionate about the art of opal carving. The Dremel is a handheld tool that will allow you to carve with precision. All it takes is some patience and very good eyesight.

 

  • kb

    omg, your dad is wonderful and clearly full of wisdom. His delivery comes with an (understandable) “old-school” -I know it too well to explain it- approach. The combination of the two of you, Justin and Dad, = perfect. Educational, GREAT “secret” and heartwarming.

    I love his flash of a smile at the video end… thanks!

    • Blackopaldirect

      HI KB Thank you so much for the kind words. They are appreciated regards Justin

  • alucard123

    I love these opal carving videos with dremels. I cant afford to buy a real lapidary/polishing/cutting machine right now but dremels are not much money. Good ideal about the wood shapes for the polishing grit. Please keep the informational videos coming about the tools/grit paste and secrets, there is very little out there about them.

  • Елена Федорив

    Hello 🙂

    Thank you very much for this informative video ( your dad is great 🙂 )

    Sorry I didn’t recognise what kind of drill bid’s material he uses with paste (it’s looking white – what is it?

    What # of the diamond’s paste your dad uses for final polishing?

    Does he use felt bid with oxide cerium – or diamond paste is better?
    Regards

    • Blackopaldirect

      HI Eneha My father used balsa wood. It is a type of light wood. And I believe it was 20,000 diamond grit for the final polish but cerium oxide works just as well if not better and is less expensive.

      • Елена Федорив

        Hello Justin 🙂

        Thank you very much for information. Unfortunately don’t understand what is balsa wood :((
        Is this wood close linden or to cork?
        About cerium oxide and diamond past – I hope to test both in the future.

        Did you test past like Dialux? Here in Russia we have paste GOI ( it was create in 1930th by State Optical Institute) 4 types for polishing metal, glass, stone etc. – #4 for rough and #1-2 for for final fine polishing. It’s softer then Dialux and muuuuuch cheaper :)))

        Did you try some like this? What do you think?

        Regards 🙂

        Elena

        PS Your girl Dami Im at Eurovision Song Contest – is magnificent! The final at Saturday – I guess she can win :)))

        • Blackopaldirect

          Balsa wood is a type of very light and soft wood that is good and soaks in the abrasive powders easily. Dialux is a metal polisher and does not really work on opals. But try it as it maybe something different to what I am used to. Let me know how you go with it? 🙂

          • Елена Федорив

            I see))
            I will looking forward to try our Russian analogy – paste GOI ( the chrome oxide in the base – it’s for glass ad stones , not only for metal) – will try to use it and complain with cerium oxide/ Will let you know what I will learn from this 🙂

        • Soren Cicchini

          Balsa (Ochroma pyramidale – http://www.wood-database.com/lumber-identification/hardwoods/balsa/) wood is soft like linden, but has much coarser, open grain with lots of large pores (pockets of air) that are distributed throughout the wood, not just in the rings. These pores make the wood very light (similar to bird bones), and it is commonly used for constructing model aircraft for flying, and model ships (https://en.wikipedia.org/wiki/Ochroma). The pores are also what make balsa good for polishing because they hold the polishing compound. Linden will not be very good for this because it has fine grain, so the surface is very smooth when you carve it, and most of the polishing compound will wipe off instead of being soaked up into the wood. If you know of a hobby store that sells radio-controlled model aeroplanes, they probably sell balsa wood dowels.

          • Елена Федорив

            Dear Soren 🙂
            Thank you very much for information – with your help I found the balsa wood in our air modelling’s shop.
            What do you think about cork? I know people use cork for polishing – it works well 🙂

          • Soren Cicchini

            🙂 Отлично! Без проблем, Елена! (That is my best attempt at Russian) I’m glad you have found some balsa. I would think that natural cork is also not too bad for some materials, because it is soft and can have lots of pockets that could hold the polishing compound, but there are a couple of things to consider. Cork comes from the bark of a tree, the Cork oak (Quercus suber), and single pieces of natural cork might be expensive, or it might not be so easy to find as composite/agglomerated corks made up of many smaller, more readily available pieces of cork (https://en.wikipedia.org/wiki/Cork_(material)). Most cork that I see available is made up of many smaller pieces of cork glued together. I imagine that the glue might have filled up a lot of the pores that are in the natural cork, so it might not hold the polishing compound quite as well, but it might still work okay. If it is easier/cheaper for you to get, you could experiment with it for polishing other materials, but I think it would still be safer to use balsa for polishing opal. The reason I say this is because opal is quite sensitive to heat damage, and the structure of balsa makes it retain water better, which should help prevent you overheating the object you are polishing. You will have heard Justin talk about keeping the opal wet while “cutting” (looks more like grinding to me, hahaha!) or polishing opal, and you will see that his machines all have a continuous water stream on the tool surface to keep it cool and wet. Cork material itself doesn’t absorb water, which is why it is good for wine bottle stoppers, so it will only hold water in the pockets on the surface that also hold the polishing compound. On the other hand, the pores in balsa wood are like tubes that run up and down the length of the wood, like a bundle of straws. If you soak balsa wood in water, the water will be drawn up into these tubes by capillary action (these pores are filled with water when the tree is alive), so it has a kind of small internal water reservoir that should help prevent overheating the object that you are polishing, so I think that there is less chance of damaging the opal or other heat-sensitive materials (i.e. it should be more forgiving if you make the mistake of holding the tool in one spot too long) if you polish with wet balsa wood rather than cork.

          • Елена Федорив

            Dear Soren 🙂
            Thank you very much that you share your thoughts about this ( by the way – your Russian is very good 🙂 )
            I work by Dremel and usually have water near to wash the stone and wet the instrument while working – for me it’s ok and stone is not over warming yet 🙂
            Good idea about natural unglued cork – fortunately I have several good pieces of natural cork for my orchids ( will use it and will safe the bottle of champagne 🙂 )
            I’ll try to get balsa wood – it sounds very nice for work. But can’t wait and hope to test cork today ( will go to get some polishing compound.
            Guess if don’t forget to wet cork in time – everything will be ok 🙂
            Will let you know the results of my experiment 🙂
            Regards

          • Soren Cicchini

            🙂 Спасибо, Елена! To be honest, it is really Google Translate’s Russian, changed with my very basic knowledge of the spoken language (I still find the Cyrillic alphabet quite alien). It is a very intimidating language for English speakers for a few reasons: the alphabet is one, and speaking to locals is not so easy because they are not very expressive. It is usually easy to understand what an Italian is trying to tell you, even if you don’t understand a word (you can at least tell whether they are offering you help or threatening you!), but the Russians give very little away with tone of voice or gestures. I have only spent one week in Moscow, and it was about 10 years ago, but I still have good memories. I was there for a holiday with my brother and the locals were very good to us – maybe they thought we were crazy for coming in January, but I thought the snow made everything quite beautiful, and it was a new experience for use, coming from Western Australia. I still clearly, and fondly, remember chanting “Эй! Эй! Динамо Москва!” along with the crowd at the hockey. 😀 We were spoilt by our first game of hockey. It was a home game for Dynamo Moscow against one of the other Moscow teams, and we were up in the cheap seats having fun. The hero of the night was one of Dynamo’s national olympic superstars (whose name eludes me now), who scored a buzzer-beater to send the game into overtime, and then scored again to win the match – I have never seen Russians so animated! 🙂

            Everyone else, sorry for the sidetrack, but it is not possible for me to send a direct message to Elena on Disqus.

            Yes, Elena, let us know how you go with the cork. I would still recommend using balsa on anything valuable, because it is more like a sponge, whereas the cork only has water on the surface. About the heating, remember that this is very localised to the point of contact between the tool and the workpiece, and the stone will not conduct heat very well, so you could be holding the stone in your hand and not feel it warm up, but still cause it to crack (due to differential thermal expansion – the material close to the grinder grows so rapidly due to heat that it fractures off the low temperature material surrounding it). The high speed of the tool over the workpiece causes a lot of friction heating over a very small contact area very quickly (less than 0.1 seconds – http://link.springer.com/article/10.1007%2Fs00170-013-5472-1#/page-2). Industrial studies have shown that only about 5% of the heat generated by grinding is typically removed with the chips and the coolant, so 95% of the energy normally goes into heating the tool and the workpiece (www.tara.tcd.ie/bitstream/2262/10919/1/Babic_Torrance_Murray.doc). The more energy that can be conducted into the tool, the less energy will be heating, and possibly damaging, the workpiece, so the higher water content, as well as the bundle of straws type structure of the balsa wood both allow the tool to conduct more heat away from the workpiece. The longer you grind, the more energy needs to be removed, and the real damage will happen once there is enough heat to boil the fluid film from the surface, at which point the cooling fluid becomes ineffective and the workpiece surface temperature can reach 1,000 degrees Celsius (http://www.abrasiveengineering.com/therm.htm).

          • Елена Федорив

            Dear Soren 🙂

            First about my experience with stones

            1. I didn’t like cork – it doesn’t hold abrasive well :((((
            2. For polishing I use 2 types of felt bids – one is really taft and hard – almost as wood and the second is much softer ( I soft it with pliers) – as for me, it’s work very good. But for final I prefer to use suede back of leather) + mix I will tell below

            3. I test the diamond paste and oxide cerium (CO) – CO is better, but
            I mix CO|water + diamond paste for final polishing ( we have different names for this paste – I use russian optic diamond paste 5|3). I make homogeneous mass with liquid sour cream’s density (and store it in liquid condition) and I feel that it works faster and with better result.
            This mix has funny structure, more viscous then CO|water and felt|suede hold it tighter.

            And of course I remember about heat and use water often 🙂
            Actually my training stones are small enough ( and Ethiopian’s are freeform) and I didn’t use dop stick yet ( all by fingers) :))

            Your language’s tale is very funny 🙂 Believe me in our country you can find less and muuuuuch more expressive speakers then Moscow’s. Actually I live in different parts of USSR and Russia – at the south of our country you can meet “Italian style” Russian – full of gestures and facial expressions 🙂

            But I understand that my language is not easy to study and speak – so when I see German or Englishman who lives here and speak perfect Russian almost without ascent – I respect them very much:)
            Regards 🙂

          • Soren Cicchini

            Thanks for the detailed feedback. I like the idea of using suede to hold the polishing compound.

            I do believe you about the diversity of Russians (and also the residents of other former Soviet countries) – it’s a very big place! I did notice a difference in the appearance of people from different parts of Russia, from people with Scandinavian features from the north west, to people with darker, almost Arabic features from around the Caucasus. If I’d been there longer, I’m sure I would have seen people with eastern features. The common element that I remember was that the girls were all quite beautiful. 🙂

            I have no doubt that there is also diversity in their communication styles. One place that I’ve been where it is very apparent is Croatia. Split, on the Dalmatian coast, has a Mediterranean feel to it, and the people are quite expressive, whereas the further north and inland you travel, the more Slavic and less Mediterranean people seem to behave, with those in Zagreb (only 400 km from Split) appearing to me to be much more like how I described the Russians: playing poker rather than performing an opera. 🙂 They even had such different pronunciation of the commonly used casual farewell “Bog” ((Go with) God), that it sounded like a different word! In Split, it sounded like “Boag”, rhyming with road, and in Zagreb, it sounded like “Bok”, rhyming with clock (to my ear, anyway).