Math and Mandrels
Math and Mandrels
Why ring mandrels are not the final answer in ring sizing.
When I began my career in Jewelry making back in 2009, money was tight and I had a limited budget for tools and equipment so, like many of us I made do with second hand tools and value line products from the major Jewelry supply warehouses such as Rio Grande, Otto Frei and Contentti. My ring mandrel in particular was both second hand, and a value line model made overseas. Sure it had dents and dings in the tool steel but the ring size markers were clearly defined and easy to read, and that's all you need in a ring mandrel anyway right? So tools in hand, I started making and selling rings for the market.
My ring making process at the time was the same as how many are taught: wrap the material around the mandrel at the size you want, mark where the ends cross over, saw, file, and solder. Then forge round again over the mandrel and double check the size on the line, so the middle of the ring rests on the line of the mandrel. Standard method right? And for a while everything was good and fine..until the rings started coming back to me for re-sizing...again...and again...and again...
There was clearly a problem.
So I went back to my books. Studied the charts. Scoured the Internet. What did I learn? There is a lot of inconsistency and precious little standardization in the Jewelry industry.
First, there was clearly room for improvement in my method. Wrapping stock around the mandrel creates more waste than necessary. It also introduces variables that make the cut length a bit more random than it should be. How tight do you wrap the material? How close are you to the size line on the mandrel? How accurate are your cut markers? How wide of a kerf does your saw blade take in respect to your cut markers? And so on. So first step: remove the random elements, as much as possible.
Cut length can be calculated accurately and easily with simple math and basic geometry.
A brief review of a circle:
To determine the length of material needed for a ring of a particular size and material, the formula is:
Length = (Inside Diameter of the ring + thickness of the material) * 3.14
Or if you have circumference:
Length = Circumference of the ring size + (Thickness of material * 3.14)
Material thickness can be found with a pair of accurate calipers, measured at the thickest part of the material stock. Circumference and diameter of a specific ring size should be a constant defined by the Jewelry industry, for which we turn to readily available charts. The problem though, is that not all of these charts are necessarily accurate either...
So a size 7 should have a 17.2mm diameter and circumference of 54.4mm...wait, a 17.3mm diameter. No, a 17.35mm diameter. Errr, 17.32mm...no, 55mm circumference...no 54.41mm circumference. No, a 55.6mm circumference...?
Huh? What's going on here?
Some of these charts are rounding up. Some round down. Some are calculating based on PI of 3.14. others are using more precision at 3.14159265359...or more...or less. And a couple of them, are just plain wrong. Whichever chart you decide to use for your Circumference and Diameter constants, be sure to cross reference it against other charts. If it varies more than a couple thousandths of a mm...don't use it. A variance of 0.5mm can result in a different ring size entirely. I also suggest doing some random sampling across the chart you use and doing the math to make sure the diameter and circumference values it gives you for a specific size agree with each other. Circumference = diameter * pi. Diameter = Circumference / pi. It's worth the peace of mind to do some verification. Some of these charts don't even agree with themselves.
Now I have everything necessary to find the length of material I need to cut for a specific ring size and eliminate the randomness. I cut material for a ring, size 7 out of 18 gauge stock, 3mm wide, 1mm thick and use my chart's inside diameter of 17.32mm to calculate length: (17.32+1) * 3.14 =57.52mm cut length. I take out my precision digital calipers, make sure they're zeroed out, mark my metal, saw through the line and make the ring. I forge it out on my ring mandrel and lo' and behold, it measures a size 6 ¾. Umm, what? So I get out my calipers and check that inside diameter: yup, 17.33 darn near perfect. It should be a 7...it is a 7...the math proves it...but the mandrel says 6 ¾. Guess what?
My second hand, value line ring mandrel does not size accurately. I grab my set of ring finger sizers and dig around for the size 7 and put that on the mandrel. The sizer on the mandrel shows a size 7 ¼. Now I'm cursing.
I drive down to the hobby craft store and buy one of those black plastic ring size mandrels, racing through the checkout and tearing open the packing as soon as I'm in the car. I put my size 7-by-the-math-ring on it. It's a size 8 ¼. I'm pretty sure I did not step through a portal to the Twilight Zone on my way to the hobby shop.
Over the next few months I try 4 other “professional” stainless steel ring mandrels. I get 4 different results on my size 7-by-the-math-ring. Some are close. Some are wildly off.
Ring mandrels vary wildly by maker and materials.
After a lot of searching, I found a maker advertising precision calibrated ring mandrels. I bought 4. My 7-by-the-math-ring slides on, and it measures a 7 at the bottom edge of the ring, both sides of the ring...on 3 of the mandrels. The 4th mandrel...was a lemon and machined out of round. I kept the 3, returned the 4th. You can never have enough mandrels in the workshop anyway.
At last, ring size Nirvana!
In the years after changing my process to calculate size by math and geometry and finding calibrated ring mandrels that actually agree with the math, ring re-sizing requests have become a rarity at my shop. When it does come up, it is usually due to one of these issues:
Minor Quibbles – Measuring rings on a ring mandrel
There is a great deal of debate among Jewelers on the subject of measuring a ring on a ring mandrel by the bottom edge of where the ring comes to a rest on the mandrel, or taking that measurement in the middle of the ring band. My thoughts on this, besides the fact that the math and bottom edge of the ring size agree according to my calibrated equipment - is that when making traditional, flat-stock ring bands with straight sides, only the bottom edge of the ring actually touches the mandrel and so this is the correct place to take the size reading. If I was taking a size on a ring that had a rounded inner ring band, such as a comfort fit band, then taking the reading based on the middle of the band makes sense since that is where the ring touches the mandrel and this is how I size all of my comfort-fit rings. If I was forging flat ring bands on a mandrel and taking the size reading at the middle of the ring band, the bottom edge of the ring would be stretched wider than the middle of the band and top edge. The resulting ring would be cone shaped. If you were then to flip the ring around and forge the ring again so that the size is again in the middle of the flat band, you would have a convex shaped ring with both edges flaring outwards from the middle. I cannot agree with this. A flat ring band should be sized based on the resting place of the bottom edge of the ring, checking both sides of the ring to make sure they are in agreement. Comfort fit rings with a rounded inner band should be measured in the middle of the ring. Very wide band rings should be ordered a half size up to account for the extra compression on the finger. In my mind, this is logical.
Crappy Illustration: Only the bottom edge of the ring contacts the ring mandrel. This is where sizing should take place IMO, not the middle space that does not contact the mandrel, and NEVER measured at the top edge.
Inspiration from my Garden
A lot of our jewelry making inspiration comes from the backyard garden.
Saint George in Southern Utah offers gardeners two short growing seasons per year, interrupted by a period of hot, dry late summer sun. By mid May, we're enjoying peas, greens, radishes, spring onions, leeks, turnips and are harvesting our over-winter seed crops. Tomatoes, cucumbers and summer squash will start coming on in June as well as the first apricots and cherries. Here's a look at my May garden.
Thompson Seedless and Flame grape vines growing along the wall in my southern utah garden.
Pomegranates grow well in our southern utah climate: Dixie sweet, Pom Wonderful and Angel Red
Blossom from a Japanese long onion going to seed. I save seed stock from year to year on my favorite garden edibles.
It's been a struggle for raspberry bushes here in Saint George but I think I'll finally see a crop this year.
I favor plants that are resistant to local pests. Greens such as swiss chard, mustard greens and Asian bok choy, pak choy, chrysanthemum greens and picture below - Japanese shiso, an herb in the basil family. I use the large leaves as wraps in Korean BBQ.
Garlic chives in their second year. The pretty purple flowers are also delicious!
Our favorite spring vegetable, sugar peas. Can't get enough of them!
Red Orach going to seed in the garden. This plant along with shiso is a random "weed" now in the garden. Both plants readily reseed themselves.
Fragrant English Lavender in full bloom. One of my favorite plants.
My pumpkin patch! ;)
It's going to be a bountiful apricot harvest this year. This is a Mormon/Chinese apricot tree with edible sweet kernels.
Purple and gold pansies.
Lemon snapdragons in bloom.
Thanks for visiting!
#dlcgems #southernutah #garden #saintgeorge #utah #selfsufficency
A customer recently brought me a special piece of of petrified wood that he wanted cut into 7 pendants for his 7 daughters. The wood was collected somewhere in Utah by his grandfather in the 1930's and he felt that it was time to have jewelry made from it. The wood was a rare utah star dadoxylon in stunning red and yellow jasper.
After examining the piece of rough and discussing design ideas with the customer, we settled on carefully slabbing out the wood into 7 pieces, cutting 7 cabochons in free-form shapes to preserve as much material as possible and setting in simple sterling silver bezel settings with cut-outs in the backs to show off the stone. We settled on a price for the work, took payment and gave him an estimate on when the work would be completed. That weekend, I began slabbing out the stone.
I ended up with 8 total pieces, 6 slabs, two end cuts, only one end cut suitable for a pendant sized cab. Hairline fractures ran throughout the stone, so the cabbing process would require an extra delicate touch to ensure successful cabochons. I cut the first two cabochons into the natural free-form shape of the stone and sent pictures to the customer for evaluation.
The customer came back wanting to know if we could preserve the natural edge of the slabs. Yes, it's possible I told him however we would have to change the way the stones would be mounted into jewelry as traditional bezel setting would no longer be an option. Heavy prong settings would be required instead with much more labor involved. The customer agreed and I proceeded to cab the remaining 5 pieces, retaining the natural edge. I also completed fabricating the bezel settings for the first two cabochons.
The remaining stones with natural edges required prong settings, and since each stone was unique in size and shape, the prong placements for each stone had to be carefully mapped out to ensure that the stone would be held securely. I wanted to accentuate the natural edge of each stone as well by framing it in silver and mirroring the contours of the rough edge in the silver setting. The final result is that each piece and setting is unique. Seven stars for seven daughters in seven unique settings...sounds like something out of a fairy tale.
I will miss looking at these beautiful stones, I doubt I'll ever encounter another piece of petrified wood like it.
I mentioned earlier that there 8 pieces of wood, one end cut that was too small for a pendant. So what happened to it? The customer decided he wanted a pair of cufflinks for himself, and this end cut was perfect for the job. Here they are, set in sterling silver:
Do you have a special stone that you would like to have cut, polished and set into jewelry? We would be happy to discuss your options. Find us on Facebook, Etsy and Instagram. Or contact us directly using the contact form below.
Custom Jewelry for Metal Allergies
Metal allergies are no joke for those who suffer from them. They often result in a rash and sores from prolonged exposure to a metal they are sensitive to. Two of the most common metal allergies are Nickel and Copper. Nickel is a silvery-white colored metal that is most often seen in German Silver (nickel silver) - an alloy containing nickel that is typically used in the manufacture of inexpensive costume jewelry. Fortunately nickel is easy for us to avoid. Nickel free metals include:
Here are metals that do contain nickel (and are not used in any of our jewelry):
I was surprised to learn that most surgical steel alloys contain some percentage of nickel ( from .05% to 20% depending on the alloy) according to their MSDS sheets.
Copper is another common metal that many people are sensitive to. Fortunately, copper too can be avoided in custom jewelry and there are several good options available to use instead of sterling silver. Sterling Silver contains about 7% copper, and was developed by jewelers to create a more durable and workable silver in comparison to fine silver. However fine silver will still polish and solder beautifully and can be work hardened to give strength. And while fine silver will take scratches and blemishes more readily than sterling, it is still a fine option to consider when accommodating copper metal allergies.
Recently we received a commission to make a ring for a gentleman who has a copper allergy. We tested several alloys and options with him and determined fine silver to be the best alternative to sterling for his price point and preferences. The ring features a hand cut and polished stone of our best AAA Lapis Lazuli.
One of the potentially limiting factors in working with alternative metals and alloys is the availability of metal shapes and forms from the mill. The commissioned ring design requires heavy gauge "D" wire for the ring band, but this wire form is unavailable from our supplier in a fine silver, so we have to mill it down ourselves to complete the order. Fortunately we have a very fine Durston rolling mill in our shop with the ability to mill round wire down to "D" wire without too much trouble.
Fine silver is used entirely for the fabrication of the bezel cup to hold the stone for both the bezel and back plate. Hard, medium and soft silver solders are used for the fabrication of the setting, and since they contain no copper, they do not cause a reaction with our client.
Finally the stone is set into the completed setting and then polished. The fine silver is quite soft at this stage and must be work hardened after polishing in order to give it some strength. A tumble in stainless steel shot for a few hours does the necessary job. I found that attempting to work harden the setting manually with a rawhide mallet marred the metal, so the tumbler is the best tool for the job in this case.
Our hypo-allergenic fine silver ring is ready to deliver to our client.
Forging a Fold Form Leaf Necklace
Fold forming is the process of forging, annealing and unfolding metal to yield distinctive shapes, lines, folds and texture that would otherwise be very difficult to create using traditional metalsmithing techniques. One of the more simple, and yet beautiful application of the fold form process is the forging of metal leaves. Here I demonstrate the technique using simple tools in a project requiring multiple leaf forms to create an artisan necklace.
Let's take a moment to review the tools required for basic fold forming:
Most non-ferrous metals can be fold formed, including: copper, brass, bronze, sterling silver, fine silver, and gold. My preference leans towards copper. Copper is more malleable and easier to work with than other copper alloys (brass, bronze, sterling silver) and readily takes on beautiful patinas.
Let's consider gauge for a moment as well; selecting the appropriate gauge for the desired project is critical in the final success; select too thin of a gauge for the project and you risk structural integrity problems, fold lines breaking; metal tearing and limited forging options where the metal simply becomes too thin from forging to take on the desired final shape. On the other hand, too heavy of a gauge and you won't be able to unfold your forged folds no matter how much annealing and the piece may be too heavy to comfortably wear. In general, I offer the following advice; the larger the project, select a heaver gauge and vice versa; if you are forging earrings, 24-26 gauge is generally better. Necklaces and cuffs work well with 20-22 gauge. 18 gauge and higher should only be used for very large projects using heavy tools. For this project, I am using 22 gauge copper sheet.
To begin the project, I take my copper sheet and cut 8 rectangles 2" x 1" using my aviation snips and metal shear. These rectangles get folded in half long wise as seen below. The folded edge is hammered flat. if the metal is too difficult to fold over; anneal the metal first and then fold.
Using the aviation snips, I cut one side of the folded copper pieces on a radius, imagining what half a leaf would look like. here's what I ended up with after cutting. Again, if cutting the folded metal is too difficult for your tools, anneal the metal first; it will make the cutting much easier.
Now I am ready to begin the forging process. One at a time, I anneal the copper shapes with the torch, heating the metal up until a dull red glow appears and my torch flame turns orange. You do not need to heat the metal up to a bright cherry red, you are approaching melting temperatures at that point. Once annealed, quench the metal in water or allow it to air cool before proceeding. I do not advice quenching the hot metal directly into your pickle; the splatter and vapor of sulfuric acid is dangerous.
Speaking of dangerous, let's discuss shop safety for a moment. Always wear protective eye wear when ever you are in the studio, especially when cutting and forging metal. And if you insist on quenching hot metal in your pickle solution, wear protective clothing, eye protection and a respirator. You do not want hot acid in your eyes, on your skin, or in your lungs!
Forging the annealed copper forms involves striking one side or the other with a cross peen hammer, depending on the shape you desire. If you desire a boat or pod shape when the form is unfolded, then hammer and forge along the fold side. This will cause the metal to curve inward as it is forged along that edge. The degree of the curvature depends on how much forging and annealing you perform. The metal can only be forged so much at one time before it becomes work hardened and brittle. At this point it must be annealed again before forging can continue. I desire only a gentle curvature to my boat shaped forms, so one forging is sufficient for this project. Here's the forged form:
The forged forms must be annealed one final time so they can be unfolded into their final shape. Here I am, annealing the forged form with my torch:
Annealed, the form can be unfolded by carefully prying open the leaves of the fold:
As part of this process, a beautiful forging patina is created inside of the form. This patina can be preserved so long as the remaining work to be performed on the piece only involves cold connections. Any heating of the piece will destroy the forge patina. A clear coat would need to be applied to it as well to prevent further oxidization. The rippled texture is created by crimping the metal with round nose pliers.
I will be soldering jump rings onto each of these forms to form my necklace, so the forging patina will be lost.
Here I am soldering jump rings onto either end of the fold form elements. I use hard silver solder and a third hand to hold the ring. I prefer to stick solder these on and then quench in water and then pickle in a pickle pot with a piece of iron in it. Iron in the pickle pot will cause the silver solder to become copper plated, hiding it from view. Note that doing this will make it so this pickle can only be used on copper! Do not pickle silver in this solution if you wish it to remain silver!
Here are the leave components being assembled into the completed necklace. I double the jump rings on each connection to help the components stay straight. I have also made chain mail extensions to complete the final desired length of the necklace and forged and soldered leaf clasp components.
Here's the completed assembly. The metal has been pickled and cleaned.
I have chosen a bright polish for the final finish on this piece; this is accomplished by tumbling with steel shot and burnishing compound. This method of polishing ensures that every inch of the necklace is polished and also as the benefit of work hardening all of the components. Here's the finished necklace:
I hope you enjoyed this article on fold forming and how I forge my copper jewelry. If you have any questions, please feel free to ask. To learn more about fold form techniques, I suggest purchasing the definitive book on the subject available at: http://www.brainpress.com/Foldforming.html
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#dlcgems #copper #foldform #copperjewelry #handmade #artisan #ooak #jewelry #tutorial
Autumn Leaves in Copper
It's that time of year here in Saint George, Utah where the desert nights turn cool, the days get shorter, and the leaves and foliage start to turn golden, red and brown. The changing of seasons have great effect on my jewelry making as well and my mind turns to the warm, enchanting colors of copper. Copper is such wonderful material to work; it is soft and malleable, can be annealed and soldered, forged and folded, woven and shaped in innumerable ways. And the color of copper is ever changing, like fall leaves turning to shades of orange and bronze and deep earthy brown.
Thus inspired, I sat down and began sketching a design for an autumn themed necklace.
Forging copper using the fold form technique, I fold and shape, hammer and texture and finally unfold a piece of warm copper sheet that is to become the focal point of this new work.
With the forging complete, I look to my lapidary materials and immediately descend upon a lovely piece of deep blue Lapis Lazuli; Perfect for bringing the color of the autumn sky into the work in progress. I shape a large oval cabochon of the blue material and fabricate a copper bezel cup to contain the precious gem.
My mind turns to the chain for this piece and I think of the intertwining twigs and branches of a bare autumn tree; the viking weave technique comes to mind and I set to work with heavy copper wire and weave a length of chain using the ancient technique of the Scandinavians.
I will need end caps for the chain and hook and clasp elements, so continuing the leaf theme I forge smaller leaf elements from copper using the fold form technique and solder hand forged jump rings and hook elements onto them. The end caps are leaves of course, but curled and folded into little cones as dry leaves do sometimes when they fall to the earth and are exposed to cycles of morning dew and afternoon sunshine. A copper forged leaf shaped cuff completes the set.
All elements fabricated, it is time to assemble and bring them together. The focal piece and bezel cup become one and is accented with a round wire border. A bail is forged and soldered onto the back of the leaf pendant, sized to fit the diameter of the woven chain.
The elements of the chain are assembled. The end caps are tied onto the woven cord and clasp elements are added to complete it. the pendant focal piece is added to the chain as well and the entire piece gets polished.
Desiring deeper color than what bright polished copper provides, I proceed to gently warm the copper necklace with my torch, carefully painting color onto the surface of the copper, bringing out warm tones of orange and red and purple.
The Lapis Lazuli waiting patiently to be set finally get's it's turn and is gently bezel set into the warm copper cup awaiting it, completing the pendant component of the necklace.
Nearly complete, the entire piece gets multiple coats of a protective jewelry grade finish to keep the copper from oxidizing further and protect the future owner's skin from it's oxidizing effects.
The work finished, I sit back to admire it and smile. Autumn has been wrought into a lovely artisan necklace for someone to treasure.
(This piece is sold)
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Other examples of our work using fold forming, woven chain, metals and various patina techniques:
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A Tale of Two Stones.
Custom orders are not an unusual occurrence for us at DLC Gems; orders for custom ring sizes, stone settings, etc., are business as usual. However every once in a while we get a commission for something more distinctive or involved and invariably these prove to be our favorite kind of commissions. We had two such orders recently that I would like to share with you.
The first comes from Tiffany, who brought us something special - a Tiffany Stone cabochon in colors of lavender and cream with a distinctive broken edge. I could tell immediately that the stone was precious to her and had meaning deep beyond the mere intrinsic value of the stone. Indeed, any offer or suggestion to rework the stone was politely refused; the breaking of the stone itself had meaning for her. Instead, Tiffany wanted the stone set in sterling silver; a simple setting that could be worn as a pendant.
Accepting the commission, I proceeded to set the stone in a sterling sliver setting, bezel set on three sides to secure the stone and open on the broken edge. I adjusted the proportions of the silver back on the side with the broken edge to balance out the piece. I then polished the silver where the broken edge would be so the stone could be reflected onto the silver where the missing piece would have been. A simple setting, yet designed and executed with thoughtfulness and care. Tiffany was quite pleased with the finished work and I was grateful for the opportunity to work on a beloved stone.
Here's an update from Tiffany regarding her commission:
Thank you, sincerely! When I saw what you created with my beloved stone, I cried...Happy, Grateful tears! You are amazing to work with!, you are professional, you listen to what I asked for even though every other person I talked with said that it couldn't be done. You did it! To say you are talented is an understatement. I am forever grateful for your kindness, the fact that you allowed me to ask for what I wanted and you respected my wishes to leave my stone broken. You didn't try to change my mind. The setting is more beautiful than I imagined. I wear this beautiful necklace every day. I am so grateful! I have found the only person to make my jewelry from this point forward. No reason to search the stores for what I have in mind, I will simply contact you. And I know I will be delighted every single time.
The Second story I would like to share involves a long loved piece of self collected fire agate rough from Arizona. Bonnie brought us this stone collected some 15 years ago out in the desert of eastern Arizona and asked us if we could polish and possibly set the stone for her. The stone would not work well with traditional lapidary techniques in terms of cabochon cutting, but fortunately for her fire agate carving happens to be a specialty of mine. I took the commission and set to work carving the stone.
Bonnie's fire agate
Three weeks later and approximately 15 hours of labor into bringing out the best of what the stone had to offer I completed the commission for the gem carving, carefully carving out the fire agate and polishing it to a brilliant 100,000 grit polish. The stone was now ready to set for jewelry. To learn more about my fire agate carving technique please see my Fire Agate Carving Tutorial.
The finished fire agate carving
Bonnie was very pleased with the carving work and we proceeded to discuss a possible setting for it. She has a passion for copper jewelry and decided on a copper bracelet setting for the fire agate carving. I was happy to oblige, as copper is a material I prefer to work with and we both thought the warm copper color would perfectly compliment the warm bronze and brown coloration in the stone.
This stone would require a complex bezel setting, contoured to follow the curves and flow of the carved stone. The band for the bracelet would be fabricated from heavy gauge copper, 8 mm wide, textured, oxidized and then buffed. The contoured bezel cup would be soldered to the band, the stone set, and the entire piece polished to a brilliant gloss.
Here I am polishing the bracelet:
And here is the finished piece, stone set, shined and polished and ready to deliver to the client:
To say she was happy with the finished piece I think is an understatement; but you don't have to take my word for it, here's a lovely note we received from her after delivering the completed piece:
"Got all the way home with a big smile on my face that just won't fade ....My own rock find is now on my wrist .....I am so happy to have connected with these talented artists , they have made a dream come true just for me !"
Thank you Bonnie, for the wonderful opportunity to craft this beautiful piece of jewelry for you.
- Don @ DLC Gems.
#commission #customjewelry #fireagate #tiffanystone #jewelry #dlcgems
How I carve Fire Agate #dlcgems #fireagate
Carving a fire agate allows you to work material that would otherwise be ruined by the cabbing process. Fire agate forms in bytrodial layers and rarely conform to shapes that work well for cabs. The only way to remove all of the dark chalcedony from the fire agate layers without cutting into the fire is through the carving process.
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Tools & Equipment for Carving
Start with your piece of rough fire agate. If the fire agate has a thick cap of chalcedony on it you’ll want to carefully trim and/or grind it
off as much as possible, being careful not to cut into the fire layers.
Here, I have a small piece of rough that I tumbled for a couple days in 69/90 grit to clean it up.
Using your flex shaft and coarse diamond bits, grind away the remaining chalcedony to expose the fire layers. Be sure to keep the stone and the diamond bits wet, and keep the pressure light…you’ll just wear out your equipment faster if you try to speed up the cutting by pressing too hard.
If possible leave a thin layer of chalcedony just above the fire layers and then switch to your fine grit diamond bits to remove the rest of the chalcedony, being very careful not to grind into the fire.
In the picture you can see that I’m following the contour of the fire agate layers; carefully exposing the fire but without grinding into the fire itself. The fire layers are extremely thin, so if you hit them you’re likely to grind the color to dust.
Continue carving until you have exposed as much color as possible following the contour of the fire layer.
In this picture you can see the nodules of color being exposed and the dark brown chalcedony removed. The green, yellow and orange color layers didn't go very far in this piece, however there are lots of nice nodules of bronze fire. on the left hand section, you can see a mistake I made, carving too deep and into the color nodules in my attempt to find better colors. This is a pitfall that many carvers fall into. You can see this more clearly as this piece progresses. Learning to know when to stop cutting is a valuable lesson.
When you have completed carving out the color with the diamond bits, the next step is to smooth out your carving by removing the cut marks left by the coarse diamond and preparing the stone for polishing. This step can take several hours.
I begin with 325 grit diamond paste working it over the stone with small burs I make out of the 1/8” hardwood dowels. The picture on the left shows the stone after several hours of working out the cut marks with the diamond paste. To make a bur from the dowel, cut off a 1” length, chuck it up in your hand grip and then file a point on one end using a file.
At this point you can switch over to your stiff bristle brushes and work 600 grit diamond paste over the stone until the 325 grit’s scratch marks are gone.
Use a new brush for each grit, and wash the stone and your hands between grits with soap and warm water to prevent cross contamination. If you find a stubborn spot or hard to reach area use a wooden bit
with a point shaped to work the area.
Here's the carving after polishing with 1200 grit diamond paste. Sometimes ensuring that you've covered the entire stone after each grit can be difficult, so I use a cover coat as a guide on hard stones with fire agate with no fractures. Black sharpie marker in this case is a great cover coat. When the black cover coat is gone, I know that I've covered the entire stone and can move on.
The fire agate is now polished to 3000 grit diamond. At 3000 the colors start to really show off and shine but don't stop here; your fire agate carving deserves the best polish possible.
Fire agate polished to 8000 grit.
Fire agate polished to 14,000 grit.
Fire agate polished to 50,000 grit.
Once your carving has achieved this level of polish, you have a couple of final finishing options. For instance, you could polish to 100,000 for ultimate shine. Some carvers like to put a final oxide polish using Titanium Oxide, or a very high grade Cerium Oxide, while others will use M-5, or a mix of polishing compounds.
If you decide to use a final polishing compound, a felt disk on a mandrel can be used to work the compound over the stone. Be careful not to let the stone get too hot while doing so, or else you'll risk damaging the stone and ruining the finish. Use a file to put an edge on the disk to get into the tight spaces of the carving. felt points are useful as well.
I hope you have enjoyed my fire agate carving tutorial, please leave a comment here or on Facebook and let me know your thoughts. Every fire agate carver seems to have their own techniques and equipment preferences, and I would be curious to hear about yours.
The information and pictures presented here are the intellectual property of Don Christensen and DLC GEMS LLC. Do not publish elsewhere without express written consent.
We will be selling in Ivins, UT through the summer every Saturday as part of the Saturday Market at Tuacahn. Be sure to come out and pay us a visit! Don will be performing fold forming jewelry fabrication demonstrations throughout the day creating cuffs, earrings and pendants using this unusual metal sculpting technique.
Every Saturday @ 9 am to 1 pm through August.
See you there!
Lake Havasu Art Guild Show!
Did you see us at the show last month? We had a great time meeting all of you and showing our jewelry! Big thanks to everyone who came by and supported us at the show; it really made the show worthwhile for us.
Dave had a few entries in the juried portion of the show and came home with an Artist of Merit ribbon for his Ametrine carving set in Silver with an open back. Congratulations!
DLC Gems on Facebook
Forging A Fold Form Leaf Necklace
Autumn Leaves In Copper
A Tale of Two Stones
How I carve Fire Agate
Custom Jewelry for Metal Allergies
Seven Stars for Seven Daughters