Wednesday, October 16, 2013

Tips for Working with Gold-Filled and other filled metals


Filled metals, like gold-filled, are an inexpensive alternative to using gold in your jewelry designs. The outside layer of gold is much thicker than plating and can even survive soldering at high temperatures. But care has to be taken to avoid exposing the base metal core. These tips from my upcoming second book on soldering will help you successfully work with gold-filled metals. 


  • Keep filled metals protected during storage. Store wires and sheets separately in plastic bags to minimize scratches.
  • Rest it on soft leather to minimize work marks while filing, etc.
  • Joins must be aligned perfectly for soldering. There's too little gold to file or even for a black silicone wheel. Just a little filing can expose the base metal core, but you won't know until days later when it tarnishes.
  • Try to match the color of the joins by using 14k or 10k yellow gold solder. A yellow tinted sterling solder is also available, but it only comes in one temperature (medium).
  • Fill joins without overfilling. Use smaller pieces of solder to avoid big lumps.
  • Prevent firescale with cupronil or Firescoff flux.
  • Because of the bond between the two metals, the melting point is lower. Never use hard solder. Use medium, easy or extra-easy. A lower temperature flame, like butane, is less likely to burn it. If a small torch is used, use a medium flame and be gentle with the heat.
  • Try to fix any scratches or problems with burnishing, which will polish without abrasion. A tumbler with mixed stainless steel shot is a safe way to polish.
  • Only use the finest grits for polishing, like blue silicone wheels, and blue - light green radials.
Check out our workshop in fabricating with gold and gold-filled at SilveraJewelry.com. And follow us on Facebook for more updates and tips. 



Thursday, August 15, 2013

Troubleshooting Tips for your Butane Torch

Sometimes, as your butane torch gets older and well used, it stops working. Usually, this means that the automatic ignitor has stopped working and the torch doesn't light. Before you throw that torch away, try these tips to fix it!

You can also catch some of these tips on our free video that I made with Beaducation: Butane Torch Safety. Troubleshooting starts at 15:56.

Safety: 

Please, before you work on or use your torch - wear safety glasses! It just makes sense. And never use a torch that is misbehaving so badly that it feels unsafe.

1 • Is the gas on?

Sure, it seems obvious, but sometimes the torch won't light because the gas lever is turned down. Turn the gas dial to maximum and try lighting again. Maybe it just wasn't getting enough butane to spark!













2 • Not enough oxygen? 

Another culprit is a lack of oxygen, which along with the butane can help the torch ignite. On some butane torches, there is a silver or black sleeve on the nozzle that rotates, opening and closing a vent that allows oxygen to mix with the fuel. If it's closed, the ignitor may not be able to spark the butane into a flame. Open it all the way and try again.













3 • No spark? 

The ignitor might be broken or clogged. How can you tell? Use a manual torch lighter, also called a sparker, to try lighting the torch. Start up the torch as usual, holding the trigger down to keep the butane flowing. Place the cup of the sparker a couple of inches in front of the nozzle and slide the flint back and forth to make a spark. If the butane lights, then the torch is fine, but the ignitor isn't working. Most torches require an external tool like a sparker to light them. Don't waste this torch just because the ignitor isn't working. Use the sparker instead. In fact, sometimes the problem is temporary, and I've seen the ignitors come back to life, days, weeks or even months later.




4 • Bad Butane? 

Not all butane is created equal. Cheap butane is oily and can clog your torch, preventing it from lighting. Check the opening of the nozzle for residue. If it's dirty, try cleaning it with a cotton swab or pipe cleaner, and maybe a little rubbing alcohol. Be sure to let the alcohol evaporate away completely before trying to light the torch! If that doesn't work, you may have to empty the torch and refill it. We've seen torches function better as their fuel is gradually replaced with better quality, premium butane. To speed things up, empty the torch by turning it on and locking it, so that the butane is venting out. This is best done outside in a safe place where the torch won't be disturbed for 20 - 30 minutes. If the torch ignites while you're trying to vent it, the flame can be blown out with a strong puff of air - from your mouth. Just keep your lips away from the heat! Once the torch is empty, refill it with the good stuff. Let it rest for 5 minutes, and then try it again.

5 • Missing something? 

This is a real life problem that has happened to me with large flame butane torches. The torch won't ignite - even with a sparker. When I checked the nozzle, the brass part inside was missing. This seems to work like a choke or something similar to make the butane focused enough to spark. Without it, your torch won't work. Often, when I look around, I'll find the little guy on the floor or on the bench. Replace it in the nozzle, pressing it in firmly with your tweezers. Usually works like a charm!
















6 • Is the torch leaking? 

Have you ever noticed butane bubbling out of the nozzle or the fuel port on the bottom? This is a good sign that the torch is too full or that it's damaged. If the torch is too full, the pressure has to release somehow, so butane will bubble and spit out, usually from the fuel port. You can release the pressure by pressing on the little nipple inside the fuel port with a flat head screw driver or something similar. A jet of butane will come out. Check for butane spittle. Repeat until the dribbling stops. If it doesn't stop, your torch is probably damaged and shouldn't be used.


7 • Is your torch a spitter? 

Does the torch light but the flame goes crazy, losing it's focused blue shape and expanding into a yellow tipped blow torch? Well, first, turn it off. Something is obviously wrong. It may be temporary or the torch may be broken. A temporary problem would be an air bubble in the fuel line. This will either keep the torch from lighting or cause the flame to sputter and expand, usually ending by putting itself out. If it's an air bubble, one of two things will solve the problem: time or patience. Over time, the bubble will work its way out and the torch will work again. Maybe 20 minutes to a few hours. If you can't wait, try running the torch in a safe place where the big flame won't cause any problems. Re-ignite the flame as necessary until, after much patience, the flame settles back to normal.

If it never stops misbehaving, the problem may be a little more serious. Press the trigger down half way, enough to start the butane flowing, but not enough to ignite the sparker. Do you see a jet of liquid butane coming out of the nozzle? If so, release the trigger. Something is wrong and the torch is spitting liquid butane in a way that is messing up the flame. What to do? Try steps 4 and 6 to release pressure or change butane. If that doesn't work, the torch may be too damaged to use.




Saturday, July 27, 2013

Answers to some Common Questions about Soldering


  • Sheet, wire and paste solder? When would I use one over the other?
More than anything, I think this is based on preference, especially with sheet or wire solder. I'm not a big fan of paste solders and how they work, nor of the fumes and toxins from the flux binders when they smoke and go airborne. Paste solders may still melt into a ball, once the flux burns off, but they can end up away from the join and make a mess. Otherwise, I prefer sheet solders for gold, since you can stamp the information on the sheet for karat, color and flow point. For sterling silver solder, I prefer wire, since I can cut it into ultra small chips or flatten it if I need sheet solder for tension or similar solder joins. Sheet and wire solder allow you to control the size and placement of solder in a way that can't be matched by paste, in my opinion, which is especially essential for cleanly soldering mixed metals. 
  • Why do I need a kiln brick? Can I just use a red brick I have in my backyard or a rock?
That's a good question and I can understand the confusion. A normal household variety brick is fire proof, but it's also a huge heat sink. Instead of helping, it will take heat away from the metal and it's pretty dirty, which can foul up the whole thing. Fire brick is used to make kilns, it's takes heat and amplifies it, making it easier to solder, and it's soft, which helps with positioning pieces for soldering. They may both have brick in their name, but they're completely different. Bonus: fire bricks are very light in comparison to building bricks. 
  • When do I use Easy, Medium and Hard solder? What is the difference?
Solders come in different melting points, called flow points, from high to low, or in jargon terms from hard to medium to easy. Using different temperature solders helps you fabricate more interesting jewelry, with lots of joins, without it falling apart or putting gaps in previous solder seams. Imagine trying to solder together a box with a stone setting. You can solder the walls together with hard solder, add a top and bottom with medium solder, and then attach jump rings and the stone setting with easy solder. The first, higher temperature hard solder joins won't open or fall apart as you add the rest of the pieces of the box with medium solder. When the setting is attached with easy solder, the medium and hard solder joins don't flow, preventing distortion or open seams. As you practice soldering and your skills improve, you'll spend more time using hard solder, until you're fabricating with only hard solder. One reason to prefer hard solder and use it as much as possible is the color. Hard solder has the least amount of additive to lower its flow point, so it matches sterling silver the best, making your joins almost invisible. 

  • When do I use Penny Brite and when do I use Pickle? What are the advantages of each?
Most jewelry studios use pickle to clean metal after soldering. It's easier and requires less scrubbing. Since natural, biodegradable pickles are now available for safe use at home, they're even safer and easier to use than more acidic pickles like Sparex. If after pickling there is still some residual firescale, you can use a brass brush or scotchbrite pad with soap and water, or Pennybrite to further clean the metal. But for my work flow, Pennybrite is just too labor intensive as a stand alone method for cleaning after soldering. Also, sometimes PennyBrite just won't get into the nooks and crannies of a more complicated design. Further, in cases of hard, baked on flux, the Pennybrite may not be able to remove the glass-like flux. You would have to soak the pieces in very hot water first, so you're basically pickling anyway.
  • Do the Jump Ring ends have to meet if I am soldering them together or will the solder fill the gap?
Solder doesn't like to fill gaps, and a "filled join" is weak and will break. For precious metal solders to work properly, the join must be completely closed. 

If the join is closed something very cool happens: the join will draw the fluid solder into the seam and into the metal, making a join so strong you could stretch a ring up to 2 sizes without it breaking! Why does it do this? When you heat the metal, it expands, creating a microscopic vacuum. That vacuum draws the solder into the seam when it flows, like a capillary action. No join - no vacuum. 

So, for example, if you're soldering a jump ring, and the join is not closed, the solder will just flow onto one end or the other, but not fill or close the ring. If you close the jump ring so that the ends of the join are touching and flush, then the solder will be drawn easily into the join. How can you tell if the jump ring is closed? Hold the join up to a low light source like a fluorescent light, and look through the join. If you see a line of light at the join, it's open. If you don't see any light, it's closed and ready to solder.
  • Can I use any kind of torch for soldering?
When you know how to solder, you can use just about any flame to solder, from plumbing blow torches to cooking torches, super hot oxygen/propane little torches to blow pipes and candles - no joke, in some countries, filigree is soldered with a candle flame and blow pipe to direct the heat. 

When I first learned how to solder in college, our only torch was a natural gas flame. It had a flame that was almost big enough for casting and we had to solder anything from tiny jump rings to bracelets with that flame. When you learn the art and craft of soldering, you learn how to adjust your torch for low and high heat, what distance you should be from the flame, where the hottest part of the flame is, etc. 

Now, of course, some torches are more ideal than others for soldering, but it depends on the material and the size of the job. If you have a big piece to solder and a small flame, you probably won't be able to heat the metal enough for the solder to flow. You need the right size flame for the job. For jump rings and simple wire pieces, a normal micro butane torch is fast and efficient. For bigger pieces like heavy gauge rings, larger settings, even bracelets, a large flame butane torch will cover more surface area and be able to heat the metal enough for the solder to flow. For gold, the same rules apply, so you can use butane torches with gold, but to really take advantage of the properties of gold, a oxy/propane little torch will let you solder faster and accurately. And let's face it, if you're soldering gold, you probably want the nicest toys to work with, right? 

For a free video on how to set up to solder safely at home, visit SilveraJewelry.com.
  • How do I put the butane in the torch? 
Most butane torches will come with instructions for refueling and you should read those carefully - not just for refueling but also for how to light and safely use the torch. That said, a lot of butane torches refuel in the same way. First, your butane should be premium quality, the best you can afford. Cheap butane is greasy and can clog your torch. Make sure the nozzle on the butane canister fits the nozzle on your torch (on the bottom of the torch is a small recessed nipple that fits the nozzle for refueling). 


Interested in learning how to solder and getting some help? We have lots of classes in jewelry making, including casting, stone setting and working with gold at Silvera Jewelry School, in Berkeley, CA. Browse our calendar of classes today.


Tuesday, February 26, 2013

How to Make an Easy and Safe Torch Station

Using a torch in a studio is easy. Especially butane torches. Check out these free videos I made with Beaducation on how to use a butane torch and how to set up to work with a torch at home.

But what if you want to use a bigger torch, like an acetylene torch? Larger torches are great for annealing, soldering bigger pieces like bracelets, and for melting your scrap into ingots. With the larger, hotter flame comes more need for safety. But with around $50 worth of simple parts from a hardware store and about 30 minutes or less of effort, you can make a fire resistant torch station.


Supplies

This torch station I made for our studio at Silvera Jewelry School is made up of simple red house bricks, and 3 sheets of thin gauge sheet steel (18 gauge). How many bricks? That depends on how big of an area you want to enclose. The average brick is 8x4x2.25 inches. For my set up, I used about 12 bricks for the base, and another 16-18 bricks for the partial wall around the firing area. The sheets of steel were about 12x18".


Make a Torch Station

I made my torch station on a counter top for working with the torch while standing. I placed 2 sheets of steel on the table top, to protect the surface from the bricks. I laid out 12 bricks on top for floor of the torch station.



Next I put another sheet of steel on top of the brick base. This not only is extra protection while using the torch, but helps to keep small bits of metal from falling between bricks!




Then I started building a partial wall around the sides. The wall is higher in back and slopes down towards the front on the sides. This helps to protect everything around you from the flame as your working inside the wall of bricks. The weight of the bricks keeps them in place, but if you're working in a place that is mad for earthquakes, you could think about gluing the whole set up together with mortar. I put a large solder board or kiln shelf on top of the sheet metal. Working directly on the steel can warp it and compromise the work area. It's better to work on a solder safe board or annealing pan with pumice.



What about ventilation?

Working with a torch can create some fumes, especially from fluxes when heated. Fluxes can release chemicals, like fluorides, which can be harmful after frequent exposures. Having plenty of ventilation and circulation of air around your torch station is recommended. Installing a simple hood or even some ducting connected to a fan in a window can draw those fumes away from you. If in doubt about your ventilation, use a lightweight respirator to protect your lungs. You only have two of them!

Also, before using a tank torch, like a propane or acetylene, be sure to read, follow and understand all the instructions for safe set up and use. Secure the tank to something heavy so they don't fall down. Always play safely with fire, like setting up a safe work area.