17 December 2017

The Importance of Keeping a Firing Log

In 1905 Spanish philosopher George Santayana wrote these well-known words “Those who cannot remember the past are condemned to repeat it.” And, for anyone that uses a kiln on a regular basis that quote can have significant meaning.

That is why we recommend that EVERYONE keep a firing or project log. We cannot stress this enough as it is the easiest ways to learn about your kiln and recall exactly what glass, metals, materials, molds, and most importantly, firing schedule you used. Over time, a properly kept log is critical to keeping track of what you’ve done. It will help you learn the particulars of your kiln plus it will go a long way towards avoiding future mistakes.

In many ways, a firing or project log is the most underappreciated tool in your studio. All too often, the enthusiasm to fire overcomes the need to keep records of the firing, resulting in unusable comments. This is an enormous mistake. The firing or project log is one of the most essential tools you have. The combination of your kiln, the materials you select, and the designs you create are exclusive to you. No one else can precisely duplicate the conditions in your kiln, so it’s up to you to keep records that are detailed enough to allow you to repeat good firings and avoid repeating bad ones.


Some people suggest that a printed log like the Bullseye Kiln-Glass Project Notes, the Paragon Ramp-Hold Firing Record or the Joy of Fusing Project Log, while others favor a simple notebook. Digital logs are also a popular option.

It really doesn't matter which log you chose as long as you document, document, document!  Some firings will require minimal notes while others might demand several paragraphs, pictures and/or sketches. Most importantly, keep you log in your work area. Use it religiously and enter essential information about each firing.

As you become more knowledgeable, you may find that many of your firings are similar and require minimal entries. But regardless of your experience level, don't stop logging your firings, as your log is a priceless tool!

10 December 2017

The holidays are coming — break out the punch! (The paper punch, that is)

Bullseye Glass Quick Tip:

In this Quick Tip, you will learn how to combine punched silver foil design elements with Tomato Red Opalescent for something truly festive just in time for the holidays!

Silver, in the form of thin sheets, can be fired with glass in the kiln to produce a palette of effects, ranging from subtle to dramatic. We just love the variety of effects you can get!

Keep in mind, when working with foil that sometimes it can be a real pain as it's super thin and likes to stick to everything. So, before punching out shapes or cutting them with scissors, take the extra time to sandwich the silver foil between sheets of paper. This creates a toothy structure that cuts cleanly and keeps the foil from tearing. 

Bullseye Kiln-glass Education Online also has a great video lesson if you want to learn more about Using Foils with Kiln-Glass.

Enjoy the punch!

03 December 2017

Increasing the Life of your Firebrick Kiln

Throughout the years, we have seen 10+ year old kilns with firebricks that are still in pristine condition and relatively new kilns that looked like they had been dropped from a three-story roof. It's pretty easy to tell when a kiln has been cared for and given that extra level of TLC or, what we like to call "KLC"... Kiln Loving Care! 

Here are a few tips from Arnold Howard at Paragon Industries on how to give your firebrick kiln that extra Kiln Loving Care:

1. Vaccuuming is a must. Vacuum the kiln interior regularly using the soft brush nozzle of a vacuum cleaner. Be sure to vacuum the element grooves, the inner surface of the kiln lid or roof, and the underside of kiln shelves and be gentle when you touch the firebricks with the nozzle. Vacuuming the grooves is essential if you have had anything explode inside the kiln. Pieces of greenware that lodge inside the grooves can burn out an element. Vacuum the kiln often if you use silica sand on the shelves. The sand, which is used to support ware during firing, can ruin the elements if it filters down into an element groove. As you vacuum the kiln, examine the walls for glass or glaze particles that have embedded into the firebricks. Dig these out carefully. Otherwise the particles will embed deeper into the firebrick during the next firing.

2. Kiln Wash is your friend. Apply kiln wash, liquid kiln coating or glass separator to the kiln’s firebrick bottom. But keep kiln wash away from the walls and elements.

3. Dry your greenware. If possible, do not fire moist greenware. It should be bone-dry and warm to the touch. If you must fire moist greenware, wait until all signs of vapor have disappeared before heating past 200 degrees F. The moisture at higher temperatures is not good for the firebricks and can cause the greenware to explode.

4. Be gentle. Lower the kiln lid (or close the kiln door) gently. Slamming the lid can crack the lid the first time it happens. Fully disengage the lid support before lowering the lid. Forcing the lid downward can break the bricks near the lid hinge. From time to time, check the condition of the lid support.

5. Keep closed. Keep the lid closed when you are not using the kiln. This keeps dust out and prevents the lid from dropping while you are away from the kiln. Do not store anything inside the kiln.

6. Level it. The kiln stand should be level and rock-steady. An unleveled stand can stress the firebricks. A stand that rocks can cause the kiln to move when jarred, knocking over ware against the sidewalls inside the kiln.

7. Don't lean on me. Do not lean too heavily against the firebrick walls while loading and unloading. Some people use a small stepladder to reach into a deep kiln. You can also cut a piece of plywood to fit across the wall that helps protect the wall during loading.

8. Try not to touch. During loading and unloading, do not touch the sidewalls of the kiln with anything. Do not allow a shelf to bump into the firebricks. The extra time and care you spend loading and unloading may add years of life to your kiln. 

9. Always look for drips. If glaze, glass, or other materials drip onto a kiln wall or the kiln bottom, repair before the next firing. Otherwise these materials will remelt and embed deeper into the firebricks. Remove the contaminant by scraping gently with a putty knife. If you remove kiln wash from the kiln bottom, apply a fresh coat to the bare spot. 

10. Don't worry! Do not be concerned about small cracks that appear in the firebricks. The cracks are normal and act as expansion joints. During firing, they close tightly.

Finally, if a firebrick edge breaks off, don’t stress. The damage is usually slight and does not affect the firings, and can easily be repaired with our Firebrick Kiln Repair Kit.

26 November 2017

Not Your Average Tile Saw

We are happy to say that the wait is over!  For years, we used a tile saw in our studio that we purchased at a local hardware store. It worked but, it frequently chipped our glass as the speed was just too fast. And, until now, we hadn't found anything that we loved so much we wanted to share it.

Introducing... the Covington MK Tile Saw!

The Covington MK Tile Saw is simply genius! Covington has taken all the great features of the MK-101 Series except they have modified the RPM's of the tile saw and slowed it down from 3450 RPM's to 2500 RPM so the glass does not get "hammered". So, whether you are cutting borosilicate, soft glass, pattern bars, or even bottles the Covington MK saw can do it!

Covington also includes a Ultimate Glass Blade with each saw to provide you with everything you need to get nice clean, virtually chip free cuts.

18 November 2017

Kiln Repair Directory

We all know, life happens... and, usually it's timing stinks!  You know how to fix the minor issues with your kiln but, sometimes after troubleshooting, you still need additional help.

Not to worry... Kiln Frog's "Kiln Repair Directory" is a great resource of over one hundred kiln repair technicians across the US.

Please be advised that Kiln Frog does not recommend or endorse any of the named repair services and cannot be held responsible for any of the work performed. As kiln technicians are independent business people, it is also possible that their advice may not always reflect our opinion.

Finally, to ensure that our list is as complete as possible, we are requesting your help! If you are aware of a good repair person or company, please let us know and we are happy to add them to our list.

11 November 2017

Math + Design

Bullseye Glass Quick Tip:

This Quick Tip shows you how to combine the power of mathematics and the beauty of metallics to create an awesome design!

The Fibonacci sequence is a numbering system found in nature, from flower petals to seashells. It’s pleasing to the eye (even if you’re not aware of it) and a versatile design tool. The sequence starts with a one, followed by a one. Each subsequent number is equal to the sum of the preceding two numbers: F (1) = 1, 1, 2, 3, 5, 8, 13, 21...

For this project, Bullseye translated the beginning of this Fibonacci sequence into centimeters and arranged them to transition from one color to another. Pretty cool, right!

Fibonacci example

08 November 2017

Evenheat Knife Ovens are READY 2 SHIP!

Need quick delivery... NO PROBLEM!

We now have a small amount of Evenheat KF 18 and KF 22.5 Knife Ovens in stock and READY 2 SHIP! 

Best of all, they all come equipped with Quiet Drive Solid State Relays and your choice of the RM3 or TAP controller!

What are you waiting for? ORDER NOW

04 November 2017

Learning to Read your Relay

No matter what kind of kiln or oven you use, unless you have mercury or solid state relays, it's a fact of life that relays need to be changed. But, before you replace the mechanical relay of a digital kiln, it is very important that you read the label printed on the side to be sure you are installing the correct one.

The label is confusing until you spend a little time studying it. On the label, find the voltage of the relay coil, which is the electromagnet inside the relay. When the electromagnet receives a signal from the controller, terminals inside the relay come together. The terminals make a clicking noise and turn on the heating elements.

The voltage of the coil is printed on the relay near a symbol of the coil. In the sample relays shown, the coil is symbolized by a rectangle with a diagonal line. The coil in the top left relay is 12 volts DC, which is the most commonly used kiln relay. The coil in the bottom left relay is 240 volts AC. The coil in the relay on the right is 200 - 240 volts AC (for 208 volt kilns).

The 12 volt DC coil is used in relays that are turned on by a digital controller. The 240 volt AC coil is used for relays that are activated by an infinite control switch instead of a digital controller. DC means direct current, which comes from the controller to the relays. The symbol for DC is a horizontal solid line over a broken line. AC is the current from the wall outlet and is symbolized by a wavy line.

The relay is rated for a level of current. The current rating of the relay does not mean it requires that much current to operate but, is the maximum safe level that the relay can handle.

28 October 2017

The PERFECT kiln for bottle slumping

Glass bottle slumping is extremely popular because you don't need to buy expensive glass and it gives artists the opportunity to recycle wine and/or beer bottles.

When thinking about buying a kiln for glass bottle slumping, it’s important to consider the size of the bottles and molds you are planning to use, before you buy it. Unfortunately, it’s not that easy as the long shape of glass bottles and molds make them hard to fit into many of the standard smaller, household current kilns.

It’s like the Goldilocks syndrome… this one is too small, this one is too big but, this one is just right. So, with that mind, Paragon Industries accepted the challenge to create the perfect bottle slumping kiln.  They recognized that most people who want to slump bottles want a kiln big enough to efficiently slump multiple wine and/or beer bottles at the same time. And, most don't have a 240v electrical circuit available, so they need the kiln to run on regular 120v household current.

With those specifications as their guidelines… the rectangular Paragon S1310 Trio was born!  And, is the only kiln specifically created for glass bottle slumping!

Now that you have the perfect kiln, here are some tips to help you make your glass bottle slumping experience more successful:

Remove labels. From washing soda to ammonia, there are many options when it comes to removing labels from bottles. Most involve hot water and soaking from a couple hours to overnight.  After the label has been removed, remember to wash the bottles thoroughly under cold water to remove any residue. Many people also use isopropyl alcohol to clean fingerprints as cleaning the glass is critical to your success!

Keep a log. Bottles come in diverse shapes, sizes and glass properties. Thicker bottles will take longer to heat and slump. Different shaped bottles will slump differently and at different rates. Different glass may have different melting temperatures. We suggest keeping a log of your firing. You may see some patterns that will help you get more consistent results.

Sample Bottle Slumping Firing Schedule
Be prepared to adjust. It's uncommon that a generic firing schedule will get you the perfect results without some modification. And, there are a million factors that can impact the temperature… maybe you loaded your kiln with more bottles, so it will take longer to heat.  Or, like your oven, some kilns just run hot, while others run cold. Whatever the cause, you will need to adjust some parts of the firing schedule to get the best results from your kiln.

Fusing bottles together. Glass compatibility, also referred to the coefficient of expansion or COE, is important to understand if you are going to be successful with glass bottle slumping. If you don’t use glass that has the same compatibility or COE, the stress will cause it to crack or break. Sometimes it happens immediately or sometimes is happens later... but, I can 100% guarantee that it will happen. Most bottles tend to be in the 82-86 COE range which is similar to float or window glass. However, since the COE of any given bottle glass is unknown, it is not recommended to fuse them with other bottles or fusible glass.

22 October 2017

Stimulate your Creativity!

Choosing color is one of the most exciting–and sometimes daunting–challenges to anyone working in glass. Maybe you are growing tired of your usual color palette and you are looking for inspiration? Or, maybe it's just time to try something new! No need to worry... thanks to our friends Bullseye Glasswe've got you covered.

Color Cues are a series of ideas on eye-catching color combinations that include recommendations on how to incorporate overlays, and how to make sample tiles. There are four exciting Color Cues which include:

Ready to get started... we've got you covered here too!  Let's go!

15 October 2017

How to Level Your Kiln with a Smartphone

I'm always reading about new things you can do with your iPhone but, this one is really cool! Did you know that your iPhone has a level hidden in the compass application? So, if you can't find your level... just break out your iPhone and you are all set to go!

  1. Remove the phone case for better accuracy.
  2. Touch the Compass icon. 
  3. Tilt the phone at different angles to calibrate the level. When this is finished, a compass will appear.
  4. Slide your finger from right to left and magically the spirit level will appear.
  5. Place the phone on a kiln shelf, and adjust the shelf until the two circles overlap. 
  6. A green screen will appear, indicating that the shelf is level.
Other brands of smartphones can also level a kiln and the directions would be similar. Before you trust the accuracy of any smartphone, please test it with a good spirit level.

08 October 2017

The Confusion about 120v Outlets

About once a week, someone tells us, “The 120 volt plug on my new kiln doesn’t match my wall outlet.” Many people do not know the difference between 15 amp and 20 amp, 120 volt wall outlets, because they look almost the same. But a 20 amp, 120 volt kiln cannot be plugged into a 15 amp, 120 volt wall outlet.

Image result for 120v 15 vs. 20amo
The common 15 amp, 120 volt household outlet (also called a receptacle) is used throughout North America. Lamps, vacuum cleaners, refrigerators, etc. plug into it. The outlet has two vertical slots; the U-shaped hole is for the green safety grounding wire.

The 20 amp, 120 volt outlet looks like the 15 amp outlet, except one of the vertical slots is shaped like a sideways T. 

NEMA, the National Electrical Manufacturers Association, has standardized these designs and designated them NEMA 5-15R and 5-20R. (The number after the hyphen indicates amperage.) Standardized plugs and outlets are so ubiquitous that we rarely think about them. But they helped to bring electricity into millions of homes and factories.

01 October 2017

Why do circuit breakers trip?

The circuit breaker is a switch that shuts off the electricity to protect the wiring from overheating. When I was growing up, the circuit breaker at my house would trip every time my mom and I were both drying our hair at the same time. So, as you can probably guess... that created an interesting dilemma.

According to Arnold Howard from Paragon, "Breakers trip because both appliances pull more amperage than the circuit is designed to handle". With that said, the same scenario would apply to kilns.  Too much amperage "pull" will cause immediate issues with your breaker. And, since we know that the circuit breaker is triggered by heat, Arnold suggests "that you keep your kiln at least 3’ - 4’ from the circuit breaker box".

Other reasons that Arnold says circuit breaker can trip include:
  • Older Circuit Breaker: Breakers can become sensitive as they age. An overly sensitive circuit breaker can trip even when the wires are not overloaded with too much amperage. 
  • Loose Connection: A circuit breaker is triggered by heat. A tiny heating element heats a thermostat inside the breaker. A loose connection on the circuit breaker can cause the breaker to trip prematurely, because heat builds up at the loose connection. Loose connections get hot because tiny sparks form between the surfaces of the loose connection. An unusually warm circuit breaker panel indicates a loose connection.
  • Corroded Connection: This can also trip the breaker, and is more of a problem in humid areas such as Hawaii.
  • Dead Short: This will trip the circuit breaker, because the short causes a large amount of electricity to flow through the wires. Dead shorts trip the breaker immediately after the appliance is turned on. If the breaker trips when you turn on your kiln, open the kiln’s control panel and look for a wire or heating element that touches the kiln's steel case.
If you encounter any of these situations, please reach out to an electrical professional for assistance as you more than likely will have to replace your breaker.  

24 September 2017

OMG... My beloved fiber kiln has a crack!

Aging is never a pretty thing, but just cause your outside is starting to show a little wear, doesn’t mean your insides aren’t perfectly strong! You can always spruce up cosmetic flaws with a little filler. Wait... are we talking about faces or kilns? 

It’s perfectly normal for every kiln to to develop heat generated cracks over time and use. We all know that firebrick cracks, but so can ceramic fiber. As each material heats and cools, it will expand and contract with each firing. This will inevitably cause those pesky cracks. Most cracks in your fiber are minor and mostly cosmetic, but they can also occur on a firing surface on an all fiber kiln. Since the fiber is such a good insulator, those cracks you see on the surface hardly allow any heat to be lost. That is... unless you have a gaping hole to the outside.

If you’re not sure what kind of material your kiln is made from, here’s the lowdown on how can you tell a ceramic fiber kiln from a firebrick kiln from Arnold Howard, Engineer at Paragon, "Ceramic fiber is white, light-weight, and has a fairly smooth surface. Firebricks are porous. A firebrick firing chamber has seam lines where the firebricks are cemented together." 

For fiber kilns, if you are concerned about those ugly surface cracks, you can fill them with a product called Pyrolite E-Z Fill, a refractory adhesive that comes pre-loaded into a caulking tube. 

Arnold’s easy to follow instructions for filling damaged areas of ceramic fiber are listed below... so, go get yourself a caulking gun and let’s get to it!


1) Unplug the kiln. Scrape/sand the ceramic fiber to remove glass, ceramic glaze, or other melted contaminants. Remove as little fiber as possible. If a heating element is located where you are scraping, avoid touching the element.

2) Vacuum the dust from the damaged area. Remove all the contaminant. Otherwise it will melt and embed deeper into the firing chamber. Keep the vacuum cleaner nozzle at least 2” from the thermocouple and the controller. This is to avoid damaging the controller with static electricity, which can build up on the nozzle.

3) Squeeze the Pyrolite into the gouge. Pyrolite is similar in consistency to window caulking. Smooth the Pyrolite with a small putty knife or credit card and smooth it evenly. Allow it to dry before firing the kiln. You can send to level and smooth after the Pyrolite is fired.

I hope this little cosmetic tip helps you spruce up, and makes you and your kiln feel young again!

10 September 2017

Things to think about before you order your kiln!

As we have been selling and shipping kilns for more that 15 years, we have had a lot of experience with customers not being prepared for their kiln delivery... including some truly epic fails!  With that, we wanted to share with you our TOP 10 things to think about BEFORE your order your kiln!

1. Is my door wide enough for the kiln to fit through? 
The outside dimensions are typically six to eight inches BIGGER than the inside dimensions. Use a tape measure to ensure the kiln can fit through the door. We hate to see you have to take off the door frame to get it inside.

2. What tools do you need to uncrate the kiln, and do you have those? 
Tools are NOT included. You’ll most likely need a crowbar, an electric drill with a Phillips-head bit, a pair of scissors as these do not come with the kiln, so be prepared.

3. If you don't have friends, family, or neighbors that can help, and you are not capable of unpacking the kiln alone, how will you handle this issue? 
Our free shipping offer covers delivery to the curb and most times the freight driver will be kind and roll the pallet into a garage. But, it’s not always the case. For an additional charge, most delivery companies have a “white glove" service that will unpack the kiln, get it set up for you and even dispose of the trash. If the extra fee is just too much, think about how you’ll handle this issue.

4. Your driveway… Do you live in a rural area with a gravel road or driveway? Do you have beautiful overhanging trees? 
You’ll need to let us know, in advance, so that we can notify the freight company and have your kiln transferred off of the 18-wheeler and onto a smaller truck. Be prepared that the truck could lop those limbs right off, or worse yet, the driver could refuse to drive up the driveway because of them. It’s happened, and it’s no fun. So, if your driveway is a mile long and uphill, and a large panel truck cannot make the trip, you need to prepared to meet the truck at the end of your road or driveway.

5. Are you a residential delivery, but are ordering a kiln that can’t fit on a lift gate because it’s too deep from front to back?
Kilns over 24” from front to back can be too large for the lift-gate, requiring loading dock only delivery. This means you’ll need a friend with a fork lift. Do you have a friend with a fork lift?

6. Did I check to see how much electrical capacity is available on my breaker box before I ordered the kiln?
Make sure you have the electrical capacity you need BEFORE making your decision. Don’t assume you’ve got what you need. Ask a person in the know, or call a professional.

7. How far is the breaker box from where the kiln will be plugged in? 
The further away you are from the breaker box, the more “drag” or electrical loss there will be on the line. This means that the further you are from the breaker box, the less amperage is getting to the kiln. Kilns need all their specified “juice” to run efficiently, so long electrical runs might make the kiln really slow, or even worse, the kiln could fail to make temperature.

And, the most important thing I might ever say... NO EXTENSION CORDS! Kilns must be plugged directly into the wall receptacle to do their job safely. Most extension cords are not rated for the amperage necessary to run a kiln and safety is our number one concern. Beside safety, see the previous paragraph for another reason this is ill-advised.

8. Do I have a dry, well-ventilated place to run my kiln?
Kilns can’t get wet, and moreover, kiln controllers cannot get wet. If they’re wet, they just won’t operate. They could short and be a safety hazard, and nobody wants that. They’re not waterproof like cars, so it’s important to place your kiln inside of a building. A garage is fine, a car port might not be, due to driving wind and rain. An enclosed porch may be okay, but a screen porch might not be for those same reasons. A balcony may be fine to run a kiln, but how will you handle a hot kiln if rain starts during a firing? This may see obvious, but it’s not always clear to some. Be careful and make sure you protect your investment by having a clean, dry, safe place to operate the kiln.

9. Ergonomics... Can a stand be too tall?
A tall stand is great if your tall, but if your on the shorter side, will ordering that prevent you from touching the bottom of your kiln? Yes, folks, this actually happens. Think about your hip height, your arm length and your eye level when ordering the kiln. Will its size, shape and configuration allow you to best operate, load, clean, and unload the kiln? Will how and where you place the kiln allow you to get to all parts of it for servicing, cleaning, and placing and leveling your shelves, molds, etc.?

10. Is this a safe area for my kiln?
Kilns need to be placed on a heat proof surface. Carpeting is a just a disaster waiting to happen, so go get yourself some concrete/hardy backer board from a home improvement store. Wooden tables are also a no-go. You can use large ceramic tiles on those and concrete board to ensure your safety. If you have animals, consider the kiln room a “safety zone”... no animals allowed! Lastly, make sure you place your kiln in area that is well ventilated, so closets and pantry spaces aren’t a very good idea.

03 September 2017

High Heat = Shorter Life Span

Unfortunately, it's true... All those pesky parts inside the controller box with prolonged exposure to high heat, will have a shorter lifespan. And, if you don't have solid state relays, those mechanical relays inside the box when exposed to high heat will be more prone to locking in the closed or on position. So, what is high heat, and how can I prevent it to ensure a longer life for my kiln?

Many studios have kilns located in areas without environmental controls and poor airflow (This is a fancy way to say no air conditioning.), which causes the ambient temperature to be well above 110°F... a.k.a. high heat! This is especially true for those us of with kilns located in the garage. This is hard
not just on the relays but also on the digital controllers.

To counteract those high ambient temperatures and improve the lifespan of your controller, we suggest using a fan to blow air across the electric components. It doesn't need to be a large, industrial fan. Just a small, four to eight inch fan on low speed will be very effective. We use a personal desk fan and it works perfectly!

25 August 2017

What’s the difference... Kilns vs. Furnace vs. Oven?

Proper heat treatment is an essential part of knife making, tool and die work, and parts fabrication. Without precise control of time and temperature, blades won’t hold their edge, and tools and parts may be too soft or too brittle for use. Buying a heat-treating kiln, oven or furnace can be a complicated process, but our job is to make it easy to navigate the decisions involved in finding the right one for your needs. Here’s some basic information to help you decide which is the best choice for your professional or hobby needs.
So, what is the difference?
For our purposes, all three of these names refer to a fireproof box that gets hot. No matter what you call it “the box” needs to have the capability to get to the desired temperature and stay there for the prescribed amount of time. It also must to have the ability to heat and cool at the prescribed rate for the particular process required. Most importantly, it must be safe and easy to operate, and last a long time. 
Kiln: associated with the manufacturing of pottery, glass or ceramic ware. These are typically fired from room temperature to a specific process temperature at a prescribed rate of increase and then allowed to cool at a controlled rate back to room temperature. The rate of increase (or decrease) during the firing and cooling stages is often of great importance. Items being fired are seldom removed from the unit while it is performing. There may be periods of time when the temperature is held during the firing but the hold time relative to the total firing time is usually insignificant. Temperatures range from 1700° F – 2350° F. 
Furnace: associated with forging or heat treating metal. These are typically HELD at a single temperature for an extended period of time. The exact rate of temperature increase during the heating stage is seldom of importance.  Items being fired are often added to or removed from the furnace when the unit is hot. There are typically long periods of time when the temperature is held during the firing, and there may be multiple cooling steps and hold times for processes including annealing, case hardening, and tempering. Temperatures range from 2000° F – 2450° F.
Oven: associated with drying or cooking, are the same as furnaces except the usage temperature range is lower. The lower temperature rating often means a large chamber can be powered with lower amperage. Temperatures range from 250° F – 900° F.
It really doesn’t matter what you call it…. As long as it does what you need it to do. From this point forward, we’re going to refer to all the options as KILNS. What you really need to know is how much space you need, what temperature do you need to get to, and how long does it need to hold at that temperature. Here is a link to a guide that you can use as a reference: The Heat-Treating Data eBook.

Now, that we have that figured out...  you need to think about:
What size do I need? A basic aspect to consider when choosing a kiln is its interior dimensions. Kilns for making knives are considerably smaller than other types of kilns because of the smaller size of the average project. Kiln size reduction helps to reduce costs as well as improve heating times. Determine the size of the largest blades you intend on creating and make sure it can fit inside your chosen kiln. It also depends on how big you want to work. There’s nothing worse than buying a kiln that you outgrow in 6 months. Think about the future and what you might grow into.

What temperatures do I need? Necessary temperatures are determined by the type of metal you work with, so make sure of your own requirements before buying a kiln. Check the above reference guide if you still have questions on heat treating temperatures.
What amperage does the kiln need 120V vs 240V and how many amps will the unit draw? Based on the size of kiln and top heat requirements, each kiln’s voltage requirements and amperage needs vary.

12-Key Controller
What type of controller do I need? A kiln controller is the brain that tell the kiln what to do, and when to do it. They range in simplicity, ease of operation, and price. Most of our heat-treating kilns have a variety of controller options that are determined by the manufacturer. Not all controllers are available through all manufacturers.

What safety features should I look for? All heat-treating kilns we sell have available door shut off devices cut power to the elements but leave the digital controller energized to resume the firing program as soon as the door has been closed. Check to see if your model has these included or if this is an add-on option.
Finally... the MOST important question. Which kiln series should I purchase?
Evenheat HT-1
The Artisan, Cubed and HT Series... The Artisan 688 is perfect for small, pocket folding blades. The Ten Cubed is larger and also designed for folding blades. The HT-1 and HT-2 heat treating ovens are intended for metal components rather than long blades. Check the electrical needs and top temps to ensure you’re getting exactly what you need as these models can vary.

KO Series... These kilns are for those needing even higher temperatures. This series has thicker wall insulation which allows the kiln to reach temperatures of up to 2400° F. The 240v requirement makes it perfect for machine shops and very ambitious hobbyists. Read more about our most popular KO heat treating oven, the KO-22.5

Evenheat KO 22.5
KF Series... These kilns have a top temperature of 2200° F but offers more capacity than the KH series. Our bestselling heat treating oven, the KF-18, has twice the interior dimensions as the KH-418 and three times that of the KH-414. Running on 240v, it’s perfect for small machine shops and the more ambitious hobbyist. The KF series represent our most popular sellers. 

KH Series... These kilns are perfect for hobbyist knifemakers working out of a residence. Running on standard North American 120v and using a standard household plug, it can be set up anywhere in the home. Despite its low weight and smaller interior chamber, KH series ovens can heat up to 2200° F. Read more about the KH-414 and KH-418 series, our most popular KH heat treating ovens. 

PMT Series… These kilns have swing doors and are available in both 120V or 240V models depending on size... from the PMT-10 to the PMT21. The PMT series is rated to 2350°F.
KM and PKM Series… These kilns have drop down doors and are available in single width or double barrel width, and are available in both 120V or 240V models depending on size. The KM-series kilns like the KM-24T are long and narrow, ideal for knives.

Last but, not least... What accessories or options do I need?

Mechanical vs. Solid State vs. Mercury Relays
Relay upgrades are another important safety and convenience item to consider. If you don’t already know, a relay is the part of the kiln that controls the power or current to the element, allowing the element to either receive current and get hot, or to interrupt the circuit thus not allowing the element to receive current and cool down. The mechanical relays, which come standard on all kilns, are what is responsible for the ubiquitous opening and closing clicking we hear while our kilns run.

ALL MECHANICAL RELAYS in U.S. kilns are virtually the same... no matter the manufacturer. 
Solid State Relay
Mechanical relays have a life of up to “X” clicks and then they fail. We know that all failures stink and that is why we recommend changing your relays every 12-24 months. If you are a heavy kiln user, you should be smart and change your relays once a year. If changing relays this is something you don't want to hassle with, you can eliminate the problem by upgrading to mercury or solid state relays and almost never (they last up to 15 years) have to change a relay again. In our opinion, it's one of the best upgrades money can buy!
Drop Door vs. Swing Door vs. Guillotine Door
Check which door is available for the kiln you choose. One door isn’t “better” than another, it just your preference for ease of access to the items inside the kiln. Drop doors facilitate the removal of items from the hot kiln so that the door does not impede access.  The drop door requires a single action of a counter-weighted hand control mounted to the left of the kiln chamber.  A safety chain prevents the door from opening too far and stressing the hinge assembly. A Guillotine door is an alternative to the drop door and slides up versus folding down. Swing doors open side to side to facilitate access to the items in the kiln.

Orton VentMaster
Downdraft Kiln Vent
This is typically used for specialty industrial heat treating processes as well as specialty burnouts for diesel engine parts, so for a hobby knife maker, this is likely not something you’ll need. Depending upon what type of metal you are heating and the ventilation of the area you are in, it may be useful to vent the kiln away from your work space due to gases produced from industrial products fired in the kiln.  As a side benefit of venting, the increased flow of atmospheric oxygen may improve reactions within the kiln.

Gas Injection Flow Meter
This is typically used for specialty industrial heat treating processes, so for a hobby knife maker, this is likely not something you’ll include in your purchase. Gas injection can be very important with heat treating metal to prevent oxygen scale from developing. Oxygen in the furnace forms a scale on the surface of knife blades and other parts during heat treating. To avoid surface scale, wrap the parts in
Glass Flow Meter
heat treating foil or inject an inert gas into the furnace. The gas displaces the oxygen. Please note that the gas may reduce heating element life. Also, gas injection does not offer better results than heat treating foil nor does gas injection prevent all scaling. The main benefit of gas injection is the savings in time over wrapping the steel in foil. The flow meter can be ordered with an optional solenoid kit, which enables you to turn the gas on or off for each segment, or stage, of the firing.

Hope we didn't overwhelm you with too much information... If you still have questions, as always... just give us a call!

15 August 2017

Show Your True Colors!

What is your favorite color... Pendant Blue, Salsa Red or, maybe it's Mancini Pink?

For a limited time, Kiln Frog is offering FREE COLORS on the Evenheat Fishbone and Kingpin 88 kilns!

 Yep... I said it! FREE COLORS! That's a $50.00 savings. So, what are you waiting for?

How do I test for accurate temperatures in my kiln?

In case you don’t know, a thermocouple is the nubby, sticky-outie thing inside your kiln that takes the temperature and reports it to the controller. This is a picture of what your thermocouple looks like inside your kiln.

I had a great conversation about this with Jim Simmons, Production Manager at Evenheat Kilns. He said, “Most manufacturers tell customers that a variance of +/- 20F degrees is an acceptable target to stay within the temperature range.” But in my experience, most of us usually can adjust within about +/- 50F degrees and still be able to accommodate the changes.

He also said, “It’s time to change the thermocouple when the room temperature reading is OVER 50F degrees above or below the true room temps. A thermocouple offset is also an option that your manufacturer can walk you through.”  In my opinion, changing out a thermocouple is an easy and less expensive thing you can do to keep your kiln singing along. For most manufacturers, a thermocouple is in the price range of $35.00.

He was pretty specific about this one point, “When thermocouples wear out, you begin to get an “over fire” situation, which means the temperature of the kiln reads LOWER than the actual firing temperature in the kiln. If you don’t change out your thermocouple soon, it’s just gonna get worse.”

This is actually happening right now with one of my kilns. It’s 8 years old, and gets quite the workout! The controller is reading 1325F, but the firing results really look like 1425F. This is a clear sign that it’s time to change out that old thermo! I’ve been lazy about it, even though know I need to do it. Like my hero Maya Angelou said, "When you know better, you do better!"

Jim shared this last tidbit... we love Jim, but it’s pretty techie stuff…

“Here’s the technical formula. The air in your kiln, plus the tip of the thermocouple -2 degrees or .4% of temperature, whichever is greater, that is the temperature differential  between the tip of the the thermocouple to whatever material you have in the kiln. Temps are measured by millivolts on the tip of the thermocouple. Who knows (the engineers know) how that really works for us everyday “Joes,” but you could get another digital pyrometer, drill a hole next to the other thermocouple, and place that in the kiln. One thermo would them prove or disprove the other thermo, as long as the first thermo was calibrated correct at the factory. There’s really no way you could accurately do this in the studio or shop.”

Well, there you have it. It sounds like we have three options:

  • Manually do the adjustment and change your programs accordingly to accommodate the +/- temp factors of your particular kiln.
  • Call the manufacturer and have them walk you through a thermocouple offset on your controller.
  • Do what I’m doing! Send the $35.00 dollars and change out the thermocouple.

Good luck! And, may all your temperatures read true!

24 July 2017

Paragon Distributor News: The Improved BlueBird XL Bead Kiln

Hot off the press... Paragon Kilns has just announced improvements to one of their most popular kilns... the Bluebird XL. The new Paragon BlueBird XL has an improved ceramic fiber roof, thicker doors with new gaskets, heavier mandrel holders, and a stainless steel control panel.
  • Improved Ceramic Fiber Top - The BlueBird XL features new sinusoidal “wavy” elements, which are embedded close to the inner surface of the high-tech, vacuum-formed ceramic fiber top. This is an improvement over our earlier embedded coiled elements, because the “wavy” elements are mounted closer to the surface. This enables the elements to radiate heat faster for longer element life. The ceramic fiber top reduces dust inside the kiln.
  • Improved Double Doors with Gaskets - Both doors are 3 1/2” x 10” and mounted in a 4 1/4” high opening. The 3/4” gap under the doors is filled by flexible, high temperature door gaskets, which help to hold in heat. The 2” thick ceramic fiber doors are twice the thickness of our original doors. The hinges are now continuous across the top for extra longevity.
  • Improved Mandrel holders with 20 slots are held with magnets instead of screws - The kiln comes with a single and a double mandrel holder. The single holder supports rods or mandrels from one point; the double cradles the rods at two points. The holders are held by magnets. They are sturdy and heavy for stability.
  • Improved Rare-earth magnets hold the doors open or closed - Rare-earth magnets hold the doors closed while the kiln is heating to annealing temperature. Phenolic knobs on the door handles stay cool to the touch. Use the switch on the front panel to turn off power to the controller when the kiln is not in use.
If you were thinking about ordering a Bluebird XL, now is the perfect time! And, don't forget that you can order all Paragon Kilns in color at no extra charge!

22 July 2017

“What to Expect, When You’re Expecting!”

Waiting for a kiln is like waiting for new a baby to arrive. You have the relief of "I’ve have finally made the decision", and the adrenaline rush of " Now, I’m ready to begin the new adventure.” And then nothing happens… crickets chirp and you wait… and you wait. You are constantly checking your e-mail waiting for the tracking and delivery information to arrive in your inbox. For most of us it's like waiting for a pot to boil... the more you watch, the longer it takes.

At Kiln Frog, we understand, and we get it! We recognize that you are dying to know exactly which day it’s coming, and how soon you can get started. And, we know that waiting stinks!

Currently, most kiln companies build kilns to order due to the immense amount of customization options they offer. Only the smallest 120v table top kilns, like the SC3 or Kingpin 88, with the most generic options are built and ready to leave the factory immediately. In addition, the demand for certain types of kilns is so high that the manufactures just can’t keep up. In today’s economy, the manufacturers would rather create lag times for delivery, then bring in more production staff and risk layoffs. Additionally, kiln building is a relatively specific skill. A lot of training is required to be knowledgeable and proficient, and that takes investment too. So, we all prefer that the kiln companies take their time and build ‘em right! 

While you are waiting, here are some things you can do to be ready when the kiln arrives:

Make space for your new baby to live. Plan for 12 inches of space between the kiln and everything else. Make sure the space is clean from dust and debris.

Clear a space for the box/pallet to live while you are unpacking the kiln. Chances are the freight company or even UPS/FedEx, etc. will place the pallet or box in your garage, but you will need to have a covered, clean and dry space ready so that you can take your time assembling things like your stand, etc. Some models come with stands assembled, and some do not.

Get yourself a set of nut drivers and a multi-meter from the home improvement store. You’re going to need them if you’re ever going to do any maintenance on your kiln. You might even need the nut drivers to put together your stand.

Make sure the space your planning to put the kiln is less than 6 feet from the receptacle. Most kilns only have a 6-foot cord, and the bigger the kiln, the fatter the cord, making it less likely to bend around corners, etc.

Make sure you plan for a working surface. Somewhere near your kiln to store kiln wash, posts, extra shelves, gloves, tools etc.

Make plans for someone to help you unpack the kiln. Only the smallest 120v table top kilns can be a “one man job.” If you lack the upper body strength to lift 40 pounds alone, prearrange some help. Do this BEFORE the kiln arrives so that you’ve set the stage to get going sooner rather than later.

Have a plan for debris removal. What will you do with pallet? The box, the foam, the strapping, the plastic, etc. That packing material is coming, how will you get it gone??

Pre-read the manuals and watch the controller videos on YouTube. Be familiar with your kiln and controller before it arrives. Maybe purchase some fun technique books to inspire your work!

If you haven’t heard from us in 3-4 weeks, feel free to drop us an email and inquire as to what we know about your kiln. We typically check with the manufacturer at the three-week mark if we see your kiln has not shipped yet.  If there’s a problem, we’ll let you know.

Great service is our #1 priority! We know you’re anxious to get your new kiln and get going, so we humbly ask, please be patient. We don’t build ‘em, and we have no control if a manufacturer gets behind due to mechanical problems at the factory, weather related issues, shipping delays, etc. We want what you want, your kiln in perfect working order, delivered in one piece, in a timely manner...

And most importantly, a happy, happy customer!

06 July 2017

TAP Kiln Control Mobile Update for iOS

From our friends at SDS Industries: An update to TAP Kiln Control Mobile is available for iOS users. Future versions of the mobile application will provide nearly complete control of your internet accessible kiln, with the ability to create new schedules, edit existing schedules, modify settings, and review logs on the go.

Current Release

  • Create TAP Mobile account and add kilns on the fly
  • Remote monitoring with by-the-minute updates
  • Quick check the status of your kilns with easy to read indicators
  • Detail view that shows current execution status
  • Push Notifications for schedule step advancement, firing completion, and error conditions
  • Tab Layout offering view of Kiln specific Schedules, Settings, Diagnostics, and Error Logs

Future Releases

  • Create and modify schedules remotely
  • Remotely update kiln settings
  • Firing Log view with by-the-minute data points
  • Ability to Skip Steps and Abort firings remotely

Please note, TAP Kiln Control Mobile requires your TAP Kiln Controller to be on software Revision 2 or higher. The current software release is Revision 4.0, which incorporates updates necessary for the most effective app experience. For users that are web connected, the latest software version will download automatically when the controller is powered on.

More information on the Tap Controller from SDS Industries.

For technical assistance or questions, please contact info@kilncontrol.com.

25 June 2017

Discoloration on kilns with fiber

Fiber kilns are constructed of rigidized fiber to keep the walls nice and stiff. Some kiln companies pre-fire their fiber at the factory to a satisfactory temperature so that any excess rigidizer burns away while others do not.  As you can never be 100% positive that all of the excess rigidizer is gone, a good fiber burnout is usually necessary.

With that said, before you put anything in the kiln, fire your new fiber kilns up to 1500°F and hold for one hour. Make sure to do this in a well-ventilated area, like an open garage, near an open window or your back porch because as the heat increases, the excess rigidizer may begin to steam, and well, yes even get a bit stinky. We get a lot of calls about this but, don't panic as it is totally normal.

As the process continues, the nice white fiber board may even begin to turn brown and discolor. But, once the temp reaches 1500°F the toasty looking area should return to pristine white. If there is a lot of rigidzer, the area may remain slightly discolored or seem stained.  Again, don't worry, as this will not effect the firing of the kiln, or later, the glass inside.

Discoloration happens a lot when you use fiber papers like Thinfire or Papyrus. It’s just happening inside the kiln, so you don’t see it. If you vent your kiln while using these papers, the burnout process can discolor the edges of your kiln lid. Again, this just isn’t a real problem, just a cosmetic blemish. Think of this as smile lines from the joys of using your kiln!

Learn more about fiber vs. brick kilns...

03 June 2017

Greenery is the 2017 Pantone Color of the Year!

Bullseye Glass Quick Tip:

"It's not easy being green" but, we think that Kermit the Frog would be so pleased with Pantone's choice of Greenery as the 2017 Color of the Year!

According to Pantone, a refreshing and revitalizing shade, Greenery is symbolic of new beginnings. Greenery is nature’s neutral. The more submerged people are in modern life, the greater their innate craving to immerse themselves in the physical beauty and inherent unity of the natural world. A constant on the periphery, Greenery is now being pulled to the forefront – it is an omnipresent hue around the world.

With that, our friends at the Bulleye Glass Co. have created an inspiring set of Fresh Palette Picks that use the Bullseye green styles they released in 2017. Use them in your next project—or create a palette of your own! Each color sample shown is 3 mm (-0030) sheet glass, but consider 2 mm Thin (-0050) sheets, too!

We can't wait to see what you create!

27 May 2017

Free Custom Colors on Paragon Kilns

Did you know that all Paragon Kilns can be ordered with an optional color at no extra charge? Originally, these fun colors were only available on the E, Q, BlueBird, and SC-series kilns but, Paragon realized that everyone wanted to share the love of color! Imagine owning a pink Dragon, right! That would be my dream come true!

Optional colors are berry, black, jade, navy, pink, purple, and turquoise! Please keep in mind that the exact shade may not match the color shown on your computer because of the variation in color on digital devices. Paragon uses a high temperature water base paint because of low emissions during spraying. This creates a healthier environment for their employees and cuts down on pollution.

21 May 2017

We’re in love with Bullseye's Tint Overlay Palette!

Bullseye Glass Quick Tip:

Have you ever watched the show "Say Yes to the Dress"... well, that how much you are going to be in love with this new Tint Overlay Palette from Bullseye Glass! And, it is so easy!

For a semi-matte finish and crisp seams, simply design with a base layer of tint glass and cap with an opalescent style. To keep the finish, slump with the shelf-side facing up and work with molds that require relatively little heatwork.

06 May 2017

Hake Brush Hack

We love Bullseye Glass Blog Posts and this one is genius!

Connect a full size/standard brush (5.5″) to a short section of another brush (they’re perforated or maybe you already have a broken one) with hot glue & duct tape. Voila! Having a variety of widths in the studio is handy for different applications. Just make sure that the wide one still fits in your primer bucket!

27 April 2017

Google Reviews

Trying to stay up-to-date with social media can be a daunting task. So, today we are asking for a little help from our friends. If you have purchased a kiln or, had a positive interaction with Kiln Frog, we are reaching out to ask if you could give us a review on ‘Google +’. We appreciate it can be time consuming but, it would be a great bonus to us.

Many thanks!