20 May 2018

Long Blade Friendly Knife/Heat Treat Ovens

Last week, Evenheat introduced their new Long Blade or LB Series of Knife/Heat Treat Ovens. We love them... and, think you will too!

To start, the LB Series has an innovative design as the elements are only located on the sides of the oven. By removing the heating elements from the back, the ovens are able to maintain a more balanced temperature throughout the chamber. So, now you can utilize the entire depth of the oven, regardless of blade length.

The firebricks used in the LB firing chamber are held together using compressive force to form a single piece. They are not cemented together like traditional ovens. This construction technique allows individual firebrick to move independently of each other during the heating and cooling cycles which helps to eliminate breakage.

Another advantage is that solid state relays are standard issue on all LB Series ovens. Solid state relays can be triggered up to 60 times a second compared to a mechanical relay that is limited to about once every 10 seconds. This translates into very tight and responsive temperature control which is crucial when heat treating.

Finally, Evenheat has added two new features to the LB Series... a door guard and a heat trap. The door guard provides protection against firebrick damage as well as reduces the temperature seen at the door and door handle. While the heat trap is a raised machined surface on the door that works as an extra measure against heat loss.

The Evenheat LB Series is available in three sizes... LB 18, LB 22.5 and LB 27! So, if you currently heat treat long blades or would like an oven with excellent heat distribution all the way to the back wall... the LB Series is just for you!

12 May 2018

Dual Media Kilns - The BEST of BOTH Worlds!

One of the main reasons we love Dual Media or DM kilns as they are the ultimate in flexibility! Let's face it... sometimes you just need options!

Dual Media kilns are kilns specifically designed for firing ceramics AND glass. Technically speaking, ceramics and glass can be fired in any kiln that achieves the temperature you need. However, this dual design allows the kiln to reach the high firing temperatures needed for casting, pottery, and ceramics while the lid element is perfect for fusing glass!
Jen-Ken Ceram-a-Glass 2422

The Ceram-a-Glass series from Jen-Ken Kilns is a great example of a dual media kiln. They are top and side firing for glass and side firing only for casting, and ceramics. Switching from one mode to the other is super easy as all Ceram-a-Glass kilns come equipped with a side toggle switch. Simply toggle up for the glass fusing mode up which allows you to fire up to 1700°F or, toggle down for the ceramics/casting mode for up to 2100°F. Some of the Ceram-a-Glass kilns even have 3" brick so you can go as high as 2300°F!

Paragon Janus27
The Paragon Kilns Janus series was specifically designed to fire both pottery and glass. According to Paragon, the Janus name was derived from Janus, the Roman god, who is often depicted as having two faces which faced in opposite direction.

In the Janus kilns, you can easily select between glass and pottery with the flip of a switch. With the switch in the glass position, heat comes from the top elements and the middle sidewall element. With the switch in the pottery position, heat comes from only the sidewall elements.

Olympic Kilns also offers a complete line of Dual Media kilns, plus you can easily add a lid element to any of the HE models! An ON/OFF switch activates the lid element when fusing is desired.

Olympic 1818HE
The Olympic Dual Media kilns are stackable (meaning they are constructed of stacked rings) electric kilns that are designed to come apart so that you can easily move them from one location to another, easily work on one section of the kiln without taking the entire electrical system off the kiln, and increase or decrease the depth of kiln as needed.

So, what else do you need to know if you plan to purchase a Dual Media kiln?

HEAT RISES... When you are using a Dual Media kiln in ceramic mode, only the side elements are firing, BUT since heat rises you are "cooking" the "sleeping" lid element. This high-temperature baking of a "sleeping" element will shorten its lifespan. This is not really a big issue as long as you are aware that you may have to change out the lid coil more often than the body coils. It's just the nature of the beast!

USE OF AMPERAGE... A Dual Media kiln will use more power in the ceramic mode than in the glass mode. As you know, clay needs to be fired at higher temperatures than glass, so it's just physics that you'll be using more power. It's not a tremendous amount more but, something to keep in mind when you are looking at your electric bill.

STACKING vs NO STACKING... Dual Media kilns can hold a lot of stacked shelves when firing clay pieces. BUT, just because it can do that in ceramic mode, doesn't mean you can do that in glass mode. The rule for glass is still... one shelf 6-10" from the top element! This means you'll really need to elevate your kiln shelf to get it high enough to get an even firing. Also, if you keep shelves in your kiln below the one that you are using to fire the glass, the kiln will take longer to heat and cool due to the abundance of refractory material (clay shelving) inside the kiln. Knowing this ahead of time will save you headaches and frustration.

We like to think of Dual Media kilns as the gift that never stops giving! It allows you to explore your artistry without having to purchase an additional kiln. In the end, only you know how much clay vs. glass or casting work you plan to do, so... if you like to keep your creative options open, a Dual Media kiln may just be the right choice for you!

06 May 2018

Why is my kiln ramping so slow?

Sometimes you get a new kiln, program the controller, push start and it just ramps super slow. Many times the cause of this issue is that you don't have the correct breaker installed, the wire size is too small for the electrical draw, or you are just too darn far from the breaker box.

NEMA code states that a breaker should allow for a 10-15% variance in amperage for surges, etc. For example, if a kiln draws 30 amps at a full ramp, the breaker should allow for 33-36 amps of space/variance on the circuit or breaker. This means the breaker needs to be at least 40 amps since there is just NO room on a 30 amp breaker for a 30 amp draw.  Also if the breaker is too small, it can be a fire hazard due to the amount of heat that will be created.

With that in mind, here is a quick checklist of things to troubleshoot:
  • Go to the breaker box.... is the correct breaker installed?
  • Are you plugged directly into the wall receptacle? NO extension cords allowed!
  • What program are you using? Is the ramp speed too slow?
  • Turn off kiln and then on again. Put in a program with one segment... Ramp FULL/9999 to 1500F hold 10 min. How long did it take to reach 1500F? Did it reach temp? (larger kilns take longer to heat than smaller ones. A larger kiln may only be able to heat at 400-500 dph.
  • Do you have a multi-meter to check the voltage of the line too assure you are getting the full amperage you need?
As always, please consult a licensed electrician as they should be very aware of this code and its requirements. Most of all we want you to be safe!!

29 April 2018

The Importance of Spare Parts

This is one of those stories that you don't believe... until it happens to you! 

A few years ago, we had a visiting instructor with a full class of students teaching at our studio when the kiln just decided it wanted to be a rebel. There was a tiny waft of smoke, and then a error signal from the controller. Part of me wanted to freak out and run around the room with my arms waving while screaming expletives at the top of my lungs as this was the only kiln we had that was large enough to fire the student projects. Luckily, I quickly realized that I had an audience so, after a few deep breaths and some positive self-talk, I turned the kiln off and unplugged it.

My first diagnostic step was to use my nut driver to unscrew the box where I saw the little smoke puff. And, yes... I know it's not an extra part but, everyone must have a 1/4" nut driver on hand in your kiln room. So, I opened the box and I see a small area that looks burned. It's the connector that attaches the kiln element to the electrical feed that runs to the relay. There's also a ceramic insulator that looks like it's seen better days, and a dead bug.

To make a short story short...the bug wiggled in, couldn't get out, and in it's frenzy, wiggled around the wire and caused a short when the wire touched the side of the box. This action killed the bug, and fried the connection. I know what you are all thinking... and, yes... we have big bugs here in Texas. This is not common, but it can happen.

Thankfully, kilns these days are made pretty "smart" so the controllers sense when a problem arises and shut the program down. With that said, all I needed now was a new ground connector and a new ceramic insulator. I went to my local hardware supply and picked up some hot tub ground connectors as a temporary measure and found some unglazed bisque beads to serve as my insulator. A few moments later I was up and running again. (I know... who the heck has unglazed bisque beads?)

Here's the lesson learned; Just like with a car, occasionally your kiln will hit a bump, or a bug in the road, and need a minor repair. You CAN do it, if you have some spare parts available. Here's what we recommend having on hand:

An Extra Set of Relays
Call the manufacturer of your kiln and ask them to send you a full set of relays for you kiln... some kilns use one and others can use up to three. That is why you need a full set! The best part is they are cheap. They usually run about $15 each and are worth their weight in gold. They do have a lifespan rated in "clicks." So, keep that in mind as age is less of a factor than usage. You just can't run your kiln with them.

In the time since this happened, kiln manufacturers have introduced Solid State Relay Systems. As we just discussed, mechanical relays wear out and fail at some point but, that is not the case with solid state. Solid state means there are no moving parts, nothing to wear out and nothing to replace. Mercury relays are also an alternative but, they are more costly and include hazards associated with handling mercury if it breaks.

Ground Connectors
Since you're already calling the manufacturer for relays, ask for a few of these too! Again, cheap but worth it.

Ceramic Insulators
You guessed it! Since you're asking for relays and the ground connectors, make sure to ask them to add a ceramic insulator. (Now you sound very knowledgeable and they will be impressed!)

Extra Side Element & Element Pins
Elements can be finicky so, these are a must! The side  elements are usually longer than the top element, but these could be MacGyver'd to be smaller if
you needed to replace your element on top and just couldn't wait to for it to come. These typically run about $30 each. Have a spare on hand, you'll sleep better at night. I know I do!

Thermocouple
This is truly for the die hards! These run somewhere around $45 dollars depending on the company. Again, your kiln won't run without it.

Electrical Tape
Duh! Everybody loves tape!

Pliers, Phillips and Flat Head Screwdrivers, Wire Strippers, Set of Nut Drivers, and a Flush Cutter 
These are basic tools you should have in your kiln survival kit. Pack these along with a shot of tequila for calm steady hands!

An Ohm Meter
Another weird, but handy tool to help you determine whether electrical amperage/voltage are getting to your elements. (Using this is a whole other conversation.) They come with directions and there are smarty pants types on YouTube who can walk you through it. Trust me, you'll need it at some point in your kiln life.

The phone number of someone who knows what their doing 
If you need help, no problem! Or, sometimes it's just nice to talk to some for reassurance.. that's what we do! Kiln Frog's "Kiln Repair Directory" is a great resource of over one hundred kiln repair technicians across the US. When you call them and they tell you to get all this stuff, you'll look like a genius because you already have it.

21 April 2018

Smooth It Out

Bullseye Glass Quick Tip:

In this quick tip, you will learn how to create a smooth, uniform surface on the shelf side of your fired work—not a brush stroke in sight!

First, prepare a kiln shelf with kiln wash or Bullseye Shelf Primer. Once the shelf has cooled, gently buff the surface with a sheet of standard copy paper. Than, just tip the shelf upright with the primer side away from you and tap it lightly against a hard surface to knock off the loosened primer.

This technique is ideal for works with a single base sheet or minimal seams. We are especially fond of the effect on iridized glass, though it’s equally effective on non-iridized opals & transparents. Also, please keep in mind that the buffed surface is delicate. Avoid sliding pieces of sheet glass across it, as primer can collect in the seams.

For easy cleanup, we suggest tapping the shelf onto a piece of butcher paper. And, of course, this should be done with local ventilation, wearing a NIOSH approved respirator.