Printable SpeedFire® ElectricMini™ Instructions (all info below)

---

Please note
All times and temperatures are given for guidance only. They may vary due to a number of factors including line voltage variations, ambient room temperature, air movement and component tolerance variations in the kiln itself. Also, techniques described may need to be modified for best results. In the remainder of this document, the SpeedFire® ElectricMini™ will be referred to as the SFEM™.

 Fires PMC3 & Art Clay 650 in about 30 minutes 
Because the SFEM™ ramps up quickly, the minimum firing temperature of 1290ºF for PMC3 and Art Clay Low Fire clays is reached in about 21 minutes. In the next 9 minutes of firing the temperature increases to 1432ºF. For PMC3 the hold time at 1290ºF is 10 minutes but because of the additional heat it can be fired in less than 10 minutes. Art Clay Low Fire calls for a 15 minute hold time so firing for an period a bit less than 15 minutes also allows the additional heat to achieve appropriate sintering. Silver metal clay cannot be over fired as long as it is protected from melting. Since the SFEM™ is limited to a maximum theoretical temperature of 1600ºF, this cannot happen.

Fires PMC+ in under an hour
The same premise applies to PMC+ as described for PMC3 except the times are a bit different. The SFEM™ reaches 1470ºF in about 35 minutes and after another 25 minutes reaches about 1560ºF. Experience shows that while it does take 30 minutes at 1470ºF, that it takes less than an additional 30 minutes if the ultimate temperature attained is well above 1470ºF. So, the ultimate firing time for good sintering is probably in the range of 45 - 50 minutes.

Fires FastFire BRONZclay™ in coco carbon in about 55 min
We have tested the SFEM™ exhaustively and were quite pleased when we put half dollar coin sized pieces, Struve Test Bar (STB), a 1/2" x 1-1/2" five card thick test strip of FastFire BRONZclay™ in a small stainless steel condiment cup with Premium Coco Carbon and achieved a successful firing. The test strip was bent to a 90º angle with no breaking or cracking. No blistering was observed on either of these pieces. We did this using no controller and no pyrometer. We simply turned the inline switch on and after 1 hr and 15 min turned the switch to off. You may need to adjust the firing time to attain similar results.


Fires PMC Sterling Silver Clay
The firing schedule for PMC Sterling is to ramp to 1000ºF, hold for 30 minutes then allow piece to cool so it can be handled. This step burns away the binders. The SFEM™ can do this step using the optional temperature controller and digital pyrometer.

After burning out the binders the piece is placed in carbon and fired to 1500ºF and held for 30 minutes or more. Note that it says "or more". This means that it is open ended. You cannot over fire PMC Sterling with the SFEM™. Turn the kiln off and allow to cool naturally.

To do these steps you need the optional SpeedFire Temperature Controller and and digital pyrometer.

Time Based Firing

PMC Sterling CAN be fired without the use of a controller and pyrometer.  We have successfully concluded tests using a  Struve Test Bar - STB (1/2" x 1-1/2" x 1mm - 4 cards thick) made of PMC Sterling.  in a small 2-1/4" stainless steel container, Premium Coconut Carbon and a lid.

First, we did the prefire step with the STB resting directly on the kiln base and the kiln placed on the base.  Simply turn the kiln on, wait 18 minutes, and then turn the kiln off.  Allow the kiln to cool to room temperature.  If you like, after the kiln drops to 700-800 degrees you can remove the kiln top - away from you - remove the piece and use a fan to cool the kiln more rapidly.

For the final firing, we put a 1/2" of Premium Coco Carbon in a 2-1/4" stainless steel container, then the STB, then another 1/2" of carbon the put on the ceramic or fiber flat lid. We turned the room temperature kiln on, timed for 42 minutes, turned it off and allowed the kiln to cool as in the previous step.

The STB sintered fully and was bent to a 90 degree angle with no cracking or stretch markings or blistering.  PLEASE NOTE.  This test series demonstrates the ability of the SFEM™ to successfully fire the PMC Sterling Silver STB.  Your times could vary depending on line voltage and ambient temperature. Larger creations may require more time.

General Top Operating Temperature: 1560ºF +/-

For this version of the SFEM™ we decided to limit the general top operating temperature to1560ºF +/- so it can be "plug and play" so to speak, meaning it can be switched on and left to run until its job is done without risk of melting a fine silver creation. We also took into account all silver clay types and the SFEM™ will fire them all except the original PMC Standard clay. Knowing that alternate non-silver metal clays are becoming quite popular this temperature limit allows "plug and play" capability when firing FastFire BronzClay™. The temperature firing charts associated with the SFEM™ show the highest attained temperature of 1560ºF. The reason for the difference is that based on input voltage, the kiln COULD possibly get to 1600ºF but is not likely.

Temperature controllable with optional SpeedFire™ Temperature Controller
The SpeedFire Temperature Controller is an ideal temperature controller for the SFEM™ in that it varies voltage to control temperature as compared the the "infinite switch" found on most manual kilns that alter the flow of current in an on/off cycling. Depending on setting, it is capable of controlling ramp rate as well as maximum temperature obtained. This makes possible the firing requirements of glass and for metals that must be fired in activated carbon. A graph of the temperatures at different settings is provided, but the results you see can vary due to a number of factors as described previously.

Temperature readout with optional Digital Pyrometer
The SFEM™ comes predrilled with a hole at the top to receive the probe from a digital pyrometer so internal temperatures can be measured. The probe should be inserted deep enough so that about one inch of the probe end to be visible inside the kiln. When you first try to insert the probe, the loop at the end of the probe may be a bit larger than the hole in the top of the kiln. While holding the probe close to the end, just apply gentle pressure and rock it back and forth until it enters the kiln. A pyrometer isn't required when firing fine silver clays since the kiln cannot overheat and melt your creations. Being able to note temperatures would be beneficial when firing some non-silver clays and in glass fusing.

First time firing
The SFEM™ is made from ceramic fiberboard that is rigidified with organic materials. During the manufacturing process most of these organics are burned away. However, some may linger. The first time you fire the kiln there may be a little smell, but this will dissipate after the first firing. You might want to consider firing the unit to full temperature outdoors one time before continued use. Simply turn it on and let it run for one hour then turn off and let it cool and that should take care of it.

Handling the kiln top
The handles on the SFEM do get warm, but not too hot to the touch. We strongly recommend that you turn the kiln off and allow it to cool for about ten minutes before removing it from the base. The recommended method is as follows: With the element cover having the power cord facing you, lift the kiln up to clear your pieces or firing vessel and tip it towards you 90 degrees and rest the element cover on a heat resistant surface. This puts the open area of the kiln facing AWAY from you. This will also allow the kiln to cool more quickly. Be cautious when reaching for your pieces or firing vessel as they may still be hot. Consider the use of tweezers, tongs and heat resistant gloves. It is strongly recommended that you work on a heat proof surface such as the optional 8" square ceramic tile. During firing to maximum temperature, the under side of the kiln base itself generally doesn't exceed 200ºF, but it is prudent to protect surfaces from elevated temperatures. View the video online for the ideal opening technique.

Firing in carbon
Limited testing has been done firing non-silver metal clay products. We have successfully fired FastFire BronzClay™ in a small stainless steel container by placing it in the cold kiln, turning it on and then turning it off after 1 hour 15 minutes. The half dollar size piece and the test bar (1/2" x 1-12" x 5 cards thick) fired with no blistering and the test bar was bent to a ninety degree bend and did not exhibit any cracking and did not break. Your results with this firing time may vary. The rule of thumb is to add 25ºF of temperature at a time if not sintering and to reduce temperature by 25º at a time until blisters don't occur. The SFEM™ is more of a time based kiln so the approximate equivalent to the 25ºF rule would be adding or subtracting 5 minutes of on time.

Fusing and Slumping glass
The SFEM™ is ideal for small glass projects! Small projects may not experience thermal shock as the SFEM™ increases in temperature even though it does so rather quickly. Ramp rates for sensitive or larger pieces can be managed with the optional Inland Temperature Controller. Our experience at different settings on this device are evidenced on the included chart. These times and temperatures can vary due to numerous factors. Also, do not fuse glass directly on the kiln base. Use an appropriate ceramic fiber paper such as the 12 pack we offer that are precut to fit the base floor perfectly. We know it is necessary to "peek" at the progress being made when firing glass. Carefully rock the kiln up on an edge. Do NOT lift the kiln up off the base because a large amount of heat could rush out and cause burns. Do not look into the hot kiln for prolonged periods of time as infrared energy is harmful to your eyes.

IMPORTANT - PLEASE NOTE THE FOLLOWING!

• This kiln will not automatically shut off. The on/off switch is in-line with the cord.
• Do not leave the kiln unattended for extended periods of time.
• ALWAYS operate the kiln on a heat resistant surface.
• Locate kiln well away from combustable materials and at least 18" away from any wall or curtain material
• Do not allow young children to use the kiln unsupervised at any time.
• As with any kiln, there are hot surfaces. Assume they are hot before touching any surface to avoid accidental hot contact.
• Do NOT lift the kiln up off the base while at high temperatures as escaping heat could cause burns.
• When firing glass and "peeking" at the firing progress gently lift one side and look quickly then let kiln back down gently.
• We strongly recommend that the kiln be turned off and allowed to cool for 10 minutes or more before moving the kiln.

KILNS GET HOT!
Kilns get hot inside as well as out! Surface temperatures around the kiln at full temperature will range from 110ºF to 280ºF at the sides adjacent to the handles. Also note that the underside of the SFEM™ can get to 200ºF so please make sure you operate the kiln on a heat resistant surface. We offer an 8" ceramic tile for this purpose, but any ceramic tile or other surface designed to resist heat should suffice. To put a bit of perspective on these temperatures, we tested a home waffle iron and found that the top outer surface reaches 150ºF and the middle exposed area reaches 300ºF.

VIDEO:  The suggested way to open and close the kiln...

---

---