paragon f420

[mason on fire]

so i just got a new kiln!! been working outta one i got at savers for 100$ 5 years ago finally was able to upgrade got it yesterday, on Halloween!

the question is about the clicking. It clicks every 10 seconds then 4 seconds then ten again. im sure its the relays. turning on and off for holding the temperature at 1100. wouldnt it make sense for it to heat up to 1110 then cool to 1090? cut the clicking down like mad right?

its driving me crazy why spend this kind of money on something that will be clicking at me constantly while im trying to work.

am i just doing this wrong?

well im happy its staying around 1100 and i dont have to keep going between med and high to maintain temp. but come on!


mason
friendly fire glass

[faded]

My exhaust fan spins, and spins, and spins, ... makes me hella dizzy.

[art vandelay]

its supposed to do that. if your running your torch you shouldnt hear it too much

[mason on fire]

i like being dizzy ;)

and its louder then my torch. when my music is up i can kinda not hear it but its pretty loud.
all i know is if i spent this much on a stove i would have a word to say with the designer....

[mason on fire]

and does anyone know a good program for to run for glass work? cooling down wise. or just end program i read that it cools 300 per hour? is that right? is that good enough to properly anneal glass?

[art vandelay]

http://www.talkglass.com/forum/showthread.php?17917-kiln-temps
http://www.talkglass.com/forum/showthread.php?48343-Garaging-Striking-Annealing-schedule-will-this-work
here is a link for kiln cycles and temps.
lots of great info in the newbie room

if the clicking gets to loud just turn your icp up louder.

[Wilbur]

Don't garage at 1100 all day

[RioGlass]

I have two paragons that do the same but as other have said between music in the ears, fan and torch I don't notice it. Congrats on your 420. I have had my eye on that kiln for some time.

[brads]

There are a couple of options you have to reduce the clicking, rather than just masking it by turning your music up louder. One of these should be possible, and the other may or may not be, depending on the sophistication and programmability of the Sentry controller the F-420 kiln uses. The timing of the clicking also indicates a problem that you don't know about yet, but will likely encounter in the future. (See "second option" below.)

First option:
Call Paragon and ask if there's a way to change the cycle time of the controller. The cycle time is the minimum amount of time allowed between two turn ons of the power while the controller is proportioning to hold a temperature. <-----(Poor explanation, but the simplest I can think of at the moment.) In other words, the shortest on/off period your controller will allow. Based on the numbers you gave of repetitively clicking at 10 seconds, 4 seconds, and 10 seconds again, yours is set at 14 seconds. (More likely 15 seconds, but the difference doesn't really matter.) The shorter the cycle time, the better the oven will hold a given temperature, but the more often your relay will click on and off.

There's nothing about changing the cycle time in the Sentry controller manual, but it might just be that the manual is dumbed down for simplicity so as not to confuse the average user. Or it could be that the cycle time is fixed and you can't change it. Someone at Paragon should know.

If you can't change the cycle time to a longer interval, I would strongly suggest option two.

Second option:
The loud clicking indicates that your oven uses an electro-mechanical relay to control the power. So the best, relatively easy - but not cheap - fix would be to replace the electro-mechanical relay with a mercury relay (MDR). Mercury relays are not necessarily dead silent, but they are a lot quieter than electro-mechanical relays when they operate. This will reduce or eliminate the annoying clicking noise. And doing this will also provide another, more important benefit. Your relay will last MUCH longer before it finally dies and needs replacement.

An average life expectancy for the contacts of an electro-mechanical relay is roughly 100,000 operations. An "operation" being each time it switches the power on or off. So, set for a 15 second cycle time, as your controller probably is, that means it will operate 8 times every minute. (4 cycles/minute x 2 operations/cycle.) Multiply that times 60 and you have 480 operations per hour. If you work 5 hours a day while the annealer is at holding temp, that comes out to 2400 operations a day - and this doesn't take into account the operation cycles used when the kiln is ramping, while cooling down from annealing temperature.

At this point you may have realized where this is going. 2400 operations/day equals just under 42 days of average life expectancy for a relay with a MTBF (mean time between failure) of 100,000 operations. The ratings are usually conservative so actual life is likely to be longer. But even if the MTBF is 1,000,000 you still can figure you're on borrowed time after less than two years of regular use. Multiply those figures by 10 for a mercury relay.

So it might be worth upgrading to a mercury relay, even without taking the clicking that's driving you crazy into consideration. Paragon probably offers this upgrade, although it's very likely theirs won't be cheap. The MDR option when ordering their F200 kiln is an extra $120. If you know what you're doing it would be cheaper to grab the appropriate MDR off eBay and install it. But if you aren't completely sure about it, then paying Paragon is a better idea.

One other thing. Wilbur is right about not holding all day at 1100F if you can help it. I've met very few people who seem to know it, but holding boro at a high temperature for a long time will cause the glass to start to phase separate, reducing its durability. This probably won't matter too much for those making "artistic" wares. But it's a good thing to know for anyone doing scientific work that needs to retain its chemical resistance. Schott recommends (http://www.vidrasa.com/eng/products/duran/duran_pf.html) a maximum of 2 hours at 550C (1022F) for their Duran 33 COE boro. (Although I suspect that's a typo, and the temperature should be 560C, not 550, which would make it 1040F.)

[brads]

and does anyone know a good program for to run for glass work? cooling down wise. or just end program i read that it cools 300 per hour? is that right? is that good enough to properly anneal glass?

For something with a wall thickness of 1/2 inch, soak at annealing temp for 1/2 hour, then ramp down to 895F over roughly 2 1/2 hours. Go from there to 635F in 2 hours. From that point you can crash cool at 60F/minute. See the link to the Schott info in my previous post for more detail. Annealing info is at the bottom of the page. You may want to extend these times, or alter the temperatures a bit if you're working with colors.