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  1. Kiln Not Firing To Temperature?

    That makes sense. I will try adding some external rockwool insulation, it looks like I'm loosing about 400w through the outside at 2000f.
  2. Kiln Not Firing To Temperature?

    Cool! I just ordered new elements.I just got a bunch of Cone5/6 glazes, is the main reason to not go to Cone6 is that it will be difficult due to being underpowered? I assume all the same series of kilns have the same bricks and it has 3" insulation. I noticed the smaller models have the same power rating. Here is my temperature profile (I slowed it down a lot due to trouble following a faster one as early as 1700 degrees): I would be suprised if thermocouple isn't working correctly, they are very simple devices and I'm using a digital reading chip. The cone5 cone didn't bend fully. Only 1V is dropped over the SSR. Once I swap out the elements and confirm it is working; I will speed up the higher end area of the profile.
  3. My small test fire 120V Cress BT911T kiln is not firing to temperature. I have always noticed it fired slowly, but firing to cone 06 it got there eventually. I recently tried firing to cone 5 and I could not get above 1960 degrees fahrenheit, and going from 1900 to 1960 took 5 hours. I'm controlling the kiln using an SSR, reading temperature with a K-type thermocouple through a MAX31855 with a PID controller running on an Rpi with a webserver hosted. My kiln elements are measuring at 8.8 ohms, rather than 8 ohms nominal. I am getting 90% of full power. Would this be enough to prevent a full firing? This seems strange to me. I am considering replacing my elements, seeing if that fixes my issues, I am not sure though. Does anyone have experience with these 120V kilns?
  4. Homemade Griffin Grip

    Just my opinion, mind you, but a Griffin Grip is not worth the time to make or the money to buy. Taping on center is soooo much faster (and a skill every potter should have) and for difficult shapes chucks and humps work so much better and don't cost a penny. Jim There have been a few posts on here, about building your own magnetic holder system, for trimming. I forget what they said the total cost was, but it wasn't much. Far cheaper than a Giffin Grip. With that said, I still like the one I bought for my classroom, and have no regrets about buying. Plus it was on sale, for about $130 or so. You have no regrets about buying a giffin grip or magnetic trimming system? I have access to a machine shop and I was planning on cnc milling the plates out of some 1/2" acrylic plate I was given.
  5. I was just now looking at the griffin grips and would it be very difficult to make your own? It looks just like a few spirals, a top plate with some slots in it, and grabbers that slip into the bottom plate? Like I know I would have to think carefully about how they will attach, but I don't think it would be too hard to make?