Guest JBaymore Posted May 24, 2014 Report Share Posted May 24, 2014 What is the maximum pressure that your regulator is supplying on those MRs? (sorry - saves me from looking back through a lot of stuff in message threads) What were you running for pressure (and gas type) on the B-2 on the other conversion? best, .......................john Link to comment Share on other sites More sharing options...
Kristin_Gail Posted May 24, 2014 Author Report Share Posted May 24, 2014 On the MR100s, with the valves completely open on both burners, both gauges read about 5.75 (water column). The B2 was also running on propane, on a single 100-lb tank. My firing notes show the highest I had the gauge reading was 30 PSI. It was a 7 cu.ft kiln. Link to comment Share on other sites More sharing options...
Guest JBaymore Posted May 24, 2014 Report Share Posted May 24, 2014 Thanks. Do you still have the high pressure setup you used to use available? best, .........................john Link to comment Share on other sites More sharing options...
Kristin_Gail Posted May 24, 2014 Author Report Share Posted May 24, 2014 Yes, I have the whole thing. Regulator/gauge, hose, and the valve (I don't know the name for the valve), burner. It does not have a Baso valve - I only have one of those; it's on the pilot that's attached to the MR100 in the photo above. Link to comment Share on other sites More sharing options...
Guest JBaymore Posted May 24, 2014 Report Share Posted May 24, 2014 Can you now give me the inside dimensions for the chamber of that kiln, and the wall, floor, and roof constuction materials (basic description)? (sorry to be a pest.) Easy to do this back-and-forth on here today. You are catching me sitting at the computer working in my CAD program on the design for the anagama that I'll be leading a group of undrgrad and grad students building in August. (Image of one view below.) Doing literal course-by-course design drawings in addition to typical elevation and plan views and some detail drawings. Also overall site plan views and roof penetration drawings for the building company doing the site prep and the kiln shelter building. Ugh! I hate sitting at the computer doing this stuff.......... rather stack up bricks. best, ...........................john Link to comment Share on other sites More sharing options...
Kristin_Gail Posted May 24, 2014 Author Report Share Posted May 24, 2014 Ooooh. That looks like fun - both the design and the coming-soon brick part. You could not be any further from being a pest. The sides of the kiln are soft brick, 3" thick - plus 2" of an unknown soft insulating substance on the exterior. The floor is also soft brick, but I'm not sure if it has this insulating stuff beneath it. The roof is 3" regular insulating fiber. The interior dimensions are 29" high x 27.5" wide x 41.5" long. The hard brick bag wall is 8.5" from the interior wall of the kiln. The front corner of the target bricks is ~5" from the wall/burner ports. Link to comment Share on other sites More sharing options...
Kristin_Gail Posted May 24, 2014 Author Report Share Posted May 24, 2014 I'm absolutely on the edge of my seat! Link to comment Share on other sites More sharing options...
Guest JBaymore Posted May 24, 2014 Report Share Posted May 24, 2014 Sorry...... busy. More later. best, .................john Link to comment Share on other sites More sharing options...
Kristin_Gail Posted May 25, 2014 Author Report Share Posted May 25, 2014 Last night I met up with the glassblower who donated his hard bricks. After sharing my sob story, it sounds as though he'll be stopping by soon. He's a tinkerer. ("I bought a brand new Venturi burner once from Ward Burner. I didn't like what it did, so I took a hack saw to it and made it into a power burner." made me laugh right out loud.) He didn't even think I was completely insane when I said, "Can't I just build a firebox on this thing and heat it completely with wood?" (In addition, his neighbour apparently used to teach ceramics and build kilns? I'm continually amazed at what's around me that I cannot see.) In any event. I'm ready to play with this thing. Link to comment Share on other sites More sharing options...
Guest JBaymore Posted May 25, 2014 Report Share Posted May 25, 2014 So.... no matter what I do with heat loss calcs for those side walls, floor, roof etc. (guessing what the brick ratings and the 1" of "stuff" might be) and the maximum orifice size that the B-2 can tolerate without totally screwing up, I can't get what I was HOPING to have maybe be a good test firing work out. But here's a "second best" possibility. This will require that you accept that a load of pots MIGHT get a little screwed up. Close off one of the two burner ports you have with insulating firebricks in such a way that you can remove them easily later while the kiln is quite hot. This needs to be pretty well sealed. In front of the OTHER burner port, inside the firebox, set up a HARD target brick so that it will deflect more of the flame to the side of the kiln that has the blocked off burner port than what tends to splatter to the same side as the burner port that is open. This will be a total "visual guesstimate" at this point. We'll live with that. Build up a base outside the kiln in front of the open burner port using concrete blocks or something for a "stand" for your B-2 to sit on, lined up properly on the open port. Mount that burner on the open burner port. Hook up the high pressure regulator/hose system to the propane tank and the B-2. Have the kiln loaded. Have the existing MR burner setup on its metal rack sitting by the sidelines waiting to go. Fire up the kiln using the B-2. Follow your normal desired rate of climb for the front end of the firing as you normally would. It is possible that the skewed heat input will result in a side-to-side variation of temperature withing the chamber, but it may not be as bad as we might think. Live with this potential side-to-side variation. Note how the kiln performs in general during this part of the firing as compared to how it tended to perform using the MR setup. This might tell us something. While you'll have far less total BTU gas input value avaialble, you'll have two things that you don't have with the MRs........ good primary aeration so you are realizing that input.... and a bit of kinetic energy availabkle in the flow of material going into the kiln. Better aeration and better mixing in the chamber. Watch the rate of climb (degrees per hour climb). Maintian it where you would notmally want it by adjusting the kiln as normal. When you have reached the point that the B-3's input is maxed out (full high pressure available ) watch what is then happening with the rate of climb carefully. I would expect it to fall off steadily at some point in your firing cycle. Eventually it will reach zero increase, as heat losses thru the refractories and with the exiting flue gases equals the total input. We won't let it go THAT far. And it might surprise you how hot it actually gets before this rate of climb becomes an issue. When the rate of climb falls off to maybe a consistent 30-40 F per hour, shut off the B-2, and close the damper not quite fully. Quickly move the B-2 out of the way, and block that burner port up too. Close the damper 100%. Get rid of the concrete block base for the B-3. Turn off the main gas supply on your tanks. Go disconnect the high pressure regulator, and then hook up the regulator to the MR setup. Turn the main gas supply back on. Pull the IFB blocks out of both burner ports and then put the MR manifold setup in place on the burner ports. Open the damper about 50%. (All of the above needs to be done safely, but quickly.) Then light up the MRs. But do so right to a pretty high setting initally. Boom... lots of flame right as you light them. Valve quite open fast. Becasue of the draft on the kiln and the higher than usual for you volume of stuff coming out of the MRs at that point, that situatioon SHOULD cause them to light with a flame that is seated on the tip outside the mixing tube. Adjust the damper closed to the point you typically might have it in this part of the firing. Watch the rate of climb at this point. If it is not almost instantly resuming a solid climb, turn the MRs up. If is it "jumping" way too fast....... throttle them back slightly. Adjust the damper and primary air as appriopriate for the point in the firing you are at. I'd be very interested to see if this actually solves some issues. If so........ the simplest option for you is to lose the MRs and get an additional B-2 and switch to high pressure gas. And YES you can add a wood firebox after butchering the kiln structure some more. But you know that is adding TONS of labor to your work... and unless you are doing extended firing times with that wood... you'll get little of the look of fly ash and flashing that wood can give. So you'll get lots of the work... and little of the benefits. Not likely something you want to do. Also note here the "Prime Directive" on making changes. Only change one thing at a time! You have already made a MAJOR change in the bag wall structure and composition. THAT should be the first test you do before anything I mentioned. The only issue here with that idea is the backburning problem that might prevent you from doing that. But I believe that you alreay have been firing the kiln with them doing that anyway. So maybe one more firing r unning that way will not be such an issue for you. THAT one you have to decide. best, .......................john Link to comment Share on other sites More sharing options...
Kristin_Gail Posted May 25, 2014 Author Report Share Posted May 25, 2014 John, I so appreciate your taking the time to write out, step-by-step, the fool-proof directions to what can be boiled down to,"See how far you can get it with the B2, then switch to the MR system to go the rest of the way." I need those detailed directions. If it works, I think the second B2 system would run me about $800. But another option mentioned is to build a power burner for ~$200? And it sounds as though this option has a better chance of succeeding? Link to comment Share on other sites More sharing options...
High Bridge Pottery Posted May 25, 2014 Report Share Posted May 25, 2014 I never had the urge to visit America before but now I want to attend your teachings John. This thread makes me a lot happier with my crappy electric kiln. Link to comment Share on other sites More sharing options...
TJR Posted May 25, 2014 Report Share Posted May 25, 2014 I say fire that baby up and see how she goes. TJR. Link to comment Share on other sites More sharing options...
Kristin_Gail Posted May 25, 2014 Author Report Share Posted May 25, 2014 Curtis (the glassblower has a name) came by and said, "Did it get to temperature with these burners?" (Yes.) "Are the burners red hot when they're firing?" (No.) "Are there orange flames shooting out the back of them?" (No.) "I don't get what's wrong. Who cares about the blue flame inside the front of them? Fire it again with these same burners and the new bag wall, and see what happens." Which would satisfy the one-change-at-a-time rule. Link to comment Share on other sites More sharing options...
Guest JBaymore Posted May 25, 2014 Report Share Posted May 25, 2014 You have already made a MAJOR change in the bag wall structure and composition. THAT should be the first test you do before anything I mentioned. The only issue here with that idea is the backburning problem that might prevent you from doing that. But I believe that you alreay have been firing the kiln with them doing that anyway. So maybe one more firing r unning that way will not be such an issue for you. THAT one you have to decide. Link to comment Share on other sites More sharing options...
Kristin_Gail Posted May 26, 2014 Author Report Share Posted May 26, 2014 I do believe Curtis is coming back tomorrow to play "Fire the Kiln" with me. I even promised to make cookies. Link to comment Share on other sites More sharing options...
Guest JBaymore Posted May 26, 2014 Report Share Posted May 26, 2014 I do believe Curtis is coming back tomorrow to play "Fire the Kiln" with me. I even promised to make cookies. I think that is an excellent thing. best, ..................john Link to comment Share on other sites More sharing options...
Roberta12 Posted May 26, 2014 Report Share Posted May 26, 2014 Gosh this has been exciting!!!!!! Makes cone 6 electric look boring!!! Link to comment Share on other sites More sharing options...
neilestrick Posted May 27, 2014 Report Share Posted May 27, 2014 Gosh this has been exciting!!!!!! Makes cone 6 electric look boring!!! Boring, but she could have had a couple of loads fired by now! All kidding aside, this is probably the most educational thread EVER! Link to comment Share on other sites More sharing options...
Babs Posted May 27, 2014 Report Share Posted May 27, 2014 Can someone keep this for posterity, wherever that is, who knows when any of us, and more, will require the detailed questions and advice given here. Should be published. Prob not a frequently asked question but a classic example of the commitment shown time and again by the people with knowledge of this depth in this forum. Only prob with courses is that info like given here unless it acted on and needed at the time often can get covered over by the next semester's course requirements. Thanks again to you guys. Link to comment Share on other sites More sharing options...
Kristin_Gail Posted May 27, 2014 Author Report Share Posted May 27, 2014 Can someone keep this for posterity, wherever that is, who knows when any of us, and more, will require the detailed questions and advice given here. Should be published. Prob not a frequently asked question but a classic example of the commitment shown time and again by the people with knowledge of this depth in this forum. Only prob with courses is that info like given here unless it acted on and needed at the time often can get covered over by the next semester's course requirements. Thanks again to you guys. Yes! Exactly what I keep thinking, over and over again. There aren't many voices on this thread, but I have a feeling there an awful lot of ears - and will be in the future. And how do you ever repay so many people for providing so much assistance? (Also: The kiln is at 700°F. Film at 11.) Link to comment Share on other sites More sharing options...
Roberta12 Posted May 27, 2014 Report Share Posted May 27, 2014 Babs nailed it! It has been an educational experience for all of us. I applaud the experts who have taken time to help Kristen and my hat is off to Kristen for her perseverance and willingness to forge ahead. And for the videos and pictures! wow! A friend and I have been toying with the idea of building a kiln.....I have learned a lot just from this thread.... Kristen, did Curtis come over to play "fire the kiln?" Link to comment Share on other sites More sharing options...
Kristin_Gail Posted May 27, 2014 Author Report Share Posted May 27, 2014 I have not see Curtis, but I am indeed firing the kiln. Blue flame in the throat be damned. (And other, surprise, visitors ate his cookies.) Link to comment Share on other sites More sharing options...
Kristin_Gail Posted May 27, 2014 Author Report Share Posted May 27, 2014 Well then! Things are going much as before. Burners maxed out around 1500, slows down to 100/hr and less from there up. I have, however, managed to get the thing to reduce. Hallelujah The flame is still doing the exact same thing as before. It comes in from the burner, hits the target bricks/bag wall, goes up in that same hard form as it comes out of the burner. Then it hops over the bag wall and finds it way out through one shelf, down between the shelves, and out the flue. A more licking flame again, and it still follows that same path. Here's the diagram I posted before: http://kgspottery.com/MessesMostly/April_2014/t/01.jpg For some reason the forum won't accept my video of the flame as it pours from the one shelf, down and out under the other. http://youtu. be/7k9lFxqSTBo Maybe this will work - just delete the space between the youtu and the .be Is it normal for a regulator to be covered in condensation? Link to comment Share on other sites More sharing options...
Guest JBaymore Posted May 27, 2014 Report Share Posted May 27, 2014 100F per hour when the kiln is also in reduction is a reasonable climb. How do you know it is reducing? What is the temperature distribution looking like at the moment? Any more even than past firings? If you look into the damper slot (without moving the damper.... peeking in there) when the kiln is firing in reduction are you seeing any flame of any kind going past the damper at all? If you look into the chimney clean out port at the bottom of the chimney QUICKLY (without moving the damper and quickly removing the plug brick to look .... peeking in there) when the kiln is firing in reduction are you seeing any flame of any kind coming into the base of the chimney at all? best, ........................john Link to comment Share on other sites More sharing options...
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