BeanAnimal's 42" build - Pittsburgh PA

[BeanAnimal]

Forgot to upload,

Anyway rained out today and likely tomorrow unless I setup the ez-up (wind dependent)

starting narrowing down veneer stone choices and am looking at natural and some faux stuff like eldarado.

[BeanAnimal]

I was able to get another hour or so in this evening and complete the first full ring over the inner arch.

Simple geometry dictates that if the trammel is used to set the distance from the center (a constant for every brick), then for each brick on the same course, the leading edge to floor distance (cord length) would be the same. I know many folks struggle with setting this course of brick, but keeping it level and circular is not really that hard if you simply measure. Place the brick in the trammel, pad the joint with mortar and bed the brick until its leading edge is the same distance from the floor as the other bricks in the course, you will end up with a perfect circle to build the final courses on.

[fhausback]

Wow, thanks for the great info. The differences over the whole range was much more than i was expecting it to be. I went with the K because they are so readily available, and i have extras in the garage for my smoker.

Sounds like i need to find a bunch of J type thermocouples. They aren't as cheap as Ks, i probably need to prioritize the install for replace-ability.

Also, a custom designed scale does open up more cool options. Names, icons at target temps, Oh S**T! temp, etc...

[BeanAnimal]

Your pyrometer looks very familiar. I totally agree on the coolness factor.

I did try K type thermocouples in mine, and they do work once you adjust the little screw under the 4. Before I buy more, I do need to experiment with the accuracy over the full 1200 degree range. But they do seem to be reasonably accurate up to 450.

my plan is to install thin stainless tubing up to the fire brick locations, and hope a short thermocouple can be replaced in the future. I still need to experiment. I figure I can push the new TC thru with a fish tape. If that doesn’t work, I’ll skip the tubes and install 2 or 3 thermocouples at each inaccessible location. And as they fail, switch to the backup TC.

i like you, am debating the install. Knowing I probably won’t use them much after I learn the oven, it’s only for cool factor.

Unfortunately - Your are not going to get accurate readings by just shifting the scale via the adjustment screw.

A few notes: The "cold junction" (the wiring in the meter) for both probe types are different. I am not sure how this affects the actual reading.

More importantly - the outputs, both being linear, are not the same slope. So you can get it dialed in and accurate at a single reading voltage, and as the temp moves away from that point, so will the accuracy.

Your options

- live with error - dialing in the crossing point where it is most important to you
- print a new scale and install it in the meter - there are plenty of online resources you can use to do this. I have done it with some older simpson meters converted from their original purpose.

I threw a quick spreadsheet together for you with what I would expect the readings to be if you want it.

I will post a screenshot here

First image is millivolt readings to degrees for BOTH types. Kind of useless to compare, as you can't see the effect of adjusting the meter zero point. It does show you how much they differ in output though.



The second chart - I picked a zero point in Degrees F to align the scales (~500 F). So adjusted to match near 500, the error is at the high end, and grows larger the further from 500 you get. So heat Type-K to 500F and adjust meter to read 500F at that voltage.


Third chart is the same as above, but row shifted to match toward the end of the scale instead. No idea how you would accuratly hit 1200 or 1400 to calibrate at that temp. I guess you can pick a cal point near the area you are most interested in. Clearly if you choose near 200F then 1200F is going to be way off and visa-versa.

[fhausback]

Your pyrometer looks very familiar. I totally agree on the coolness factor.

I did try K type thermocouples in mine, and they do work once you adjust the little screw under the 4. Before I buy more, I do need to experiment with the accuracy over the full 1200 degree range. But they do seem to be reasonably accurate up to 450.

my plan is to install thin stainless tubing up to the fire brick locations, and hope a short thermocouple can be replaced in the future. I still need to experiment. I figure I can push the new TC thru with a fish tape. If that doesn’t work, I’ll skip the tubes and install 2 or 3 thermocouples at each inaccessible location. And as they fail, switch to the backup TC.

i like you, am debating the install. Knowing I probably won’t use them much after I learn the oven, it’s only for cool factor.

[BeanAnimal]

I place thermocouples in my build because I thought I needed them to measure thermal mass saturation. I never use them anymore. Just use the cheap infrared thermo gun and visuals ques.

I think in most cases the "I never use them anymore" outcome prevails.



So I purchased one of these - mostly because it looked cool -- It has 8 positions, uses type-J thermocouples and is old. Produced from 1930 on to maybe the late 80s? This unit appears to be from the 50's or 60's given the appearance of the backalite back plate material. They were apparently used for manifold and exhaust temperatures on trucks, and large diesel process equipment.. patent 1,798,896, granted 1927. Anyway, my "must have syndrome" got the better of me and that send me down this path.

[UtahBeehiver]

I place thermocouples in my build because I thought I needed them to measure thermal mass saturation. I never use them anymore. Just use the cheap infrared thermo gun and visuals ques.

[BeanAnimal]

Goodies arrived by fedex this morning ---

I purchased thermocouples from automation direct (8 of them) and may (or may not) begin installing them. I ordered them on a whim, but they arrived too late (easily) place them where I had planned. I am not even sure I really want to deal with them.

The techy nerd in me wants to log temps or at least display them somehow - for no other reason than curiosity. The realist in me realizes that this is most likely a waste of time and money.

• If I place them, then I need a way to replace them, or just understand their limited life and ignore the imminent failures until none of them are any longer accurate or work.
• I plan on a full stone enclosure - meaning I need to neatly design some type of maintenance access (or place only through holes drilled from under the dome.
• As they showed up late - I am not very thrilled about using a rotary hammer drill on my new dome. I would hate to break any brick bonds. I can pre-drill the few courses that are left and place a few sensors I guess.
• The reading device that I ordered is Type-J (much more on that later if I decide to use) and therefore I can only read to about ~1200. That appears to be right on the borderline - and Type-K would have been better, but I couldn't find a meter that I LIKED for type K.

I had not planned on using thermowells. Too much expense and I don't like the idea of metal being mortared in place - as it will expand at a greater rate than the surrounding brick, possibly forcing cracks in the brick faces. The plan was to simply drill 1/4" holes into the brick and place the probes 1/2" from the brick surface at various places - with 1 or 2 probes protruding INTO the oven and 1 or 2 into the floor and/or insulation. These ALL would be loose fit - for easy replacement and would still measure saturated heat fairly accurately.

So not sure what I want to do here. I like the idea but don't want to deal with all of the gotchas. I hate to waste the money already spent, but at the same time hate to waste time on useless rabbit hole. So one way or the other I will need to make a decision today.

[BeanAnimal]

Very nice! Looks so much cleaner than my custom cut every brick arch, lol. I probably spend a full day between planning and cutting arch and dome bricks! Your decision to go with the kit was in no way a bad decision!!! It's still your build! Cheers from Indiana.

You're doing a fantastic job and the works looks plenty clean!

Even with the pre-cut bricks and excellent engineering of the kit, there are still "personalizations" in my imperfection. I think I mentioned it already, but for once in my life, I am trying NOT to be a perfectionist with a large project. It is far less exhausting! I have a full kitchen remodel coming up and will save the insanity for that, which is hopefully the last large scale project I undertake for a long time.

[GreenViews]

Very nice! Looks so much cleaner than my custom cut every brick arch, lol. I probably spend a full day between planning and cutting arch and dome bricks! Your decision to go with the kit was in no way a bad decision!!! It's still your build! Cheers from Indiana.

[BeanAnimal]

Rained out most of the afternoon. I was able to sneak in about 30 mins of work and get the inner arch set.


joints are not perfectly spaced, it close enough. It was good practice for the outer arch. I have a better eel,for then go to get things adjusted and aligned. One brick is slightly leaning to then left. Ohh well.

Very nice arch form in he kit. The markings were a big help for keeping things symmetrical.



still a little cleanup to do before dark

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I set plastic under the form, as it [the form] will not be removed until tomorrow. I hope to have less cleanup of dried mortar.

[BeanAnimal]

Spent some time today connecting the courses to the entry walls and adding a few more courses. Can’t go any further until I set the inner arch.


.

[BeanAnimal]

Got, a few more hours in today. I setup Anne up in an attempt to combat the heat and direct sun.


ez-up in place and working on row. 4 and arch columns


row 4 done... note I have not tied the rows into the entry area yet. Did not want to drag the wet saw out until I need to. Trying to bang out as much as I can systematically.


started row 5... and called it quits for the evening.



another quick view... I set the springer bricks after this and cleaned up for the evening.

[BeanAnimal]

Rained out on Friday. Did get a few goodies in the mail to be revealed later...

I may order the hemlock for the timber frame. Finishing the exterior of the oven under roof would be nice.
i found a regional lumber mill that specializes in timber frame components. Pasawmill.com
there are closer mills and suppliers, but 5 minutes on the phone with these folks, and I am sure I want to do business with them.

[BeanAnimal]

Got another 2 hours in this afternoon and finished most of the third layer. Still very pleased with this mortar, it is very easy to work with.