Hansen Horno

[CajunKnight]

Looks great at this stage. I had to look two or three times at the hearth slab. It looked like it was warped in the pic, but then I saw it was the front curve of the slab. Pictures can play with my eyes sometimes. I am seeing so many great ideas on this forum and cant use all of them. I am glad its going to be a bit longer before I start mine. We have mild winters here so most of my building will be preferred in fall winter and early spring. Summer is just plain hot and muggy here. I really like the herringbone coming out to the landing area.

Now for sanding the orbital will work but the belt will be faster. But be careful with the belt because it can be unforgiving if one gets heavy handed, but you do wood work so you know how to stop that from happening. Work with a dry fireclay mix on top of board to level bricks as much as possible and reduce sanding.

Again it looks great and keep the pics coming.

[SpringJim]

DB, What makes you think you need a sander at this stage?

I used a dry sand fireclay mix under the bricks and then just used a rubber hammer to get it level to the touch. (before and after wetting it) I'm not sure I will need any sanding (time will tell) and because the sand/fireclay mixture has no cement, I think I will be able to "touch" it up later if needed.

[dbhansen]

Originally Posted by SpringJim

DB, What makes you think you need a sander at this stage?

I'm not sure that I'll do any sanding, but I know that's an option to get the floor nice and even. But my bricks seem pretty uniform and smooth, so I'm hoping sanding won't be necessary. Thanks for the input!

[dbhansen]

My progress this week has been ordering supplies and arranging my floor bricks. It took me until today to figure out that there's more than one way (or direction, rather) to do the herringbone pattern, and I realized I didn't lay it out the way I wanted (picture 1), so I took the time to re-do it (pic 2). I think the landing area especially will look better.

The 3rd pic shows the proposed floor surface. What do you think - smooth enough? Or will my peel catch on those small ridges? Of course I'll have to reevaulate it after it's laid out on the hearth and not the garage floor.

[dbhansen]

I mentioned getting supplies, and this is what I have so far:

• 240 firebricks, in 4 car trips. I "stocked up" because the local supplier is running low and I'm worried their price ($1.37 each) will jump up when they have to get more shipped in from Ohio. Two other local suppliers charge $2.50 each for firebrick. The ones I got have lots of tiny chips and pits and some are even slightly warped - is that normal? I assume perfection is not a reasonable expectation (well, maybe at $2.50!).
• Three 50# bags of HeatStop50 @ $80 each. I had to special-order this, and the shipping adds $30 per bag. Hopefully 3 is enough! I can fill in with the pre-mixed stuff, which everyone carries.
• Four panels of 2" SuperIsol insulation board from Armil CFS. I was almost ready to get some Insblock, but I think SuperIsol is a better insulator and better able to bear weight. I wanted to keep it to 2".
• Oh, and 2 diamond saw blades from Harbor Freight.

And I am soon going to get:

• A 10" tile saw, borrowed (many many thanks, Jim!).
• Four thermocouples (KMQSS-125U-6) and extension wires (TECK10-9) from Omega. I will have one of the thermos custom-made to 8" long, so it fits through my hearth (4"), SuperIsol (2"), and into the firebrick floor (2"). Since they have integrated plugs, the stock 6-incher would be too short, and the 12-incher too long (it would stick out into my wood storage area). $165 total. I still want to talk to someone at Omega to make sure these thermocouples will work best.
• A combination infrared thermometer and thermocouple reader, probably this one.

I went to get some foam-core presentation boards to strenghthen up my floor template (which is currently made of heavy paper), and I was amazed at how expensive they are! Like $8-12 each, even the plain cardboard ones, and I'd need several of them. I think I'll cut up some boxes instead, or get a sheet of pink insulation panel ($6 at Home Depot).

Now to work on thinking of a good excuse for my wife when she sees the credit card bill!

[mfiore]

Daren,

Thanks for posting this. Building material options and availability are quite variable in different regions. This summary is helpful.

Thanks

[dbhansen]

If only I were closer to Chicago, where I could get the HeatStop for $50/bag and SuperIsol without the freight charge! I almost made the trip, but after looking at tolls, gas, time off work, etc., it just wasn't worth it to me.

Update on the thermocouples: An Omega engineer said the KMQSS probes will be fine, but he suggested a "TJ36-CASS-18U-6" for the floor probe, so I don't have to worry about hitting the connector with a log or something. And I decided to go with only 3 for now: 1 in the floor, 1 in the ambient air in the dome, and 1 between the dome and the insulating blanket.

[dbhansen]

Bricks are marked for the oven floor. Next step, cutting.

[mfiore]

Daren, thanks for showing the photos of both herringbone arrangements. I don't think I'd have known a difference.

I'm sure this has come up, but when you extend the firebricks out to the hearth entry, is there a problem with them exposed to the elements (rain, freeze, etc.)

[dbhansen]

Originally Posted by mfiore

I'm sure this has come up, but when you extend the firebricks out to the hearth entry, is there a problem with them exposed to the elements (rain, freeze, etc.)

Good question, Mike. I didn't consider that. I'd like to hear some opinions on it. Perhaps the landing bricks will need to be sealed somehow to keep ice from getting in there.

The floor is cut! It went faster than I thought (though perhaps my cuts weren't as precise as they could have been). The plan is to put half-high soldiers around the outside of the floor.

Now I'll have to work on mock-ups for the arch and dome.