Wood Fired Beehive in Utah

[UtahBeehiver]

Re: Wood Fired Beehive in Utah

Thanks for the eagle eye. I will watch this from now on, rather I hear now than on the 10th or 11th course. I am working with a much wider brick than normal size 5.5" wide 3" thick 9" long so I have lots of opportunity to split bricks to avoid the small closer. Actually, I think I will redo the second to last one(s) since they are not set set.

Russell.

[UtahBeehiver]

Re: Wood Fired Beehive in Utah

Spent the day working a brick jig to do compound bevel/angle cuts. I think this is a spin of one I saw somewhere on this site but going from memory. I am putting on some urethane on the wood so it has some water proofing and won't swell. I will see how well this works, the proof is in the pudding. The jig is make from junk I cabbaged from aroung the house. The jig is fasten to the HF saw through the 1" holes in the sliding tray with dry wall expanding wing bolts. Used a SS steel piano hinge to make the tilting table and for now just placing wedges between the two wood pieces for bevel angles. Going to try tomorrow.

Russell

[Tscarborough]

Re: Wood Fired Beehive in Utah

When I have to make a series of similar cuts on a brick saw, I use the waste piece from the "model" as the wedge under subsequent brick.

[jlopiccolo2]

Re: Wood Fired Beehive in Utah

Hi Russell,

I just came across your build and from what i saw great job. I just finished my pour for a foundation and chose to put my oven on a angle as well. since i have not seen too many people chose this option, i was wondering if you could share some pics of the build. I am really interested in the your block layout. Thanks in advance...

Joe

[UtahBeehiver]

Re: Wood Fired Beehive in Utah

Hi Joe,

Corner builds are a minority here but it fit my yard the best. Here are some pics of the block layout. Good luck with your build. One thing, when I cut the angles for the wood box, the cut off piece was flip and used in the next course. I was able to get this tight cuts on my 10" HF saw but it takes a little patience.

Russell

[deejayoh]

Re: Wood Fired Beehive in Utah

Clever jig. I like how you turned the brick on it's side to do the cutting. that will make getting it under the saw much easier!

Only thing I can think of is that you might want to put a stop for the outside edge of the brick so you can get the width consistent

[UtahBeehiver]

Re: Wood Fired Beehive in Utah

I am miffed on how to put a stop unless my clamp for the angle can serve two purposes, hold the angle and act as a outside stop as well. I will experiment and report to you guys. PS, this is not my design, I thugged it from one of the other WFOs in this forum, just can't remember who.

Russell

[deejayoh]

Re: Wood Fired Beehive in Utah

Something like this might work. Rig up a piece of wood that would fit over your pivoting part of the jig that can go under the C-Clamp and act as a stop. That way the C-clamp can hold both your pivot angle and your stop position. If you make the lower square of wood big enough, you shouldn't have any problem with it staying in place

[Gulf]

Re: Wood Fired Beehive in Utah

Thanks Gulf,

Going to serious consider removing Foamglas and CaSi under outer arch base course and start arch on concrete hearth.

Working on inner arch today and it is a slow and tedious process. I layed the first course and will post some pics tomorrow. Beer time.

Russell

Russell,
I was out of town for a couple days for a funeral and only home for one hour when I made that knee jerk response. I just returned home from a wedding this weekend and have thought about this very much. When I first started laying out my arch out, I recognized that the arch might be unstable on top of the calsil. With 4" of vcrete to fall back on I decided to transfer that weight to it. In my response I was thinking solely about conserving the heat in the oven and that heat retention in the entry was not necessary since it was separated by the heat break.
However, I did not think about how much heat might be transferred to the concrete hearth (which has gravel embedded). Some gravel has trapped moisture or air pockets. Which ever it is, I have seen gravel pop (explode) in camp fires, and also cause the spaulding which is visible in most house fires on slabs.
Your, concern about building on an unstable foundation for the heatbreak arch is correct in my opinion. I do now recommend that the there be at least 2" of vecrete and or pearlcrcete between the concrete and the "heat break arched entry". I am not sure how much heat can be transferred through the arch to the concrete during nuclear fireups, but some form of a stable insulation would be a good idea.
I still do not think that (with the use of a heat-break arch and floor entry) that the enty has to be insulated to the high standard as the oven. In my opinion the glass and calsil can end at the oven arch. V or Pcrete could be used for the entry. If you decide to remove the calsil and glass for the arch I would do so for the whole entry. At the very least I would replace the glass level with vcrete and step down as I did for the arch. I have layed the fire brick directly to the concrete on many BBQ pits, but never on a fire place, and (since this is my first WFO) never on a pompeii. The amount of heat which can be transferred to the aggreagate in concrete directly through firebrick may not be of a concern, but it is above my paygrade and would like to hear others experience on the subject.

[deejayoh]

Re: Wood Fired Beehive in Utah

Russell
I learned to use Sketchup so I could design my backyard and pizza oven. I guess I am not dragging any legacy of being a draftsman. But you have some mad skills, that is for sure.

On Gulf's suggestion - the compressive strenght of insulating firebrick is surprisingly high. I'd look into that as a stable layer between your outer arch and the hearth. It's not the best insulator (e.g. not as good as Ceramic Fiber board) but it is probably more than sufficient given a) your flue arch is going to be separated from your oven by an air gap and b) the IFB is going to be a couple inches lower than your oven floor next to your glass board. So whatever heat crosses the gap, very little of it will ever migrate down (heat rises and all) to the floor. I doubt you'd ever see 200 degrees where your firebrick met the IFB

here's a site I found with some specs on compressive strength: Insulating Firebrick Physical Properties, InterSource USA, Inc

The lowest grade of IFB has Cold crushing strength of 260lbs per square inch. So if I am understanding correctly, each 9 x 4.5 inch brick will support about 1000 pounds. Put one on each side and your vent can weigh a ton.

[Gulf]

Re: Wood Fired Beehive in Utah

Great info deejayoh,
Beyond compression strength though, I think that we just need to conscider stability into the equation. The 2" of calsil that I had on top of my vcrete may have had the compression strength needed, but it was a little warped and did not set down as tight out in the entry as it did in the oven. Before laying the dome brick I had already installed the floor, which helped it lay flat against the vcrete. We can only use our own best judgement as to wether the components are stable : Are the insulated fire brick touching in all areas, is the calsil laying perfectly flat, etc. In my case, I had two free standing arches constructed before tying them together. They both seemed very stable (seperately) placed on the vcrete. I Think that I read on your build that that you had some conscern about the stabilty of your entry when completed and tied it in with the dome by IFB. I think that is an excellent fix, but I think that it might be unnescesary if it is placed on a stable insulated foundation,
I'm just throwing this in there out of concern.

[Tscarborough]

Re: Wood Fired Beehive in Utah

Compression strength is not really a factor, what matters for using insulating firebrick is abrasion. You can gouge it with a fingernail, so it can not be used in a wear area like the entryway.

[eatingmorefood]

Re: Wood Fired Beehive in Utah

Very Cool. I'm about to stucco a unique Bella C, was made from 90% recycled materials. DIY pizza, Pizza Making Supply, DIY Pizza oven, DIY pizza-ovens, DIY wood ovens, pizza Cutter, Pizza Stones, pizza knives, spice shakers, cheese shakers, crushed red pepper shaker, grill pizza, grill pizza, pizza Q, BBQ pizza, make pizza grill, makin

[deejayoh]

Re: Wood Fired Beehive in Utah

Gulf -
I was kind of thinking that compression strength=stability. IOW, the brick will not crush or deform like CalSil. If I had to do over again, I would have built my arch down to the hearth with IFB - instead of building it on the board with a buttress.

Tscarborough - not sure that will be an issue. If Russell cuts away the CF board and Glass board, the IFB will be well removed from any abrasion issues. It'll be 2-3 inches under the floor. It shouldn't be a wear area.

[Manolo54]

Re: Wood Fired Beehive in Utah

I visited Geneva steel in the early 1980's as a graduate student of metallurgy at the U of U...Was my first opportunity to see a blast furnace in person. Glad to know that some of the bricks are now ending up as WFO's!