Longmont, CO new WFO build - casted over sand

[UtahBeehiver]

Since you are enclosing and adding dry vermiculite, your labor resources might be better spent on other aspects of the oven. Your oven is really insulated well. FYI, you can drill some Tapcons into the hearth to fasten your wire to hold down the CF blanket.

[fox]

I rendered mine but left a 4" hole in the very top to allow moister to exit when drying out the dome with small fires, I have plugged the hole now & painted over the whole thing.

[cnegrelli]

Render or not?

[cnegrelli]

Will try the stiff brush method as it's really just stained from Portland.

I got in the bunny suit and did my insulation blanket today. Same brand as Russel had used , but mine was foiled on both sides. The foil came right off, so no problem there. It was 2" and I did three layers. The last one required I use some smaller pieces.

Because I didn't cut the insulation board and firebrick floor exactly to the shape of the dome, it has a jagged bottom circumference. This keeps me from snugging the blanket up to the bottom.
Because I'm building a enclosure, I will fill the bottom well with vermiculite. I hope that's a good plan.

Do folks who build an enclosure ever render over the blanket? I'm tempted just to have that nasty stuff covered and sealed.

[SableSprings]

To clean up, just take the side of your trowel and scrape the floor brick spots...it can be pretty easy to take off "new" mortar materials spilled on the floor bricks. Grinders can get away from you pretty quickly and I think it would be an overkill tool for this job. I suspect a little sandpaper and elbow grease will be quite quick and effective as would a stiff wire brush after the scraping. Another option is to use a chisel and some light tapping with a hammer--that should pop most anything off the cooking brick surface that won't come off by scraping. You don't have to get the floor bricks pristine...if you can't scrape it or pop it off with a little chisel work then it's not going to come off with your pizza. Your goal is really to make it smooth enough that your peel doesn't catch on it. Note that some of the mortar "white" can also be removed with a little household vinegar and a stiff brush.

Hope this helps...

[cnegrelli]

So with the Relative Humidity at 78% yesterday (vs. the 15% we had been seeing, I got some moisture on/in the oven and was able to patch up a couple voids I had found and it seems like it took ok. Will leave covered and moist thru today.

I also mixed up some v-crete and created my thermal break / expansiion joint between the dome and gallery. I used some Ceramic Rope I bought on Amazon that I wedged into the seam, covering from above and below with V-crete. Seems to have hardened up nicely this morning.

Question: I've made a bit of a mess with the v-crete and refractory patching on my floor bricks. Can I give them a light sanding with a portable angle grinder or hand sander? I searched and found some threads but didn't really see the definitive answer on this. What to use for sandpaper or better yet, pads on grinder? Looking to just clean them up, maybe take off some share edges here or there.

[cnegrelli]

I've resisted the urge to barge ahead on this build and will take today to re-hydrate the oven and attempt to patch the couple voids. The Temp dropped today from 96 to 66 for a high, and the humidity is up a bit. So I've currently got both the inside and outside of oven wet, completely covered with a tarp. I also wedged a wet sponge up against the two areas of interest. Will try to keep it very wet for the next few hours, perhaps even overnight, and give it a go.

Delays my tribal need to start some fires..... I've got some other things to do that are all minor and cosmetic, while I'm pumping water back into this oven!

[cnegrelli]

I don't plan to apply a render as I'm building an enclosure, so just some wire crisscross to hold it down. I will down a couple layers at least as I have a lot then end up filling up the enclosure a bit with loose vermiculite.

Excellent advise on the cold shower. My wife is also advocating those for me.

[SableSprings]

Yes, galvanized wire works just fine. I've used both chicken wire and metal lath--both inexpensive and relatively easy to cut & work with. (My assumption is you mean to use a mesh wire not just a single wire to weave back & forth...) Make sure you use a good breathing mask, eye protection (swimming goggles or the no-cry onion glasses work really well), and gloves while cutting and applying the blanket. It doesn't hurt to wear an old long sleeve shirt that's bound for the dump. If it's hot & muggy when you are working with the ceramic stuff, it can make you pretty itchy. Also make sure to keep kids and animals away from the ceramic blankets while you're waiting to cover your finished dome.

After placing, cutting, & fitting the blanket(s) over the dome, it's helpful to try and cut the wire and tie it together as closely as possible over the ceramic blanket (& final the dome shape you'd like). When you put on the base render layer for your stucco, it's nice not to have the wire mesh bouncing around...

You might find it helpful to secure the bottom ends of the mesh to the concrete oven base to help you hold & stretch it while you use pieces of wire to tie it together in place. Don't worry about overlapping or cutting wire mesh sections/pieces too precisely...the wire is just to hold the blanket in place and provide some base structure for the next masonry layer...which covers up any ugly wire work.

p.s. - plan on a first cool, then long warm shower after you've stripped off your working clothes (outside!)...cool keeps the pores closed so soap & rinse takes off any loose ceramic fibers instead of directing them into wide open pores.... Don't stress on this, it's just worth thinking about a little extra protection & cleanup.

[cnegrelli]

Is it ok to use galvanized wire to hold down ceramic blanket (on outside)?

[cnegrelli]

We really don't get much precipitation here in Denver area (unless it's Monday night football). I am doing an enclosure, but it won't be waterproof, and in fact will behave more like a stucco dome than most enclosures. I will probably cover it up for the bigger storms with a tarp. We mostly get sunny and dry.

In fact "sunny and dry (and hot)" is making me wonder about doing the patches above discussed with David.

We've been hovering this week around 95 degrees (35 C) with 15% humidity this week. That humidity is not unusual for us, counter to popular opinion. I'm not sure I can pump moisture in it under these conditions.

[SableSprings]

Mounted anchor plate with high temp caulk. Put my 48" chimney on top and everyone thinks it's too tall. Hmm.
That's the engineer in my. 48" is more draw than 36". Plus I got it on Craigslist for $40. Back to the drawing board I suppose.

I just helped a friend add another 48" of 6" diameter chimney pipe to his existing 48" on a Casa2G90. We added the extra height so the smoke doesn't blow into an upper deck area. Funny to me that when I put the extra sections in place I thought "Wow, that looks really tall!" and after a week I didn't even notice it (other that no smoke in my face during martini time on the deck ). The oven does draw very well and for its height, the extended chimney has proven very stable in pretty strong winds. I think your setup looks great...and when eating pizza from the WFO nobody is looking at the chimney!

If you are planning on covering the oven with a tarp during the winter, think about making it easy to remove the chimney. We leave only the base 24" section, cap it with a bucket and then wrap the oven with a double tarp when we close up the place for the winter. Lots of snow and high winds in their "off the grid" cabin by Hihium Lake, B.C. Canada

[deejayoh]

I hope you are not planning on copying that stand. If it's on wheels that stand is dangerous.

I saw that and agree with you. Had to do a little research to see where it came from, and it sounds like the OP hasn't had problems - but I personally would opt for a little wider base! I was expecting pictures of a Humpty Dumpty oven.

https://community.fornobravo.com/for...229#post225229

[david s]

I hope you are not planning on copying that stand. If it's on wheels that stand is dangerous.

[cnegrelli]

Here's the build I'm going to copy, likely with a dark stucco

. Not sure if I can figure out how to slope the roof. May need my buddy to throw this into a cad program. Building it with metal framing is also hurting my brain...