36" in Seattle

[jmhepworth]

Re: 36" in Seattle

I cut my floor to fit inside the soldiers. I just traced the pattern on the bricks with a pencil and then cut them on the wet saw. Some of them required two or three cuts to make the curve. But they were all straight cuts.

[ThisOldGarageNJ]

Re: 36" in Seattle

I laid my soldiers on the floor,, no curved cuts were involved....

[Alter ego]

Re: 36" in Seattle

...I have no idea how to achieve curved cuts...

I just cut my brick on the weekend and although they look curved in the photo they are simply 2 or 3 cuts on varoius angles. My oven is 1m dia and at that size a couple of straight cuts is close enough to a curve.

Paul

[kebwi]

Re: 36" in Seattle

Continuation of previous post.

[kebwi]

Re: 36" in Seattle

Cut and laid the floor insulation (3 layers of 1" InsBlock 19). Also cut most of the floor bricks (pics in the next post due to 5-pic limit).

You can see my tile-saw setup, a plastic room masking-taped into the corner of my basement, although the floor is getting a little wet. The pump is in a bucket sitting on the concrete blocks in the back (left image) and the drain in the tray drains into a second bucket at the front (right image). You can also see that I put up a wall of boards behind the saw to keep crud from getting in the pump bucket, which I very quickly realized was a serious problem that would otherwise undermine the whole purpose of removing the pump from the tray to a separate reservoir.

The Insblock 19 was easy to cut with a jig-saw. I use a fine-toothed blade intended for metal instead of a toothy wood blade to minimize "chewing damage". Check out the overkill on the bio-hazard protection. I'll be using that again for the InsWool HP bulk loose fiber for the dome (I'm not using blankets like most people, probably a mistake, but I already bought it, so it's too late now).

The first and third layers of InsBlock have the same layout; the second layer is cut in a different layout so that no seams extend from the top to the bottom (or even past the top layer through the second layer for that matter).

You can see my floor brick cuts in the next post. I am a little confused about the floor bricks. In other people's photos, they appear truly curved. I have no idea how to achieve curved cuts. Are people just making straight cuts and then making micro cuts to "grind down" the subtle obtuse corners...or are other people making actual curved cuts?

[More pics in the next post.]

[MarkHohn]

Re: 36" in Seattle

I have been watching your thread.
You have plenty of rebar in the hearth slab. I think I counted 3 pieces of 1/2" in the lintels, that?s good.
Your concrete was to dry when you poured. (You knew that) You tamped it down with a post. (That was good.) You probably got most of the voids out. You kept it wet after you poured. (That was good) Without looking at it I would think the hearth slab is fine. If you wanted to support the center I would recommend going to pacificindustrial.com and get a 3" or 4" tube or pipe cut to the proper length to support the center of the slab. They will have some scraps of steel plate you can put on top of the tube to give some additional support. Paint it black and wedge it in under the slab. Once you?re done you will be the only on to know it?s there.
For the voids we see on the edges I would not worry about them until you?re finishing the base and exterior. Grouting them with mortar now will not add strength. If you decide to fill them, just get a bag of mortar mix at HD or Lowes.

Mark

[kebwi]

Re: 36" in Seattle

Looks like trusty 'ol Salmon Bay in Ballard has mortar lime, for all you Seattle folks. That's where I got fireclay, and they have huge bags of Perlite, but it's the micro-fine stuff, so I suggest getting the medium grade vermiculite (and perlite) from DeYoung's Farm and Garden in Woodenville instead (I haven't been there, but they're the only place I've found around that has the larger grades in the 4cuFt bags).

The rain in Seattle has been pretty substantial. I have pretty high standards when it comes to deluges since I'm from North Carolina. I've never seen real "rain" in Seattle, but it has been drizzling on very respectable level lately, even short spurts of actual rain.

'course, the heaviest rain I ever experienced in like was in Tikal, like being under a waterfall for thirty minutes straight.

[RTflorida]

Re: 36" in Seattle

From what I have read, there is a difference between garden line and masons lime.you need to look for type s or type n lime.Home Depot and Lowes probably won't wont have it, but will have the garden lime which is not the same. You may have to go to the bricksupplier to get the hydraded masons lime (s or n)

RT

[vintagemx0]

Re: 36" in Seattle

I don't know if "garden variety" (pardon the pun...) has any masonry attributes, but at my local HD store in the masonry section, I've seen Type S and Type N. I haven't used any raw lime on my project, but I did save this link in case I had to study-up;

National Lime Association FAQs - Frequently Asked Questions

Hope that helps.

Did you guys get swamped with rain today? It royally poured down here in Portland.

Regards,

Ken Morgan

[kebwi]

Re: 36" in Seattle

So, you (generically, perhaps slightly toward Neil2) don't suggest using lime in a parging mix? Just 5:1 sand/Portland?

And just to reiterate an old topic, all lime is the same? Lowes and Home Depot don't have lime in their concrete section, only in their garden section. That's the right stuff (for this parging mixture or for homebrew mortar, etc.)?

[Dino_Pizza]

Re: 36" in Seattle

If others think the center expanse seems too wide and you want to add support, what about getting a 36" or so square steel plate, 3/8" or 1/4" thick for under the slab? You can hold it up like Neil says with a single center column or just add a column of cmu's at the rear and front or from corner to corner (diagonally opposite each other) to hold up the steel plate at the edge. I think you just want to take some of the weight away from the middle slab and it should not take much to do that.
I think your steel work in the slab was exceptional so it's got to be strong but, ya...that cement is not as "strong looking" as I've normally seen. I don't know much about concrete so this is just another idea.

[kebwi]

Re: 36" in Seattle

Wow, okay. A few parging references on-line suggest almost 1:1 sand and Portland. Of course 5:1 seems much more typical of other mortars so I find your figure considerably more believable in that respect.

Wet isn't a problem. It's Seattle and it's fall. That means rain every day and fairly humid considering the colder temps.

Thanks for the tip. You said I should parge the entire underside as well as the sides...but not necessarily the top? Doing the sides makes sense to me since they are the most at risk of degradation.

[Neil2]

Re: 36" in Seattle

Go for a 5:1 mortar sand to Portland mix. Or you can buy premix mortar. Before parging make sure your slab is thoroughly wetted.

[kebwi]

Re: 36" in Seattle

Actually, after some research on parging, it looks like the suggested blend does not include lime: just Portland, sand and water, in some combination which I am unconfidently unclear about.

[kebwi]

Re: 36" in Seattle

Ugh, okay. I looked up parging online and it sounds like you are referring to cake-frosting the concrete with a really fine (non-aggregate) concrete, or effectively mortar. So, should I make this mortar out of Portland, lime, and sand, just like the refractory mortar but without the fireclay, or is there some other substance I should use for this task.

At least my rebar is 1/2" on an 8" spacing, so it's much denser steel than most of FB ovens from what I've seen, for better or worse.

As I said before in this thread, I am very confused about how concrete is supposed to work. I concede that my foundation was probably too dry, so I mixed wetter for the core fills and wetter still for the hearth. I mixed it for the hearth such that a glove-full grabbed from the mixer was downright runny because I was so disappointed after the foundation...yet the hearth turned out dry. I am really perplexed, I just don't get it.

At any rate, even before you mentioned parging, I had envisaged something like it on my own. I imagined using a really smooth cement to fill in the rough concrete. I didn't realize until you mentioned it that anyone actually does that. Thanks for the tip.

So, what precisely should I use for parging?

Thanks for the suggestion of a central column too. That's disappointing, it will make the interior space far less useful, but if it has to be done, so be it. I hope I can wedge concrete blocks up in there now. I guess I can angle grind the last block in small increments until it squeezes in. It'll be dry stacked of course...unless you think I should fill the first three blocks with concrete, then make a solid block for the last block, and fit that in place, such that the column is solid concrete.