36" Pompeii in DC

[Laurentius]

Re: 36" Pompeii in DC

What about having a spray water bottle on hand and spray your bricks, rather than adjusting your mortar?

[rsandler]

Re: 36" Pompeii in DC

More pictures from today's work attached. The first two show an abject lesson in why you shouldn't mortar bricks together when you can't see all sides of the joint (even if it's pitch black on the other side because you're working at night).

One of the things which caused a lot of frustration today was the fact that my bricks are super absorbent, and when dry instantly suck all the moisture out of my mortar, seemingly irrespective of how wet the mortar is. The obvious solution is to soak the bricks (figured that out quickly), but this doesn't help when I'm mortaring a new brick to a brick that I set in place hours ago (for instance, the next course down). Is there any way to deal with this? Just more water in the mortar? I thought that I made my very first batch of mortar too wet, and have been trying to get the adjustment right ever since, and I wouldn't be surprised to learn that I still have it too dry.

[rsandler]

Re: 36" Pompeii in DC

Picked up another 129 bricks yesterday (paid for 125 and got 4 rejects for free), and between last night and today, built my entry arch, mortared the rest of my soldiers, and started on my first dome course.

The arch involved a bit of frustration and heartbreak. Here's what I did last night:



Here's what I did this morning:


Here's what I did this afternoon (D'oh!)



And here's what I did this evening:

[rsandler]

Re: 36" Pompeii in DC

Progress!

I was out of town over the weekend for a wedding, but I cut and placed my insulation last week, and this week in the evenings I've been assembling my floor in place. While the individual Thermo-12 Gold insulating boards are just about perfectly flat, there is was some slight variation in thickness, so I ended up with some edges. I tried putting down some sand-fireclay-water mixture, and quickly decided I was just making things worse :P. So I'll either deal or take a grinder to the edges at some point.

Last night I dry stacked my half-soldier course, then whipped up a couple batches of homebrew mortar to stick a few of them together. Nice thing about the soldier course is that since the mortar isn't holding anything up, its an excellent chance to get all my mortar-related screw-ups out of the way.

After lunch I think I'm going to pick up the rest of my firebricks, and then this weekend this thing is going vertical.

Exciting!

[rsandler]

Re: 36" Pompeii in DC

Ah, okay. Tapering the bottom edge then; that's roughly what I had in mind. I'm thinking I might just take a power sander with course sandpaper to the bottom corner of the lumber.

[UtahBeehiver]

Re: 36" Pompeii in DC

The chamber I talked about is show in this IT pic which I patterned mine after. Look at "grind to a taper" in red lettering.

[rsandler]

Re: 36" Pompeii in DC

On the CaSi: Russell, Gulf, thanks for the input. Sounds like my jigsaw should do the trick.

On the IT: Russell, I'd been thinking about something like that, since I've seen elsewhere on the forum the concern about the bottom edge of the IT hitting the brick when you try to lift it. When you say a "chamber", are you thinking a notch, a taper, or something else? The word chamber makes me think of a little room, and I'm guessing that's not right. Though I had thought about cutting out a rectangular hole in the arm so that my clamp would have more purchase. But that's another story.

[UtahBeehiver]

Re: 36" Pompeii in DC

RS,

You might want to put a slight chamber(say 1/8-1/4") on the bottom edge of the 2X4 where the brick sits. It will help you move the IT as the need to move to the next brick especially since you have no length adjustment.

[Gulf]

Re: 36" Pompeii in DC

A far as PPE goes: I did not suit up in a level A hazmat suit or use a respirator. I did not even wear a Tyvex suit. I did wear a good dust mask, and blew the dust off my clothes before returning to them to the wash.
For the most part on cutting the CalSil: I used a variable speed jig saw (as slow as possible) and kept the work side of my bench downwind of me. I also set my work bench up a little extra distance from the oven. Two other tools I used for various cuts were an old hand saw and a key hole saw.

[UtahBeehiver]

Re: 36" Pompeii in DC

rs,

I used this product and I used a jigsaw with a fine tooth count. I wore a Niosh95 mask, goggles, long sleeves the whole personal protection route. Cuts good but also fragile to any banging around. You will need to protect the CaSi from your toes as you do your dome. Some people poured a V-crete ring, I just slathered on my leftover home brew as I did my build. Good luck

[rsandler]

Re: 36" Pompeii in DC

Picking up my 2" Thermo-12 Gold insulating board tomorrow morning. Will be getting a 27 sqft carton plus an loose 1'x3' board they had lying around. With that much board to work with, I'm planning on making a 4" layer under my oven floor.

Question: How does one cut CaSi board? Besides "with a respirator, long sleeves, gloves and eye protection" (I'm rather fond of my lungs and would like to keep them intact). Is this something you can do with a jigsaw? With a utility knife? Hacksaw? Butter knife? Steely glare?

-Ryan

[rsandler]

Re: 36" Pompeii in DC

Built my Indispensible Tool this evening, from a swiveling castor and some of the pile of scrap lumber I've accumulated in my garage . Removed the axel from the castor (which was only fasten on with a 10mm nut), then put it back in through a hole drilled in the wood. As an added bonus, if I tighten the bolt a bit, the arm won't be able to move up and down, allowing me to lock the tool vertically.

Need to get a bigger clamp to go with it, as all I have are two 6" bar clamps...

[rsandler]

Re: 36" Pompeii in DC

Well, I've made good progress this weekend. Got all my arch bricks cut--and tapered, as it happened (more on that in a moment). Also got my floor cut, saving four whole bricks thanks to Russell's suggestion to use cut-offs for the small bits.

Because of the pentagonal shape, the arch bricks were a pain in the neck to taper. By the time I'd cut one half of one side of all the bricks, and one half of the other side for half the bricks (that is, I hadn't turned any of them over to finish the cut yet), I was telling myself "There's no way I'd do this again. Even though I now need more arch bricks, I'll just leave those un-tapered, this is crazy!" Then after I finished the tapers and dry-stacked the ones I had cut, and saw how nicely they all stack together... Well, I ended up tapering them all, except for a couple of skinny pieces and what will probably be the keystone. This oven building stuff is insidious, I say!

I do think I will abstain from tapering the tops and bottoms of my dome bricks, however. Tight joints are alluring, and I greatly admire the ovens of the folks on here who have gone for the super-tight joints, sides, top and bottom. But from the experience on my arch, having to do a "flip it over" taper on all 250+ dome bricks would drive me batty! I think my "ease v.s. awesome" trade-off is going to fall on the side of "ease" in this category.

Although doing a partial cut taper like vtsteve suggests might be...uh oh, I'm doing it again!

[vtsteve]

Re: 36" Pompeii in DC

When I tapered the sides of my arch bricks, I just took as much as I could get in one pass (turned out to be 3.75" of the 4.5" brick") and let the mortar joint be a little larger at the outside arc. If you choose to taper, a *dry cut* blade works better - you can run it wet for better life, and they tend to be thicker/stiffer so they don't deflect as much.

[UtahBeehiver]

Re: 36" Pompeii in DC

RS,

In addition what Gulf said, the some of the rollers have a metric hex that threads into the body of the table with a rubber bushing. Check to see if they are adjusted properly, too tight roller won't turn, too loose table is wobbly. I dug this out of my files, here's a one pager on track and blade adjustment on HF saws.