Just a real brief post to follow through on the completed arch, pedestal blocks and hearth. Today, my Dad and I are working on the framing for the roof.
The blocks – after they were fabricated from rough granite. I placed them under the arch to check for fit before I trimmed them for real. A lot of work went into these little things, but every plane is square, so that’s what counts.
After they were cut, I set them on the watertable and then Dad stopped by…so I rooked him into helping me lift the arch into place! (truthfully, he is always willing to help)
Now that I was happy about my clearances and fit, I started carving the hearth. This is the raw form I was working with…funny, it had the same corner broken off as the arch did.
After leveling the surface, I used my template and roughed out the shape. The stone is close to 6″ thick, but needed to cut it down to 2 3/4″.
Hearth is cut to thickness then all the chisel and cut marks are leveled.
Finally everything was smoothed out and polished up to 200 grit. I don’t want a polished look, but a honed finish. The hearth is dark in the picture because I just finished wet sanding it.
I took all the pieces down, then re-assembled them using Lexel, which is a clear rubber sealant. It is good up to 200 degrees, I doubt any part of the stone will get that hot because of the thermal breaks…spaces between the vent arch and the oven and granite.
I wanted to use Lexel because it allows for a dry looking joint, but creates a kind gasket which protects the edges of the stone.
Erik rowberg says
Dude that hearth is a tight fit!!
Still cant believe you are leaving this and moving.
Matt Sevigny says
It’s just a thing Erik! If we do leave, it gives me an opportunity to build another.
Matt Humphries says
Hi, the oven is starting to realy take shape and looking nice. Do you usually use mastic to bond your cut pieces? Also what thickness do you keep your joints?
Matt Sevigny says
Thanks Matt,
Mastic? When I hear that I think black tar like material…that’s not what you mean right? I try for the tightest joints possible within the materials limitations with whatever I do. The granite is good for super tight fits without any material between it, but the stuff I used, Lexel, is a clear rubber…good to 200*. If the granite gets that hot, then I am mismanaging the oven. The thermal break and insulation will block the heat from soaking through. Worst case, I get a little melted clear rubber running out from under the arch. The stone is sealed now, and I doubt it would be a problem anyway…there is very little under there. I used it just to act as sort of a gasket during movement, but it probably does very little. There is really nothing bonding the stone but friction and gravity.
Matt Humphries says
Ok I see thanks for the info. I always try and keep my joints 3 mm quess I am not as accurate as you lol. I think I am going to attempted one if these it’s just finding the space. Keep up the good work look forward to your next post.
Matt Sevigny says
3mm is very tight work Matt,respectable indeed. Most of the stonework I do isn’t done as tightly as the granite work on my wfo for one reason..COST! But like I said, I try to keep joints to the tightest width possible.