South FL WFO

[SteveP]

My oven project seems to be coming along faster than I expected. The foundation was poured last weekend and I spent all day yesterday building the hearth and forming the hearth slab. I still have some more form work to do so that I can have a curved front section of the slab. I decided to use a precast lintel to bridge the hearth opening versus using angle iron. I put additional rebar in it provide extra strength to help support the hearth slab.

[DrakeRemoray]

Re: South FL WFO

Welcome (from a transplanted Miami native...)
Drake

[Breven]

Re: South FL WFO

Nice...looking good Steve. I like the precast lintel...never seen that before.

[RTflorida]

Re: South FL WFO

You can't go wrong with the Cast Crete lintels.....they produce a very good product, they pretty much "own" the market here FL (nearly every home has them over most door and window openings).

RT

[SteveP]

Re: South FL WFO

The precast worked out well. Besides, I did not want to use angle iron as a support and have to end up grinding the blocks so that the iron sat flush. And, since my company sells the precast, I got it at a discount. I also ended up with some gaps in my masonry work b/c one 16" long block is actually 15 5/8" to allow for 3/8" mortar joint while two 8" blocks used together will be 3/8" shorter. I just dry stacked the blocks and ended up with gaps. I hope it won't be a stability issue but I poured the front wall solid as well as the back corners and one center cavity on each wall for added insurance.

[SteveP]

Re: South FL WFO

Well I've made some progress on my WFO. I have finished the soldier course and arch supports and will start on the arch tomorrow. The 10" tile saw I purchased really helped out alot but building the arch support was still tedious. I thought I left enough room between my soldier bricks for the mortar b/c when I laid them out they lined up perfectly, but after I mortared each one, I had to cut the very last brick nearly in half to fit. I also tried to leave a half inch reveal as a door seal and hopefully this will sufice. I have to say that I wouldn't make it too long as a brick mason. Good thing the dome will be covered b/c my mortar job looks horific but should serve its purpose. I also noticed that my fire brick have a lot of variation in thickness. Should I sand them down so that my floor is even and if so, what should I use? I have a random orbital sander I thought about using but not sure as to the sand paper grit.

[Bandrasco]

Re: South FL WFO

Hi Steve, welcome fellow Floridian.

Great job so far. I had the same issue with the fire bricks. Many were up to 1/8th" diff in size; a few were warped and a lot were chipped. I'm about as anal retentive as they come so between that and the German in me that wants everything square, sharp, level, and plumb it was very difficult working with materials that were not the same size, thickness, or dimensions... Especially ones that cost so much I read in this forum that you don't want to sand the surface off the bricks as thats the durable part; if removed the inside will crumble after a while. If you didn't cement your bricks down you can always pull up the low ones and add more fireclay/sand mix under them or pull the high ones and remove some and or sand the bottoms off of them.

Good luck and be sure to post a lot of pictures.

[SteveP]

Re: South FL WFO

I've made some more progress. I built the inner arch (pics below) and 3/4 of the dome (pics to follow). I had some issues making the transistion from the dome to the arch. I got it done and it will work, but man does it look rough. I guess the only way to see it is if someone sticks their head into my oven. I hope no one is that ambitious. I had to use a lot more Heatstop 50 than anticipated b/c I did not taper each brick which left me with larger joints. I believe the instructions call for about 1/16" to 1/8" joint but some of mine were much larger. Has anyone had any issues after firing their oven b/c of the larger mortar joints?

[Breven]

Re: South FL WFO

Steve-

In response to the uneven floor- I sanded mine a little, as most people have. I'm not an expert in the manufacturing of brick, but I don't understand why the outside of the brick is the only sturdy part and the inside will crumble. We all cut these bricks in half- is the cut side going to crumble after a while? No...it's not- at least I can't understand why.

I took adivce from Les and used a belt sander. I got 4 or 5 really cheap coarse grit belts and burned through most of them sanding the floor smooth. I'm glad I did...any lip at the joints and your peel will absolutley get caught. I don't knwo what the general consensus is, but I say sand away.

[RTflorida]

Re: South FL WFO

I agree with Breven and Les, sand away on the floor...just where it needs it. My bricks were not perfect either, nearly impossible to get them all level. To use a lumber term - some of mine were actually warped. The belt sander worked great, I think I used one course belt for knocking down the high spots and a fine one to smooth those spots a bit.
Others sware there is a detrimental effect to sanding (pitting). I can't see where that is true...even if it is, none of my bricks were actually smooth - you could say they already had pits, to me it add a bit of rustic appeal. Les mentions in another thread about contacting the manufacturer of his bricks; they told him there was no difference in the hardness throughout - in other words, the cut face will not pit or spall any sooner than a factory face. I stopped by the local refractory supplier (they sell Carolina Refractories firebrick - which I didn't use). This supplier says they have never heard about the cut face being more susceptible to pitting or spalling and in their experience the only way either would occur would be from continued moisture exposure then heating and from exceeding the continuous duty rating (time and temp) of the bricks.

Sorry Steve, all of my side to side gaps were 1/8" or less and I kept all of the gaps between courses exactly at 1/4". You should be good, though. The plans call for using simple half bricks (no "cut to fit"). As long as your last brick in each course fits snugly and acts as a keystone you will not have any structural issues.

RT

[SteveP]

Re: South FL WFO

The plans call for using simple half bricks (no "cut to fit")

RT, is there a set of plans out there? I was basically using the other builder's pics as a blueprint for my own build. I've read through the forum failry extensively but have not seen anything. I still have about a 1/3 to a 1/4 more brickwork on the dome and I am concerned about the mortar gap due to the bricks now being almost vertical.

[RTflorida]

Re: South FL WFO

Steve,
You need to go to the FB Store (register again for the store - it requires a different password).
then scroll down on the left, click on eBooks & cd roms, They are FREE. Click to "buy" and you will be given instructions/emailed (can't remember which) on the downloads.....there are several other FREE eBooks on there as well.

I have to tell ya, the plans will clarify a lot.

RT

[SteveP]

Re: South FL WFO

Thanks RT. Found the instructions and they are helpful.

[SteveP]

Re: South FL WFO

The dome was finished about two weeks ago but I had to take a break to go on vacation (went to NY City for Christmas - burrrr! FL never felt so great!). Anyway, my dome top did not come out completely round. I was headed for a teardrop shape so I made some adustments but went too far and the top came out somewhat flat, but it's done. I completed the outer arch yesterday and the oven door today (Thanks Ken524 for your door design; I shamlessly borrowed it). I am hoping to finish the chimney support tomorrow and have my first curing fire on Friday.

[SteveP]

Re: South FL WFO

I lit my first fire today and it was wonderful! All of the hard work so far has paid off. I burned about 6 small crumpled pieces of newspaper and the temperature got up to only about 170F on the sides and about 200 on the top. After the fire died down, I put the door in place and will leave it on until my fire tomorrow night. Although it was a small fire, the chimney drew like a champ and no visible smoke came out the front. As I looked into the oven while the fire was burning, I could see the separation between the smoke leaving the oven and the cool air being drawn in. It was really cool! I can't wait to build larger fires.