Continued Design Ideas

[brickie in oz]

Re: Continued Design Ideas

Why reinvent the wheel?
http://www.fornobravo.com/forum/f28/...oor-15671.html

[clofgreen]

Re: Continued Design Ideas

It's a thing of beauty! Thanks for the link.

[david s]

Re: Continued Design Ideas

Most ovens have the outer arch slightly larger than the the ineer one so you can fit the door in place. Your arrangement looks like it would be awkward to operate.

[clofgreen]

Re: Continued Design Ideas

Larger as in taller? I thought I read somewhere that the outer opening needed to be lower than the inner to keep smoke from escaping.

[david s]

Re: Continued Design Ideas

Usually both wider and taller. You can make it lower but it will be a bitch to get the door to fit.

[Tscarborough]

Re: Continued Design Ideas

That is the awkward insertion I was talking about (your animation). That is the one thing I would change about my oven. I use a 2 part door. If you can find my original build thread, it shows the 4 doors I have made using perlcrete, refractory, etc. The posted link is 1000 times better.

[brickie in oz]

Re: Continued Design Ideas

The next door I am going to make for the current build will have 1" blanket in it.

[brickie in oz]

Re: Continued Design Ideas

An epic 12 pages and not a brick laid....... ....well done

[clofgreen]

Re: Continued Design Ideas

I'm trying to become an Apprentice. Only 43 more posts to go. (but to be fair, I have layed one brick, put it out on my perlcrete hearth to check level and even-ness.)

Here's one of the threads that made me want to make the outer opening lower than the inner.

http://www.fornobravo.com/forum/37/8...-11354-19.html

True that his oven vents out the back but I've read others who said they had smoke leak problems. Perhaps the best solution is the baffle that Wiley built here.

http://www.fornobravo.com/forum/f8/o...-size-692.html

Anyone else tried the baffle? Seems it would allow me to build my outer arch much higher. I agree that getting a door and a turkey in and out would be a pain.

Craig

[Tscarborough]

Re: Continued Design Ideas

Keep the opening area in synch with the flue diameter/stack height and build a throat and it doesn't matter, it won't smoke out of the front.

[david s]

Re: Continued Design Ideas

Keep the opening area in synch with the flue diameter/stack height and build a throat and it doesn't matter, it won't smoke out of the front.

TS ,How do you mean "in synch"?

[clofgreen]

Re: Continued Design Ideas

I was wondering what "in synch" means as well.

[Tscarborough]

Re: Continued Design Ideas

If the throat and flue offer less resistance then the front opening, the smoke will go up instead of out. If the size of the flue and the shape of the throat are of the proper size and shape, then they would be considered to be in synch with the inner opening. The general rule of thumb is 10-15% of the opening for a flue and the shape should be smooth and with no angles greater than 30%.

[david s]

Re: Continued Design Ideas

Or in other words, a flue that has sufficient draw. IMO 10% is not enough to prevent smoke from coming out the front, especially at start up. I think you need 15-20% with a WFO having the flue at the front and the door separating it from the inner oven, you really can't overflue the design so generally bigger is better.Draw can be increased by enlarging the diameter or increasing the stack height.

[shuboyje]

Re: Continued Design Ideas

I know these figures work in fireplaces but they seem way to small for WFO. Both of my ovens have probably been closer to 80%. My current oven is 42" with an 8" flue. It has an arched door 18 inches wide and 8 inches tall. That comes out to about 112 square inches.

10% = 11.2 square inches
15% = 16.8
20% = 20.4

The 8" flue has an area of 50.24 square inches. What you guys are suggesting is actually a giant constriction in the transition. Just to be the same area as the flue the opening would need to be nearly 45%. I'm sure the numbers are a little better for a higher domed oven with a door big enough for an SUV, but not much. IMHO the opening should be as wide as the door and at least 6 inches deep if you want to get all the smoke on startup.