Author Topic: Homemade "HearthKit" (Read 44656 times)

Steve · « **on:** June 22, 2004, 09:14:56 PM »

See the thread "Pizza Oven Physics" for the lead-in to this topic.

I performed my experiment tonight and the results were fabulous!

I made my own "HearthKit" insert for my electric oven by putting two layers of quarry tiles on a rack, then leaning more quarry tiles against the upper rack to create walls. All of this thermal mass provided stored-up heat energy which radiated back to the pizza which cooked the top and edge of the crust.

The insert worked beyond my expectations. The NY style pizza took only 6 minutes to fully cook. My kids said, and I quote, "wow dad, this tastes like restaurant pizza"...

Need I say more?

Here's my experiment:

Steve · « **Reply #1 on:** June 22, 2004, 09:17:31 PM »

My non-contact infared thermometer reads 566°F on the bottom stone. This is the "conduction" temperature at which the bottom of the pizza will cook.

Steve · « **Reply #2 on:** June 22, 2004, 09:19:46 PM »

The oven's ceiling measured in at almost 700°F!!

This is the "radiant" heat which will cook the top and sides of the pizza.

Steve · « **Reply #3 on:** June 22, 2004, 09:21:00 PM »

Here's my NY pizza cooking. Total cooking time was only six minutes.

Steve · « **Reply #4 on:** June 22, 2004, 09:22:17 PM »

The pizza cooked to perfection in only six minutes. Take a look at that charred crust! It tasted great!!

Steve · « **Reply #5 on:** June 22, 2004, 09:23:21 PM »

Steve · « **Reply #6 on:** June 22, 2004, 09:26:11 PM »

Sink your teeth into that!!

Foccaciaman · « **Reply #7 on:** June 22, 2004, 09:51:58 PM »

Hi ho, hi ho, its of to the get tiles I go.

Awesome, truly excellent Steve. ;DI am excited to get the tiles. Can't wait to get up in the morning. (I am not kidding.)
I am not sure how excited Michelle(my wife) is going to be when she sees what the new oven looks like inside when she gets home though.

How long did you preheat for to reach those temps?

Pierre · « **Reply #8 on:** June 23, 2004, 06:56:14 AM »

Now that's a really great experiment.

Does anyone remember the series of books that started with the title:

"The Poor Man's......."

Would be a great addition to the series !

Steve · « **Reply #9 on:** June 23, 2004, 07:57:49 AM »

Preheat was for one hour.

Even my skeptical wife was amazed at the results. I was lying in bed, almost asleep, and she rolled over and said "that was a great pizza"

Pizzaholic · « **Reply #10 on:** June 23, 2004, 08:11:09 AM »

Guess I need to tile the oven too

What was the oven set at to reach those temps?
Great looking pizza!!!
Thanks for you hard work and experimentation!
Any suggestions as to what type of tiles to use?
Pizzaholic

Steve · « **Reply #11 on:** June 23, 2004, 08:20:30 AM »

I use Daltile Red Blaze Q40 quarry tiles.

http://www.daltileproducts.com/series.cfm?series=48&cat=4#

Make sure that you use "unglazed" quarry tiles.

The quarry tiles should be made of nothing but natural red clay (Dal-Tile confirmed to me that their tiles were safe to cook on)

My oven thermostat only goes to 500°F, but I kept switching from "Broil" to "Bake" and I also kept opening the oven door when the thermostat clicked off so that it would click back on. Even though the door opening let out the hot air, the heating element stayed on and kept heating the stone via radiation)

So, using that technique I was able to get my stone up to 560°F.

Arthur · « **Reply #12 on:** June 23, 2004, 03:40:45 PM »

Excellent!

Steve, couple of questions...

So it looks like you don't put the bottom layer on the bottom-most rack??

Do you think the tiles work better than the stone?

Did you ever try stone on bottom and stone on top?

You switched between broil and regular oven how often?

Steve · « **Reply #13 on:** June 23, 2004, 03:55:47 PM »

I moved the rack up a few notches so that the pizza would be closer to the broiling (top) heating element.

I did not use a stone on top in this test. Maybe next time. I wanted to use the broiling element to provide direct, intense, heat radiation.

When I put the pizza in the oven, after the preheat, I set the dial to broil.

I don't have a pizza stone, but using two layers of tile makes for more thermal mass (most pizza stones are not very thick).

Pierre · « **Reply #14 on:** June 23, 2004, 04:22:13 PM »

Steve, the color and crispness of my New York crust is similar to that what you just got with this experiment. Could the volume of the oven chamber play a role in the results one gets at home?

When looking at the pictures of your oven I noticed the proportions of the oven chamber. Are the tiles 6 inches by 6?

You've got 3 tiles side by side and deep and there is still some room left. Apparently most U.S. ovens are much larger in volume than the ones generaly sold in Germany, or Europe for that matter. My oven has an overall volume of 44 liters or 1.55 cubicfeet. How big is your oven Steve?

The pizza stone I have is just 12.5 inches in diameter and just fits into the oven with very little space left around it. The pizza is thus quite close to the inner walls of the oven. My New York pizza bakes in about 7 to 8.5 minutes.

Your "Hearth" also makes the chamber smaller so that the radiant heat is much "closer" to the pizza but Of course the tiles give off radiant heat much better than the steel walls of the average home oven just like you mentioned in the other thread.

Pierre

Steve · « **Reply #15 on:** June 23, 2004, 08:23:15 PM »

My oven is 22" W x 17" H x 18" D, or almost 4 cubic feet.

Pierre · « **Reply #16 on:** June 24, 2004, 06:43:23 AM »

That's a huge oven. With 4 cubic feet it's almost twice as large in Volume than my oven.

My oven has the following dimensions: ca. 14" W x 11.4" H x 15.75" D

When you open the oven door to place the pizza in, the heating coils have to heat up 2.45 cubic feet more air space and the metal walls of your oven don't give off enough stored or radiant heat to compensate fast enough for the loss. The tiles you placed on the sides decrease the overall volume and provide much more radiant heat.

Maybe you could build some sort of frame to lay the "floor" tiles in and then attach some upper posts where the side tiles can be attached. You can then insert or remove the whole thing easily.

Pierre

Steve · « **Reply #17 on:** June 24, 2004, 07:38:49 AM »

My oven is pretty much typical of those in the USA. And you're right, that heating coil has a lot of air to heat! I am going to do some more experimentation with the setup that I have. My next test is to make a ceiling with the tiles and see what that does.

Pierre · « **Reply #18 on:** June 24, 2004, 04:40:43 PM »

Quote from: Foccaciaman on June 22, 2004, 09:51:58 PM

Hi ho, hi ho, its of to the get tiles I go.

Awesome, truly excellent Steve. ;DI am excited to get the tiles. Can't wait to get up in the morning. (I am not kidding.)
I am not sure how excited Michelle(my wife) is going to be when she sees what the new oven looks like inside when she gets home though.

What did your wife say about the newly tiled oven

or

Pierre

Foccaciaman · « **Reply #19 on:** June 24, 2004, 05:28:05 PM »

it was a definate

I am working on her right now.
I think for the tiles to stay in my oven it will cost me the same price as a commercial pizza oven, in flowers and gifts.