Author Topic: Silicon Carbide Baking Surface  (Read 19549 times)

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Offline Essen1

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Re: Silicon Carbide Baking Surface
« Reply #25 on: August 13, 2008, 02:54:30 AM »
RN,

Okay. You convinced me.  I'll buy the SiC stone. As a top stone for the new lid first. How do you recommend to cut it into a 15" round shape?

And I'll report back.
Mike

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Offline November

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Re: Silicon Carbide Baking Surface
« Reply #26 on: August 13, 2008, 02:57:53 AM »
What is actually the difference between Nitride bonded SiC and the regular SiC?

There are actually several forms of "regular" SiC, but nitride bonded SiC is different in that to form it a mixture of silicon carbide and silicon additive is fired at around 2500F in a nitrogen atmosphere; while "regular" SiC is fused into various shapes with extreme heat and pressure.

I noticed, unless it's the company's image editor, that the Nitride ones are more pale than yours is.

It could just be lighting.  Attached is an image of a single crystal taken from the Wikipedia article on Silicon carbide.  That is its natural color and shade.  It's like a black diamond.  Different types of ceramic bonding processes may affect the appearance as well.

Offline November

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Re: Silicon Carbide Baking Surface
« Reply #27 on: August 13, 2008, 03:00:46 AM »
Okay. You convinced me.

I'm really not trying to convince anyone of anything.  I'm simply reporting on what this material offers.

How do you recommend to cut it into a 15" round shape?

I would not recommend cutting your own silicon carbide material.  A professional with the proper cutting and safety equipment should be retained for such activities.

Offline Essen1

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Re: Silicon Carbide Baking Surface
« Reply #28 on: August 13, 2008, 03:16:46 AM »
RN,

That's great info! I gotta hand it to you, the more I read your responses, the more I understand...with the exception when you use strictly science speak, though. But then again, I don't think I'm alone.  :)

Anyway, I'll give the SiC a shot.

In regards to the cutting, I'm not going to attempt it on my own. I was just wondering what you'd use to cut it into shape? A diamond cutter, perhaps?
Mike

"Anyone who has never made a mistake has never tried anything new."  - Albert Einstein

Offline November

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Re: Silicon Carbide Baking Surface
« Reply #29 on: August 13, 2008, 03:19:43 AM »
I was just wondering what you'd use to cut it into shape? A diamond cutter, perhaps?

I would follow my own advice.

Offline November

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Silicon Carbide Microwave Oven Baking Surface
« Reply #30 on: August 13, 2008, 07:21:09 AM »
Adding to the ways SiC is being used to increase the speed of cooking, Silar offers the following microwave oven inserts made of a silicon carbide composite material:

http://silarwave.com/products.html

[Note that these inserts are for commercial microwave ovens.]

- red.november

Offline November

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Re: Silicon Carbide Baking Surface
« Reply #31 on: August 26, 2008, 11:09:21 PM »
RE: http://www.pizzamaking.com/forum/index.php/topic,7066.msg60775.html#msg60775

Just to put this issue of electrical conductivity to rest, I measured the electrical resistance of my SiC shelf.  I expected it to be high since I assumed the bonding process would interfere with the usual valence electron configuration.  A single crystal of SiC may be electrically conductive, but how the individual crystals are bonded to each other has to be taken into consideration for a ceramic.  The result was an open circuit on my ohmmeter at 1 cm.  It's pretty safe to say you will have no issues with electrocution using a nitride bonded SiC shelf in an electric home oven in proper working order.

- red.november

Offline Pizza_Not_War

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Re: Silicon Carbide Baking Surface
« Reply #32 on: August 29, 2008, 02:21:06 PM »
Dimensions: 16" x 16" x 0.625"
Weight: 6.464 kg
Price: $127.25
http://www.seattlepotterysupply.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=31257&Category_Code=HASCS


Currently with shipping to the great state of Oregon $107.00 - I will be fast baking indoor pizza next week.

PNW

Offline November

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Re: Silicon Carbide Baking Surface
« Reply #33 on: August 29, 2008, 02:52:50 PM »
I will be fast baking indoor pizza next week.

PNW,

What is your oven's rated wattage for baking and broiling?

- red.november


Offline Pizza_Not_War

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Re: Silicon Carbide Baking Surface
« Reply #34 on: August 29, 2008, 03:25:49 PM »
PNW,

What is your oven's rated wattage for baking and broiling?

- red.november
Maytag model CWE9000BCB circa 1997. Also have a Maytag gas oven as well... the label on the oven says 120/240V 5.8 kw


PNW

Offline Pizza_Not_War

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Re: Silicon Carbide Baking Surface
« Reply #35 on: September 05, 2008, 12:13:06 PM »
My first impressions of the SIC - I first tested the shelf by putting on top of the 2stone pizza grill. I removed the top aluminum cover and internal top stone of the 2stone and put the 16x16 SIC over the grill. It just fit and I fired up the grill. Warm up time took longer with the SIC in place as I think it absorbed more heat than the usual thin stone that sits on top. The pizza's took a few seconds longer to bake than normal and I pretty much decided that for baking a few pizza's this would not be a good use for the SIC. It might work ok for a larger batch of pizza.

Second test was in the electric indoor oven. I put the SIC on the top shelf 3 7/8 inches from the broil element. This distance was considerably more than November's 2.36 inches and most likely accounts for my differing results. Quite frankly I forget to raise the SIC up higher, I will do so next test. It took approximately 25 minutes to get the SIC to 600+ degrees at that distance and the pizza baked in 2 minutes with the cheese nicely brown/burnt as my wife likes it. I like the fact that I can cook the top to order and turn the broiler off so the bottom can continue to bake.

Wife gave it a thumbs up, I prefer the 2stone crust at this point, but the 2stone does not always get me a fully cooked topping without a somewhat charred bottom crust.

The dough was my standard - flour (San Felice or Caputo), Ishcia starter, salt & water (62%).

Next time I will raise the shelf higher and I can see this being a very viable way to make a quick lunch for one/two pizza without having to endure the cold rains of winter.

PNW

Offline November

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Re: Silicon Carbide Baking Surface
« Reply #36 on: September 05, 2008, 02:57:48 PM »
PNW,

Interesting results.  Thanks for testing it.  One thing that I'd like to point out that may not be obvious is that when a material like SiC has such high thermal conductivity, it can rapidly lose its heat to the environment, not just to the pizza.  It's a lot like copper in that it can get hot fast but it can cool down fast too, making both materials (Cu, SiC) ideal for welding tips and gas burner nozzles.  So SiC isn't the kind of surface material you want preheat, turn down the heat, walk away, and use to cook a pizza on a few minutes later, at least if you want a pizza to bake as fast as possible.  In my situation, the insulation in my oven is 1970's standard and isn't very good, so the heat that the SiC loses during broil primarily escapes to the cabinet above my wall oven.  Your oven may be much better insulated which is why your top is cooking faster than your bottom when you use broil.  That and the fact you probably have a better broiler than I do.

Overall, given your setup, your outcome was probably as good as can be expected.  Based on my calculations using your SiC distance and preheat time, your broiler/insulation is about 1.6 times more efficient than mine.  If you raise it any higher, you will most certainly have to turn the broiler off before the pizza is finished.  You could probably pull off a faster bake time than I have ever gotten.

- red.november

Offline heehee61

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Re: Silicon Carbide Baking Surface
« Reply #37 on: September 16, 2008, 07:17:04 PM »
Just curious how SiC would affect bread baking given that it cooks so quickly

Offline November

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Re: Silicon Carbide Baking Surface
« Reply #38 on: September 17, 2008, 03:08:09 PM »
Just curious how SiC would affect bread baking given that it cooks so quickly

I have used it several times to bake flat breads such as naan and roti, but I don't think it would be well suited for a large loaf that requires a slow bake.

Offline Pizza_Not_War

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Re: Silicon Carbide Baking Surface
« Reply #39 on: October 23, 2008, 12:09:43 PM »
Finally got around to doing another SIC bake since the cold is starting to settle in outdoors. I move the shelf to a little less than 2.5 inches from the element and was surprised that the warm up time was not really much faster than previous tests. The pizzas bake fast and the top does brown / singe nicely, however my dough lacks the same qualities it gets from the 2stone grill oven.

Not sure how efficient the broil element is. As I recall from the old days the stove top electric elements would lose efficiency over time and when I would replace one things would cook faster. I wonder if the truly lose efficiency of is it a figment of my imagination?

If I continue to use the SIC I feel I need to formulate a different dough, most likely giving up on the 00 flours. Next indoor bake will be going back to the Fibrament below and cast iron pan 1 shelf up for comparison purposes.

PNW

Offline BurntEdges

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Re: Silicon Carbide Baking Surface
« Reply #40 on: January 15, 2009, 01:36:39 PM »
November,

Very nice work here with the SiC baking surface.  As a matter of fact it has prompted me to order a nitride bonded SiC shelf which is due to arrive today.

I want ask you about how you load your unbaked pizza onto the SiC.  With only 6cm of clearance between your SiC and broiler element, how do you do it?  Do you just shoot it into that narrow opening with a peel?  Or, do you roll out the shelf from under the broiler element?  If so, does that compromise the bake in light of the SiC's high rate of thermal conductivity?

I realize that this thread appears to contain your most current information/experiences with the SiC material, but in an earlier thread dated October 2007 http://www.pizzamaking.com/forum/index.php/topic,5645.20.html , you replied:

"I will add that I would suggest trying to find silicon carbide that isn't nitride bonded.  It's a very strong material, but the nitride bonding decreases the density." 

The shelf that I purchased is nitride bonded, as is the one that you discuss in this current thread.  Maybe I misunderstood the context of the Oct. '07 thread, but it appears that you have changed your opinion on the benefits of a nitride bonded shelf.  What insight caused you to favor the nitride bonded version?

Also, I ran into a bit of a discrepancy with Seattle Pottery concerning the SiC shelf.  I'm certainly not asking you to speak on behalf of them, but want to relay what happened.  Their item #31257 (for which you provide an accurate link) is indeed a 16 X 16 X 5/8" SiC shelf.  But according to them, this unit is not nitride bonded, it is their "regular" SiC shelf.  She added that they do carry a 16 X 16 nitride bonded SiC shelf, but that it is only .394" thick.  She was not aware of them carrying a nitride bonded shelf, in that size, that was thicker.  I just want to be sure that I'm cooking on the same material that you have been using.  Since this material conducts heat so well, I opted to get the thinner (.394) nitride version over the thicker (.625) non-nitride SiC shelf.  Do you feel that will impact my baking performance or cause the baking surface to be more fragile?  Any problems with this shelf cracking when you place the raw pizza on it?  Did you do anything to prep the SiC shelf for its first use (cleaning or moderate temps)?  Sorry for peppering you with so many questions.    Thanks.

Offline November

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Re: Silicon Carbide Baking Surface
« Reply #41 on: January 15, 2009, 02:57:44 PM »
I want ask you about how you load your unbaked pizza onto the SiC.  With only 6cm of clearance between your SiC and broiler element, how do you do it?  Do you just shoot it into that narrow opening with a peel?  Or, do you roll out the shelf from under the broiler element?

I've done both, and both ways have turned out fine.

I realize that this thread appears to contain your most current information/experiences with the SiC material, but in an earlier thread dated October 2007 http://www.pizzamaking.com/forum/index.php/topic,5645.20.html , you replied:

"I will add that I would suggest trying to find silicon carbide that isn't nitride bonded.  It's a very strong material, but the nitride bonding decreases the density." 

The shelf that I purchased is nitride bonded, as is the one that you discuss in this current thread.  Maybe I misunderstood the context of the Oct. '07 thread, but it appears that you have changed your opinion on the benefits of a nitride bonded shelf.  What insight caused you to favor the nitride bonded version?

Nothing has changed, and it wasn't an opinion.  The nitride bonding decreases the density.  I purchased what I was told was a nitride bonded SiC shelf because the price was right and the thickness was suitable.  If it had been a 0.5" shelf, I wouldn't have purchased it because a nitride bonded shelf with those dimensions would have weighed too little.  I wanted at least as much mass as I had with my previous shelf.

Also, I ran into a bit of a discrepancy with Seattle Pottery concerning the SiC shelf.  I'm certainly not asking you to speak on behalf of them, but want to relay what happened.  Their item #31257 (for which you provide an accurate link) is indeed a 16 X 16 X 5/8" SiC shelf.  But according to them, this unit is not nitride bonded, it is their "regular" SiC shelf.

The product I was told I would get, and the product I received, has the properties of a nitride bonded SiC shelf.  What they're offering could in no way be sintered, or else they have a horrible supplier of sintered SiC shelves.  The density of sintered SiC is above 3.1 g/cm3, while the density of what they're selling is bellow 2.7 g/cm3.  I would also find it rare to get anything but nitride bonded SiC shelves at a pottery (kiln) supply store.  "Regular" in their case probably means it's not specified as a nitride bonded shelf as some name brand manufactures do, so they probably don't even know what kind of SiC it is.  If it isn't nitride bonded, it's curious that it pretends to be.


She added that they do carry a 16 X 16 nitride bonded SiC shelf, but that it is only .394" thick.  She was not aware of them carrying a nitride bonded shelf, in that size, that was thicker.  I just want to be sure that I'm cooking on the same material that you have been using.  Since this material conducts heat so well, I opted to get the thinner (.394) nitride version over the thicker (.625) non-nitride SiC shelf.

If they're claiming that the "regular" shelf is not nitride bonded, getting a thinner nitride bonded shelf is even worse.

Do you feel that will impact my baking performance or cause the baking surface to be more fragile? 

You don't have to worry about fragility, just the fact you are dealing with a lot less mass.  The baking performance will be vastly different.

Any problems with this shelf cracking when you place the raw pizza on it?

No.

Did you do anything to prep the SiC shelf for its first use (cleaning or moderate temps)?

I brushed all the surfaces down with a wire brush, then cleaned away the particle debris with damp paper towels.

- red.november
« Last Edit: January 15, 2009, 02:59:44 PM by November »


Offline BurntEdges

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Re: Silicon Carbide Baking Surface
« Reply #42 on: January 15, 2009, 03:06:12 PM »
November,

I appreciate the prompt reply.  I should have had this dialog with you before I bought the shelf!

In what way can I expect the baking results to be different with the thinner shelf?

In your dough recipes, what hydration % have you found to be best on this cooking surface?  Thanks again.

Offline November

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Re: Silicon Carbide Baking Surface
« Reply #43 on: January 15, 2009, 03:30:15 PM »
In what way can I expect the baking results to be different with the thinner shelf?

You won't be able to bake as large or as many consecutive pizzas.  I don't know the exact properties of the shelf you ordered.  At 63% the thickness, and possibly less dense still, it's conceivable that it won't even be suitable for baking any pizza.  Did they mentioned how much it weighed?

In your dough recipes, what hydration % have you found to be best on this cooking surface?  Thanks again.

I have already mentioned this before, but I don't bake pizzas directly on the surface that much because I like to use pans out of convenience.  I got the shelf to show proof of concept.  I don't know of a "best" hydration for the SiC surface as it would depend on what kind of crumb one is trying to achieve.  I usually start at 61.8% and go up from there depending on how long I let it ferment or what kind of flour(s) I'm using.  Lately I have been using the shelf in combination with American style pan pizzas (kind of like Pizza Hut's).  I keep the shelf at the second position, or about 11.5 cm from the top element, and place the 14" x 1.5" pan on top of the shelf.  I bake at 500F for 6-7 minutes.

I do bake a form of quesadilla directly on the shelf using the broil setting all the time.

- red.november

Offline BurntEdges

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Re: Silicon Carbide Baking Surface
« Reply #44 on: January 15, 2009, 03:52:23 PM »
I did not discuss the weight of the shelf.  The checkout calculator shows the item weight as 8.8 lbs.  I thought that might be the gross weight for shipping purposes, but when I ran tracking info on it, FedEx listed the package weight at 10.5 pounds.  They're usually pretty accurate.  So without having an opportunity to weigh it myself, I would say that it's around 8 pounds.

Why may this shelf possibly be unsuitable for pizza?  Won't the thinner shelf re-heat quickly for consecutive bakes?

Can I improve its performance by placing it on top of a cordierite shelf?  Or is that defeating the whole purpose of the SiC material?  I guess the worst case is I return it & eat the shipping charges. -

BurntEdges

Offline November

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Re: Silicon Carbide Baking Surface
« Reply #45 on: January 15, 2009, 04:00:49 PM »
I did not discuss the weight of the shelf.  The checkout calculator shows the item weight as 8.8 lbs.  I thought that might be the gross weight for shipping purposes, but when I ran tracking info on it, FedEx listed the package weight at 10.5 pounds.  They're usually pretty accurate.  So without having an opportunity to weigh it myself, I would say that it's around 8 pounds.

At 8.8 pounds, that's just less than the density of what I have.

Why may this shelf possibly be unsuitable for pizza?  Won't the thinner shelf re-heat quickly for consecutive bakes?

If it can't store enough thermal energy to bake a single pizza, then it would be unsuitable for pizza.  You won't know that for sure until you try it, or if I had more exact thermal property numbers I could calculate it.  The ideal situation is to avoid reheating the surface at all.  A good stone/surface should be able to handle a couple pizzas back-to-back.

Can I improve its performance by placing it on top of a cordierite shelf?  Or is that defeating the whole purpose of the SiC material?

You can improve the heat capacity by a great deal, but it won't improve overall performance by much.

Offline Matthew

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Re: Silicon Carbide Baking Surface
« Reply #46 on: January 16, 2009, 08:02:34 AM »
RN,

Looks to me like if used properly can yield pretty amazing results with this product.  Would it be suitable for use in a gas fired oven?  The obvious reason is that if I used the broiler at such close proximity to the top of the pizza that it would burn it in no time.  I am wondering if the same results can be achieved by placing the surface in the middle of the oven.  As far as heat up goes, Traditionally you would place your stone in the oven cranked as high as you can get it, wait for the stone to heat up & bake your pizza & then possibly place under a broiler for a few seconds.  You mention that you heat your surface by using the broiler only & leave the door slightly open so that the  broiler remains on. Will the heat that is escaping from the open door have any effect on the temperature of the Carbide Surface?  Lastly, can you cook on the surface without using a pan or will it burn the bottom before properly cooking the top?

Matthew

Offline November

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Re: Silicon Carbide Baking Surface
« Reply #47 on: January 16, 2009, 10:20:23 AM »
Would it be suitable for use in a gas fired oven?

It depends on what you mean by suitable.  With some adjustments you can use it like any other stone if you want, but the reason I started this thread was to talk about fast baking with it because that's the advantage it holds over other stones.

The obvious reason is that if I used the broiler at such close proximity to the top of the pizza that it would burn it in no time.

That's the point, or at least baking a pizza quickly is.  All things bake before they burn.  The goal is to pull the pizza out before it burns.  If you are reluctant to bake your pizza fast, this is probably not the best investment for you.

I am wondering if the same results can be achieved by placing the surface in the middle of the oven.

No.  As I alluded to in the first post, the results will not be the same.

Will the heat that is escaping from the open door have any effect on the temperature of the Carbide Surface?

Yes, but the effect depends on the oven.  I said that I kept the door barely open so that the broiler would stay on.  That is what typically happens with an electric oven.  That is not necessarily what what happens with every oven though, especially considering how gas ovens operate.

Lastly, can you cook on the surface without using a pan or will it burn the bottom before properly cooking the top?

I've never posted a picture of a pizza baked any other way than directly on the surface in this thread.  Looking just a few posts up you will see I addressed BurntEdges' question about which method(s) I have used to load the surface.

- red.november
« Last Edit: January 16, 2009, 10:22:57 AM by November »

Offline Matthew

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Re: Silicon Carbide Baking Surface
« Reply #48 on: January 16, 2009, 06:30:48 PM »
RN,
Thanks for the response, definitely makes sense.  I have sourced one locally, the thickness is 1/2" as oppose to 5/8".  Will it make a significant difference in the thermal energy?  The link is  http://www.pshcanada.com/kiln-furn.htm.  Would you happen to know the difference between nitride bonded & oxide bonded?  Which is better; or does it really matter? 

As you can see, they also sell a shelf that's Cordierite-mullite up to 1" thick.  I know that there have been quite a few past threads about cordierite, but I'm not sure what mullite is?  Would it work well as a pizza stone?  How would it compare vs. Silicon Carbide? ??? 

Matthew
« Last Edit: January 16, 2009, 06:34:50 PM by Matthew »

Offline November

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Re: Silicon Carbide Baking Surface
« Reply #49 on: January 17, 2009, 10:58:39 AM »
I have sourced one locally, the thickness is 1/2" as oppose to 5/8".  Will it make a significant difference in the thermal energy?

1/2" means 20% less heat capacity than 5/8".  It's only significant if you are baking two or more pizzas back-to-back.

The link is  http://www.pshcanada.com/kiln-furn.htm.  Would you happen to know the difference between nitride bonded & oxide bonded?  Which is better; or does it really matter? 

They show you that there's not much difference in density.  The oxide bonded is not as thermally conductive as nitride bonded however, but still greater than most pizza stones.

As you can see, they also sell a shelf that's Cordierite-mullite up to 1" thick.  I know that there have been quite a few past threads about cordierite, but I'm not sure what mullite is?  Would it work well as a pizza stone?  How would it compare vs. Silicon Carbide? ??? 

Cordierite/mullite is often just sold under the label of cordierite.  I've found that asking the supplier about whether they sell pure cordierite or a cordierite/mullite combination is usually fruitless.  If they provide a data sheet, fine.  Otherwise there's not much use in worrying about it.  If you're not sure what mullite is, you can always read an article on it (http://en.wikipedia.org/wiki/Mullite).

Generically, SiC (nitride bonded in this case) has a thermal conductivity approximately 30 times greater than that of a typical baking stone.

The "30" I stated above is a rounded number based on comparing nitride bonded SiC to a generous average between Fibrament and cordierite.  Even the oxide bonded SiC you pointed out is about 20 times greater than Fibrament.  Typical baking stones and SiC aren't in the same category, so I wouldn't try comparing them to SiC more than that.

- red.november
« Last Edit: January 17, 2009, 11:17:32 AM by November »