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doctor demo
07-11-2009, 01:53 AM
Hi all, I had a glass cook top untill swmbo dropped the salt shaker:o ,
A new cook top is out of the question...$900.00 , the replacement glass is $250 plus tax and shipping:eek: .

I have a piece of aluminum plate that I could cut out , but ....can I paint or powdercoat and have it hold up to the heat? Or maybe anodize?

I am under pressure from swmbo to get the kitchen back to normal, oh and did I mention that I'm cheap?

Steve

darryl
07-11-2009, 02:36 AM
Hmm, offhand I'd say that aluminum has a thermal expansion ratio that's too high for that. It would probably twist and warp and buckle.

doctor demo
07-11-2009, 03:24 AM
Hmm, offhand I'd say that aluminum has a thermal expansion ratio that's too high for that. It would probably twist and warp and buckle.
That was My initial thoughts also, but it is below the burners and while cooking ya used to be able to wipe up any spills on the glass with a paper towel. I wish I woulda done some surface temp testing when there was still a surface to test.

Steve

Evan
07-11-2009, 08:28 AM
Thermal expansion is the kicker. The original top was made from borosilicate glass which has an almost nil coefficient of expansion. Anything made of metal will buckle to a serious degree unless the heat is evenly distributed across the cook top.

You say "below the burners". That doesn't sound like a cook top to me. Please explain further.

Bob Ford
07-11-2009, 10:03 AM
You might check Torker's thread, $900 sounds cheap to me.:)

Bob

MickeyD
07-11-2009, 10:06 AM
I don't think that it would warp, just that the whole top would heat up at the same time instead of just the "burner" areas. I doubt that you would really be able to cook on it like that and after you and especially your wife burned herself and accidently melted things on the non-cooking parts of the top (like the knobs), you would quickly go and buy the correct top.

Paul Alciatore
07-11-2009, 10:19 AM
DO NOT USE ALUMINUM or ANY other metal. The expansion thing is a problem you may never see as your kitchen may burn down long before you get there. Aluminum is an excellent heat conductor and the entire top will rapidly heat up, ALL THE WAY TO THE EDGES. Worst case, this could set the counter top on fire. It will at least scorch it and you will have to replace that also.

Get the $250 part and relish your $avings.

Fasttrack
07-11-2009, 10:33 AM
Sounds like a good oppurtunity to purchase a new granite surface plate ... :D

doctor demo
07-11-2009, 02:15 PM
Thermal expansion is the kicker. The original top was made from borosilicate glass which has an almost nil coefficient of expansion. Anything made of metal will buckle to a serious degree unless the heat is evenly distributed across the cook top.

You say "below the burners". That doesn't sound like a cook top to me. Please explain further.
I've been trying to add a link to the "cook top" in question but the site loads so slow that when I finaly get to the item .... "the program is not responding" so I will have to describe.

Picture a glass sheet 26''X36" with 5 holes approx 7" in diameter and 5 holes 2.5" in dia. The small holes are where the knobs are. The large holes are where a square enamel coated metal pan with a 3/4'' deep round dimple sits with the burner and igniter, on top of the pan is a cast iron grate for pots and pans to sit.

This top is also available in stainless steel , but swmbo does not like ss.
The unit that this replaced was an old G.E. electric , 4 element top that was enamal coated sheet metal.

The reason I thought I might get by with the aluminum is it is the same thickness as the glass and would be strong enough to support everything with out having to add ribs underneath or be of a stamped design like the stainless top is.

I'm off to the scratch and dent dept of sears for a look around and maybe one of the box stores as well.

I don't think that heat/fire issues with the counter top is an issue as it is ceramic tile over a 1''thick grout bed, but I don't want the top bending and pitching the pots off the burners.

If I were to go the stainless replacement route, I would have to finish it with something to get it white to match the rest of the kitchen.

Thanks
Steve

doctor demo
07-11-2009, 02:23 PM
Sounds like a good oppurtunity to purchase a new granite surface plate ... :D
Believe it or not I considered using a piece of granite :cool: (not a surface plate) but I did not want the adventure. I can and have in the past , cut and core drilled granite.


Steve

Evan
07-11-2009, 03:29 PM
OK, makes more sense now. Aluminum still isn't a good choice because of the conductivity. SS is a lousy heat conductor which is a good thing in this application. Aluminum will become hot all over and will be very hard to clean unless anodized. Aluminum is also strongly attacked by caustic stove cleaners. Paint isn't going to work in this application either.

Your easy choices really come down to an OEM replacement or fabricating something from SS.

There is however another possibility that might work and won't cost nearly as much as the OEM top. Use ordinary sheet steel of sufficient gauge to be stiff enough. Seal it with a good quality automotive primer and bake that on at 250 degrees until no trace of solvent smell remains.

Then cover that with ceramic tiles of SWMBO's choice bedded in grout on a layer of fiberglass mat and sealed with several coats of sodium silicate concrete and grout sealer soaked into the completely dry grout. Don't use any other type of sealer for this application.

Note: Giving her a choice of tiles assures that she must be happy with the result, even if she isn't. It was her choice.

doctor demo
07-11-2009, 05:41 PM
OK, makes more sense now. Aluminum still isn't a good choice because of the conductivity. SS is a lousy heat conductor which is a good thing
Your easy choices really come down to an OEM replacement or fabricating something from SS.



.
Thanks for the help, They do make that top in ss but I can't tell if it is Exactly the same . I do not want to order another glass top after this broke so easily. It was not a huge heavy item thrown at the top,it was small and light dropped from about 10'' from the surface.

If I make or order a ss top , can that be anodized to a color of choice that will hold up ? Swmbo HATES stainless steel.

Steve