Hello,

Hi Rebel,

Hey E stone fabbers...please help rebel out! While you are waiting for them to get back to you, I am Lenny. I am awake now because I am working in China. Its lunch time here!

I am not a fabricator, but I have worked in numerous E stones factories that manufacture the material. and am working with 1 e-stone factory over here now!

Yep, IMHO you have some issues there.
 
1.) 90 degree radius Cut-out- Usually when they do these cut outs in E stone they drill (machine) 4 round holes where the corners of the cook top cut out will be. This is so they can cut from hole to hole and they dont have a 90 degree angle at the corner (which is very bad) or they dont cross the cuts at the corner (which is even worse).

As far as the tightness of the cutout, as the cut-out heats up it will expand (the hole will get bigger). The problem is the cooktop heats up and gets larger also.


Long and short of it, I think you may have a potential for cracking there.

How thick is your top ( 2 cm or 3 cm?). What model of cooktop do you have? If its a gaggenau..or other aggressive cooktop, that will exacerbate the problem.

There are some other issues as well, but I am getting hungry and have to run and eat!

You may want to locate a reputable E stone fabricator  in your area to re fabricate the opening properly. 

BTW, this not typical of a good fabricator. I would look for an ISFA (International Surface Fabricator Association) member, or a fab net member. Most of the people associated with those 2 entities are very good at fabricating and installing a myriad of surfacing materials.

I hope this helps. Good luck and best wishes on your new home!

It is a 3cm slab.

I received your email, please check your email box for reply.

Since the cutout is too small you can just have the hole cut bigger and stop short of the corners and viola -- the right size and a radius in the corners.  This does depend on what the flange lets you do.

Good luck,
Than

Posted By Lenny E on 19 Sep 2011 11:30 PM

Hi Rebel,

Hey E stone fabbers...please help rebel out! While you are waiting for them to get back to you, I am Lenny. I am awake now because I am working in China. Its lunch time here!

I am not a fabricator, but I have worked in numerous E stones factories that manufacture the material. and am working with 1 e-stone factory over here now!

Yep, IMHO you have some issues there.
 
1.) 90 degree radius Cut-out- Usually when they do these cut outs in E stone they drill (machine) 4 round holes where the corners of the cook top cut out will be. This is so they can cut from hole to hole and they dont have a 90 degree angle at the corner (which is very bad) or they dont cross the cuts at the corner (which is even worse).

As far as the tightness of the cutout, as the cut-out heats up it will expand (the hole will get bigger). The problem is the cooktop heats up and gets larger also.


Long and short of it, I think you may have a potential for cracking there.

How thick is your top ( 2 cm or 3 cm?). What model of cooktop do you have? If its a gaggenau..or other aggressive cooktop, that will exacerbate the problem.

There are some other issues as well, but I am getting hungry and have to run and eat!

You may want to locate a reputable E stone fabricator  in your area to re fabricate the opening properly. 

BTW, this not typical of a good fabricator. I would look for an ISFA (International Surface Fabricator Association) member, or a fab net member. Most of the people associated with those 2 entities are very good at fabricating and installing a myriad of surfacing materials.

I hope this helps. Good luck and best wishes on your new home!

Rebel, I really think you should not be concerned. Of course the countertop installers do not do not plumbing or electrical work or install appliances. Maybe there was not good communication with whomever you bought from. Second, I'm sure the tape that your Bosch cooktop was referring to for corian, not quartz or granite. If it fits in the hole, it's ok, there are too many pieces for expansion to apply enough force, besides the only thing that could rub on the sides are the pan screws. You never mentioned the seams, edges, sink... I assume you got a job that looked good and you were ok with them leaving. Your countertop is backed by a great company. Only worry about it if something does happen, you have a super product, use it and try to abuse it. I bet you will love it in the end!! Lenny are you saying the quartz needs the same heat tape as SS? I have had 3 different companies install quartz for me over the past years. Noone has used heat tape on a cooktop or slidein stove? All were 3cm.

No Kelsey,

I wsnt saying anything about the heat tape, I was saying the hole should not be a 90 degree angle in the corner.

Rebel,
Just an observation, but it seems like you were reading the manual as intended for solid surface countertops rather than quartz.

Lenny seems to think there is cause for concern regarding the square corners and I believe everything he says (I'm still waiting for that bridge he sold me, though).

But the rules are very different for quartz than solid surface, so, as KC puts it, I doubt you have as many issues as you may think.

My 2 cents.

" Drill a hole in each corner of the cutout. It is very important that the holes have a rounded shape. This way, the breakage possibilities are reduced by a high percentage. The smaller the radius of the hole, the less breakage possibilities"

In the Silestone manual, it specifically states that there needs to be radii in the corners to prevent cracking.

This is a brand new countertop, you would think the fabrication instructions would be followed and the homeowner is correct that it should be done properly.

Andy if it has square corners, chances are it has been undercut too. The only thing the homeowner needs to do is #1 take pictures of the square corners and make notes about the cooktop size being tight. #2 send the pics and info to Silestone for reference explaining the dealer is out of business. #3 and the most important, enjoy his new top and know he purchased from a great company Btw i would never attempt to drill into the corners now. First, i believe it to be impossible now, plus if the homeowner does attempt it and it breaks, he will own a broken top with no warranty. Granite is done like that all the time without issues plus quartz is a hell of a lot stronger.

Kelsey,

I disagree. Tight corners are a place for a crack to start and with the cooktop being so tight, it is more likely to happen than if the opening was cut bigger.

Fabrication guidelines clearly state there should be radii in the corners. Why would a consumer accept a cutout with square corners? It doesn't even meet the minimum requirements.

Andy

I am with Kelsey on this one.  If the top is well supported it is unlikely to ever be a problem.

I wouldn't bother with the heat tape.

Document it, send it to Silestone and move along.  I would be interested to see what , if any, recourse you had should it ever crack, though.

 

I had an engineered stone vanity fall off the Aframe (forgot to clamp it) while we were going around a curve.  Picked it up, put it on the Aframe and went and installed it.

 

I would be surprised if they ever have a problem, unless the physically attach the cooktop to the countertop w/ screws or some such.  I would venture to say that the vast majority of Quartz and Granite cooktops cut in the field have square corners.

Hi Chris, Tom and Kelsey,

Yeah I hear you. I am not a fabricator and you guys would be on my short list to fabricate any surfacing I needed, so are most likkely correct that it won't be a problem..

However I still have to side with Andy on this. As a former fab class instructor (of the technical portion), and manufacturer,  I used to emphasize that if the fab manual says thou shalt do it this way, then thats the way thou shall do it.

BTW, that was great advice you astute fellows gave the homeowner."take a picture- contact Silestone".

Posted By Andy Graves on 22 Sep 2011 06:52 PM
Kelsey,

I disagree. Tight corners are a place for a crack to start and with the cooktop being so tight, it is more likely to happen than if the opening was cut bigger.

Fabrication guidelines clearly state there should be radii in the corners. Why would a consumer accept a cutout with square corners? It doesn't even meet the minimum requirements.

Andy

Andy, so you are telling the homeowner to go ahead and except the risk of the top breaking by trying to fix this himself ?

Read what i said Andy, if it is undercut, trying to drill it is pointless.

Trying to drill a hole in the very corner would be next to impossible . 

My guess is even a square cut piece of quartz is still a thousand times stronger than a piece of "square" cut solid surface.
 

Posted By Lenny E on 24 Sep 2011 04:37 AM
Hi Chris, Tom and Kelsey,

However I still have to side with Andy on this. As a former fab class instructor (of the technical portion), and manufacturer,  I used to emphasize that if the fab manual says thou shalt do it this way, then thats the way thou shall do it.

Oh Lenny.  Your bible says thou shalt not place seams through , sinks, cooktops, or over dishwashers, and it's done ever day! Or is it? lol

Posted By Kelsey Crisp on 24 Sep 2011 04:25 PM

Posted By Andy Graves on 22 Sep 2011 06:52 PM
Kelsey,

I disagree. Tight corners are a place for a crack to start and with the cooktop being so tight, it is more likely to happen than if the opening was cut bigger.

Fabrication guidelines clearly state there should be radii in the corners. Why would a consumer accept a cutout with square corners? It doesn't even meet the minimum requirements.

Andy

Andy, so you are telling the homeowner to go ahead and except the risk of the top breaking by trying to fix this himself ?

Read what i said Andy, if it is undercut, trying to drill it is pointless.

Trying to drill a hole in the very corner would be next to impossible . 

My guess is even a square cut piece of quartz is still a thousand times stronger than a piece of "square" cut solid surface.
 

Drill a hole in a piece of wood the same size as the boring bit you want to use in the corner. Clamp the piece of wood in the corner and use it as a template.

Norm, are you telling the homeowner to work on his own top too?

To fix what is not broken?

I am suggesting he gets holes drilled in the corners by another fabricator that know what he is doing. Doing as Norm suggested with a template will make perfect radius in the corners and will prevent it from cracking.

Hoping it won't crack seems a little dangerous to me. Countertop should last 20 years, why start off with crap?

Posted By Andy Graves on 24 Sep 2011 08:20 PM
I am suggesting he gets holes drilled in the corners by another fabricator that know what he is doing. Doing as Norm suggested with a template will make perfect radius in the corners and will prevent it from cracking.

Hoping it won't crack seems a little dangerous to me. Countertop should last 20 years, why start off with crap?

Geez, lets get back to reality here. What fabricator is going to go behind someone else and try to make square cuts round? Show me square corners that are not undercut. If it is undercut justba little, cant be fixed. What homeowner is going spend a few hundred dollars to get a third partyninvolved. i still stand behind my initial response. This top is backed by the Silestone name and the customer needs to bring them in the loop as to what one of their approved fabricators did. Norm/Andy.. Question. If the hole is drilled and the top breaks, who then does the customer turn to for warranty?

Silestone probably doesn't cover fabrication and installation. Fixing the corners is easy. A company like Back to Perfection would come in and drill the corners with a diamond bit. It is actually very simple. The flange of the cooktop will cover the radii.