Kitchen Benchtop Joining

[mrstevo]

Hi, I'm building myself a new kitchen, done all the cabinets and got them sitting in place ready for the benchtop to go on.
Now, I have to make a template benchtop out of 18mm mdf with sink cutout etc to go into the granite place for them to be able to make the granite benchtop fit to my template, and then the template gets fixed back to my cabinets and the granite will then fit on top.

My question is, what is the best way to butt join the 18mm mdf to be strong and rigid. I have some of the threaded benchtop connectors http://elraco.com.au/product_info.php?products_id=2604
but am concerned that their holes would actually be cut right thru the 18mm thickness and weaken the joining method.
My other idea would be to glue and screw a piece under each side of the joins to thicken it to 36mm, and then the connectors would be recessed only part way thru the actual top sheet.

Its a U Shaped kitchen so i have 2 joins to do, i'm figuring that to join them on corners would be best, greater length to add dowells to etc.

Hoping to hear what anyone else has to add and any advice is appreciated.
Cheers

[Bleedin Thumb]

Hi Mr Stevo,
I may be missing something in the translation but...
If you are just using the MDF as a template couldnt you just screw and glue battens ON TOP of the MDF it shouldn't be in the way when they measure the stone. Also I would have thought that the stone suppliers would have prefered the templates unjoined as it would be easier to man handle. Just mark A:A B etc on joins .. just a thought ask them.

[mrstevo]

Sorry Bleedin Thumb, I'll elaborate, the granite people will use the template to cut and size the stone, and then the template will be fixed to the benchtop and the granite will fit over the template and be fixed to it, so the template i have to make will actually be sitting under the granite once installed to help support it. The front edge of the granite will be 40mm to come over the front edge and cover the mdf.

Does this make sense, not sure if this is a usual practice but sounds a good idea to have a stable flat surface for the granite to sit on.

[Bleedin Thumb]

Hi MrSteve, yep that makes it clearer, there is a thread back a bit about the pros & cons of having backing to granite tops. I beleive you can do without but I would be happier if I used them I think.
Couple of thoughts,

Still dont know if you need them joined or not when used as templates.
Also hope your using HMR MDF.
Dont think 18mm MDF is strong enough for benchtop connectors.
Not sure if you need a strong joint in the MDF .. its the granite joint thats important.
If you look under the overhanging granite lip wont you see the MDF exposed at the face of the carcass and have you allowed for the extra 18mm with your door heights?
Sorry if I'm stating the bleedin obvious
Good luck

[arms]

hi ,well i have been associated with literally hundreds of granite tops and all we have ever ,and i mean ever done is make templates from 3mm mdf exactly to the shape required ,marked all exposed edges marked joins ,then the stonies come along and check the templates in situ make any markings that mean anything to them ,take the templates away, lay them on the stone ,cut as required ,come back to the house with the stone suppling timber strips the same thickness as the stone (because all stone is not guaranteed to be a certain thickness )nail the strips as support for the top ,finish the job ,smile as best they can ,put their hand out with an invoice ,i check the job and if i am satisfied pay them ,it seems to me that you are going to a lot of work and expense to do the job that the stonies have probably quoted for anyway

[renomart]

What Arms said.

My stonemasons come out to measure for themselves.

[Honorary Bloke]

Listen to arms and Renomart. Here's the conversation:

You: "Gentlemen, I believe the granite top is not spot on."

Them: "It's YOUR template, innt it?"

You: "Yes, but . . .. "

Them: "You stuffed it, not us."

You and them: #^&*@&%^#%$#*

Let them do the measure.

[mrstevo]

quote=Bleedin Thumb
Also hope your using HMR MDF.
Yes

Dont think 18mm MDF is strong enough for benchtop connectors.
Me either, thats why i was thinking of glueing and screwing another strip at the join to make it 36mm

Not sure if you need a strong joint in the MDF .. its the granite joint thats important.
I'd still prefer a solid base to it, no movement etc

If you look under the overhanging granite lip wont you see the MDF exposed at the face of the carcass
I figure that if my 18mm template edge is flush with the carcass, and the granite being 40mm thick at the edge, i.e, 20mm over the top of the carcass's and 20mm as the edge is fitted up to it, the granite would be lower and cover the edge of the MDF.

and have you allowed for the extra 18mm with your door heights?
Yes, but i havent made my doors yet, still sourcing some Jarrah, but being in Tas and not being able to visuall see it, i'm dubious about ordering it sight unseen.

Sorry if I'm stating the bleedin obvious
No probs, gald you are thorough.


Arms, Renomart and Bob, Thanks for letting me know that, It looks like i'll have to give them a call and clarify things further with them.

Cheers

[blanco]

Hi all
interested in what you all have to say as I am currently looking at putting in a granite top, is that usual for the template to be used under the top, Iwas told by the granite suppliers to cut out and give them a template, I would feel much better if they would do this and why cant I just give them the old benchtop?

I calculated my granite top to cost 1700, their quote is 3700 does this sound about right, 2000 for cutting and fitting?

Would I be safe taking off the current top laying on the MDF and scribing round that for a template?

Rgrds
Blanco

[journeyman Mick]

Get them to make their own templates, it's normal industry practice. That way there can be no arguements if things go wrong.

Mick

[evc722]

I quoted half dozen for granite and man-made stone benchtop, ppl usually asked for a template when they are sending out order to third-party company for the job. simply ask them to come a measure, it will cost ~$250.

however I just did a 20mm ceasearstone bench, so worry about if the bench sitting right on top of cabinet without MDF underneath, it will break after certain period of time. Can someone suggest ??????