Sink cut out and broken top

[Whiplash250R]

I was installing a granite job with my first undermount sink.  The tops are pre-fab slabs that are 2cm thick with a 1 ½” laminated bullnose edge.  The sink top is 26” deep by 98” long.

Problem:  I successfully cut out the initial cut for the sink and was finishing some clean up with a grinder and diamond blade getting ready for the drum sander to bring me to my marked lines.  I needed to adjust my support under the slab so I could get more clearance for my grinder and with gently just lifting the weight (I did it very gingerly) off the support the top cracked both in front of the sink all the way through the laminated edge and in the back of the sink.  But cracks are completely broke through.

Questions:

#1.  Do I repair the top or replace it.  I have informed the owners of the top and their response was don’t worry just glue it.  I had not initially even considered that.  Can that be done with very minimal detection it was cracked?  If so how would I go about doing that?  A new slab would run me around $350 plus time to re-cut the seam cut.  Would I be better attempt a fix on the old top, not in place yet and sink still needing finished.  If I do that how much time would I spend on the repair and how professional would it look?  Overall I want the job to look right for the customer but absorbing the cost would hurt.

#2  How do I prevent this from happening again.  It seems I have seen other fabricators cut the sink holes in the shop and then take them to site to install.  I did not rod the slab as I was told I only needed to do that if I was transporting the top.  I was cutting the slab on site but NOT in place but rather outside.  However as fragile as the top was I can not even imagine trying to even move it inside.  Do I need to rod all my sink tops, would that prevent this?  I was shocked it cracked through the laminated edge I was told I would only need to rod the back if I did transport it.  Would putting resin and mesh on the top help?  How is that done?  Or should I just plan on cutting the sink hole in place on the cabs?  Seems that would be tough in remodels making such a mess?  How do the other fab shops do it normally?  

[heritagegranite]

I had put in my poll vote that you should just fix it, but now that i have read it i think you should just replace the top. If it was just cracked in the front or back you could use flow grade epoxy and a fiberglass rod to repair, but i would just replace it unfortunately. Hope this was a help to you.