I have 2 problems with installing the 1 1/2" overflow drain on a mini sink I am trying to install. 1. the sink sits on top of the cabinet, but I have installed a granite top to it, so the drain body is too short to allow the attachment of the tail piece, here is a pic of the sink/granite top
and the drain
[postimg.cc],

the second problem, the bottom of the drain throat on the sink is not level with the outer walls of the sink, it is about 3/16th of an inch above the granite top and the wedge shaped seal with the drain,is too tall and hard , it does not allow the sink to sit flat on the granite top and does not conform into the space between the drain body and walls of hole drilled into the granite or throat of sink. here is a pic of the sink bottom and the seal on the drain

[postimg.cc]
[postimg.cc].

I have found a drain body extension on plumbingsupply.com, but it doesn't say what the diameter it is.

Does anyone know of one that will fit 1 1/2" drain body?



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none of your pictures can be opened.
try again so we can answer accurately and not just guess.

well, I changed to the url address and the only one that loads in the post is the pic of the sink/granite top, I think if you right click the little icon for the rest and select the open in a new tab, it then will show.

The drain assembly isn't suppose to mount to the granite, just the sink. Cut/drill the hole in the countertop bigger That's an unusual sink/countertop installation.

the area is very small, 73"x37", across from it is a toilet (to make a powder room). and a regular cabinet was too big to allow the door to open, this little sink can also be mounted to the wall, but we needed a cabinet (10x30" for small area for storage also, so this fit the space well, just have the problem with the sink drain. The thickness of the countertop was increased because of having to raise the granite edge up above the cabinet top, as the door opens immediately below the cabinet top and the granite edge hung down below it, so had to have 1/2" board on the top of the cabinet top. so guess I have to find a drill bit to enlarge the granite opening enough to allow the nut to tighten up on the sink

So, there isn't an extension that will screw into the inner throat of the drain body?

[i.postimg.cc] [i.postimg.cc]

Your basin is incompatible with the granite top

UNLESS

you bore ( or have bored by a granite top company) a LARGE hole through the granite where the basin drain is located.


Probably cheaper to get a new compatible cabinet or redesign what is now an abortion.


( by large i mean 4" )

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638



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[www.amazon.com]

also, one of these with pipe dope on the male threads and screwed into the bottom of the drain will make life easy.

[www.homedepot.com]

I think the bigger issue is that unless that basin has an overflow, and I very much doubt it, that is the wrong drain fitting for it.

No, but IF the sink does not have an overflow, AND you have the correct drain fitting, it would not need ANY rubber seals below the sink as long as the flange is sealed to the sink with silicone caulking. Then the lower nut would clamp the sink to the deck/countertop.

It does have an overflow, main reason I bought it, to avoid any problems with water damage

The problem with your suggestion and why I need a gasket between the sink and the granite top is because the sink bottom is not even with the outer sink wall as you can see in the second photo link above, (I can't seem to provide the correct format to put it here, it shows a level placed across the bottom of the sink over the bottom of the sink drain throat) it is a difference of about 3/16th. The bottom rim of the sink throat is quit broad, do you think a good layer of plumbers putty would close and seal the gap safely and last a long time? and I was thinking that if I made sure to push some up between the drain body and the sink throat to the bottom of the overflow, it would help prevent water standing in that space between the drain body and the sink throat wall.



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the drain assembly 'clamps' to the sink itself NOT, repeat NOT, the granite


you must have a clearance hole in the counter top large enough to allow same


the drain you have IS the proper drain for the sink



you MUST have a 4" (or larger) hole completely through the entire cabinet top and granite to make this work



you will 'putty' around the edge of the sink ONLY to avoid getting water trapped under the sink, but, said putty has NOTHING to do with the drain itself

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

In that case, you have NO OPTION except to "clamp' the drain into the sink and modify the holes in the countertop to accept them.

that is EXACTLY what i have been saying

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

You mount the drain assembly on the sink BEFORE you drop it onto the countertop.

Well, thought I had found an extension, but no, So, gave up, many thanks to all your suggestions, will be making granite top opening bigger and attaching drain body directly to the sink, wish me luck on drilling the opening bigger



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you had best make a template from 1" plywood with the desired hole size drilled and clamp same to granite BEFORE starting the diamond hole saw

OR

hire a pro

OR

get a different basin

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638



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Update, finally got it taken care of, used a diamond finger bit, 10 mm. only needed to put a 45* angle and widen the upper diameter of the granite about 1/2" to allow the drain body nut attached to the sink, to fit in and then the sink sat completely flat on the granite. [www.amazon.com] Thank you all for your suggestions.



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