Sometimes my brain just trips over itself when trying to solve a problem.
I happened to have a lift and turn sink drain from the granite vessel sink installation that I realized had a long enough stem to use for the tub. So I cancelled the expensive drain order and thought I would try to use the sink drain.
When I put it in the tub, I thought it would work, the threads are long enough, but I got distracted by looking at my original plan for the drain, which was to use a 1 1/2″ pvc female connector.
The standard PVC 1 1/2″ pipe was way too “fat” for the opening so I used the dremel tool to shave off the outer edge of the threaded part of the pipe leaving just enough to keep the threads and still be able to push it up through the drain to meet the shorter but nicer Moen lift and turn drain piece. I was able to get the pipe thin enough and pushed up into the drain so that the Moen drain piece met it and could tighten inside the tub.
Then I realized that I wanted the drain to be able to use the overflow so I unscrewed the drain and cut two slits into it to allow water to enter the drain to and from the built in overflow. But of course NOW I REALIZE why I decided this original plan would not work. I can’t seal the overflow from below the drain! There are no threads on the pipe that comes out of the bottom, just a glued pipe hub. Now water in the overflow will leak past the pipe that is fitting into the drain opening from below and then all over the floor. Not a very good idea for a drain assembly.
This might have worked without the overflow cut, but now I have two slits in the nice Moen drain. While taking photos of this process I saw that I probably could have used silicone caulk to seal the PVC where it meets the lower tub surface.
But another problem is that there is too much pipe under the drain. Gluing the female threaded pipe to another male threaded pipe and then screwing that into the drain elbow will not give me enough room under the tub to manage the 1/8″ per foot slope to the floor drain. I chipped out a bit more concrete and cut the drain down so that the elbow sits right on the concrete floor.
If I could just find a narrow pipe bushing with coarse threads inside and another set of outside coarse threads to extend the pipe, I could connect the Moen drain with a gasket and threaded nut that would keep it from leaking. But there is no such pipe as far as I know.
I found drain bushings from Watco and the least expensive version changes the pipe thread type from fine–16 threads per inch to coarse–11.5 threads per inch. But I can’t find the specifications for the length of these bushings and I assume it is meant to screw completely onto the 1.5 inch long Watco drain threads. So this is not the answer either.
So what about that sink drain? It is long enough at 2.5″ but I would again have to cut the overflow slits. The slits would work for this drain because I can use a rubber and washer below that comes with it. But it connects to narrower pipe than the tub elbow, only 1 1/4″ and I would have to use sink drain tubing to drain the tub which is probably not to code.
I finally found a possible solution on ebay. It is an American Standard lift and turn tub drain that had a quick response from the vendor to my question about size.
The total height is 3″, the widest point is 2 3/4″ and the pipe connection is 1 1/2″.
I ordered it for $19.80 with free shipping. I could NOT find this drain on the American Standard web site. But once I knew what the drain looked like, I did find it as part number 791474-0020A available from Home Depot by mail order for $26.77. The photo above does not show an overflow, but the part at Home Depot does. The specifications state it is 3.5″ long by 2″ wide x 2″ deep. Which apparently is close enough for some buyers.
In other research I found that American Standard’s normal thread type is coarse. So this drain should screw directly into the tub drain elbow, which I found is called a “tub shoe”.
I was able to get the pipe OUT of the bottom of the tub after whacking it in there with a 5 lb. hammer and tightening the drain to it to pull it into the socket more. I just used a screwdriver on the ledge of the pipe and whacked it with the 5 lb. hammer and it fell out. Next the new drain will be shipped and I’ll get to see if it will work.
UPDATE: The American Standard drain worked. I had to add an extra foam bushing and rubber seal to tighten the tub shoe below the indentation for the drain under the tub so that the drain pipe would fit into the shoe.