Plumbing sound out for the pros.?
Answers: They make a drain that will fit your sink.
It seem you are looking at a PO plug drain, or pop-up assembly, which is 1 1/4" Those drains fittings are for lavatories, bathroom sinks, vanities, etc.
That is a old sink, but the strainer you inevitability should be easy to find contained by any hardware or plumbing store.
I had to replace one that size roughly a year ago.
Standard kitchen drain openings are 3 1/2"
Your size is still available.
Yes you can acquire reducers, go to your local hardware or plumbing shop, try to rob the parts with you if you can, don't guees it.
Go to your local hardware store and ask for a reducer. Take factor of the top drain piece and part of the bottom pipe beside you. If it's PVC then it won't cost much at adjectives.
the only piece i know for sure about plumbing is that $#*^ flows down hummock and payday is on friday.
all this other stuff i enjoy learned that it is much cheaper for me to settle a plumber to do than to try to do and then settle the plumber to fix what i screwed up and then do what i tried to do contained by the first place...
Check with a restaurant supply shop, or even an automotive shop for the 2 1/2 inch strainer.
Been here done that.
Most chemical lab sinks come with the drain already contained by the sink and you connect to the threads on the bottom. I have see chemical sinks with a 3/4" drain and an 1 1/2" drain on the bottom. You should be capable of go and buy a PVC feminine adapter to screw onto the drain. However, if you have to put a strainer contained by it, they make a duplex strainer, typically used for bar sinks, that fits a 1 1/2" hole. Be sure to putty it obedient. Best of luck.
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