1 1/2 inch NPT thread chasing die

I needed to clean up a very dirty/corroded 1 ½ inch NPT thread where a dishwasher had been rigged to an ABS trap adapter many years ago and had leaked for a while too. I didn't have a real 1 ½ inch pipe threading die (and didn't want to buy one!), so I drew this up and printed it. It worked fairly well for cleaning the threads.  The pic of the die is from after I used it to clean the threads--held up pretty well. I also included a pic of the trap adapter, but I had already assembled a new PVC adapter to it by the time I thought to take a picture.