Looking at the headstock drain plug(s) on the HL460 lathe....they are a straight cut thread and I measure the OD at .818" and 14TPI. This appears to be a 1/2" BSPP thread....so my question is....is it reasonable that a Japanese/Korean lathe would use BSPP threads? The closest metric thread is M21 x 1.50 but that is not as close a match as the BSPP. Thanks.