John we think the lot 5 came out in 1922 or 23. The 1922 patent number covers the end door hinge used on the TL pattern makers lathe. Think you have the lowest Lot 5 serial number. We need to see a picture of it to tell if it’s one of the first 100 or so prototype Lot 5 lathes. Dennis

?Hello to the group. I just aquired a dalton six lot 5 number 23. I would like to know? what year it was made as the last patent date on the tag is mar 26 1918. According to any pictures i can find seems to indicate that this lathe would have been made around 1922. Looking for some help.? Also would any of you know the thread size and pitch of the head stock spindle. Thanks for any help Jon.