How can you tell the year of the DS1 I just picked up?

[mnolan]

Greetings! I'm a new member and owner of a DS1 that is quite old. The hull serial number is 21085 and the class number is 3857. The sail number is 1 (which I'm sure is just a joke of it's age). Any info would be quite helpful and most appreciated while I restore it to some semblance of it's former glory. Thanks!

[GreenLake]

Check this site for the hull number index. It might give you a year.
The "class number" is what should have been on your sail.

[ctenidae]

You can use the info HERE to try to date your DS1 based on features. You should also plug your data in so that it helps complete the records. Based on 21085 and 3857, probably a 1970 model.