DIY Sails - Any cheap skates out there

[RobGranger]

Hey All: I found this site to make poly tarp or tyvek sails and I tried it out. The result was a green poly tarp (ugly) sail but it looked like a sail (go figure). Thing is I don't need (or want) a poly tarp main sail.
But I could use a crusing spinnaker!!!! So I'd like to try again with some generic tyvek (no logos). I CAN'T FIND A PATTERN ON LINE.

Anyone have an idea what the cut lines would need to be to get the proper shape ...?

Fair Winds,
Rob

[cockeyedbob]

sailrite.com ... worth a try ... made a sail once, looked like me granny's bloomers ...