I’ve been working on my latest font in the last weeks and have the Regular and ExtaBold almost ready. I’d like to make a Thin too, but what would be the best way to do this? Extrapolating doesn’t work out well. So should I first make a new Master and set it up in Glyphs and then interpolate from the Thin to the Regular and the Regular to the ExtraBold?
I don’t think that there are tricks to help you. You can extrapolate a tiny bit but in your case it is quite far off. So you need to draw the thin manually (and add it as a third master). To get started, you could extrapolate you existing masters and fix up the results.
Chris, I’ve done this before in the past for my font Nordic Narrow (https://www.fontshop.com/families/nordic-narrow). I’ve done it in FLS though, so I kinda hoped that Glyphs could simplify this process in some way. It’s got some fantastic features, so this could have been one of them (not that it should though).
The font I’m currently working on has got extensive stylistic elements and difficult OT features, so I see a sh** load of work coming my way. But I’ll take it like a man.