Furka steam railway

From Luzern to Interlaken. The Furka railway would be a diversion from that route. September or May would be the time of year we would be traveling.

Doug, The Dampfbahn Furka is nowhere near Luzern or Interlaken. It would not be a side trip. I doubt you could do it as a day trip. Look on a map to see where it is. Swiss rail map: https://www.sbb.ch/content/dam/infrastruktur/trafimage/karten/karte-sts-pass-gueltigkeit.pdf
You cannot travel in a straight line in the Alps, which is why it has all these scenic but circuitous railways.

The official website is here: https://www.dfb.ch
In 2017 they are running from 24th June to 8th October. And, apart from 5 weeks in July/August it is weekends only. So May is no possibility, September possibly..

It would be quite a detour. Looking at this upcoming Saturday:
Leave Luzern at 7:18 am getting to Realp at 9:50 am, with train changes at Erstfeld, Goeschenen, and Andermatt.
10:15 Furka steam train arriving Oberwald at 12:30 pm.
12:50 pm Postbus over the Grimsel Pass arriving Meiringen at 2:34 pm.
2:51 pm train arriving Interlaken Ost at 3:24 pm.

A true Trainspotter should have no problem with this. Normal people, hmmm.

Hi everyone and thanks for your replies. It now looks like we will be in Switzerland in September of 2018 so theoretically snow should not be a problem. Also we never intended it to be a day trip and have lot's of time so the schedule that Sam suggested (see below) would not be a problem for us. We were hoping to hear from someone who had ridden this train and could hear an opinion of it. Again, thanks for your replies.

(Leave Luzern at 7:18 am getting to Realp at 9:50 am, with train changes at Erstfeld, Goeschenen, and Andermatt.
10:15 Furka steam train arriving Oberwald at 12:30 pm.
12:50 pm Postbus over the Grimsel Pass arriving Meiringen at 2:34 pm.
2:51 pm train arriving Interlaken Ost at 3:24 pm.)

Steve, thanks. Your reply was very helpful.