Making Pink Foam boards level?

[chicken45]

I have yet to come across a board of pink foam that was completely flat. There are little waves and troughs here and there. I can't exactly put it through a planer and get it level, so my question to you folks is how do you level it?
Yeah, sanding block, but I don't know if that's precise enough. And maybe it's not even a big deal after roadbed and ballast. I can't imagine a hand plane working well.

Suggestions?

[Hornwrecker]

I use a Shinto planer saw rasp.  It is the best tool I've found for leveling foam and cork roadbed.

http://www.popularwoodworking.com/woodworking-blogs/chris-schwarz-blog/the-venerable-and-inscrutable-shinto-rasp

Now grasshopper, when you can grasp the rasp from my hands, you can leave.

[chicken45]

Bob,
This?
http://www.amazon.com/gp/aw/d/B001AWZ4S0

[Chris333]

I use a 2' long flexible steel ruler to find and work out the dips. If there is something major I will sand the foam, but usually wait till the cork is glued down and spend my time smoothing that out. If there is a serious dip you can build it up with layers of masking tape and glue cork over that.

[Chris333]

I'll throw in that I sand by wrapping sand paper around a 1x2 scrap. Use the straight edge to find and mark where to sand, sand, re-check and re-sand as needed.

[Hornwrecker]

Bob,
This?
http://www.amazon.com/gp/aw/d/B001AWZ4S0

Yeah.  I'll show you how it works, and you can try it out.  It's what I used to shape most of the foam on my layout and the other ones I've built.  At least for all of the flowing stuff; used coarse rifflers for detail foam forming.

[davefoxx]

I use a 2' long flexible steel ruler to find and work out the dips. If there is something major I will sand the foam, but usually wait till the cork is glued down and spend my time smoothing that out. If there is a serious dip you can build it up with layers of masking tape and glue cork over that.

+1.  I had such a severe bump between two sections of 2" tongue and groove foam on my last layout, that I practically had to sand through the cork roadbed to smooth out the track alignment.  Once I carved in drainage ditches along the alignment, you would never find that spot.

I don't bother leveling other areas, because that's a waste of effort.  Besides, I'm intentionally trying to avoid level areas on the layout (except the track), because they are rare in the real world.  I've added hills and dales (even if small) almost everywhere on my current layout.  I think this can make a layout look larger, too.

DFF

[chicken45]

One thing I am worried about is how steam engines run on this. My HH1 tender likes to derail on anything less than perfect. It's my second favorite engine and it will break my heart if my track sucks.

I aquired said Shinto rasp today. I'll be planing off the WS roadbed remnants. I think I'm probably going to do cork this round...at least for the turnouts and interlockings. WS lays a great curve.