Tehachapi, BC

[robert3985]

...* I bought some blue foam board for a house project, with the intention of possibly using the leftover for scenery work.  Sadly, my opinion of the stuff has not changed since I last tried it years ago: I like the result, but I HATE THE MESS IT MAKES, especially when the humidity is low.  Any tips on clean-ish ways to work with foam?

Gary... Blue, pink and purple foam are just messy, no way around it.  However, the less you cut, use a Surform tool on, or rasp, or sandpaper, or wire brush...the less mess you'll have.  A couple of tools that keep the mess less, are common knives of various blade types (My favorites are (1) a cheap filet knife that I can sharpen with a few swipes of a carbon-steel kitchen sharpener, and (2) a stainless steel, long serrated bread knife.  A lot of cutting gets me pretty close to my final scenery base contour, but the least messy (but stinkiest) is my homemade hot-wire cutter, which gets me down to where I can start texturing the surface with various scratching and carving tools.

I too keep a small shop vac (with a good filter in it) handy, or going simultaneously (depending on how I'm arriving at the final texture/contour) with my "carving".

I find that if I carve a bit, then vacuum a bit before there's a big pile of extruded Styrene dust, the mess doesn't migrate around the house nearly as much.  I'm also careful to vacuum the soles of my shoes before I move to a clean spot in my trainroom...and then I vacuum my shirt and pants as well when I leave the trainroom so as not to take small particles of extruded Styrofoam into the rest of the house where my cats might ingest it.

The two vacuum tools I use most are the brush and the crevice tool.

This works well for me...

Cheerio!
Bob Gilmore

[C855B]

Yes, XPS is messy to cut, and you need ample room for the sawdust to fall and not fly everywhere and coat everything. Your close quarters are going to work against you. But like Scott said, keep a shop vac near and don't save cleaning up for just when you're finished with the entire job.

Of course, sweeping it is futile.

However... it just dawned on me... you aren't cutting it with a circular saw, are you? That's asking for it. Sabre saw only, otherwise, hand saws. I cut it on my table saw once... OMG, what a bloomin' mess.

One more thought - it's probably going to be obvious to your scientist mind, but don't use plastic dropcloths to shield stuff from the dust. I use canvas painter's drops.

[Cajonpassfan]

Gary, it's looking great (and neat)! Looks like a lot of progress...
I know lots of guys use foam and swear by it, but after helping a friend with his scenery using foam, I will NEVER allow that stuff in my house, I don't care how neat you try to be, the s**t gets EVERYWHERE 
I'm just as happy using good old-fashioned hardshell with specialist bandage and plaster.
To each his own I guess...
Otto

[GaryHinshaw]

Thanks for the feedback on the foam.  I was hoping someone had found the perfect tool that was flexible, but firm, and cut through foam like butter w/o releasing toxic fumes.  I guess the vacuum is still the key ingredient.  With the upper deck mostly ballasted now, I'd love to start getting some landforms in place, in time for the McGrattan train.  (But getting track work done is still a higher priority!)

Low humidity...  it seems to me you have the ideal place to use foam from that perspective.

Normally true, but we're in a bit of an arctic outflow this week: -7 C now with dew points around -17 C.  Maybe I'll try again when the rains return.

[C855B]

I have that wavy sabre saw blade - sort of like a bread knife - that was very cool, and had (still has!) great promise as a dustless, non-stinky solution. But unfortunately you can't use it for long cuts in thick foam, as the blade binds not but a few inches in. I do anticipate making great use of it when I start to carve scenery.

[davefoxx]

Per @Ed Kapuscinski's recommendation, I now use a cheap snap blade utility knife.  The blade probably extends about three inches, which allows you to cut up to 2" foam and still get all of the way through, considering that it's best to cut with the blade at an angle to the work.

Check this out.  I cut this teardrop-shaped piece of foam by hand, by cutting a shallow cut and then going back with deeper cuts until all of the way through.  By angling the blade, it was easy to stay within the previous cut and just sort of drag the blade through the previous cut.  The blade is also just flexible enough to bend to follow that curved cut.



In the past, I also used a sander in one hand and a wet/dry vac in the other hand to control the dust.  Once I discovered the snap blade knife, I don't use the sander anymore.  I just carve or whittle the foam to its final shape.

Hope this helps,
DFF

[GaryHinshaw]

More good ideas - thanks.  (But I'm surprised that a sabre saw could bind in foam.)  I won't give up on the stuff just yet.

How do folks prefer to model mountains with foam: horizontal or vertical layers?  I'm thinking of this scene, in particular:



(I hope Google doesn't let me down with this link.)

[eja]

Way back in the day ... a two bladed GE electric carving knife as the must have kitchen accessory and Christmas gift.

These thing work wonders for carving, cutting shaping any type of foam and produce little of no "dust".  Search the thrift stores .. perhaps you can find one.

ed

[C855B]

Way back in the day ... a two bladed GE electric carving knife as the must have kitchen accessory and Christmas gift.

And available at most garage sales.   I have an electric carving knife in my foam kit, too. Like the sabre saw with the bread blade, it binds - and sooner - in thick foam. The issue is the knife cuts do not leave a kerf, so in the 1-1/2" and 2" foams, their structural nature closes the cut in after the blade. Bind city. Dave's approach with the disposable utility knife works probably because it compresses the foam in small increments, leaving enough of a kerf to work it down, not to mention that the knife is much thinner than the power tool blades.

The power knives work well for cuts close to an edge, where the material flexes enough to curve away and leave the blade clear. I hate the foam dust, too, and really wish I could get the power knives to work, but am stymied every time when I ignore my own findings and try it again, just to be reminded.

Seed of an idea... what I have not tried is inserting a door shim into the cut after starting it to wedge it open, theoretically freeing the blade. Worth the attempt.

[Scottl]

How do folks prefer to model mountains with foam: horizontal or vertical layers?  I'm thinking of this scene, in particular:

Is there a particular structure to the landscape?  I would always use the foam oriented to the gross landform orientation if possible.

[coldriver]

I use pink foam almost exclusively and the best tool I've found is a hacksaw blade (without the frame...).  You can bend it to whatever contour you like and the mess is fairly minimal. 

[GaryHinshaw]

Thanks for the suggestions.  I can try a hacksaw blade this evening.  The other ideas will have to wait until I return from a (cold) work trip to the Interior.

Is there a particular structure to the landscape?  I would always use the foam oriented to the gross landform orientation if possible.

Good question Scott.  This is Tehachapi Creek Narrows near the top of the climb.  Here is roughly the same angle as my model photo:

http://www.railpictures.net/photo/581323/

and looking the other direction towards Summit:

http://www.railpictures.net/photo/576574/

Here is a good trackside closeup:

http://www.railpictures.net/photo/221639/

Sandstone?

[Santa Fe Guy]

Gary Re modeling land-form, when a friend and I modeled the Thompson River Canyon in N Scale back quite a few years as published in N scale Railroading we stood the foam vertically for all of the mountains and over the track when forming tunnels. It made the job of profiling very easy without a lot of mess. [ Guests cannot view attachments ] [ Guests cannot view attachments ] [ Guests cannot view attachments ]
We used a sharp disposable blade to cut the profile then the messy part came later.
These might help explain better.
Rod.

[Chris333]

To carve up scenery I use the cheap snap-off blade knifes. The heat from cutting will dull the blade so I keep a small sharpener close. I recommend the Olfa cutter SRV-2 

But to cut large pieces of foam just use a jig saw with a leather cutting blade and there will not be a single crumb on the ground. The ones I use look just like this:
http://www.ebay.com/itm/VERMONT-AMERICAN-JIGSAW-BLADE-30022-Leather-Rubber-Blade-2-Pack-/151027487876

Like a knife blade, but not sharp to the touch. They have never bound up at all, but at around 2.5" thick the blade might not go all the way through.

[Scottl]

I did not know anything about the local geology.  Here is an useful link

https://socalgeology.com/2016/04/22/blog-ca-58-bakersfield-to-tehachapi/

From the pictures you linked it looks like you have sedimentary units outcropping in this scene.  However you will note that there is a lot of geological change over the length of the route.

I would probably arrange the foam board horizontally in this case, as the slope facets are broad and relatively uniform.  The bedrock is cruddy and does not hold a slope particularly well, so I would avoid vertical orientation of the board, which tends to form vertical irregularities and needs a lot of work to smooth or a thicker cover coat. 

Given the geology, I'm a bit surprised these tunnels still exist.  I assume they are concrete-lined?