[The following description of Homasote was written by Gregg Fuhriman]
My Experiences
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Homasote is a material made of densely compressed newsprint, and is usually sold in 4' x 8' x 1/2" sheets. It is also available to the model railroad hobby as precut roadbed strips. My experience is
with the large sheets, which I purchased from a building supply store. In 1987, one sheet cost around 25 dollars.
I cut it into many 8' strips, using a rotary saw set at 45 degree angle to get the "ballast slope". The ascii drawing below shows an edge-on view of how I cut the Homasote sheets:
These strips were then used as-is for straight roadbed. To make curves, I cut dozens of kerfs crossways about 3/4 of the way through the strip and about 1/2" apart. The strip could then be "bent"
into the desired curvature by compressing the kerfs on the inside of the curve. The purpose of this exercise was to reduce wasted Homasote; it is not a cheap material.
The homasote strips were then glued to plywood sub-roadbed using carpenter's glue and clamps. I also drove small nails through the Homasote into the plywood to help hold things in the right position
while the glue dried. Special shapes, like around switch stands, were shaped by hand using a utility knife to carve the homasote.
Summary of My Experience and Netter's Comments
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Benefits of Homasote are that it holds spikes and nails well, and it is a sound-deadening material to reduce train noise. It glues easily, as it is a porous material. It is relatively "soft", so it
cuts easily.
Cutting this material with a power saw generated piles of fluffy, gray dust that went everywhere and proved to be a pain to clean up. I reccommend wearing a dust filter to avoid breathing in the dust
and fluff. Cutting with a utility knife is neater, but more difficult and tedious as the homosote tends to "grab" the blade (just as it "grabs" spikes and nails).
Forming curves with the kerf-and-bend method was not 100% successful. At least half the time the strip would break in two. Also, the resulting curve is not super smooth ... they are actually several
short straight sections. Heavy sanding can smooth out some of this (but with more dust).
Other netters have suggested painting the Homasote with a latex paint to help seal it against moisture (introduced mostly during ballasting, but also to guard against ambient humidity). Its
dimensional stability with respect to temperature and humidity has been panned, though I have not noticed problems with my layout so far.
How do I get the cork to go around curves?
Cork roadbed is typically provided in a split section, thin enough to follow normal curves in a given radius. One netter suggests soaking the strips in hot water first. This makes them flexible
enough to do about 8" radius curves before breaking.
My track doesn't have holes in the ties for nails. How do I hold it in place?
A construction cement called "Liquid Nails" will hold the cork and track in place. Just a thin coating of this with the track pressed down onto it will set in about 30 secconds... even with the 8"
radius curves which the flex track will not hold on its own.
An alternative is to use white glue spread with a finger over the surface of the cork. You will need temporary pins along the track to hold it in place while it dries.
I'm starting a first layout in my dorm room (4X6) and I'd like to hear some of the pros and cons of plywood and Homasote for the base of the layout.
Homasote is something you laminate on top of plywood. Don't use it "free hanging" from the benchwork. If you're using something like L girder benchwork with cookie-cutter trackbeds, one sheet of
plywood goes quite a way (because you can splice together the cutouts to make more track bed.
1/2" or even 3/4" plywood with an overlay of 1/2" Homasote is what I've seen used on industrial strength layouts. I'm using 1/2" Homasote on top of 3/8" plywood on my layout -- the downside of this
is that it takes more supporting risers to get a decently rigid roadbed with thinner plywood.
...
I'd recommend an open framework as being better for landscaping, but if you're sure you want one big flat area to build on, I'd recommend both: Homasote over plywood over a 1x4 frame. Homasote is
much easier to drive track nails into, not to mention removing them if you want to re-arrange your trackwork.
I'm using homosote for my HO layout roadbed base (cookie-cutter style). Do I need cork roadbed too? Seems the homosote would damper the sound and vibration just fine.
No you can use just the homasote. question you have to look at is the ballast section, that is the pile of ballast that real track sits on that raises it above the rest of the ground.
You can model that by putting homasote just under your track and cutting the edges of the homasote at a slope. Or you can put cork roadbed under the track on top of the homasote to lift the track up
off the surface of the homasote. You could use HO cork under the main tracks, N cork under the sidings and put the industrial spurs and yard tracks flat on the homasote. the different levels of track
help differentiate the different classes of track. the higher, better maintained main line has good drainage with clean rock ballast, with the siding slightly below it and the same size or a little
smaller ballast. The yard and industrial tracks are down in the mud on cinder or fine ballast (better walking surface).
Dave H.
In an attempt to make Homasote less susceptible to moisture, many have mentioned that they consider it a good idea to paint Homasote before laying it down. That being so, is it best to use a
water-based acrylic paint, or a lacquer-like paint?
Any water based latex flat paint will work. I check out the mis-matched section at my supplier's and can get a gallon of earthy looking paint for a dollar or two.
Dave in AK
About laying cork down for the roadbed? How do you do it glue, nail, staple?
Is there any tricks that I should know? Checking out the Cork Roadbed section should answer your questions.