Roadbed, subroadbed and benchwork

Boy Jose, you sure picked a question that will result in lots of divided opinions!

You'll need to make some decisions - if you want to simulate the appearance of well maintained prototype track, the track should be elevated above ground level simulating the gravel ballast the real RRs use to keep their track drained. But if you're modeling a bunch of run-down industrial spurs or a yard the tracks are unlikely be laid above ground level.

Let's talk matrials a bit - homasote holds spikes pretty well, is easily cut and shaped (although doing so can create an amazing amount of grey dust!), and is available in 4x8 sheets. The thickness of homasote can vary a bit from sheet to sheet. It's relatively stable with some evidence provided from some modelers that it can stand up even when soaking wet. But it's not very strong - don't expect it to not sag if used as table-top material (simulating the ground) - many modelers cover a plywood table top with homasote. Homasote is inert which means it deadens sounds - like the whirring sound of a bunch of model train wheels rolling along the track.

Rigid extruded foam (the pink, blue, or gray stuff depending on where you're located) is stiff and rigid. The 2" thick variety of this stuff is more than strong enough to use as a table top surface. It can be easily cut and shaped with saws and other tools (but doing so generates an amazing amount of pink/gray/blue dust with an electrostatic charge that will cling to everything-in-sight). It can also be cut with a hot wire cutter that actually melts the foam away. Foam is an excellent conductor of sound and laying track directly on sheets of rigid foam can cause those sheets to act like the sounding board of a piano and amplify the wheel noise of trains running on it. Foam is far to soft to hold spikes well so any handlaid trackwork will need a separate roadbed layer between the track and the foam - homabed (a pre milled variety of homasote from the California Roadbed Company) works well for this. Cork also can be used but it doesn't hold spikes nearly as well. The pink/blue/gray extruded foam is relatively fire proof (it's ok to use as insulating material in a house). Do NOT use the white bead-board styrofoam - struturally it is very weak, it's prone to chipping, and it is a big time fire hazard!

Plywood is another material frequently used for table tops. It's relative stong and readily available in many grades nearly anywhere in the world. Its somewhere between homasote and foam in terms of sound transmission. If you can drive spikes into it they'll stay driven - however you'll be likely to bend an awful lot of spikes trying to spike into it. When I lay track directly on plywood I drill pilot holes for the spikes to avoid this. If track is mounted on roadbed (homabed or cork) the spiking issues disappear. Plywood is relatively easy to cut with a saber (jig) saw or most other kinds of saws. Dust is created but it's no where near the problem of the dust from homasote or the rigid extruded foam. Plywood is flamable but doesn't represent a special fire hazard unless you follow unsafe wiring practices.

There are other materials that have been used for a table top but I'm not going to mention them here.

So what materials should YOU use? Let's talk some more about your layout. Are you planning a relatively flat layout? In this case any of plywood, a plywood/homasote sandwich, or rigid extruded foam will work pretty well for your ground surface. The foam offers the advantage of easily being able to carve drainage ditches if they're needed. I'd recommend some kind of roadbed to lay on top of the table/ground surface - especially if you're using the foam. But if you're modeling an industrial park or a yard track directly on the table top (ground) surface is fine. If you're using foam for the ground you'll probably want to glue the track down because the foam won't hold spikes or track nails).

But if your dream calls for hills and valleys with track on grades you might want to use that plywood homasote sandwich (or just straight plywood). Cut alongside the places where the track (like a cookie-cutter) and lift them to their desired elevations. If there are big valleys or river beds keep a layer of plywood (or plywood/homasote) at the bottom of the valley or roadbed and raise the surrounding landforms (roadbed or hills) above those river bottoms.

If your dream calls for LARGE mountains and valleys with the track twisting around them you might consider spline roadbed. This is a more advanced techinique that lets you use your material more effectively. Popular spline materils include clear pine or fir, masonite, and homasote. I have made use of masonite splines on my layout. For splines you cut strips of the material, stand them on end and laminate them together. Here's my web page on building spline roadbed - http://s145079212.onlinehome.us/rr/howto/splines/index.shtml

So!What will you do? Maybe the best way to decide between homasote and foam is the check the availability of each - the big box stores like Home Depot tend to carry the foam but you may need to search to find homasote (seach for Homasote on the web). If you're planning on doing a bunch of handlaid track I'd suggest going with a plywood/homasote sandwich. Otherwise the foam might be the easiest way for you. If using foam I personally would use some kind of roadbed (homabed or cork).

Note: Cork roadbed is relatively cheap, bends around curves very easily, holds spikes (sort of), and provides sound insulation. But the stuff dries out with time. Homabed won't dry out and holds spikes well but is pretty expensive. Somehow you can't win... If you elect to skip the roadbed and lay track directly on the foam it won't be the end of the world. The layout can still look pretty good.

When gluing foam together don't use solvent based glues/cements as they will disolve it. The foam also present an impermiable barrier to air - if the laminate two sheets of foam together with latex construction adhesive you can expect that the glue won't dry on the inner parts of the joint even years after constuction. So I smear the surfaces with the glue and let them start to set up before I put them together.

This is probably more information than you can digest at once so take it easy. Read it a couple of times and I'm sure others will post also.

Good luck, and let us know what you chose and how it comes out.

Regards,

Charlie

Charlie has a lot of good

Charlie has a lot of good pointers.  here's some expansion:

If you use Homosote in the SW, you MUST seal it - otherwise the monsoon change in humidity will warp it back into newspaper!

Foam alone has two nasty habit due to it's instablity.  First, anything you put in the surface that gets a lot of abuse "Floats" in time - switches, bad track section requiring additional spiking, etc.  Second, it may be hard to line sections up with foam because any holes will get bigger over time - so you should consider a frame under foam in a permanent setting - and for modules too.

Plywood is best at first, but it IS heavy.  Don't say I didn't warn you!!

Next up we get to L-Girder - this is the most involved way to build model railraod benchwork, but there's a reason everybody uses it.  First, it gives you a study platform.  Second, you don't have to lay a plywood sheet on top of the girders - you could go ahead and put in Spline roadbed and skeletal framework to hold up everybody's favorite hardshell scenery.

Onwards to the Roadbed!

One option between WS black foam bed, which is extremely easy to lay down, but like all foam products it physically breaks down over time.  This has an adhesive that over time hardens as the foam weakens, leaving behind a tough adhesive layer when you go to remove it for expansion.

Cork is the hobby standard and for good reason: it is durable, pliable, and it holds things almost as well as wood.  Put a layer of cork on plywood and you have a great foundation for spikes and all other things you have to plant.  the cork holds the nail up, so then you can find a nice hammer and tap and tap them home.  You put it down with white glue, and when you want to take it out for a track plan change, a little water brings th glue back so you can cut and rip as necessary.

The newest one I have seen seems to be the most involved: spline roadbed takes a material like strips of plywood on its side or PVC pipe and strings this along the top of the benchwork, curving as necessary, to follow the track plan.  This method provides the maximial amount of scenery manipulation, and it gives you a perfectly level roadbed subsurface, but it will be far more work then slapping a sheet of plywood on a frame made of 2x2s or 1x3s.

Sub-roadbed and roadbed

Since you've gotten the plus & minuses of the various materials, I'll simply state what I'm using, and why - I've got foam, of a couple different thicknesses, over 3/8 plywood and box framing. The box framing is cheap and easy, the plywood offers stability and strength, and the foam offers flexibility.

Then I used cork for my roadbed. It's inexpensive, it works, and for yards it comes in nice large sheets.

For large sheets of cork,

For large sheets of cork, look up school supply outlets on the internet,  You can get large sheets 4 feet wide for lengths...well, lets jsut say you don't have a room long enough for their liogest available lengths!!!

I seem to recall paying 20 bucks for a 4x8, though it might have been higher or lower.  Midwest cork costs about 1.00-2.00 per strip, unless it went up again.

My two cents in two comments..

Just to add to the excellent posts here..

1. I found foam to be a "thick" surface which made running feeders and installing switch machines a little more problematic. I prefer plywood.

2. I found WS foam roadbed to be a pain to work with. The natural spring of cork makes nice smooth curves and transitions. The centerline for the stuff I have used has always been right in the center making it easy to follow a drawn centerline. It sands well. In contrast, the WS stuff does not make nice natural curves. The two boxes I aquired both had off center cuts making it hard to follow the centerline. It did not sand as well. I also thought the height was a l ittle low. After using both on my little 3x6 (I used to say 2x4 but recently re-measured.. it needs a diet..) layout i ripped out all the WS stuff and relaid with cork.

Chris

Agree with Chris

I've tried the WS stuff and I don't like working with it.  Cork gives you more height and is easier to work with.  I haven't tried spline.

Cork is the only way

I have tried.  I think I'll stick to it.  I have never liked the WS foam concept.  Call me picky.

Sub-roadbed and roadbed

 I use plywood on my home layout, and have used foam for portable layouts, both work well. Under the track I use laminate flooring underlay. This paper based product is cheaper than homasote, cuts easily with a knife and is about ballast thickness for HO. I lay it right across the track area and then cut it to the correct profile after the track has been laid. It is not affected by soaking with dilute PVA for gluing ballast. In fact I tried dropping a bit in in some water, left it to soak, had no effect! I normally seal the top surface with cheap acrylic varnish as I find it holds spikes better. 

Mike Ruby

Best Roadbed Material

Thanks for all the comments on this post.  I am about to build my first layout and these comments really helped me a lot.

bruce

I disagree with Benny on spline

I disagree with Benny that spline is a lot more work than plywood sandwich roadbed.

Once the spline is cut, installing it is a piece of cake - one of the secrets with masonite spline is once two splines have been installed and set up, they hold their shape so adding the rest of the splines is quite easy.

I would come home from work, head for the basement - and in 10 minutes have a two-center-spline pieces installed on the layout. Then after dinner, I'd come down and glue on the outside splines in another 10 minutes. Just before bed I'd take 10 minutes and raise the spline into place on risers (but not fasten it to the risers yet). Next day after work I'd take 5 minutes and run the screws through the spline into the risers. Then I'd move on to the next 8-foot section and repeat the process.

In a few hours each week, I'd install over 40 feet of mainline roadbed, complete with easements - minimal sawdust, no muss, no fuss. If I had used plywood, I'd have to manhandle sheets of plywood, measure, mark and cut them with a saber saw, make a terrible sawdust mess. To connect the sections of plywood roadbed, I need splice plates ... and let's make sure when marking the plywood I include easements.

Sure I make a mess when I cut the spline initially, but that's one big advantage - the mess and fuss is all up front - then the install process is very relaxing and practically automatic in its ability to create easements and to make proper vertical curves. Hardly what I would call "difficult".

Greetings, Benny said: "One

Greetings,

Benny said:
"One option between WS black foam bed, which is extremely easy to lay down, but like all foam products it physically breaks down over time.  This has an adhesive that over time hardens as the foam weakens, leaving behind a tough adhesive layer when you go to remove it for expansion."

Can you explain this more?  I have open and closed cell foam products that have been around for years and I have not seen them break down.  I have old toys from the early days of plastics where the surface of the plastic has become sticky.

How long will it be before this break down starts?

I grew up with cork roadbed on my Dads layout.  I remember that he had to replace sections of track as the cork dried and crumbled.  When I built my first layout the WS roadbed had only been on the market for a short time and I decided to give it a try.  It seemed to hold up well and when I took the layout apart I did not notice it being different then when I put it down.  Now, I must admit I was ripping the whole layout apart to make way for house remoldeling and a new layout.

I am NOT flaming Benny here.  I just want more info as my current layout is having the WS roadbed on top of homasote.  This currently layout is to be a long term layout.  I am thinking between now and when my son is at least out of high School, he is currently four.

Thanks,
Christopher

Well understood; I'm relaying

Well understood; I'm relaying information from those that used this material elsewhere. and have had these experiences when they were trying to remove the old foam roadbed.  You may not notice any changes in five years time.

Homosote will change shape depending on how wet you get the layout.  In my case I ballast and scenic by the water method [I use enough water to suck the glue up through the dirt material].  I could not use Homosote even if I wanted to!  But homosote does take spikes very nicely.  Plywood takes them like wood takes nails...you need a hmmer!

Regardess of the type you use, I find roadbed to be a one use product.  After that it is best to grab a new box. 

If you are ballasting, then once you have ballasted the cork should be siginificantly sealed and not crumble or crack - I've never had either condition.  But then my layouts were up for only a short couple years or so.

Joe, I'm comparing spline roadbeds to plywood sheets supporting a foam subase such as the woodland scenic risers.  With this method I could go from bare level plywood surface to cork roadbed in about four hours on the entire layout.  I think youc an see the problem with this construciton technique: it's TOO QUICK!!!!  In short a mistake gets a lot further very quickly becasue there is not enough time between each stage in testing and rethinkign precisely what is being done.

Homasote

Benny,

I have always used homasote and I do my scenery the same way that you do and I have never had an issue with homasote. I live down here in South Florida with extreme humidity and weather and never had the issue with any homasote. I love it because it is easy to "plant" things into it is a great insulator pluse it cuts down the noise factor.

Spline Roadbed

I have used cork on plywood, however I am constructing an around the walls shelf layout in a large (1800 sq ft) basement.  My towns and yards are constructed on dominoes, but I would like to try spline for the mainline between towns.  I am a "Lone Wolf Modeler" (by location and not by choice) and don't have a source for the splines.  For my dominoes I have my local rural lumber yard rip 3/4" A/C plwyood into 1x4 lumber.  They charge me a small fortune for this, but it is still less expensive than buying good quality 1x4 lumber.  They will not cut the masonite splines.  Any ideas?

If you live close to me I could help

Jim where do you live?  anywhere near northwestern Virginia?

Thanks

My basement is located in northeast Kansas, near Topeka.  I work in rural southeast Colorado. When we bought our last basement (house), we decided to keep it and return there to retire in the next 5-10 years.  We have a small apartment near my job in Colorado and I bring dominoes (modular layout sections) to the apartment to work on and return them to the layout in Kansas.  I also work on the layout when I am home for vacations, long weekends and holidays.

I appreciate your offer of assistance.

Anyone familiar with Vinylbed?

Anyone had much experience with Vinylbed?  I'd be particularly interested in any comments comparing Vinylbed with California Roadbed.

Roadbed

I noticed some good discussion about the roadbeds and base. I like the idea of foam as it can be used to make terrain that is below track level. I played with homasote at one point and it was great for holding the nails. One thing I did not see was attachment methods, other than nails. An MR, about 4-5 yrs ago, discussed some options to mounting the track. This included RTV, although I think this was short term planning use, and topper tape. The topper tape is double sided foam tape used to isolate truck caps from beds. Not only do you get a sound deadening effect like cork, but the adhesive holds the track to the base material.

Stogie

Pictures for the spline roadbed

Hi Joe 

Do you have any info or pics on the spline roadbed. I'm using 3/4 finished plyboard in cookie cutter style and it might be easier for me in some areas to use that system. I can buy cheap masonite strips 3mm thick and 1 inch wide, would that work?  

James B

Spline tutorial

One more option

Driving rail spikes into plywood is tough.  On a cookie cutter layout, I tried cutting sheets of luan plywood, the stuff they use under flooring, into roadbed and gluing it to the plywood.  I glued the ties to the luan, and spiked the rails to the ties after ballasting.  The spikes were fairly easy to drive but stayed extremely well.  It wasn't noisy either.  I believe I'm going to go this route on my next layout except I'm going to use splines as a base.  (Thanks Joe!) 

Manofcountry, Joe F made a great video of creating splines.  It's all you'll need.

Bart

getting feeders and/or other wires through the surface

Just a comment about thickness and density of the layout/roadbed surface;  one of the best and most inexpensive and simple ways to get through to the underside of the layout is - a straw!  I can't take credit for this; David Popp on one of his MRVP segments just mentioned it (or it might have been in an article in MR), very casually, but it's a GREAT idea!. Just obtain hollow coffee stirrers (usually always free with your takeout coffee) and drill the appropriate-sized hole(s) for them wherever you have to get things through to the underside. Then just stick the straws in the holes, run the wire through them, and pull them out when you're done. If the wires are thicker than usual, use soda straws instead. It's one of those "Why didn't I think of that?!" things...

                                  Fred B

How do users of spline roadbed do it without a table saw?

Just looking for a reasonably priced way of doing this when you don't have room for such a tool.  Farm it out?  If so, what costs does that usually entail?

I am using a homosote roadbed

I am using a homosote roadbed made by Cascade Railway supply. It's a great product and easy to use.

Barry