In the Kalmbach book on Benchwork, it shows the method that Bill Darnaby uses of simple 1x2 supports out from the wall every 16" with nothing else but 2" foam as the benchwork. A beautifully simple system for railroads with no elevation changes. Well, I need a grade of up to 4% and I was wondering if 2" thick rigid foam would deflect enough to make that work? The majority of the shelf would be at a fixed height on risers while a trackwidth of foam at the front would be on a downgrade of 2% or 4%. Would the foam snap instead of bending smoothly? Or should I actually break the foam and use plaster/sculptimold/etc to patch the transition? Sanding down flat foam to a grade does not seem to be a great way to get a smooth grade, nor does cutting the grade out of the foam. What are your thoughts?
Richard KurschnerSuperintendent, Lynnsport & Eastern
Use Woodland scenics stuff for the rise. Only way to do the other is heat or layers of thinner foam, both unpredictable.
A long enough piece of 2" foam would bend -- after all, a 1 foot piece of prototype rail would not bend, but a 39' lenth of rail will bend; likewise a 1 foot piece of 1x4 lumber won't bend, but an 8 foot length will -- but I am not sure you'd get the bend you want in the distance you want it to bend in.
An extremely lengthy 4% grade might be possible, and indeed the rigidity of the foam would give you very nice natural easement curves at the ends of the bends, but you do not say what your distance is for the beginning and end point for this grade. In most cases of home layouts I suspect the distance is too short to get the bend you want with the lengths of 2" foam available.
Dave Nelson
rrebell Use Woodland scenics stuff for the rise. Only way to do the other is heat or layers of thinner foam, both unpredictable.
Short answer: what he said.
I have 2" foam on my entire layout as the subroadbed, and while I have the same benchwork book to which you are referring, you would have to have at least a full 8+ foot long piece of the foamboard in order to really get the kind of elevation change you are looking for.
So if you are going to make a loooong run you might be able to cut along the long edge of the foam and gently lift it while shimming up the underside somehow.
[I wouldn't even attempt this if you aren't going to have a plywood base underneath the foam. I believe Bill (and Lou Sassi in his scenery book) just built a simple 1x3 or 1x4 open grid bench and glued the foam to the top of it; this will definitely make it harder to shim up the foam riser section.]
Andy
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Milwaukee native modeling the Milwaukee Road in 1950's Milwaukee.
https://www.flickr.com/photos/196857529@N03/
dknelsonA long enough piece of 2" foam would bend -- after all, a 1 foot piece of prototype rail would not bend, but a 39' lenth of rail will bend
Yes, even steel reenforced concrete bends when it is long enough.
For our model railroading purposes, I would say 2 inch foam does not bend. We made lots of very rigid cosplay props from it over the years, like this staff.
-Kevin
Living the dream.
I just did a scientific experiment. 30-inch by 30-inch square piece of 2-inch rigid blue foam. Two hands and one knee. It did not bend. Not at all.
Hope this helps.
Robert
LINK to SNSR Blog
LinesWestFanSanding down flat foam to a grade does not seem to be a great way to get a smooth grade, nor does cutting the grade out of the foam.
First of all to the forum. You initial posts will get hung up by moderation.
4% is on the steep side for grades. Are you sure the engines you have and the rolling stock you want to use will make it? You may want to test first.
Somewhere on Youtube, Ken Patterson has a video (the are impossible to search by key words) where he made a grade using 2" layers of foam, and a laser light level. He uses pruning saws and electric chain saws. He made it work.
I glued 1" on top of 2" and with a sureform and sanding made a 2% grade. It was hard to make it an even slope. I am satisfied but I will never do that again.
Besides it's inherent stiffness, how would you even get 2" foam to bend? Maybe you could screw it down with fender washers and then elevate the upper end, but I think the washers would rip through the foam.
Henry
COB Potomac & Northern
Shenandoah Valley
Go to your local Lowes or HD and see how well 1" rigid foam bends. Should bend a bit better than the 2". Then just sandwich it to make the 2" to match your base foam. Stagger the joints in the foam 'cause you need 8' length of run for a 4" rise @ 4%
BigDaddyBesides it's inherent stiffness, how would you even get 2" foam to bend? Maybe you could screw it down with fender washers and then elevate the upper end, but I think the washers would rip through the foam.
The only way you could possibly do it would be to secure the foam to a plywood base with the proper adhesive - except for the thin strip you want to elevate, which you would leave unglued. In any case, foam this thick doesn't "bend" in the way the OP might be hoping.
I've made a couple of smooth grades from foam by cutting the foam into a long wedge. It works better if you cut the underside and leave the top smooth. You do have to deal with transitions from level to grade and back to level at the ends.
It takes an iron man to play with a toy iron horse.
I concur with Robert, and used the same methods as Henry and Mr. Beasley to make grades.
The track grade/bed was cut out using a shur-form tool.
I stacked foam pieces, than carved the features, and the track bed profile.
Mike.
My You Tube
I like the QuadGraphics semi Mike. I can tell you are in the Milwaukee area haha. Is that a Walthers product?
No, my son gave that to me. He also gave the grandson the same truck in "O' scale. He worked for quad for a few years. Not sure where he got them.
Yep, I'm about 40 miles, SW of Milwaukee.
You can get a bit less than 2% by streching the inclines a bit on WS stuff. Also this kind of thing helps with the easements. Keep in mind that even a 2% incline man not be liked by your engines under load. My last layout was flat as far as the accual track excenpt for a small run of 4% plus on a side run up to a yard less than 2', all worked great. New layout 2% grades, major issues on long trains as the 2% is about 14' long. Luckily layout was intended for 7 car trains only but I was just playing around.
Incidentally, kerfing or relieving the back side of this foam works analogously to how it does in wood. You can bond a straight piece of flexible stock to the 'back side' once you have the curve jigged, if you want it to 'hold alignment' for installation -- just shim that layer. Use expanding foam or perhaps 'foaming glue' injection if you're concerned with any sub grade 'voids'.
(This is for closed-cell elastomer foams, not beaded 'Styrofoam' or its like -- but we all know that instinctively already)
OvermodIncidentally, kerfing or relieving the back side of this foam works analogously to how it does in wood.
Ah! A good thought. I could see that working.
But as mentioned above, seems like a lot of unnecessary labor when you can just get the WS risers and use foam tack or hot glue. To each his own I guess
The Milwaukee Road WarriorBut as mentioned above, seems like a lot of unnecessary labor when you can just get the WS risers and use foam tack or hot glue.
But it is one of the best ways to get precise roadbed line and surface if that's perceived as valuable... for example setting up for superelevation, transition spiraling, and vertical curvature all at once ... to be negotiated by Proto 2K PA trucks...
LinesWestFan Well, I need a grade of up to 4% and I was wondering if 2" thick rigid foam would deflect enough to make that work?
All this not-interesting technical discussion of contruction methods, which I might have started, is not helping the new member OP.
The answer to his question is "NO", plain and simple.
2" think foam will not bend as he wants it to... period.
He could make the base from 2" foam for support and also use a thinner piece of foam for the top surface that will deflect up to 4% as he wants.
Simple solution... 5/8" thickness added.
OvermodAnd when did I EVER eschew sesquipedalian technological overkill?
Haha! I can see you do not suffer from Hippopotomonstrosesquippedaliophobia.
The Milwaukee Road WarriorHaha! I can see you do not suffer from Hippopotomonstrosesquippedaliophobia.
And worse yet, I have to let you know you misspelled it.
(Perhaps worst of all I'm leaving it up to you to figure out where... )
LastspikemikeAn "o" should be an "a" as far as I can tell.
Then keep going. There are more.
As a hint, there is a legitimate phobia of long words, and its technical term is spelled correctly...
Incidentally, every instance of this 'word' I could find on the 'Net is badly misspelled from first principles, so Andy gets no poor marks for trusting the wrong pedants.