First off, the obligatory rant against the big box stores like Lowes: ()@()&#^#^#&^#^(#&&#(&(^^$
Okay, moving on…
So, as I mentioned on the coffee pot, I’m building a portable viaduct to run over the temporary layout that I have set up. This will have four pieces, two 180 degree curves and two straights, connected by four bridges. I’ll be running Fastrack on them.
On to the first problem: I’m trying to create a template based off of set of 4 connected FasTrack curves - I want to have the curves of the viaduct protruding an inch beyond the inside and outside of the curve - how the hell heck (oops, gotta watch what I say, otherwise I’ll be offending someone’s virgin ears) do I draw that? It’s been driving me up a wall today.
Also, after looking at different types of wood, I need to find one flexible enough to run around the inside and outside of the viaduct. Peg board would work great, except then I have to go about filling in all the holes. I’m not sure about masonite - I could only find 8’x4’ sheets and those didn’t lend themselves to testing their flexibility. Paneling is too rigid - tested a couple of scrap pieces and they snapped.
What you need for drawing those curves is a trammel. A piece of some stiff material (like masonite) will do. Drill a small hole near one end of a strip of that material. Drill another hold (D - W)/2 - 1 inches distant from the first. Drill a third hole (D + W)/2 + 1 inches distant from the first. D is the Fastrack curve diameter (36 inches, for example). W is the width of the Fasttrack roadbed (around 4 inches, I think). Pin the first hold in the middle of a straight line drawn on the template serface (perhaps one straight edge of the template material) by nailing it loosely. Then draw two semicircles with a pencil stuck into each of the other two holds as you swing the trammel through 180 degrees, from the line (or edge) around to the line.
Use a Yardstick for your trammel, if your curves are not 072 or larger, 054 will work fine. drill your pivot hole on the one inch mark, and so long as you remember to subtract that one inch, it is very easy to drill any radius/diameter points on your trammel. Yardsticks are usually cheap and the holes shouldn’t prevent it from being used for regular duty in the future.
Spanky … did you try luan plywood … the thin one ? I think that may be what you need … I may be wrong … but that’s what I use alot of and it’s alot more flexible than regular plywood … I don’t know exactly what flexing you’re doing without being there … you can wetten it with hot water and form it … making it more flexible … and then clamp or fasten it down until it dries . Now I don’t mean soak the devil out of it . It’s bucu more flexible than masonite .
Thanks everyone for the responses so far - the idea for a trammel is exactly what I was looking for. I’ll pick up a piece of wood (or a yardstick) on the way home from work.
Ole Timer, the idea for luan plywood is a good one - the problem is that Lowes (*&^@$%^&$%#) doesn’t carry it. (But they do have containers of liquid Tide if you need to do laundry, or blenders if you’re in the mood to make a daiquiri!) I’ll have to see if I can find a local lumber yard that carries it. By the way, the diameter of the half circle I’d need to bend it in is probably around 32-33 inches for the inside and 39-40 on the outside.
fife, I already had your thread bookmarked and have been going over it time and again! [swg] If you don’t mind I will be pestering you on some of the layout materials later on in the process. Linda (my better half) has already volunteered to help with making it “realistic”, so I’ve shown her the pictures that you posted. (Along with about 25 web pictures of various real viaducts.) I hope my final product at least comes within spitting distance of yours!
Spank - Fire away. Like sharing, and learning. Most of what you see on my viaduct was made with scrap pieces just layin’ around for years. The panelling was suited perfect for the odd curvatures I needed.
The Lowes in my area sells Laun plywood BUT they call it Exterior Hardboard or Import Exterior Hardboard. It’s thickness may be listed in mm instead of fractions of an inch but it is almost exactly 1/4"
Granted you Lowes may not carry this but it might be worth a try.
Good Luck
Oh FWIW I think masonite would work, and it would be WAY cheaper then the Luan / Hardboard stuff.
Just a background on my Lowes visits so far: when I first conceived this project two weeks ago I visited a Lowes near my work. They had a few things which could work, but checking their paneling section and testing different paneling and veneers I found nothing that had the flexibility I wanted other than the peg board I mentioned above. Over this past weekend I went with my two lil’ ones (who are very excited about this project, especially Tyler my 6yo) to the Lowes near my house to pick up the plywood, some jigsaw blades and a few other items. Their selection of wood was horrible - everything in 4x8 sheets, only two aisles of lumber, very little variety, just…wow, why would anyone go to this store. (Unless, of course, you needed a small appliance, laundry detergent, refrigerator packs of soda, or other household supplies.) I walked out of there with only the jigsaw blades and an incredulous disbelief that they bill themselves as a hardware store.
Last night I picked up a 4’x4’ section of 3/4" plywood and a 1"x2" for the trammel from the Lowes near work. (Unfortunately they only had yardsticks made of steel, and I didn’t feel like trying to drill holes in them.) I spent some time again in the paneling aisle and found they had 1/4" masonite which was very flexible. Last time I was here they had that slot filled with the 3/8" version which wouldn’t work. In playing with it in the aisle I found I could achieve the flixibility I wanted as is, with no required wetting or scoring. COOL! They also had some 1/4" luan plywood, but man was that stiff. That’d take a lot of work to ge
Well, I got the trammel made and used it to cut the templates out of the poster board. However, the jigsaw I borrowed isn’t as … stable as I’d like, do I need to bring my tools down before the next step, which is to cut the curves for the viaduct out of the plywood.
You asked for it! [swg]
Okay, first thing I’m curious about is how you connected the supports to the roadbed. My supports and roadbed will be cut out of the 3/4" plywood - I’m thinking that just putting screws through the plywood roadbed into the plywood supports is just not going to be strong enough. Perhaps a shim? (I don’t know if that’s the right word for it - a block of wood under the roadbed next to the support that both are screwed into) Or even one on each side?
Spank - I do most of my cutting on our picnic table out back. Keeps things level, and the sawdust out of my layout room. Don’t forget to have a piece of sandpaper on hand to quickly wisp away the rough edges.
I used the track and roadbed as my “template” (O54-O54-O72-O72-O72), traced right onto the plywood. I used the inside guide on my jigsaw to add an additional one inch on both sides of roadbed, as I cut out the contoured shape. I had a piece of old bed frame (solid hard wood) that I used for risers, spacing them evenly where the abutments would go, then a single screw from below the bench work to hold it in place, and another single screw (at this time) to secure the plywood/subroadbed on top. It will be sturdy. My benchwork sustains my 200+ frame from time to time.
I had the added headache of figuring out a 3%-ish grade at the same time…[B)] But that’s another story.
That Lowes is screwed up … luan plywood is not exterior hardboard or anything near it . Totally different … hardboard is hardboard . I can get it in 1/8 " here and it’s bucu more flexible than regular plywood . Many times it’s used as underlayment for linoleum or tile over rough floors . [?] Very smooth and softer and easier to work with . And no it’s not waterproof for outside useage … so those guys in Lowe’s are steering you in the wrong direction .
Agreed, you want the dark brown pressed hard board. Just finished my viaduct, painted and put on the layout. Used the hard board with a dish as a template, Wife’s idea and it worked! 1/2 inch plywood was the base. To cover the inside viaducts, I used cardboard from Kohl’s gift boxes… left over from Christmas… Use artist acrylics to paint…
J.Daddy, your layout’s looking very nice; love that NYC, but it’s not psotwar, is it?
I want to second Ole Timer, 1/8th luan should be readily available, for purposes he mentioned. I’ ve built my whole floor level layout using 1/8th luan over 1/2x3/4 molding. It’s easy to work with, although I haven’t tried to bend it.
The luan is easier to bend the narrower it’s cut . And as stated … I wetten it and form it … slowly … and clamp it into place until it dries . That’s how all wood is bent or formed … it’s how they used to make canes . If you wetten wood with HOT water you can keep bending it … slow process if you want to take the time . You can even take firring strips … cut them in half … thirds or quarters on a bandsaw lengthwise or smaller strips and bend those rascls more and more … let alone smaller strips for an arch ! I guess with enough time you could make a circle . [swg] Take a length of 2x4 and keep nailing or better yet dry wall screwing little strips to it in smaller lengths in between and move the project to the next smaller area . Makes a cheap form to be used over and over . Get a cheap pair of those brown gloves with a heavy pair of extra large rubber gloves over them at the dollar store to handle it though !!! The best deal is one of those bargain glueing clamps in the hardware dept . at wal mart or home depot … you can inch the length … the one with the extra long jaws .
Well, I cut out the curves last night with Tyler - they came out really nice. Thanks for the suggestions for that trammel guys - that worked brilliantly.
I also cut out the templates for my straight pieces, and now realize that I have a problem in terms of how this will layout over my temporary layout. Simply put, I had assumed I’d be able to lay out the straight sections and connect them with bridges to the curves, with the bridges giving me the clearance I need for the lower level. However, that ain’t gonna work. A picture is worth a thousand words, so I’m gonna try to upload a couple of pictures either tonight or tomorrow night so that you get a better idea of what I’m talking about. (btw: I’m also taking pictures of my progress with the pieces just to detail the steps I’m going through.) I’m glad I cut the templates and laid them out before going ahead with cutting the straight pieces!
