Help in Drafting!

[Anonymous]

Hello, everyone at Trains.com! Okay, so I'm 16 and sitting in Drafting class in school*blah*[xx(]! So, anyway I came up with this cool idea of drawing an HO scale railway table, but then I got stumped! I had no clue what kind on dimensions were in an HO table! So, I was wondering if anyone knew some accurate dimensions for an HO roundhouse and/or turntable!
Thanx!

[Anonymous]

Are you talking about drawing a layout (i.e. all the "model" parts, usually on top of the table) or benchwork (the table itself)?

If you want to design a layout, there is a ton of information on the internet, beginning with the parent site of this forum - trains.com - and Model Railroader. As for dimensions of things like roundhouses and turntables - they were all different sizes. Turntables from ~75 feet to over 130 feet long. Roundhouses had anywhere from two to 20 or more stalls. You can get some basic sizes by looking at the model sizes and converting back to "real" feet. The Walthers catalog on-line (www.walthers.com) often lists the models' basic dimensions in the description.

For more detail, I would suggest looking for Kalmbach (Model Railroader) books such as "Lineside structures you can build" as they have examples of scale drawings.

There are also books and internet sites dedicated to building benchwork - a whole subproject so to speak - for your model railroad. Some of this might make for interesting drafting project(s).

Good luck!

Andrew

[Anonymous]

Well, I guess the whole table in general! At first, I just wanted the roundhouse/ turntable dimensions, and I'll stick with that! Plus, I am kind of confused on what you're asking!

[Anonymous]

Oh, I get it! I am drawing the whole layout (including the table, tracks, mountains, etc...)

[Anonymous]

Wow - ok. That is a huge undertaking. Some guys spend years planning a layout to get it just right!

You might want to start with only a module - a standard 2 foot by 4 foot "table" that a number of modellers use. Also it will limit the number of structures you have to draw. In HO scale, you can really only fit a small roundhouse, or part of a larger one, on this amount of table. If you focussed on an engine servicing facility in the steam era, you could fill your 2x4 table with a small roundhouse, a coal tower, a water tower, ash pit, a couple of small outbuildings, and it'd be full. For an interesting example, see:

http://www.geocities.com/fundynorthern/FirstModules.html

Bob's modules are sightly larger than 2x4, and they are designed in pairs, but you get the idea.

Here's a link to building modules, so you can se how a standard 2x4 is put together:

http://www.railwaybob.com/Modules/ModuleConstruction/ModConstr01.htm

I don't know if you do your drafting on the computer. It has been a while since I was in drafting class, but we used to do our drawings with pencils and paper... wow, I sound old [;)]

You could start with Atlas Right Track Software (RTS). It is available at www.atlasrr.com . That will let you play around with track, and the basic footprint of a variety of buildings to get a feel for things.

Anyway, this is a big challenge, so I hope it works out for you. If you have any other questions - post away!

Andrew

[Anonymous]

Thanks a bunch for the help! Now I know that my 'table' was the wrong size! Yeah, we do the drafting on computers, guess you're showing you're age! Just kidding!
Thanks,

[RhB_HJ]

QUOTE: Originally posted by c00kiem0nster

Thanks a bunch for the help! Now I know that my 'table' was the wrong size! Yeah, we do the drafting on computers, guess you're showing you're age! Just kidding!
Thanks,

Hey Cookie (Smart Cookie??[:0])

If, by chance, you're interested in CAD programs that are designed for layout planning have a look at
http://sandiasoftware.com/ and http://www.trackplanning.com/3pi.htm
you can download a demo version at either location.

BTW rather than use a fixed table size you should have the teacher give you the dimensions of the room, then you design the layout to make the best use of the space.

At least that's how I do it (I design layouts for customers), this despite showing my age (I've got plenty of grey hair, wear bi-focals and have a few wrinkles)[;)][;)][:o)][:)]

[Anonymous]

A roundhouse and turntable is actually a very good little geometric puzzle for a high school drafting class. The length of the turntable would vary, as railroads only wanted a turntable long enough to turn the longest locomotives that would be assigned there, and the longest locomotive might have grown larger in the years after the turntable was built (such as when articulated steam locomotives became popular). I don't know whether turntable pits were enlarged over time, but I bet that some were.

Anyways, the optimum length of the turntable bridge is just a little bit longer than the longest locomotive. Then, the optimum track spacing around the pit comes into play. You'd think that the tracks would just be placed at some regular angular interval, such as every 10 degrees, but really what was critical was the spacing of the tracks at the point that they enter the roundhouse, such that there is enough space between track centers to fit the doors, their hinges, and the structural column(s). Inside the roundhouse, the space between tracks opens up, creating workspace. If the angle between tracks is too great, then too much workspace is created, in other words space is wasted. If the angle is too small, then either there will be too little workspace, or the roundhouse will have to sit back away from the pit by a good distance.

Use circles of varying diameter to lay it all out; once you get the right angular spacing, you can just copy the first track into a rotated array (I don't know what sort of CAD software you're using). The first circle is obviously the pit, at whatever diameter you've chosen. The next circle gets placed such that its center is on the rim of the pit. This circle would have a diameter of five feet, which is approximately the distance from the outside edge of one rail to the outside edge of the other (inside gauge is 4'-8 1/2"). Do another 5' circle centered on the intersection of the rim and the first 5' circle, and then where the second 5' circle intersects the rim will be the centerlines of the two adjacent tracks; the centerline of any track will radiate out perpendicular to the rim. By marching the 5' circle around the rim, you can place all your stall track centerlines. Incidentally, this is how we old fogies would do it using compasses instead of computers.

To figure out where the front of the roundhouse is, you need to figure out how wide a typical stall doorway will be. You know you need clearance for the engine itself, which would ordinarily be about 16 feet wide. I don't know if roundhouse stall doors were tighter than this; they might have been, since any locomotive would be less than 11 feet wide. To this opening width, you need to add the actual widths of the door panels, since when they are open they will be parallel to the track, and then you need to add enough width for the structural supports inside. Guessing that the doors might each be 4 inches wide, and that the required structural width comes to around 16 inches, you come up with an additional 24 inches (2 feet), so that a typical stall width works out to 18 feet.

Since you have track centerlines laid out, pick two adjacent ones, and offset (create a parallel line) one line that is 9 feet from each centerline. Where these two offset lines intersect, the width between the adjacent tracks is exactly 18 feet; the front of the roundhouse would have to be here or somewhere beyond this point. The roundhouse itself should be a bit deeper than the turntable bridge length (the rim diameter), at least in some of the stalls, so that the entire locomotive can fit inside. Sometimes roundhouses have varying stall depths, with a few shorter stalls just fit into a tight situation.

Hope this helps, and I hope you have fun with the project!

[Anonymous]

Thank you to everyone! I may need more help on this so stay in touch!

[Anonymous]

Do any of you happen to know the dimensions of a sawhorse?

[Anonymous]

Pick a size!

Saw horses are like turntables - they are as big as the person who built it thought they would need.

I'd guess about a metre high and 1.5m wide - the spread of the legs looks about 30 degrees on average.

maybe you should have taken woodwork as well [:)]

[Anonymous]

Would you say that there would be 2 or 4 saw horses on a 4'X6' table? By the way, thanks again for all the help!

[Anonymous]

If you are putting your layout on saw horses, instead of built-in legs, you would probably only have two saw horses for a 4x6. They would be 4 feet wide, and the crossbar would contact the underside of the table about 1 foot in from each end of the table.

It would probably be easier to put 4 legs on the layout, both in real life, and in the drawing... I would again point you to "railway bob's" excellent how-to:

http://www.railwaybob.com/Modules/ModuleConstruction/ModConstr01.htm - If you go "up" one level (click on "Index" at the top of the page), you will find two links to building legs - one from wood (click on "Legs"), and one from ABS plumbing (click "ABS").

Andrew

[Anonymous]

WOW! You are so helpful! Thanks! Stay in touch! I am probably going to need a lot more help!!!

[Anonymous]

At it's maximum (according to using walthers roundhouse and turntable for modern equipment), the 130' turn table is 20" in diameter, it would have 1 15/16" distance between the turntable and the roundhouse, the roundhouse is 20 1/8" in length. so any single section would be 32 1/16" in radius.

So taking those dimensions, you would need 64 1/8" to show a full roundhouse and turntable. Walther's uses 10 degree's between stalls of the roundhouse, so you should stick to that as a minimum when using this arangement.


and there you go,
Jay.

[Anonymous]

Corkboard! Does anyone know anything about corkboard? Also, is there a set value for a turning radius on turns? How wide is it?[?]

[Anonymous]

Hi Cookie,

How's that plan coming along? Any chance of seeing a picture of your drafting? If you can put it up somewhere on the web as a jpg, post a link!

Anyway, to answer the question about radii: On a 4x8 layout, the biggest radius you can have for a return loop (i.e. end up going in the opposite direction) is about 22". That makes a circle of diameter 44", leaving a little space on either side. Minimum that most people would recommend is 18" radius. However, if you have a specific theme for your layout, you may go smaller - e.g. "traction" or streetcars - they can operate on much tighter radii than normal - in HO scale they could be as small as 10 - 12" radius. You can alos have curves with bigger radii, but of course, you will not be able to fit a whole circle (or even a 1/2 circle) on the 4x8 table.

HO cork is about 1/4" thick, and about 2 inches wide. It can be used to represent well-maintained, high-profile ballast that you might see on a main line. Some railroads did not use, or did not maintain, their roadbeds very well, so over time, it would look as if they had none, or that the track was just running on a grassy raised area.

For more info on this and other aspects of building/designing a layout, look at Model Railroader's "how-to" articles here:

http://www.trains.com/Content/Dynamic/Articles/000/000/004/474duagg.asp

Andrew

[Anonymous]

I have posted, for anyone who wants to see it, a picture of what I have finished so far! Click here--> http://pub13.bravenet.com/photocenter/viewimg.php?usernum=1086553614&show=1CBB931271.jpg Not much to look at so far! Oh, and I edited the mountain after I put this picture up![:D]

[Anonymous]

How wide is HO track? I need to know that before I can start on the corkboard!

[Anonymous]

Try the link above for some general info on building layouts, and this link:

http://www.trains.com/Content/Dynamic/Articles/000/000/001/296zmshd.asp

for specifics on HO scale items, including track width. The height of the rail is in the "code" that you choose: cose 100 is 100/1000ths high (i.e. 1/10 of an inch). Ties may vary in thickness, but it is safe to assume that the ties are not as high as the rails - in real life, they may be 6" high by 9" wide.

I like the table so far - will you add bracing to the legs?

Andrew

[Anonymous]

Well, is there a set code? Or, what would you reccomend?

[Anonymous]

Well, there is a "set" code - determined by what is available. Most common is Code 100 and Code 83 (0.100" and 0.083" high rails respectively). Most modellers choose either Code 100 or 83, with 83 taking more and more of the market all the time. Modellers who want "cloer to scale" will chose Code 83, or even Code 70 or Code 55. The lighter codes represent lighter rail, more common on "older" layouts and branchlines or siding. Heavy rail is/was reserved for mainlines.

For the purposes of making your drafting easier, I would choose Code 100, simply because 1/10" is easier to understand...? If there are no technical challenges with the drafting software, I would go with Code 83.

Andrew

[Anonymous]

Update on the drawing--> http://photos.bravenet.com/108/655/361/4/F87E698C3B.jpg

[Anonymous]

Link to your drawing did not work this time. This is the text of the error message:

"Sorry, the image you are trying to connect to cannot be load.

We do not allow remote linking to files stored on servers in our network."

Andrew

[Anonymous]

Sorry, I'm not used to Bravenet! I'll have it up soon!

[Anonymous]

Her is my website! The pictures are on the 'My Pictures' part of the photo album!
--> http://c00kiem0nster.bravehost.com/index.html

[Anonymous]

Man Cookie, I don't know how you work like that. If I were you, I would turn off a few of the tool bars you have set up there, and expand the viewing area of your drawing. Im an old cad jockey, and I have gotten to the point that I have to have two monitors to be real productive.

It looks like your drawing is coming along! Keep it up.
--C. Alan

[Anonymous]

If I turned off one toolbar, then I'd actually need it! So I just leave them up!

[Anonymous]

So, I'm not getting the whole thing with code 83... what is a width/heigth?

[Anonymous]

The second and third paragraphs of this article: http://www.trains.com/Content/Dynamic/Articles/000/000/001/296zmshd.asp explain HO track very well. Just remember that everything in HO scale is 1/87th the size. Therefore something that is 87 feet long in real life is represented by a 1 foot long model. My 4-6-2 steam engine for example. The model is just under 1 foot long. That means that the real thing was just under 87 feet long.

If you want to get specific with the rail dimensions, look here:

http://www.trains.com/Content/Dynamic/Articles/000/000/000/347ybfns.asp

Andrew