Converting an O scale drawing to HO scale

[Anonymous]

Hello,

I am looking for help or suggestions on how to convert o scale to ho. I was recently reading an issue of Classic Toy Trains from 2/01 and it had a rather nice layout that I would like to do in HO. I've read about placing the drawing on a copier at 55% but I don't quite understand what that would accomplish. The picture appears to be scaled at 1"=2' with the layout being 12'6" x 14'6".

What is "scale down or up" ratio to convert to HO? or is there even such a thing?

Thanks

Ross

[Anonymous]

Dear ross182,
The easiest way to convert these drawings in my mind would be to photocopy the O scale drawing at 48/87, which is also 0.55172413793103448275862068965517, or 55.172413793103448275862068965517%. Of course, for all practical purposes, 55.1724% would probably be more than adequate.

To convert the drawings from HO to O, just photocopy it at 87/48, which is also 1.8125, or 181.25%.

I hope I have helped,
Daniel

[Hudsonmike]

Hey Ross;
If you were doing a car, engine or building than you would scale down the drawing.
as Daniel is pointing out and is the correct answer.
But this is a layout which is really a blue print, the drawing in question is 1 inch =
equals 2 feet which is 6"3 which is 12'6" by 7"3 which is 14' 6"
seeing that HO is 1/2 of O scale Your lay out would be 6'3" by 7'3" and you should be
able to fit every thing in your lay out that is in the O scale layout.
The drawing has nothing to do with O scale the scale of the drawing is its own
scale which you can convert to any math scale you want most blue prints ( like for Houses)are 1/4 inch to the foot . So if you want a better drawing Increase the drawing by 50% and use one Inch to the foot instead of one inch to two feet.
I hope you can under stand this
Mike

[IRONROOSTER]

Drawings are usually scaled to enable one to have a full sized template. Say you have drawings for a station. If they are O scale you take measurements directly from the drawing and or lay the parts directly on the drawing during construction. To use the drawing in another scale you copy it either enlarging or shrinking as appropriate. For HO this would be 48/87 or 55%.

For a layout drawing there is no need to copy it (it's not full size any way). Instead you treat the layout drawing as being to a different scale. Instead of 1"=2' you treat it as 1"=1'. Your layout drawing now represents a layout of 6'3" x 7'3" . Grade separations and radii are also reduced to half. Note this is a convience over using 55% and getting awkard dimensions - necessary for a model but for a layout not as crticial.

However, you may have a problem using it in HO. Most toy train layouts use very sharp curves. O27 is 27" diameter or 13.5" radius. O31 is 31" diameter or 15.5" radius. These are already too sharp for HO. Only very short cars and engines will operate on curves this sharp. Cut them in half and only a 4 wheel trolley will operate. Use the toy train layout as inspiration and draw up layout plans using a radius that your HO trains will run on.

Good luck
Paul

[dehusman]

There are a couple things you have to watch when scaling up or down trackplans. They can't be scaled exactly as a plan for a boxcar can.
The most important is that trackplans are designed to accomodate people. This is especially critical when you are scaling down a plan (O to HO, HO to N, etc). If there is an access area or an aisle on an O scale layout that's 2 ft wide and you cut it in half to make the plan HO, that aisle is now about 1 ft wide. A 2 ft aisle will easily accomodate one person. A one foot aisle will not accomodate most adults. So you may have to add extra space in a plan to accomodate the operators.
The track components may not have the same geometry from one scale to another. An O scale tinplate switch doesn't have the same angles and comparative length as an HO switch. So if you convert it from O to HO it may not work out the same because the switches, radii, track centers, etc will be different.

Dave H.

[Anonymous]

Thanks for your help. AT least I know what the overall dimensions wil be in HO. I am experimenting with the Atlas Right Track program so this will be helpful. Any other suggestions from other are certainly welcome. Thanks again.

Ross