PDA

View Full Version : Piggyback tracks


rkilgore
06-18-2009, 07:54 AM
I am new to model trains but have acquired lots of locos in O and HO. I am space challenged. I built a 4' x 8' train table and would like to run the HO track above the O track via a scratch built trestle system. Could anyone give an idea of how to do this or offer a pattern?

tankist
06-18-2009, 09:29 AM
hmmm, i have an idea how i would have approached this. are you looking to completley mirror the layout underneath?

rkilgore
06-18-2009, 09:33 AM
Yes, the track is a simple oval shape.

tworail
06-18-2009, 09:53 AM
Shaygetz is your man to talk to. He has done this with different types of HO track but the same principles would apply. Check out this pictures in the gallery. I'm sure he will chime in as well :)

tankist
06-18-2009, 10:01 AM
i haven't looked at standart curvature radii of non HO track but i assume that even if there is no exact radius available flexi can always be used to mirror (gosh, whoever invented flexi should be given a medal).

i would start by making planks and curved planks out of 1/2 sandwich board (or maybe even 1/4 if supports are close enough) to exactly cover your existing layout. for the supports, gosh where should i start, there are so many nice ways to create sports and decorate the viaduct.

that said i havent touched moddeling for, sheeesh, 18 years now and just getting back. so what others said :)

T-Man
06-19-2009, 07:03 AM
Sometime, I am going to place an HO loop next to the O. Just call it narow gage.:D

For a base support one article in Model RR used a backside of molding. This is fine for straights. Curves would have to be made.

If you have 360 degree access, place a backdrop down the center.
Support the HO on a tighter loop than O, make a mountain, bridge, or trestle bridge.
Figure 8 the O into the mountain.

To keep your original idea expand the backdrop to a circle for the inside of the loop and keep it solid for support. Have the outer side for decor.

Just a couple of ideas.

rkilgore
06-19-2009, 09:31 AM
Thanks for your replies. I have seen trestles built with small birch wood pieces. The vertical pieces are configured to allow HO to fit on top and joined by horizontal pieces for stability. On the vertical piece look like this:

HO here
/______\
/ | | \
/ | | \
/ __| __ | __\
/ | | \
/ | | \
O Gauge here

Notice that the two horizontal pieces in the middle obstructs the O Gauge. I just need a pattern that will allow room for the O Gauge. I think I just answered my own question. I need to built a template like this one with room underneath that has no vertical continued. I will have to experiment with some scrap wood.

Thank you all for your input!

rkilgore
06-19-2009, 09:33 AM
The ascii diagram I drew came out wrong when I last posted. The system took out all the leading spaces.

tankist
06-19-2009, 09:46 AM
i think i got what you tried to do,
but draw a quikie in MS-paint and attach :)

how about metal rod supports for the structure (painted to be wood) and wooden just for decoration? will allow you to go without that horizontal piece where needed

T-Man
06-19-2009, 11:57 AM
So you want a true trestle oval. Be sure to leave plenty of room at the corners. The O gage loves to swing out and the long cars swing in. It is going to have to be wide. It wouldn't surprise me if you had room for two HO ovals on top.

rkilgore
06-19-2009, 12:54 PM
Here is a little diagram in a jpg attachment. I love this site!

rkilgore
06-19-2009, 12:57 PM
I didn't see an attachment on my last reply. I will try it again.

tankist
06-19-2009, 01:07 PM
i'd think that if everything is built rigid enough it could work as you pictured. only the to outside beams can be made to be load bearing, the rest is decoration. again, there are so many ways i can see this being accomplished

one thing though. from what i see on trestles they are made quite dense. if you go for authenticity, will you have access to lower train if needed? i'd probably would go for "n" supports instead of true trestle if your scenery allows it.


http://upload.wikimedia.org/wikipedia/commons/thumb/1/11/Chicago-Loop-SEcorner.jpg/800px-Chicago-Loop-SEcorner.jpg

rkilgore
06-19-2009, 02:04 PM
What is an N support?

tankist
06-19-2009, 02:14 PM
not "N" but "n". perhaps i'm using bad, self invented terminology.
i meant support with 2 comletley vertical pillars suporting a beam ,
forming a:
__
| |

basicaly just like el train in chicago (pic). the streets beneath are way wider then track on top.

just an idea:)