# Curve Question:

Discussion in 'HO Scale Model Trains' started by MCD4x4, Mar 17, 2007.

1. ### prodigy2k7Member

I said two line segments, not curves...
a Line is straight
2. ### oldtankerMember

Curves are best on women......I have some curves...kinda round....but it ain't attractive!

Rick
3. ### TriplexActive Member

But now the tail track of the switchback is difficult to use, because it's necessary to get out of the two switchback tracks. Thus, there are only four useful yard tracks.

5. ### cidchaseActive Member

As long as we're bein' so technical and all...

"parallel curves (′par·ə′lel ′kərvz)
(mathematics) Two curves such that one curve is the locus of points on the normals to the other curve at a fixed distance along the normals."

I guess " parallel curves" is OK after all, ayuh!
6. ### Russ BellinisActive Member

I think we have degenerated into picking some serious nits here!
7. ### prodigy2k7Member

a 180 degree angle from a point to another point =P

or

"without a bend, angle, or curve; not curved; direct: a straight path."
8. ### cidchaseActive Member

That's OK, Russ, yer absolutely right, but it's fun!
9. ### YmeBPMember

Picking nits is better than picking n.. well you know hahah
10. ### Ten WheelerNew Member

Disregarding the nit picking of mathmatical statements and poor spelling I would like to ask MCDC4X4 a question on his pro[posed track plan. If you decide to follow the instructions as presented by a couple of people that knew their guage's deminsions, I notice that your plan has provisions for ramping fromone level to another. If the engine is pulling the consign up the ramp to the next level, does it have to push it back down the ramp in order to get back down? I did not see provisions for revese looping in order to change directions.
11. ### MCD4x4Member

Ya, I guess it going to have to push the three non motored cars down. I'm lucky I can pull this off. I sure don't have room for another ramp. I think all will work out fine. I'll save this link and post some pictures as I go. I want to cut the yard switches and shorten them up so I can fit in more lay ups on the left side. I've do this with O scale. I'd like to leave the right side open for some scenery.

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12. ### green_elite_cabKeep It Moving!

subways run on push pull anyway, right?
13. ### MCD4x4Member

Yeah, all the cars are the same, and they are all motorize. I think all this will work out fine.

.:thumb:
14. ### jetrockMember

Indeed, I think a few people are missing that MCD4x4 is building a subway layout, not a steam/diesel layout, which means that he doesn't have to worry about pulling long trains, and he doesn't have conventional passenger-layout worries about 80-foot cars on sharp curves.

In fact, it might be worthwhile to build a test track from flextrack to find out what radius these cars can reliably handle. Electric interurban layouts with good trackwork can have curve radii as sharp as 8-10", although that's probably pushing it for an articulated subway set. 15" is pretty darn comfortable for traction and 18" is downright broad, as long as you keep in mind clearance between the tracks.
15. ### green_elite_cabKeep It Moving!

He did mention wanting to run an ALP44 with NJ tranist commuter cars a while back.
16. ### MCD4x4Member

The cars are 6 3/4 long. If I can run that jersey set or teh LIRR set on the lower outside line thats cool, if not, I'll have to get over it. My main concern is the subways.

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17. ### jetrockMember

The length of the cars doesn't always gauge how sharp of curves they can manage--that depends more on mechanism and wheel clearance. Although the fact that they're only 6-3/4" long is a good hint that they don't demand broad curves.
18. ### MCD4x4Member

Would the NJT and the LIRR trains run on the 18's?

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19. ### Russ BellinisActive Member

I think they should handle 18 inch radius. Most 4 axle short wheelbase diesels without a lot of overhang will handle 15 inch radius even. The only 4 axle diesel that I'm not sure of is the Dash8-40B GE models. They are kind of long for a 4 axle diesel.

As far as pushing the trains back down the ramp, it shouldn't be much of a problem. You may have some difficulties with derailing at the bottom which should be curable with extra weight added to the cars. For pushing the train back down, the weight of the cars + gravity should cause them to go down ok once they are started rolling with the initial push. The locomotive will probably hold them back. It won't be a problem until you start pushing them through curves on the lower level. You can certainly check for their operation by pushing them on the upper level through curving track and switches to see if the cars track ok without derailing. The main thing is to take extreme care to make sure that your track work is flawless on the lower level especially. No bumps at rail joints, no dips, no kinks, & no gaps between rails.
20. ### MCD4x4Member

If you look at the pictures of the slot car layout above, you will notice train track rises 2 1/4 inches within 27 inches and curves. All made of flex track. I ran the subways and one freight train, UP engine with four cars. Once I worked out the kinks, both types of trains ran fine in both directions. So I'm thinking a three inch climb streached out over eight feet will be a breeze.eres a video of the train running ane the bridge opening.

http://www.mcd4x4.com/trains/ho_bridge.MOV