Freerails Home 
Home Search search Menu menu Not logged in - Login | Register
Freerails > Model Railroad Forums > Track Planning > How To Measure Radius & Other Questions

Freerails is accepting new Members ... To join Freerails ... See how to Register as a Member in the 'Joining Freerails' Forum

How To Measure Radius & Other Questions
 Moderated by: Herb Kephart Page:    1  2  Next Page Last Page  
New Topic Reply Printer Friendly
 Rating:  Rating
AuthorPost
 Posted: Sun Nov 13th, 2011 01:41 pm
  PMQuoteReply
1st Post
ssculptor
Registered


Joined: Thu Mar 5th, 2009
Location: Connecticut USA
Posts: 41
Status: 
Offline
I need to make a full 20 foot diameter circle of track so I can run articulated locos in G gauge and have them look OK. I have lots of straight track as well curved track I accumulated over the years for this project.
My first question is how do I measure the radius of a curve. From the outside of the inside rail, from the center line between the rails, from where? L:
Second, to save money I'd like to use the rail I have. Has anyone tried straightening pre-curved rail and then curving it back to the larger radius?:brill:
Any helpful hints will be greatly appreciated. 
Thanks,
Stephen



____________________
"I am not a grouch. It is just that I am right and everybody else is wrong."
J. Pierpont Feathersbottom, Esq.
Back To Top

 Posted: Sun Nov 13th, 2011 01:56 pm
  PMQuoteReply
2nd Post
pipopak
Moderator


Joined: Wed Apr 13th, 2011
Location: Florida USA
Posts: 1790
Status: 
Offline
ssculptor wrote: I need to make a full 20 foot diameter circle of track so I can run articulated locos in G gauge and have them look OK. I have lots of straight track as well curved track I accumulated over the years for this project.
My first question is how do I measure the radius of a curve. From the outside of the inside rail, from the center line between the rails, from where? L:
Second, to save money I'd like to use the rail I have. Has anyone tried straightening pre-curved rail and then curving it back to the larger radius?:brill:
Any helpful hints will be greatly appreciated. 
Thanks,
Stephen
Measure from the center of the track.
About re-curving track, depends on a lot of variables. I'd say cut and remove the plastic pieces that go from one tie to the next under the rail and try to straighten it as needed. Do one first as a test mule.



____________________
Junk is something you throw away three weeks before you need it.
Back To Top

 Posted: Sun Nov 13th, 2011 08:44 pm
  PMQuoteReply
3rd Post
Herb Kephart
Moderator


Joined: Thu Jul 19th, 2007
Location: Glen Mills, Pennsylvania USA
Posts: 6114
Status: 
Offline
pipopak wrote:
Measure from the center of the track.

Although when you are talking about 20 ft. radius-----does it really matter?

Herb 



____________________
Fix it again, Mr Gates--it still works!"
Back To Top

 Posted: Sun Nov 13th, 2011 09:10 pm
  PMQuoteReply
4th Post
ssculptor
Registered


Joined: Thu Mar 5th, 2009
Location: Connecticut USA
Posts: 41
Status: 
Offline
Well, it is a 20 foot diameter, not radius. Also I want a smooth curve, I hate it when I see a train negotiating a curve that was made up with a bunch of mismatched curved pieces and straights. I just want to avoid the jerky movements. I am trying for good track. The narrow gauge portion (60cm WW1 trains) will be jerky. I have some 60 inch lengths of flextrack in G that I may use for the curve, but I'd rather use that for slightly curved sections along the main line.
Yes, I understand that it really does not matter much if I am off a few inches when we are talking about a 120 inch radius. But I' d like to have a place to start. Basically this outdoor layout will be a sort of dogbone or maybe elongated oval about 50 to 75 feet long. It will be built on 36 inch high modules, each being about 5 feet long and more or less interchangeable.
Stephen



____________________
"I am not a grouch. It is just that I am right and everybody else is wrong."
J. Pierpont Feathersbottom, Esq.
Back To Top

 Posted: Tue Dec 13th, 2011 12:46 pm
  PMQuoteReply
5th Post
bobh
Registered
 

Joined: Thu Jun 30th, 2011
Location:  
Posts: 69
Status: 
Offline
So its a 10Ft. radius. No problem making a smooth curve. You will need a pattern to follow. I would suggest making a wooden (ply maybe) pattern that can be placed along the inside of the curve. You can then push the flex track against it and fasten it down.

Back To Top

 Posted: Tue Dec 13th, 2011 01:10 pm
  PMQuoteReply
6th Post
ssculptor
Registered


Joined: Thu Mar 5th, 2009
Location: Connecticut USA
Posts: 41
Status: 
Offline
I do not want to use my flex track for that. I want to use up a lot of my short curves of different radii and straight pieces. I guess that what you propose is the best way to do it. Cut the inner radius out of cheap plywood, lay it out and then fit the flex track.
Or, if I want to use the smaller radii curved pieces I already have I'll just try to bend the track to match the curves. Maybe the best way is to use my own wood ties, spike them down and then straighten the curved pieces a bit to get the wider radius. I suppose that I could always cut a couple cylindrical bar with the shape of the rail in them, space them in a fixture and then run the rails through them to change the curve. Or just buy or borrow the device that is made for that to reshape the curves to 20 foot diameter.
Or just follow your advice and use my flex track. Sure would be easier and quicker.
Thanks, Stephen



____________________
"I am not a grouch. It is just that I am right and everybody else is wrong."
J. Pierpont Feathersbottom, Esq.
Back To Top

 Posted: Thu Dec 15th, 2011 04:01 pm
  PMQuoteReply
7th Post
W C Greene
Moderator


Joined: Fri May 4th, 2007
Location: Royse City, Texas USA
Posts: 7679
Status: 
Offline
The old "devil's advocate" might suggest to get ahold of some stock rail (Micro Engineering), nice pine or redwood ties, spikes, and get to work. Less time spent thinking and more time having fun. You didn't mention-is this outside or inside?
Woodie



____________________
It doesn't matter if you win or lose, its' how you rig the game.
Back To Top

 Posted: Thu Dec 15th, 2011 05:57 pm
  PMQuoteReply
8th Post
ssculptor
Registered


Joined: Thu Mar 5th, 2009
Location: Connecticut USA
Posts: 41
Status: 
Offline
One of the parameters of making my outdoor layout is that I have no intention of spending any more money for materials I already have in stock. Yes it would be easier to buy fresh rail but if I am going to spend money why not just buy a 20' diameter of new track?
No, I will do this the cheap way. It is issue of pride. I started making models during the war (WW2) and we had almost nothing available back then. That is the way I am continuing with my G railroad. So I invest sweat equity. No problem.
Thanks,
Stephen:old dude:



____________________
"I am not a grouch. It is just that I am right and everybody else is wrong."
J. Pierpont Feathersbottom, Esq.
Back To Top

 Posted: Thu Dec 15th, 2011 08:43 pm
  PMQuoteReply
9th Post
Herb Kephart
Moderator


Joined: Thu Jul 19th, 2007
Location: Glen Mills, Pennsylvania USA
Posts: 6114
Status: 
Offline
To answer the origional question as to where the radius is measured, I sjust read that the British developed standards for portable track for mining, peat bog, sugar cane railroads and the like.

They defined the radius as being measured to the inside (flange side) of the outside rail.


Herb 



____________________
Fix it again, Mr Gates--it still works!"
Back To Top

 Posted: Sun Dec 18th, 2011 12:24 pm
  PMQuoteReply
10th Post
B&O GLENNWOOD
Registered


Joined: Wed Aug 25th, 2010
Location: Pittsburgh, Pennsylvania USA
Posts: 91
Status: 
Offline
My concern with using short rail sections on a curve is the number of rail joints That can be a nightmare to align I would use flex on the curves and use the short pieces on straight sections

Back To Top


 Current time is 11:37 am
Page:    1  2  Next Page Last Page  

Freerails > Model Railroad Forums > Track Planning > How To Measure Radius & Other Questions
Top



UltraBB 1.172 Copyright © 2007-2016 Data 1 Systems