Derailing 2-4-2 7.5" 1.6 scale

This forum is dedicated to the Live Steam Hobbyist Community.

Moderators: cbrew, Harold_V

Post Reply
Emfinger
Posts: 229
Joined: Tue Oct 01, 2019 3:30 pm
Location: Yucca Valley, CA

Derailing 2-4-2 7.5" 1.6 scale

Post by Emfinger »

Hello, I have a 2-4-2 Columbia that likes to derail the tender, sometimes the leading axil, sometimes the trailing axil of the engine, but most often the leading truck on the tender. It seems to happen at the same spots but not always. Others don't seem to have the problem. I have serviced the trucks and don't see anything wrong but ???

Some say I should be able to lift one wheel 1/4" off the track without other wheels lifting. I can lift mine 1/2" without others lifting.

Thank you for any help
Tom Emfinger
Marty_Knox
Posts: 1724
Joined: Thu Jan 09, 2003 6:50 pm
Location: Michigan, USA

Re: Derailing 2-4-2 7.5" 1.6 scale

Post by Marty_Knox »

Check your drawbar. If it's too tight it will cause the problem you're describing.
User avatar
NP317
Posts: 4557
Joined: Tue Jun 24, 2014 2:57 pm
Location: Northern Oregon, USA

Re: Derailing 2-4-2 7.5" 1.6 scale

Post by NP317 »

I agree with Marty: Drawbar issue.
RussN
Emfinger
Posts: 229
Joined: Tue Oct 01, 2019 3:30 pm
Location: Yucca Valley, CA

Re: Derailing 2-4-2 7.5" 1.6 scale

Post by Emfinger »

Interesting, the drawbar is tight. It is made from two heim joints connected with coupler. What would you use?
Tom
ccvstmr
Posts: 2230
Joined: Sat Jan 04, 2003 10:37 am
Location: New Lenox, IL

Re: Derailing 2-4-2 7.5" 1.6 scale

Post by ccvstmr »

Em...nothing wrong with Heim/rod end ball joints. Have had such a draw bar between my loco and tender for years. Put those in to solve another issue. Question...do the balls pivot easily in their housings? Is there something else preventing the drawbar from moving enough up/down and side-to-side without obstructions?

If necessary, get down on the ground and watch what the wheel sets/trucks are doing thru the problem spot you identified. There's gotta be a reason why things are coming off the track. It's going to take some close observation to find the cause. Good luck. Tell us what you find. Carl B.
Life is like a sewer...what you get out of it depends on what you put into it!
I don't walk on water...I just learned where some of the stepping stones are!
I love mankind...it's some of the people I can't stand!
Glenn Brooks
Posts: 2930
Joined: Mon Nov 10, 2014 1:39 pm
Location: Woodinville, Washington

Re: Derailing 2-4-2 7.5" 1.6 scale

Post by Glenn Brooks »

I had a similar derailing problem with couplers. Always on curves. Usually at the same spot on curves. My issue was the coupler contacts were to tight, which pulled one of trailing car wheels up onto the rail, where it would eventually derail. When the rail ballast settled to much, that spot was prone to derailing. Both because of low rail height, and primarily, to rigid a coupler connection. I ground down my coupler arms, so they easily moved up and down when locked together. Solved the problem.

As others have mentioned, sounds like your draw bar attachment could/should be a lot looser. Also check how level your track is, at those spots were your loco derails consistently. (Both Cross wise and length wise)


Glenn
Moderator - Grand Scale Forum

Motive power : 1902 A.S.Campbell 4-4-0 American - 12 5/8" gauge, 1955 Ottaway 4-4-0 American 12" gauge

Ahaha, Retirement: the good life - drifting endlessly on a Sea of projects....
Emfinger
Posts: 229
Joined: Tue Oct 01, 2019 3:30 pm
Location: Yucca Valley, CA

Re: Derailing 2-4-2 7.5" 1.6 scale

Post by Emfinger »

Yes, I'm sure the joints are too tight, they are small, I'll check for freedom.
Thanks guys
Tom
User avatar
kcameron
Posts: 266
Joined: Wed Aug 17, 2011 4:23 pm
Location: Syracuse New York

Re: Derailing 2-4-2 7.5" 1.6 scale

Post by kcameron »

Another case I've heard of derailing was a loco where the springs didn't put the weight in balance on the rails. The pilot truck was very light on one side and heavy on the other. It did fine on the track but came off when hitting a curve in only one direction. They adjusted the springs to get the weight even and it ran fine after that.
Last edited by kcameron on Thu Nov 19, 2020 9:48 pm, edited 1 time in total.
-ken cameron
Syracuse Model Railroad Club http://www.SyracuseModelRr.org/
CNY Modelers http://www.cnymod.com/
Finger Lakes Live Steamers http://www.fingerlakeslivesteamers.org/
Member JMRI Developer Team http://www.jmri.org/
mailto: kcameron@twcny.rr.com
In the Upstate New York US area of the world
User avatar
Dick_Morris
Posts: 2842
Joined: Sat Jan 04, 2003 2:09 pm
Location: Anchorage, AK

Re: Derailing 2-4-2 7.5" 1.6 scale

Post by Dick_Morris »

The locomotive might not be the only cause. Have you checked the track in the places where you derail, particularly for changes in cross-level?
Post Reply