|
|
 Posted - July 07 2009 : 6:33:44 PM
|
I dropped an old PRR F7A shell on to a powered chassis I pulled out of the back of a draw & was surprised to find that at the 1st curve it kept going straight off the rails.
Closer inspection revealed that the front & innermost rear side ladders on the shell were fouling brake cylinders on the trucks. The old chassis that I took the PRR shell off does not have molded brake cylinders on the trucks.
So I am scratching my head trying to figure out if there are F7A shells that work with the 'brake cylindered' trucks, or whether the fix is to cut off the offending cylinders.
The extent of the restriction on turning can be seen in the 2 shots below that show the trucks turned to nearly full extent, with & without the shell fitted. There is also a close up showing the brake cylinder & ladder rubbing on the back truck.
Any thoughts??
Tanked
|
Country:  USA ~
Posts: 243 ~
Member Since: September 08 2008 ~
Last Visit: January 04 2012
|
Alert Moderator
|
|
|
|
Posted - July 07 2009 : 7:43:59 PM
|
How tight are the curves you're running on? I've noted the tight clearances on some F-unit models myself, but have never had trouble running them on 18" curves.
As for said clearances: Your shell appears to already have fairly thin ladders, so there's not much you can do there. If the trucks are newer (plastic) Athearn, you should be able to remove the brake cylinders completely - just pull them out (they may be glued in). Or are they not pushed in all the way to begin with (check that first)? Alternatively you could cut the actuating rods off the cylinder assembly.
Tyco's F was one of the worst for tight clearances, the earlier MU-2 versions had barely a hair's width to spare. Eventually they even removed the front steps from the shell to address this, rather than retool the trucks (admittedly this was a short-lived tactic, quickly rectified with new trucks and eventually an all-new shell).
|
|
Country: USA ~
Posts: 2175 ~
Member Since: July 15 2006 ~
Last Visit: January 31 2010
|
Alert Moderator
|
|
|
|
Posted - July 07 2009 : 8:00:23 PM
|
I've noticed the same thing on Athearn F units. If you snip the piston and brake actuation lever off the interfering cylinders, they will clear on 18" radius curves, and it won't be easily noticeable.
The Tyco Depot
|
|
Country: USA ~
Posts: 3927 ~
Member Since: June 20 2007 ~
Last Visit: November 19 2015
|
Alert Moderator
|
|
|
|
Posted - July 10 2009 : 3:09:18 PM
|
quote:I've noticed the same thing on Athearn F units. If you snip the piston and brake actuation lever off the interfering cylinders, they will clear on 18" radius curves, and it won't be easily noticeable.
Originally posted by NickelPlate759-July 07 2009: 8:00:23 PM
|
Tried that & it works well.
Tanked
|
|
Country: USA ~
Posts: 243 ~
Member Since: September 08 2008 ~
Last Visit: January 04 2012
|
Alert Moderator
|
|
Home
Forums
Events Calendar
Forum Admins & Mods
Register
