Bridge Questions

[Puddington]

I am planning to use a Kato steel trestle to cross some interchange tracks below; I have a couple of questions....(you guys are going to get sick of me...)

1. What is the prortypical regulations for minimum head space clearance for railway bridges that cross another line - I model the early 70's so this would have been built in th5 late 50's.... clearance from rail head to bottom of the steel supports.

2. Someone here modified the Kato unitrack bridge for Atlas Code 55 - I seem to remeber a thread or weekend update that featured this - anyone have any ideas.....

Thanks in advance.....Puddy in Peterpatch 

[davefoxx]

Puddy,

Assuming that you mean the Kato truss bridge, I can help with that question.  You will need to get the top of the bridge off to really be able to get at the superstructure where the Kato track is located.  From the bottom of the bridge, you will see some slots where the top clips in.  You will not be able to release those clips without slipping an Xacto blade in the slot.  Be careful, because the knife blade can come through the side of the girder.  Once you have all of the clips free, the top pops right off.  Now you can get that code 80 track off and use a large file to take down the clips that held that track in place.

I painted my bridge before reassembly, avoiding where I would glue the code 55 track down.  I super glued Micro Engineering code 55 bridge track in place, and what an improvement to the look of the bridge!  Oh, and get rid of the Kato abutments, well, part of them anyway.  I cut the bridge shoes out of the Kato abutments and glued those to the bridge.  Place it on your abutment of choice, and...



Hope this helps,
DFF

[Puddington]

I think Kato glued mine together Dave.....seriously, the clips will not budge.... what am I missing...grrrr......

[davefoxx]

I think Kato glued mine together Dave.....seriously, the clips will not budge.... what am I missing...grrrr......

They will feel like they're welded, but, if you get in there with a knife blade, they will come free.  Push the blade in and then start tugging.  Once you get the feel for it, the rest should be easier.

[Scottl]

If you don't have the bridge yet, I have a built up Central Valley that could be sent down the road...  No use on my layout.  Code 55 is no problem with it.

[davefoxx]

If you don't have the bridge yet, I have a built up Central Valley that could be sent down the road...  No use on my layout.  Code 55 is no problem with it.

...and it's a much nicer bridge than the Kato.

[Puddington]

I like the Central Valley bridge and have two I will use. The Kato is very similar to a bridge the CPR used in Kamloops so it fits the area........back to tugging on this damn Kato.....grrrrrrrrrrrrrrrr.............

[davefoxx]

You probably don't have the blade in far enough, Puddy.  You cannot pry it free.  By pushing the blade in you are actually allowing the tab slip past the groove that holds it.  In other words, the blade is getting between the tab and the groove, so it can release.

[cv_acr]

1. What is the prortypical regulations for minimum head space clearance for railway bridges that cross another line - I model the early 70's so this would have been built in th5 late 50's.... clearance from rail head to bottom of the steel supports.

AAR clearance plate diagrams. Or use your NMRA gauge for maximum clearances.

For some reason this site doesn't have a copy of a Plate C diagram:
http://www.trainweb.org/utahrails/drgw/plate.html

Plate B and C are the most common. (Anything up to a 10'6" I.H., 50'6" I.L. car is plate B. 11' I.H. makes it a plate C car.)

Excess height boxcars are plate E or F. Loaded double stack container cars are Plate H. There is no Plate A, D or G.

[unittrain]

I believe it was like 20' min. clearance of course now with double stacks I think it is 21'.

[Frisco Larry]

the minimum for highway bridges over tracks is 23' and 27' for electrified lines.

[wm3798]

This covers the Kato conversion...
http://www.wmrywesternlines.net/st_bridges.php

I used a flat blade Xacto to go after the little mounting humps, then CA'd some Micro Engineering c55 bridge track to the beams.  Worked plenty well enough.

Lee

[nkalanaga]

In the 50s and earlier the minimum desired would be at least six feet over the highest car, to allow for a brakeman on the roof.  Less than that one would need telltales to warn him of the low clearance.  Note that that isn't the minimum allowable...