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RP-23 Bolsters

RP-23

Note: Specifications on this sheet are designed to permit easy interchange of trucks between cars.

For On3 Scale: D shall not exceed 3/8" on either body or truck bolsters.

(RP23-2)

Name
of
Scale		 P
Kingpin
Size		 E
Truck
Bolster
Hole		 D
Center Plate
Dia.		 Bc
Center Bolster Bearing
Above Top of Rail
Frt. Cars Pass. Cars
O, O(17) .112"(#4) .116 (#32 Drill) 1/4" 17/32" 43/64"
S .112"(#4) .116 (#32 Drill) 3/8"
----
Max		 13/32" 1/2"
OO .112"(#4) .116 (#32 Drill) 3/8"
----
Max		 11/32" 27/64"
HO .086"(#2) .089 (#43 Drill) 3/8"
----
Max		 5/16" 3/8"
TT .073"(#1) .081 (#46 Drill) 5/32" 15/64" 15/64"
HOn3 .086"(#2) .094 (#42 Drill) 1/4" 9/32"

 

  Bs Si So
Name
of
Scale 		Side Bolster Bearing
Above Top of Rail		 cc Distance Side
Bolster Bearings to Center
Freight Cars Pass. Cars Inside Type Outside Type
O, O17 5/8" 49/64" 17/32" 1"
S Side bearings not recommended.
OO Side bearings not recommended.
HO Side bearings not recommended.
TT Side bearings not recommended.
HOn3Side bearings not recommended.

Note: Use passenger car bolster bearing heights on tenders and high speed freight cars generally fitted in the prototype with passenger type trucks.

Body kits shall be supplied with the recommended kingpin and with body.

bolsters so designed that couplers will be at STANDARD height (see STANDARD S-1) when the bottom face of the body bolster center and side bearings are at recommended height (Bc and Bs respectively) above top of rail. Lower face of body bolster shall allow clearance for maximum center bearing diameter on truck bolster.

Truck bolsters shall have center hole diameter to accommodate the recommended kingpin and depth of the hole shall not exceed 5/64". Clearance below shall accommodate the recommended screw head, and clearance above shall accommodate the maximum diameter center bearing on the body bolster.

Insulating means shall be provided to prevent passage of current between the wheels and the car body.