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RP-12.6 Turnout Dimensions
HOn3 Scale
Look here for a larger printable copy of this diagram.
Design by Clarence H. Hill
Jump to Frog Numbers 8, 9, & 10.
| (1) | FROG NUMBERS | 4 | 5 | 6 | 7 |
|---|---|---|---|---|---|
| PROPERTIES OF CURVED SWITCHES | |||||
| (2) | Rail Length | 1-1/2" | 1-1/2" | 1-1/2" | 2-3/8" |
| (3) | Point Angle * | 2d 01' | 2d 01' | 2d 01' | 1d 20' |
| (4) | Heel Spread [+] | 3/32" | 3/32" | 3/32" | 3/32" |
| (5) | Heel Angle * | 5d 12' | 5d 12' | 5d 12' | 3d 09' |
| (6) | Switch Radius | 27" | 27" | 27" | 75" |
| (7) | Mid-Ordinate | .011" | .011" | .011" | .010" |
| LEAD TO THEORETICAL POINT OF FROG | |||||
| (8) | Lead | 3-5/16" | 3-5/8" | 4" | 5-1/2" |
| CLOSURE DISTANCE | |||||
| (9) | Straight Rail | 1-7/16" | 1-11/16" | 2" | 2-9/16" |
| (10) | Curved (Length) | 1-15/16" | 1-23/32" | 2-1/32" | 2-19/32" |
| (11) | Rail (Radius) | 9" | 16" | 27" | 30" |
| GAGE LINE OFFSETS ON CURVED CLOSURE RAIL | |||||
| (12) | 1st Point Y1 [+] | ||||
| (13) | 1st Point X1 | ||||
| (14) | Mid-Point Y2 [+] | 13/64" | 13/64" | 13/64" | 13/64" |
| (15) | Mid-Point X2 | 2-5/16" | 2-7/16" | 2-1/2" | 3-13/16" |
| (16) | 3rd Point Y3 [+] | ||||
| (17) | 3rd Point X3 | ||||
| PROPERTIES OF FROGS | |||||
| (18) | Frog Angle * | 14d 15' | 11d 25' | 9d 32' | 8d 10' |
| (19) | Overall Length | 1-1/16" | 1-1/4" | 1-3/8" | 1-1/2" |
| (20) | Toe Length | 3/8" | 7/16" | 1/2" | 9/16" |
| (21) | Heel Length | 11/16" | 13/16" | 7/8" | 15/16" |
| (22) | Toe Spread | 3/32" | 3/32" | 5/64" | 5/64" |
| (23) | Heel Spread | 11/64" | 5/32" | 9/64" | 9/64" |
| POINT OF FROG TO INTERSECTION OF CENTER LINES | |||||
| (24) | PF to ICL | 1-21/32" | 2-1/16" | 2-15/32" | 2-29/32" |
| DATA FOR CROSSOVERS -- PF to PF ON PARALLEL TRACKS | |||||
| Distance for 1-3/4" Track Centers Along: | |||||
| (25) | Straight Track | 3-9/16" | 4-9/16" | 5-1/2" | 6-3/8" |
| (26) | Crossover Track | 3-13/16" | 4-11/16" | 5-5/8" | 6-1/2" |
| Increment for 1/8" Change in Track Centers Along: | |||||
| Straight Track | 1/2" | 5/8" | 3/4" | 7/8" | |
| Crossover Track | 1/2" | 5/8" | 3/4" | 7/8" | |
Return to Frog Numbers 4, 5, 6, 7
| (1) | FROG NUMBERS | 8 | 9 | 10 |
|---|---|---|---|---|
| PROPERTIES OF CURVED SWITCHES | ||||
| (2) | Rail Length | 2-3/8" | 2-3/8" | 2-3/8" |
| (3) | Point Angle * | 1d 20' | 1d 20' | 1d 20' |
| (4) | Heel Spread [+] | 3/32" | 3/32" | 3/32" |
| (5) | Heel Angle * | 3d 09' | 3d 09' | 3d 09' |
| (6) | Switch Radius | 75" | 75" | 75" |
| (7) | Mid-Ordinate | .010" | .010" | .010" |
| LEAD TO THEORETICAL POINT OF FROG | ||||
| (8) | Lead | 5-7/8" | 6-3/16" | 6-1/2" |
| CLOSURE DISTANCE | ||||
| (9) | Straight Rail | 2-7/8" | 3-1/16" | 3-5/16" |
| (10) | Curved (Length) | 2-29/32" | 3-3/32" | 3-11/32" |
| (11) | Rail (Radius) | 42" | 55" | 75" |
| GAGE LINE OFFSETS ON CURVED CLOSURE RAIL | ||||
| (12) | 1st Point Y1 [+] | |||
| (13) | 1st Point X1 | |||
| (14) | Mid-Point Y2 [+] | 13/64" | 13/64" | 13/64" |
| (15) | Mid-Point X2 | 3-7/8" | 3-15/16" | 4" |
| (16) | 3rd Point Y3 [+] | |||
| (17) | 3rd Point X3 | |||
| PROPERTIES OF FROGS | ||||
| (18) | Frog Angle * | 7d 09' | 6d 22' | 5d 43' |
| (19) | Overall Length | 1-11/16" | 2" | 2-3/16" |
| (20) | Toe Length | 5/8" | 3/4" | 13/16" |
| (21) | Heel Length | 1-1/16" | 1-1/4" | 1-3/8" |
| (22) | Toe Spread | 5/64" | 5/64" | 5/64" |
| (23) | Heel Spread | 9/64" | 9/64" | 9/64" |
| POINT OF FROG TO INTERSECTION OF CENTER LINES | ||||
| (24) | PF to ICL | 3-5/16" | 3-23/32" | 4-1/8" |
| DATA FOR CROSSOVERS -- PF to PF ON PARALLEL TRACKS | ||||
| Distance for 1-3/4" Track Centers Along: | ||||
| (25) | Straight Track | 7-5/16" | 8-1/4" | 9-3/16" |
| (26) | Crossover Track | 7-7/16" | 8-3/8" | 9-5/16" |
| Increment for 1/8" Change in Track Centers Along: | ||||
| Straight Track | 1" | 1-1/8" | 1-1/4" | |
| Crossover Track | 1" | 1-1/8" | 1-1/4" | |
* the d stands for degrees (2d 01' is 2 degrees 01 minutes)
NOTES:
- a. Recommended to use gages for dimensions marked [+]
- b. Switch heel joints should not be out of square more than 1/32".
- c. Refer to RP-15.1 for suitable rails.
- d. Slip-on joint bars may be used up to 1/4" long and B&S gage No. 31 thick. The fit must be snug on the base of the rail. At the heel of the switch it may be necessary to cut away a portion of stock rail base.
Return to Frog Numbers 4, 5, 6, 7 or 8, 9, & 10.