Compromise Bars
Select the two rail sizes being joined, hole pattern, and pair quantity.
ⓘ Identification & Terminology GuideA compromise joint transitions between two different rail sections; both sides of the joint must be identified.
Open Guide
A compromise joint transitions between two different rail sections; both sides of the joint must be identified.
Original MidStates identification schematic. Not to scale and not an installation or engineering drawing.
Compromise Bar Identification & Terminology
A joint designed to connect two different rail sections while maintaining the required relationship between running surfaces.
The two distinct rail sections joined by the compromise arrangement.
Some compromise bars are directional or position-specific; orientation must be verified from the actual part/project.
A specially manufactured rail transition that may be used instead of compromise bars in some applications.
How to identify what you have
- Identify both rail sections independently—do not describe the joint only as two nominal weights.
- Record the hole count and drilling pattern.
- Inspect both ends of the bar because the profile can change from one rail section to the other.
- Record any left/right, gauge/field or orientation markings.
What to measure
- Overall length
- Overall height
- Drilling pattern
- Bolt-hole diameter
- Profile dimensions at both ends when needed
What photos help MidStates
- Both faces
- Both end profiles
- All markings
- Rail A end with rail if available
- Rail B end with rail if available
Common identification mistakes
- Ordering as '115 to 132' without exact section designations
- Assuming bars are reversible
- Ignoring worn/transition rail conditions
Technical references & source notes
Reference index for rail sections, joint bars, compromise joints, tie plates, switches, turnout components, frogs, guard rails and fasteners.
Open authoritative public sourceReference for terminology and compatibility principles covering plates, spikes, anchors, joint bars and related industrial-track materials.
Open authoritative public sourceReference for rail-section terminology and dimensional identification. MidStates diagrams are original and are not copies of the UP drawing.
Open authoritative public sourceMidStates uses external publications to support technical facts and terminology. The explanatory text, diagrams and presentation on this page are original MidStates content and do not reproduce railroad or AREMA drawings.
* Required fields
Enter the rail weight if the exact section is unknown.
Enter the rail weight if the exact section is unknown.
Additional Information Optional
How do I determine the drilling pattern?
A: Measure from the end of the rail to the center of the first bolt hole.
B: Measure center-to-center between bolt holes.
Also note the number of holes and bolt-hole diameter if known. If you are unsure, leave the optional drilling-pattern field blank and MidStates can confirm it during follow-up.