tram_calc.py — Bed Tramming Calculator for KS1M / Rinkhals

Reads PROBE_ACCURACY output from the TRAM_BED Klipper macro and tells you exactly how many turns (and in which direction) to rotate each bed screw to level the bed.

Requirements

• Python 3.10 or newer (uses list[dict] type hint syntax)
• No external dependencies

Setup

1. Add the macro to Klipper

Paste the following into your printer config printer.custom.conf

[gcode_macro TRAM_BED]
description: Probe 3 lead screw positions (3 samples each) to guide manual bed leveling
gcode:
  G28
  SET_HEATER_TEMPERATURE HEATER=heater_bed TARGET=60
  SET_HEATER_TEMPERATURE HEATER=extruder TARGET=140
  M190 S60
  M109 S140
  G1 Z10 F600
  G1 X30 Y30 F6000
  PROBE_ACCURACY SAMPLES=3
  G1 Z10 F600
  G1 X320 Y30 F6000
  PROBE_ACCURACY SAMPLES=3
  G1 Z10 F600
  G1 X175 Y320 F6000
  PROBE_ACCURACY SAMPLES=3
  G1 Z10 F600
  G1 X175 Y175 F6000

Probe positions correspond to:

Corner	X	Y
Front-Left	30	30
Front-Right	320	30
Rear-Center	175	320

Usage

Run the macro

In Mainsail / Fluidd / Octoprint console, run:

TRAM_BED

Wait for all three PROBE_ACCURACY blocks to finish.

Copy the console output

Select and copy everything printed after you triggered TRAM_BED — you need the lines that contain PROBE_ACCURACY at X:... and average X.XXXX. For example:

$ TRAM_BED
21:39:25 
PROBE_ACCURACY at X:30.000 Y:30.000 Z:10.000 (samples=3 retract=2.000 speed=4.0 lift_speed=4.0)
21:39:33 
probe accuracy results: maximum 0.225000, minimum 0.221667, range 0.003333,average 0.223056, median 0.222500, standard deviation 0.001416
21:39:34 
PROBE_ACCURACY at X:320.000 Y:30.000 Z:10.000 (samples=3 retract=2.000 speed=4.0 lift_speed=4.0)
21:39:44 
probe accuracy results: maximum 0.336667, minimum 0.335000, range 0.001667,average 0.335833, median 0.335000, standard deviation 0.000680
21:39:44 
PROBE_ACCURACY at X:175.000 Y:320.000 Z:10.000 (samples=3 retract=2.000 speed=4.0 lift_speed=4.0)
21:39:56 
probe accuracy results: maximum 0.034167, minimum 0.030000, range 0.004167,average 0.031944, median 0.034167, standard deviation 0.001712

Run the script

# Default: T8 lead screws (Kobra S1 Max / KS1M)
python3 tram_calc.py

# M4 bed adjustment screws
python3 tram_calc.py M4

Paste the copied console output at the prompt, then press Ctrl+D (Linux/macOS) or Ctrl+Z + Enter (Windows).

Supported pitch presets

Argument	Type	mm / turn
T8	Lead screw	8.0
T4	Lead screw	4.0
T2	Lead screw	2.0
M3	Bed screw	0.5
M4	Bed screw	0.7
M5	Bed screw	0.8
M6	Bed screw	1.0

You can also pass any numeric value directly (e.g. python3 tram_calc.py 1.25).

Example output

=================================================================
  BED TRAM RESULTS (T8, 8.0 mm/turn)
=================================================================
  Corner 1 · Front-Left          z = 2.1234 mm ← do not touch
  Corner 2 · Front-Right         z = 2.0814 mm diff = +0.0420 mm → turn CW 00:19 (0.042 mm) ◄
  Corner 3 · Rear-Center         z = 2.1280 mm diff = -0.0046 mm → OK

  Worst deviation: 0.0420 mm

=================================================================

  CW  = clockwise → raises that corner
  CCW = counter-clockwise → lowers that corner
  HH:MM = turns:minutes, e.g. 00:30 = half a turn, 01:00 = one full turn

Corner 1 is always the reference — do not adjust it. Adjust the remaining corners per the instructions.

A deviation ≤ 0.05 mm is shown as OK and requires no action.

Before / After

Running TRAM_BED and adjusting the screws per the calculator output reduces bed deviation significantly.

Before — range 2.65 mm	After — range 0.41 mm

How to adjust

1. Turn off the printer and disconnect power.
2. Lay the printer on its side to access the bottom.
3. Secure the pulleys! Image below.
4. Remove the hook tension spring to fully release belt tension follow official guide: Kobra S1 Max – Z-axis Belt Replacement Guide
5. Move pulleys acording to the script output (be sure about CW, CCW = bed up / bed down)
6. Reasamble
7. After adjusting all screws, re-run TRAM_BED and the script to verify.

Pulley securing tip

When routing the belt around the three bottom pulleys, the pulleys tend to shift and fall out of position. Secure all three pulleys with a strip of tape before threading the belt — this keeps them locked in place while you work and makes routing significantly easier. Remove the tape once the belt is fully seated and the tensioner is tightened.