1. Mechanical Gear Adjustment (Mainstream of Traditional Mechanical Equipment)
Mechanical gear adjustment is the classic adjustment method for common desktop rebar bending machines which relies on mechanical gear switching to achieve angle control. Its core principle is to limit the rotation angle of the bending axis by changing the position of the "locating block/stop pin" and it is specifically divided into the following two types:
1. Fixed Gear Adjustment
The machine body is marked with preset bending angle gears with common gears being 90° 135° and 180° and some machines also having a 45° gear. To adjust you must first stop the machine manually insert the locating pin into the gear hole corresponding to the target angle and then start the machine again. The bending axis will automatically stop when it rotates to the position blocked by the locating pin thus completing the fixed-angle bending.
In terms of angle accuracy this method is affected by mechanical processing precision with an error usually ranging from ±2° to ±3° and it is suitable for scenarios where angle accuracy is not high such as stirrup bending in ordinary construction. In terms of operation convenience the adjustment steps are simple requiring only inserting and pulling out the locating pin without professional skills but the machine must be stopped for each adjustment which makes continuous angle switching impossible resulting in low efficiency and no custom angle function.
2. Manual Fine-Tuning Adjustment
This method adds a "fine-tuning screw" to the fixed gear adjustment. After completing the preset gear adjustment you can rotate the fine-tuning screw to push the locating block to move slightly with an adjustment range usually of ±5° to achieve precise angle correction. For example after presetting the 90° gear if the actual bending angle is only 88° you can move the locating block forward through the fine-tuning screw to make the bending axis rotate an additional 2° thus achieving a precise 90° bending effect.
In terms of angle accuracy the error can be reduced to ±1° to ±2° which is suitable for scenarios requiring a certain degree of angle accuracy such as bending of rebar frame nodes. In terms of operation convenience it still requires stopping the machine to manually adjust the screw and the fine-tuning process needs repeated testing (checking the angle after bending 1-2 rebars) which is slightly cumbersome but more flexible than fixed gear adjustment.
2. CNC Setting and Adjustment Method (Exclusive to CNC Equipment)
CNC desktop rebar bending machines realize angle adjustment through an electronic control system without the need for mechanical gear switching. Their core relies on "program settings + servo motor drive" and they are specifically divided into the following two types:
1. Direct Setting by Touchscreen/Keypad
The machine is equipped with a touchscreen or physical keypad and during operation you can directly input the target bending angle which supports any angle setting within the range of 0°-180° such as 30° and 120°. The system will automatically calculate the rotation stroke of the bending axis and drive the bending axis to rotate precisely to the target angle through the servo motor before stopping. Some high-end models also support the "angle memory" function which can store commonly used angles (such as 90° and 135° commonly used for stirrups) and you can directly call them for subsequent use without repeated input.
In terms of angle accuracy due to the high control precision of the servo motor the error is usually ≤±0.5° which is suitable for high-precision bending scenarios such as rebar processing for bridges and prefabricated components. In terms of operation convenience there is no need to stop the machine for adjustment and you can directly switch to the next target angle after the machine completes the bending of the current rebar. It supports custom angles and some models are equipped with an angle preview function which displays the comparison between the target angle and the actual angle on the screen making the operation efficient and easy for even beginners to master quickly.
2. Batch Programming
For batch processing scenarios such as needing to bend rebars at multiple angles in the same batch you can use the programming function of the machine to set multiple groups of angle parameters in the processing order such as bending 90° in the first step and 135° in the second step. At the same time you can also set auxiliary parameters such as bending speed and return position corresponding to each group of angles. After starting the program the machine will automatically complete the multi-angle continuous bending in the set order without manual intervention. For example when processing seismic stirrups you can set the continuous bending program of "135°-90°-135°" at one time and the machine will automatically complete the entire processing process.
In terms of angle accuracy it depends on the accuracy of program parameter settings and combined with servo motor control the overall error is ≤±0.5°. Moreover the angle consistency is good during batch processing which can avoid error fluctuations caused by manual adjustment. In terms of operation convenience it takes time to write the program in the early stage but it can be completed in 5-10 minutes after being familiar with the operation. However the efficiency is extremely high during batch processing which can reduce manual operation steps and support program saving so you can directly call it when encountering the same type of processing needs later.
