Connecting Rod Boring Machine MB-125 Chinelatto - Ø0.6" to 5"

The connecting rod boring machine is used to enlarge and precisely adjust the holes in connecting rods where the engine bearings fit. The MB-125 works connecting rods from Ø0.6 to 4.9 inches (Ø15 to 125mm), allowing correction of out-of-roundness and hole wear. With 4 automatic rotations and adjustable table from 4.3-13.8 inches (110-350mm) between centers, it handles from small to large engines. Essential in machine shops to restore worn connecting rods and ensure proper bearing clearance.

The MB-125 has capacity from Ø0.6 to 4.9 inches (Ø15 to 125mm) for connecting rod boring. Main motor 1.0hp with 4 rotations on tool spindle: 320-570-1,010-1,730 rpm. The connecting rod table has 0.33hp motor with 3 automatic feeds at 0.6-0.8-1.0 IPM (15-20-25 mm/min). Adjustable table from 4.3-13.8 inches (110-350mm) between centers and 6.9 inches (175mm) height from spindle to table. Electrical supply 220V three-phase, total installed power 1.33hp.

The MB-125 accepts connecting rods with center distance from 4.3 inches to 13.8 inches (110mm to 350mm), covering from small car engines to truck engines. For connecting rods smaller than 4.3 inches (110mm), it includes special fixture with 2 pieces. The holes can be Ø0.6 to 4.9 inches (Ø15 to 125mm). Includes expander for clamping with 3 sets of blades and fixtures to center connecting rod with dial indicator. Table height allows connecting rods up to 6.9 inches (175mm) from spindle, handling virtually all market engines.

The automatic boring machine like the MB-125 has table with automatic feeds (0.6-0.8-1.0 IPM / 15-20-25 mm/min) and 4 preset rotations, ensuring uniform finish and productivity. Manual requires operator to control speed and feed manually, being slower but allowing greater control in special cases. Automatic reduces human error and operator fatigue, ideal for shops with volume. Both use the same boring tools, but automatic offers superior repeatability.

First center the connecting rod on table using fixture with dial indicator, then clamp with expander and blades. Choose the tool (0.24, 0.31 or 0.47 inches / 6, 8 or 12mm) and proper rotation among the 4 options. Tool rotates while table advances automatically, removing material from hole. Operator adjusts depth according to desired measurement. Process removes out-of-roundness and wear, leaving hole perfectly cylindrical for new bearing. Manual pump injects oil for cooling and lubrication.

With regular maintenance, the MB-125 lasts decades in machine shop. Replace fractional belts according to wear, maintain lubrication of bearings and ways. Check precision of dial indicators periodically. The boring tools (0.24, 0.31, 0.47 inches / 6, 8, 12mm) and inserts are consumables that get replaced. 1.0hp motor is robust for industrial use. Chinelatto offers replacement parts and technical support. Daily cleaning removes chips and oil, preserving machine precision.