A pipe bender that stands for months in an unheated workshop suffers from damp and condensation as much as from use. Rust forms on gears and slides, moving assemblies stick and the electronic board contacts oxidise, so a CNC machine stops communicating properly with its controller.
Below is an unscheduled service of a CNC pipe bender after a long shutdown. The same steps also work for routine preventive care of manual and hydraulic pipe benders.
What you will need
Important: Isolate the machine before starting, lock off the switch and hang a warning tag. On hydraulic models, release the system pressure. Do not open the control cabinet unless you are qualified for electrical work, and wear eye protection.
Step 1
Prepare the machine
Isolate the pipe bender, release hydraulic pressure and clear offcuts and swarf from the working area. Inspect gears, slides, carriages and bending rollers: note where rust is superficial and where parts have seized. Remove old dried dirt with a nylon brush and a rag.
Step 2
Free the oxidised gears
Aim WD-40 Multi-Use through the straw directly at heavily corroded gear teeth and leave it for a few minutes. It penetrates under the rust, displaces moisture and is gentle on sensitive parts. If an assembly is completely seized, use WD-40 Specialist Penetrant and give it longer.
Then turn the drive by hand, wipe away the loosened rust and repeat until it runs smoothly.
Step 3
Clean the CNC electronic board
Oxidised pins and connectors disrupt communication between the board and the controller. With the power off, spray WD-40 Specialist Contact Cleaner onto the board connectors and contacts. It dissolves oxidation and dirt, evaporates quickly and leaves no residue.
Let it dry completely before reconnecting the power.
Step 4
Treat the slides and carriages
Treat oxidised slideways and bending carriages with WD-40 Multi-Use through the thin straw, which puts the product only where it is needed. Wait a few minutes, run the carriage by hand along its full length and wipe off the dirt that comes out. In a workshop with several machines, refilling a sprayer from the WD-40 5 l can is more economical.
Step 5
Apply long-lasting grease
Once everything is clean and moves freely, apply WD-40 Specialist White Lithium Grease to the slides and gears. It does not run off vertical surfaces, holds up under load and keeps moving parts running smoothly, protecting them from sticking again.
Step 6
Test the machine
Remove tools and rags, restore power and run the pipe bender without a workpiece. Check every axis, listen for unusual noise and look for errors on the CNC panel, then make a test bend on an offcut of pipe.
Tip: If the machine will stand idle for more than a month, treat exposed metal surfaces with
WD-40 Multi-Use before shutting it down and cover it. Restarting will then take minutes rather than days.
What next
Inspect and lubricate the pipe bender monthly as preventive maintenance, and more often in damp unheated workshops. Record each service in the machine log so no cycle is missed.
These uses come from the experience of WD-40 users in many countries. Always follow the instructions and warnings on the product label.
More guides in «How to use».