Turcite B for Milling Machine Guideways
Milling machines load their guideways in a different direction to a lathe: the cutting force pushes the table up or down against the ways and tries to lift the knee, so the liner has to stay bonded under alternating load as well as slide smoothly. Turcite B strip handles both, and it lets a worn table or knee be brought back to geometry instead of replaced.
Table, knee and ram interfaces
On a turret or vertical mill the table slides on the saddle, the saddle on the knee, and the knee on the column. Each of those interfaces carries a different load: the table takes the clamping and the cut, the knee carries the whole assembly plus the workpiece, and the column ways guide the knee over the full height of the machine.
Because the knee is heavy, its ways wear into a barrel shape — tight at the top and bottom of the travel, loose in the middle where the machine spends most of its working life. Relining the knee ways and re-machining the liner face restores a straight, uniform contact pattern instead of three separate contact zones.
Alternating load and bond integrity
A milling cut is interrupted by definition, so the load on the way reverses with every tooth. That reversing load is what peels a badly bonded liner: the strip is pushed down into the way, then released, thousands of times per minute. A proper bond with a fully wetted, gap-free adhesive layer is what keeps the strip in place.
Surface preparation decides the result more than the adhesive does. The metal must be clean, degreased and roughened, the treated face of the strip must be protected until the moment it is bonded, and the clamp pressure must be even across the full width of the strip. Any air pocket becomes a start point for peel.
Restoring geometry after machining
When a mill way is reconditioned, the metal surface is machined or ground first and the liner is then bonded and finished to bring the table back to its original height and parallelism. That sequence is deliberate: the liner is soft and easy to machine, so it is used as the final adjustable layer rather than as a filler over an uneven surface.
For a machine that also has a scraped finish on the mating way, the liner face is often left slightly proud and then scraped to the contact pattern. Spotting paste shows where the high points are, and a few scraping passes bring the contact up to a uniform distribution.
Materials for this application
- Turcite B Replacement Blue — All-purpose low-friction slideway strip for machine tool guideways.
- Turcite B Replacement Green — Green-grade slideway strip with a balanced friction and wear profile.
- Two Part Epoxy-Adhesive — High-strength two-component epoxy for bonding slideway strip to metal ways.
Technical guides for this machine
- Milling Machine Guideway Repair with Slideway Tape
- Slideway Liner Load and Pressure: Engineering Design Limits for PTFE Tape
- Slideway Liner Bonding Mistakes to Avoid
Frequently asked questions
- Will a liner hold on a mill table under interrupted cutting?
- Yes, provided the bond is done properly. Interrupted cutting loads the bond in peel rather than in shear, so surface preparation, even clamping and a full cure before machining matter more than on a continuously loaded slide.
- Should the liner be scraped or ground after bonding?
- Either works. Grinding gives a fast, uniform face; scraping gives a contact pattern and oil pockets that suit a hand-finished machine. Many rebuilders rough-machine and then scrape the final contact.
- How much liner thickness do I need on a knee?
- Enough to restore the knee height after the worn metal has been machined away, within the standard range of 0.8 to 3.2 mm. Measure the wear step first; ordering thickness by guesswork is the most common reason a reline ends up out of alignment.
Get a quotation for this application
Send the machine type, the axis, the length of each slide and the thickness you need, and we quote the strip, the two-part epoxy adhesive and the spotting paste together.