Your K.O. Lee tool and cutter grinder is a precise monster of a machine.
It’s built to sharpen end mills, cut gears and handle demanding tooling work day after day. But like any workhorse, it needs the right parts to keep performing.
When critical components fail, your machine goes down. Production stops. Money bleeds away while you scramble for replacement parts.
Don’t let that happen.
LeBlond Service Manager Christopher Smith has rebuilt hundreds of K.O. Lee grinders. He knows which parts fail first and why. More importantly, he knows how to make them last longer.
Here’s his insider guide to the most critical K.O. Lee tool and cutter grinder parts you need to know about.
Precision Bearings for KB943 Work Head
What it does: Keeps everything tight to zero runout on your cutting tools. No slop. No wobble. Just precise cuts that hold the tolerances you need.
When to replace: When you can’t maintain zero runout anymore. If your cuts are getting sloppy, your bearings are shot.
How to maintain:
- Keep dirt and grinding dust away from the seals
- Check seals regularly for damage
- Clean your work head religiously
- Don’t let grinding dust build up under the seals
“Not keeping the work head clean is the fastest way to destroy these bearings,” Smith warns. “Grinding dust gets underneath the seals, tears them up, then makes its way into the bearing.”
6-Inch Draw Tube for 5C Collet
Background image via Dave Somerville
What it does: Reaches through the spindle to draw the collet into the adapter. Works with the 4-inch draw tube handle and 5C collet adapter to hold your tooling.
When to replace: When threads get stripped from overtightening or when the key breaks in the collet adapter and spins the threads out.
How to maintain:
- Keep everything clean
- Don’t get sloppy with your setup
- Avoid overtightening
- Standard use with proper care = 2-10 years of life
The lifespan depends entirely on how well you treat it. Clean operation can get you a decade. Abuse will kill it in months.
4-Inch Draw Tube with Handle & 5C Collet Adapter
What it does: The handle gives you the leverage to operate the draw tube system. The adapter holds 5C collets that grip your tooling.
When to replace: Same issues as the 6-inch tube. Stripped threads from overtightening or key failure.
How to maintain:
- Keep the collet adapter clean inside and out
- Make sure the key stays intact
- Don’t force anything
- Clean operation = years of reliable service
KB943 Drive Belt
What it does: Drives the KB943 workhead at a maximum of 400 RPM.
When to replace: When the belt gets frayed or damaged from dirt exposure. The KB943 workhead runs open, so it catches everything flying around your shop.
How to maintain:
- Keep your machine clean
- Don’t let dirt accumulate on the belt
- Expect annual replacement with daily 8-hour use
This isn’t a high-RPM application, so heat isn’t the enemy. Dirt is.
Wheel Dresser
What it does: Resurfaces your grinding wheel. Takes nicks out. Fixes uneven wear. Gets your wheel back to round and sharp.
When to replace: When the dressing wheel wears down too low or when you take a chunk out of it during operation.
How to maintain: You can’t. It’s basically a hand tool. When it’s done, it’s done.
Replacement frequency:
- Grinding shops running all day: 2-3 per year
- Machine shops with occasional grinding: 1-2 years
Once you buy the complete kit, you only need to replace the wheels. They’re inexpensive.
5C Collet Adapter
What it does: Holds 5C collets that grip your cutting tools and workpieces.
When to replace: When improper use damages the internal surfaces or when the key gets damaged.
How to maintain:
- Never put dirty collets into the adapter
- Keep grime out of the internal surfaces
- Make sure the key stays intact
- Clean everything before assembly
KB943 Workhead Housing
What it does: Houses the precision spindle system for your 5C collets and cutting tools. This is the heart of your tool grinding operation.
When to replace: Rarely. But when bearings fail and the outer race starts spinning, it can wear down the housing. At that point, bearings won’t hold properly, and you need a new housing.
How to maintain:
- Check inner and outer seals regularly
- Keep everything clean
- Address bearing problems before they destroy the housing
This is an expensive replacement that you can avoid with proper maintenance.
The Bottom Line on Maintenance
Every K.O. Lee expert will tell you the same thing: cleanliness and lubrication are everything.
Smith sees the same problems over and over:
- Grinding dust buildup destroying seals
- Lack of proper lubrication wearing out threads
- Dirty operation contaminating precision components
Regular maintenance can counter these issues. Here’s what to do:
Background image via Andy Kamashian
Modern K.O. Lee grinders come with maintenance schedules printed right on the machine. Older machines don’t have this luxury. But the principles remain the same.
Keep it clean. Keep it oiled. Address problems before they cascade into expensive failures.
Your K.O. Lee tool and cutter grinder is built to last decades. Give it the care it deserves, and it will keep delivering precision cuts long after cheaper machines have hit the scrap heap.
Contact LeBlond For K.O. Lee Tool & Cutter Grinder Parts
When you do need replacement parts, don’t settle for questionable aftermarket components. Your precision work demands genuine K.O. Lee parts that meet original specifications.
Contact LeBlond for genuine K.O. Lee replacement parts and expert service. We’ve been keeping these machines running for decades:
- Find online parts ON THIS PAGE.
- Call +1 (888) 532-5663 (Monday-Friday 8am- 4:30pm ET) & select Option 1.
- Or leave a comment below!
We look forward to hearing from you!
Banner background image via Andy Kamashian