NAKAMURA TOME WT-300 REBUILD PART 2

Today, I’m showing you a Nakamura-Tome WT-300 or WT-30 machine that’s come in for a rebuild. I’m not sure if I sold this one before, but let’s dive into the details.

This machine uses box ways, which are excellent for cutting but have a downside. When they wear out, chips can build up and damage the ways. To fix this, we need to disassemble the entire machine down to its base, regrind the surfaces, and refit the sides. It’s a lot of work, but these machines are absolute workhorses.

Here’s a quick overview of the machine:

• It has a lower turret, a sub-spindle, a main spindle, and an upper turret (sometimes called turret one or two in the catalog).
• The sub-spindle was rebuilt about a year or two ago, so it’s in good shape.
• We’ll send the other spindles out for rebuilding and check all bearings, seals, and other components to see what needs replacement.

The main issue is with the lower turret. Chips fall into this area during cutting and get trapped, causing wear. You can see visible lines where the chips have worn down the surface. This is likely the master way or the gib, which we’ll confirm by pulling back the wipers. The wear causes problems like off-center drilling, especially with longer drill bits, and can throw off precision by a few thousandths of an inch. While the slides don’t feel terrible, the wear is noticeable.

This machine is part of a robotic cell and is built to last. Rebuilding it costs a fraction of buying a new one, which is why it’s worth the investment. Box ways are superior for cutting harder metals compared to linear guides, which are faster and cheaper to fix but less robust for heavy-duty work.

Here’s the rebuild plan:

• Pressure wash and regrind the bed.
• Inspect the motor, belts, actuators, and replace all lubrication to prevent future issues.
• Send the way covers to Metal in Motion in Rockford for repair—they do great work.
• Attempt to rebuild the ball screws; if that’s not possible, we’ll replace them.
• Since I can’t grind the bottom of the bed in-house due to rail interference, we’ll send it to a company in Ohio with the equipment to grind it properly.

This is going to be a fun project, and we’ll share more videos showing the process, including a detailed walkthrough of the machine’s internals. These machines have a ton of covers, so it’s rare to see them stripped down like this.

Thanks for watching! Stay tuned for updates.