MZI Precision rebuilds Doosan milling and lathe spindles. Disassembly, cleaning, inspection, failure analysis and the quote are free until you approve the rebuild with a purchase order. A standard rebuild on a CAT 40 Doosan mill spindle typically runs around $7,500 and takes about three weeks. Rush service is available with a three to four day lead time.

What comes in

Eight in ten Doosan spindles that reach our shop are milling spindles. Lathe spindles are up this year, about double a normal year.

Doosan spindles are well made and competitively priced, and the rebuilds reflect that.

What a Doosan spindle is like inside

Doosan spindles sit in the middle tier of spindle engineering. They are well made and moderately priced. They do not carry the extreme complexity of a five-axis Mazak Integrex or a Kessler spindle on a DMG Mori.

That makes them straightforward to rebuild. The work is the standard rebuild done properly: disassembly, every part cleaned and inspected, bearings, seals and O-rings replaced, assembly, run, test and balance.

Why Doosan spindles fail

There is no Doosan-specific failure pattern. Failures track how the shop runs the machine.

Mold shops cutting Inconel and hard materials destroy spindles. Aluminum and brass are far easier on them. Coolant management matters more than who the manufacturer is. A crash, a broken tool, or coolant reaching the bearings will take out a Doosan spindle the same way it takes out any other.

If it sounds different, makes more noise, vibrates, or sounds rough, stop and call. Running it after a crash makes the damage worse and will cost considerably more to repair.

What drives the cost

A standard rebuild covers disassembly, cleaning, inspection, bearings, seals, O-rings, assembly, run, test and balance. On a CAT 40 Doosan mill spindle that typically runs around $7,500.

The number goes up when there is damage beyond the bearings. Chrome plating and grinding a taper, bearing journal or housing bore, a drawbar rebuild, or new parts can take a spindle to $12,000 to $13,000. Our quote details all the issues and what needs to be done to bring the spindle back to like-new condition.

Integral motor spindles cost more than belt or gear driven. The motor has a coolant jacket, encoders and proximity sensors, which add to the labor.

Before you ship it

  • Tell us the tool retention type: CAT 40, CAT 50 or HSK.
  • Send a good tool holder with its retention knob. We set the drawbar to your tooling and check drawbar pull force. Not needed for lathe spindles.
  • Send every rotating part: couplings, pulleys, the drawbar, and actuator parts.
  • Tell us everything you know about what happened: a crash, smoke, a noise, when it started. It does not change the quote. It gives us insight into the failure and points us to any issues with the spindle.
  • Fill out the repair request form and send it with the spindle, or scan it ahead.

Ship to 5572 Buckingham Drive, Huntington Beach, CA 92649. You get a notice when it arrives.

Questions shops ask

How long does a Doosan spindle rebuild take?

Three weeks, fifteen business days, for a standard rebuild. Rush service can be as fast as three to four days, for a 25% surcharge.

Is a rebuilt Doosan spindle as good as a new one?

A rebuild done right runs to the original specification. A spindle can be rebuilt again and again. A standard rebuild is about 30% of the cost of new. Even with heavy rework it is 50 to 60% of new.

What is the warranty?

One year from delivery of the rebuilt spindle.

Call (714) 379-6505. You will talk to a spindle expert, and with a little information we can diagnose the problem and tell you your best move. Or send the repair request form.

Talk to a Spindle Expert

Start with a phone call

Ed Zitney, President, MZI Precision Edward Zitney President (714) 475-4016 He has spent more than 44 years in spindle rebuilding and remanufacturing. He learned the trade over more than two decades at Precision Balancing & Analyzing, the shop long regarded in the industry as the standard for spindle work, later oversaw SKF Machine Tool Services, held service leadership roles at Setco, and wrote a published column on spindle remanufacturing for Fabricating & Metalworking.
Marco Guerrero, Partner, MZI Precision Marco Guerrero Partner (949) 374-0060 He came up on the shop side of this industry. He started with his hands, welding and fabricating for the racing industry, then spent fifteen years as general manager growing a machining job shop, the same kind of shop that sends MZI spindles today. He has sold CNC machines too, so he knows what new equipment costs and when a rebuild is the smarter call. Today he and Ed are partners in MZI Precision, and his standard is simple: every customer feels informed and supported from the first call to the day the spindle ships back.

Call (714) 379-6505 and describe what changed. With a little information about your spindle we can diagnose the problem and determine your best action.

What to expect on the call:

  • You talk directly with a spindle expert.
  • Some problems can be diagnosed over the phone, and a few do not require removing the spindle at all.
  • If your spindle should come in: disassembly, inspection, failure analysis, and a line-item quote, at no charge until your purchase order approves the rebuild.
Call (714) 379-6505 Request a Repair

MZI Precision is an independent rebuilder and is not affiliated with Doosan.