Dewalt 611 erratic spindle speed and then dies


I’ve had my X-Carve up and running since Jan. 2016. I typically do small one off projects with it here and there so it has had relatively low use.

In the last year I have noticed the router speed behaving progressively more erratically with the end mill speeding up and slowing down randomly at times even though the speed setting is always set to 1. Earlier this month (Dec. 2019), the router completely stopped spinning during a carve. Luckily I heard it slowing down and stopped the carve before the end mill stopped spinning completely.

I replaced the Dewalt 611’s brushes with a new set and it fired right up and started carving again. However, when comparing the length of the “spent” brushes and the new ones, I see the spent brushes are at approximately 60 to 70% of new (reference pictures below), which makes me think they should have more life left. Total run time on these brushes was 30 hours 8 minutes.

I’ve done a couple more small projects with the new brushes and, although it runs, I have noticed the erratic rotating speed up/down to continue, but to a lesser degree than before.

So my questions are:

  1. Is 30 hours 8 min total brush life normal?
  2. Could 4 years of low usage have degraded the life of my 611 or brushes?
  3. What could be causing the erratic spindle speed up/down?

Any comments or advice is greatly appreciated.

Carlos (Chachin…)

Pictures; Spent Brushes on Left Side:

When you remove the top cover and look at the wire connected to the brush it should be free in the metal housing with the brush wire in the housing metal slot. The only thing that keeps the brush from going further into the armature is the brush wire hitting the front of the housing in the slot. It is possible the speed control is failing or could have dust in it. Moving it quickly back and forth between speeds may help for a while if that is it. It may be able to be blown out with compressed air. The speed should be on 1 for most operations. Below is a picture showing the brush and slot I am talking about.

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Thank you for the ideas James!! I will try your recommendations next time I have a project in the works and report back.

Happy new year!


There is nothing wrong with your brushes.
You Should get MUCH more wear than that. (they’re not even halfway worn out)
DeWalt has / had a problem with the variable speed control.
I had the same problem with mine when I bought it.
The router was replaced and I have not had a problem since.