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I'm just starting to learn how to use the skew chisel in spindle turning and after watching one of Alan Lacer's videos I decided to invest in a safety drive center, shown below:

Safety Drive Center

He had his students actually practice dig-ins with the safety centers to see what causes the dig-in and to change future behavior to avoid them. The dig-in with the safety center causes the piece to stop turning (with adjustable "cut-offs"), which is different than what you would see with a spur drive. It seems like a good way to learn.

I do have a question on its use. I know the tension of the pin can be adjusted via the hole on the side of the drive. Do I want any portion of the pin exposed between the cup on the end of the drive and the wood? Or do I always want to tighten the tailstock (which has a live center) such that the cup of the safety center in the headstock presses flush against the end of the wooden piece?

Thanks for comments/direction.

  • 2
    What guidance is provided by the maker on how to set and use it? – Graphus Apr 4 at 7:59
  • There's a link for it here: oneway.ca/index.php?route=product/… that gives a description for why you might use it and how to vary the tension in the point's spring but doesn't address the positioning. With steb drive centers, you'd tighten such that the sharp teeth are embedded in the wood, and the ones I've seen have the same type of retractable pin. I recently watched one of the Lacer videos where he does mention cutting grooves in the cup of the safety drive to get a better grip on the wood (as confidence grows), so I'm thinking flush is preferred. – gcbound Apr 4 at 14:56
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Friction drives allow the tail center to adjust the tension and allow or constrain spinning of the drive in reference to the blank.

The drive is actually the outer rim, not the inner point. The inner point is more for registering the blank and within reason, any tension is probably appropriate as long as the tail stock provides enough tension to turn the blank.

  • This makes sense to me. Just to add a bit to the discussion: Lyle Jamieson has a video on mounting wood blanks on a lathe (for bowls), and he uses a spur center with an adjustable pin to quickly find the balance point for turning on center. He keeps the pin just proud of the drive teeth during this process and wiggles the blank into a balanced position (without power: wiggle, test, wiggle, test, etc.). Once he's found the sweet spot, he tightens it such that the teeth of the spur drive are firmly embedded in the blank (and the pin is of course no longer proud of the teeth). – gcbound Apr 15 at 4:20

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