Riving knife question

Discussion in 'Carpentry and Woodworking' started by zepper, Oct 9, 2017.

  1. Oct 9, 2017 #1

    zepper

    zepper

    zepper

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    Hey guys,

    I understand how a table saw's riving knife makes cutting safer by holding the cut open behind the blade, preventing the wood from pivoting, contacting the side of the blade and kicking back.

    However, I don't understand why it has two positions—above the blade, for through cuts:

    [​IMG]


    ...and even with the top of the blade, for non-through cuts (e.g. kerfing):


    [​IMG]


    It's obvious the knife can't be higher than the blade during non-through cuts. But the rest of the time, what's the advantage of having it higher than the blade? Is there a reason to keep putting it back up there?
     
    Last edited: Oct 9, 2017
  2. Oct 10, 2017 #2

    nealtw

    nealtw

    nealtw

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    Most times that attachment get put some where safe.
     
  3. Oct 10, 2017 #3

    zepper

    zepper

    zepper

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    Seems to me the safest place is on the saw! But I don't have the kind of experience you do.
     
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  4. Oct 10, 2017 #4

    Sparky617

    Sparky617

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    On the TV shows they are always removed for visual clarity. The rest of the time they are removed because they get in the way.
     
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  5. Oct 10, 2017 #5

    slownsteady

    slownsteady

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    I would guess that it would offer some kick-back protection in the upper position.
     
  6. Oct 10, 2017 #6

    nealtw

    nealtw

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    Years ago, I bought one of those cheap plastic saws. One of the employees took it out of the box and set it up with all those attachments. We had not used it yet and the WBC dropped in for a visit and was checking out all the machines. When he walked past the new saw, he said, you don't need all that junk on there.
     

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