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Adjusting spring loaded jointer knives with set screws

3052 Views 2 Replies 2 Participants Last post by  TFKeefe
I have a JET Benchtop 8" Jointer/Planer combination machine. The knives
are supported by set screws to adjust the height and are spring loaded.
There are six gyb screws that hold the blade in the cutter head.

I am a bit confused as to why there are both set screws and springs. It
seems to me that the springs just complicate knife setting operations.
If I set the knives by allowing the springs to push the knives up against
a reference (e.g., a straightedge) the the set screws play no role and
are simply snugged up after the gyb screws have been tightened.

On the other hand, I can adjust the set screws and then push the blade
down against the set screws as I tighten the gyb screws. Following this
I can check my work using a dial indicator. But this makes no use of the

I am tempted to remove the springs next time I adjust the knives as they
just seem to complicate things. Any thoughts on this idea?

1 - 3 of 3 Posts
I thought you adjusted the set screws to make the knife the correct height. The compressed springs then push the knives up so they can be more easily grasped for removal when the gib bolts are released.

However, to quote Dennis Miller- "that's just my opinion, I could be wrong".
The springs make it much harder to tighten the gyb bolts and the result is
that with the same set screw settings the blade may be a little higher or
lower when I am done.

I am wondering if it would be safe to remove the springs? It seems that
the gyb bolts are what really secures the knives. Not the springs or the
set screws. Thanks.

1 - 3 of 3 Posts
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