Page 1 of 2 12 LastLast
Results 1 to 15 of 18

Thread: Corner Bridle Joint Cutting Issue

  1. #1

    Corner Bridle Joint Cutting Issue

    I'm having an issue with cutting the tenons and open mortises on some window sashes that I'm throwing together for a chicken coop and hoping you guys can help. When using my tenoning jig on the table saw, the leading edge of the piece that I'm cutting appears to cut straight and vertical. However, as the blade exits the backside of the cuts, it seems to cut a little bit more off at the bottom left side of the joint. Hopefully the picture below shows what I'm trying to describe. The red line is the corner that gets removed from the backside of the cut after the wood exits the blade; the front side of the cut remains square.

    tenon.png

    Does anyone have any ideas what might be causing this? It almost seems like the blade is flexing as I make the cut, however the problem happens regardless of the rate that I feed the material through, and no matter what blade I use. I can detect a slight wobble when spinning the blade by hand which appears to be due to some play the arbor and/or motor shaft. If wobble was the issue, wouldn't cutting slower then fix that since it would let the tooth that is farther out finish its cut?

  2. #2
    Join Date
    Aug 2018
    Location
    Michigan, USA
    Posts
    548
    A slight tear-out? Might try a sacrificial push block.

  3. #3
    Quote Originally Posted by Gary Ragatz View Post
    A slight tear-out? Might try a sacrificial push block.

    I wouldn't say it's a tear-out, it appears that the blade is actually cutting deeper at the end of the cut. The sides are cleanly severed and you can see the circular tooth marks where the cut got deeper than intended.

  4. #4
    Join Date
    Mar 2003
    Location
    SE PA - Central Bucks County
    Posts
    65,675
    Have you carefully checked the saw blade alignment to whatever is guiding your tenoning jig? It could be the blade or it could be the tenoning jig that's slightly skewed...I'd guess on the latter first if your saw otherwise cuts normally for everything else.
    --

    The most expensive tool is the one you buy "cheaply" and often...

  5. #5
    Is the clamping face of the tenon jig parallel to the blade? It would skew things a little so that the last bit of blade cut that corner a touch. Clamp on a much wider piece of scrap for a test cut and see if it is worse.

    Jim types a lot faster than I do And he likely didn't have to stop midway and let the dogs out.

  6. #6
    Thanks for the input guys. I did a quick initial alignment check of the tenoning jig, but it was pretty cold in the shop so I might have been careless; I will double check.

  7. #7
    Join Date
    Nov 2009
    Location
    Peoria, IL
    Posts
    4,443
    How sharp is your blade? Is the runner of the tenoning jig snug in the miter gage slot? Might be getting a slight wiggle as you exit.

  8. #8
    Join Date
    Mar 2003
    Location
    SE PA - Central Bucks County
    Posts
    65,675
    Bottom line is that the jig/workpiece has to move exactly parallel to the whole blade cutting arc...with the workpiece perpendicular to the table.
    --

    The most expensive tool is the one you buy "cheaply" and often...

  9. #9
    Quote Originally Posted by Richard Coers View Post
    How sharp is your blade? Is the runner of the tenoning jig snug in the miter gage slot? Might be getting a slight wiggle as you exit.

    Blade is brand new, and the runner is tight in the slot, that was the first thing I thought of as well. The issue seems to happen no matter what blade I'm using.

  10. #10
    Join Date
    Apr 2016
    Location
    Tasmania
    Posts
    2,162
    Often happens when the cutting action applies sideways pressure to the saw blade. There will be a misalignment somewhere. If you need to get the job done so the chooks don't freeze, try a sacrificial piece at the back. This has to be chunky enough to cop the wobble and leave your work piece intact. This should get you out of trouble until you check alignment. Saw blade parallel to table slot? Cheers

  11. #11
    Join Date
    Mar 2003
    Location
    SE PA - Central Bucks County
    Posts
    65,675
    And for all of the non-"down under or nearby" folks...a chook is a chicken.
    --

    The most expensive tool is the one you buy "cheaply" and often...

  12. #12
    Join Date
    Jun 2008
    Location
    So Cal
    Posts
    3,737
    Quote Originally Posted by Jim Becker View Post
    And for all of the non-"down under or nearby" folks...a chook is a chicken.
    If a chook is a chicken what’s a henway?
    Aj

  13. #13
    Join Date
    Mar 2006
    Location
    SoCal
    Posts
    22,492
    Blog Entries
    1
    Is it a thin kerf blade? I generally got very good performance with TK blades but, the saw and jigs had to be very well aligned. Something traveling an irregular path can push a TK blade a bit out of plane and it recovers as you exit the influencing material. the good news is that whether it is or isn't, setting up your saw and your accessories as true as possible leads to a more enjoyable shop time going forward.
    "A hen is only an egg's way of making another egg".


    – Samuel Butler

  14. #14
    It is a thin kerf .091? Freud blade. I was thinking that if it was deflecting that feeding the wood at a slower rate would fix that issue, but like everyone else said, maybe the alignment is not quite right.

  15. #15
    Quote Originally Posted by Andrew Hughes View Post
    If a chook is a chicken what’s a henway?

    Four to six pounds.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •