Novice here - help with jointer jig

[John Chester404]

I'm having an issue with jointing. I made this jointer jig for my table saw here: https://www.youtube.com/watch?v=x3Nk057II4I .


I had a small square piece of wood that was roughly 6"x6" that I wanted to joint as it was just slightly off square. Using the jointer jig I ran the top edge and left edge through the saw. After I butted the top edge and left edge against my fence and ran the bottom edge and right edge through the saw. Unfortunately, it did not produce what I wanted. It was askew and not square. I did it again as I thought maybe I didn't have the jig tight against the fence. It came out more askew.


Thinking about it makes sense I suppose if I had clamped down the piece on the jig askew. However, I feel as if I'm missing something very simple using this jig. What is it that I'm doing wrong when jointing this piece to make square? My fence, blade, and jig are square. Thanks for any help.

[Mark Hockenberg]

Hi John,

You properly identified the variables - fence, blade and jig...

After you made the first two cuts (top and left), were those edges perfectly square? If those were not at 90, the final cuts would duplicate that error.

It sounds like either the error came in up front when using the jig to make the first two cuts, or perhaps the blade and fence aren't parallel.

Cheers,
Mark

[John Chester404]

Hi Mark - thanks for replying.

I believe I may have figured it out. When I clamped down the piece my 2 clamps were not even - they were offset. In that video I posted he uses that same jig to taper legs for a table in which he offset his clamps. I think that may be my issue. I will triple check squareness of my fence, etc.

If that is my issue how would I ensure my clamps are even? Eye ball it?

[Mark Hockenberg]

You won't be able to get good results by eyeballing the clamps. I re-watched the video and this jig is really meant for straight-lining a board with two uneven edges or for the tapering operation. It's really not an effective jig for cutting an edge square to another edge or for making two edges parallel.

For what you're trying to do, I would recommend the following (assuming the board has all edges uneven):

1) Run one edge using the jig you built to get the first straight line.
2) Use your tablesaw fence to cut the opposite edge parallel to the first edge.
3) Use your miter saw to cut the last two edges at 90 to the first two edges OR If you don't have a miter saw, use a miter gauge set at 90 on your table saw (if you do this, clamp your workpiece to the miter gauge to keep it in place and to keep your fingers clear)

[John Chester404]

That was my issue - I was trying to straight too many sides when I could use a crosscut sled for the short sides. I don’t know why I didn’t initially think of doing that.

Thank you for your help. Much appreciated