6" Jointer Knife Change

The Bradley Boys are at it again. They let neither lack of skill, misunderstanding of purpose or gaps in skill-set stay them from their task.

Here we have a perfectly innocent jointer (circa 1940's). Its only crime is having seen some decent amount of use since the last knife change. The Bradley Boys descend on the poor beast. Although on casters it is not nimble enough to navigate the craftily congested garage shop and so we catch it.

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Glenn takes a piece of glass and sticks it in place with some 3/4" magnets. The baggies make it easier to pick the magnets up when we're done. There are also two 1" magnets that are taped right up near the edge of the glass. They are taped as when the glass is moved out to the position we require, the magnets try to move back toward the outfeed table where there is more meat to magnetize toward (is that correct use of that term?). Before sliding the glass (and therefor the magnets) into position, the old knives are removed (no that's not rust, that's mahogany sawdust) and the knives fresh from the sharpener's are installed "pinky-tight".

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The gib and knife are positioned left to right. The glass is then slid so that the 1" magnets are over top-dead-center. Glenn uses a white pencil to make a mark as a visual queue for TDC to make things quicker when the head is rotated to the next knife. The "pinky-tight" gib screws are loosened and the knife jumps up against the glass thanks to the magnets. The gib screws are then snugged. Repeat for the other two knives.

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Check that each of the knives just brushes the underside of a reference tool held over TDC. Now go back around and tighten all the gib screrws

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Adjust the infeed table for a light cut and grab a piece of irregular stock out of the bin. A test run is done till two perpendicular side are completely milled. A machinist's square finds the Bradley Boys satisfied.

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We will use the nice newly sharp jointer tomorrow when we make vise jaws for a vise addition to the workbench.
 
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Those Bradley boys...always caught up in some type of caper. :D I've always thought the glass and magnet trick was brilliant. Thanks for posting the pics. :thumb:
 
Do you make house calls? I've got a nicked blade in my jointer that I've been avoiding for ages... (justkeep sliding the fence over!)

Who am I kidding, I'm daydreaming about a fire sale on Byrd jointer heads...
 
I will just add that this is one of those things that, if you get prepared before you approach it, is pretty easy to do. I definitely put 'changing jointer knives' in the category of "why did I wait so long!?!". I have found a great many things are not as all-involved as we may think. There are still plenty that are . . . . but this is not one of them :D.
 
Second what Jim just said. Glenn told me about this trick some time back and it just does not get easier.

Ok so now Glenn can u come up with some way i can make power happen from none.:) Cant run my jointer till i move. :(

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Ok so now Glenn can u come up with some way i can make power happen from none.:) Cant run my jointer till i move. :(

You mean you've never seen one of those Gilligan's Island bicycle generators before!?! Whip one up out of some scrap bamboo and jungle vines, set one of your kids on it and go to town.
 
Would it be possible to post a video of this process? I need to try this, but I'm having trouble visualizing how it is done. From the positive comments, this is obviously brilliant!
 
Thanks Rob, I see how that would be helpful. I will use this process and change my blades as part of my setting up process. Thanks.
Oh and thank you Bradley boys for the information.
 
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