# My simple inexpensive tool and method to set jointer knives



## GaryK (Jun 25, 2007)

Starting out my life as a machinist and evolving into an engineer made the, intimidating for some, task of changing the blades on my jointer fairly straight forward.

I had all the tools I needed to do the job, but I wanted a simple. fast foolproof way to do it.

There are really 2 things you need to do.

1. Find amost top dead center for the blade.

2. Set your new blades 1 to 2 thousands of an inch above the outfeed table.

The first is simple using a a scale

First line up the edge of the outfeed table to an even inch number on your scale. 7 in this example.










Then by hand (unplug it first!) rotate the cutter clockwise so that the blade picks up and moves the scale forward. It moved it about 3/16" in this example.










Then just rotate the cutter back to move the scale almost 1/2 the distance and you will be close to top dead center.
It doesn't matter which side of the 1/2 way point you are at as long as you are about 1/16" from it.










Then just take a piece of wood and wedge it in to keep the cutter head from rotating. This should take all of about 1 minute to complete.

Next step, setting the blade height.

I have seen various magnetic tools for doing this, but here is a way to make you own. I went to a hobby store and bought a package of 10, 1/2" diameter "super magnets" for about $3. I had two pieces of steel of steel laying around so I used them. Aluminum would work as well.

I stuck 3 of the magnets to my jointer table. One spaced further away from the other 2. Then I put a drop of epoxy on each magnet and set my steel bar on it. Once dry those magnets will be perfectly flat on that bar.










Then after removing and installing your new blades (loosely), set the single magnet over the blade while sticking the tool to the table. Put one near each end of the blade making sure you to cover screw that tightens your blade.










Raise the blade up until it sticks to the magnet and tighten it there. You are done with that blade.

Now the reason for not setting the blade while not at top dead center, is so that when you install your new blade it will be just a little bit higher than the outfeed table.

If it's exactly the same height you will keep "bumping" into it with your stock.

It should take 5 to 10 minutes per blade.


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## a1Jim (Aug 9, 2008)

As usual you've got it down pat Gary. If it's in a person's budget I say avoid this all together with a spiral head jointer.


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## PaulJerome (Feb 4, 2010)

Thank you Gary for taking the time and effort to show us all how simple this can be. I really appreciate it. It will save me some time and effort. Great job!


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## patron (Apr 2, 2009)

the center high trick
is the hardest part of setting these knives

this is the best solution
i have ever seen for that

thank you


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## Karson (May 9, 2006)

Great design on the jig and head setting trick.


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## DIYaholic (Jan 28, 2011)

GaryK,

Nice tutorial. You make it look so simple. Good job!

Could you stop by my shop and give a demonstration (that is, the next time I need to reset/sharpen/change blades). Lol.

Thanks for posting this. I need to calibrate/setup a jointer that I recently purchased and your jig/instructable is "Just what the Doctor ordered".


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## bubinga (Feb 5, 2011)

I have watched videos, and read descriptions on setting jointer knives, and wondered why most of these people don't lock the cutter head in position.
You mentioned using a wedge, which is the way I have always done it.
I didn't see the wedge in your pictures, I put mine in front.
When I'm done the small wedge and the rest of the tools, for setting the knifes, are put away in one spot for the next time
*Great little jig set*.
I was going to buy some of those little magnets, for other things, but the shipping was as much as the magnets.
I never thought about the hobby store, great idea, there is one close by, I have been to, and they probably have those little magnets, so I will go check it out. Thanks


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## CanadianWoodChuck (Sep 8, 2007)

Thanks Gary, I would comment on your editorial but I'm busy setting my jointer knives.  Thanks


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## saddletramp (Mar 6, 2011)

Boy, that is the easiest way to do this onerous (in the past) task that I've seen. Thanks!!


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## ScottN (Jan 24, 2011)

Changing jointer blades is a tedious job and I like your ideas. But I'm confused as to why you would want to be 1-2 thousands of an inch higher. I've always set them to the same height as my out feed table. Whats the benefit of going higher? It just makes sense to me to keep them at the same height.


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## GaryK (Jun 25, 2007)

*bubinga* - You don't see the wedge because I wasn't actually changing the blades at this time. Just taking pictures.

*ScottN* - I have found that when setting it exactly flush, I "bump" into the outfeed table sometimes. The extra difference assures that I never do. It has no affect on the jointing operation. Plus it makes the find top center a little easier having something to work with.


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## NBeener (Sep 16, 2009)

Magic !

So … do I have this right ? ISTR hearing/reading that … with metal (like the straight edge) ... you have to be REALLY careful not to nick the blades, during this sort of process.

Are they truly THAT soft/fragile ?

Not a thread-jack. Just a question about this brilliant, and near dummy-proof method


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## devann (Jan 11, 2011)

Thanks Gary, I like the magnet trick.


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## Tikka (May 14, 2007)

nice one Gary


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## jusfine (May 22, 2010)

The problem I had when installing my last set of knives was that the blades rose slightly when I tightened the screws down.

Not sure how wide your jointer is (mine is 8" and has 5 screws), but I will try this next time and see if it helps.


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## SCOTSMAN (Aug 1, 2008)

The Austrian Felder company have the easiest idea they have an inbuilt frame which comes out to fit the jointer knives when it's returned it clicks into be locked at the correct height cannot be too high or low you can change knives in seconds as oposed to a long drawn out affair. Alistair


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## D_Allen (Oct 11, 2010)

I have a question/observance. It was always my understanding that the outfeed table should be exactly the same height as the top-dead height of the blades. It seems to me that even at .002", when the stock gets to the point when you would put downward pressure on the outfeed table, the stock would tip down on that side. I realize that the stock is probably flexing more than that but it seems it would also cause the jointed edge to be not quite perfectly straight. It would also seem to me that bumping into the outfeed table would indicate that the blades are set lower then the outfeed table.


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## GaryK (Jun 25, 2007)

*D_Allen* - Technically and theoretically you are correct.

The .002" won't effect anything and just helps getting the part smoothly on the outfeed table.

Making a final pass with a perfectly sharp leading edge, I have found that any pressure on the end of the board will catch on the outfeed table.

I mainly do it for the first couple of passes when the lumber is not flat. It just gives it a little extra clearance.


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## Grandpa (Jan 28, 2011)

I think the knives are that fragile Neil. Be careful to not nick them. That is the reason we are taught to not set our manual hand planes on their shoe. Instead we lay them on their sides.


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## larryw (Feb 10, 2011)

Thanks Gary for sharing this info, much appreciated.


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## FatherHooligan (Mar 27, 2008)

Thank you Gary. Figuring out top dead center has baffled me, your method looks dead easy to do.


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## Broglea (Dec 9, 2009)

Easy, inexpensive and just the way I like it. Thanks Gary!!


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