Jointer and planer knives setting jig.

[Liem Tran]

I'm trying to decide which planer and jointer knives setting jigs to buy. Any recommendations?

[Brian Hale]

I use a 12" straight edge for the jointer and the guide that came with my planer (Bridgewood 15")

Brian :)

[Tom Hamilton]

I recently installed new knives in my 1948 Boice-Crane 6" jointer. This was a first time effort for me. The knife setting article by Robert Vaughn on OWWM.com came in very handy and answered all my questions. There's even a video you can download for more specific instruction. I'm gettting smooth and even results.

Also, a google will get you several alternative methods using shop made devices.

So, to answer your question you may not need to buy a jig to change/set your knives.

Good Luck. Tom

[Andy Fox]

I purchased and then returned a magnetic jointer knife setting jig. I was able to get within .001" using a straightedge (cheap combination square). I was only able to get within .010" using the jig. I used a dial indicator to get a feel for just how far the knife should move the straightedge when set properly.

[Jon Healy]

I copied this from another site. The poster swears by it and I copied it for next time I need to do my jointer. If it works...great. If it doesn't...sorry.

Well here is how I do jointer knives:

get a piece of straight hardwood about 3/4 x2x14" long . make sure it is straight as it is a reference for all the operations that follow. The stick is always used off the outfeed table, it is the reference table .



1.If you do not have a top dead center mark on your fence you can find TDC by setting the stick on the outfeed table. Make a reference mark on the stick right at the edge of the outfeed table on the stick. Now with the jointer unplugged, hold down the stick with gentle pressure and rotate the jointer head by hand. As you do the knife will catch on the knife and move toward the infeed table. Let it do so and when it stops moving forward make another reference mark on the stick. This distance represents the distance that the knife is set above the outfeed table in an arc which makes it appear to be much more than the .001 or .002" is really is above the table. This clearance is necessary so that when you joint board the end doesn't catch on the outfeed table as you push the stock across the jointer. Now make a third mark on the board halfway between the two existing marks. This is going to represent the TDC of the cutter arc and so you should try and get as close to the center as you can. Set the stick back on the outfeed table and align the mark with the outfeed edge of the table. Once again using the same knife as you did to find the length and in about the same position on the knife rotate the knife until the center mark is aligned with the edge of the outfeed table. Stop the rotation and hold the cutter head in this position. Now make a vertical mark on the fence that aligns the edge of the knife to the fence. I actually scribed a line on my fence with a scribe so I always have this reference to work off of anytime I have to change knives. This is the reference point that determines all future work in changing knives.


Pull out ONE knife and mark the cutterhead as # 1. Clean out the slot and clean up the gib and the screws so that foregn material has no effect on the gib and the knife. If the head uses springs to lift the knife make sure they are all still there. They are small and get lost occsionally so it pays to look.
Now I set one fresh knife in the slot and put the gib in to and run the screws out just for enough to just touch the knife. Roughly set the knife so it aligns with the witness mark on the fence Tighten the screws a little at a time working form the center outward. Tighten a little move to the next screw, tighten, move,tighten move etc.
After you have the screws all tightened down, put your stick back on the outfeed table. I usually start with the stick near the fence. Make a new reference mark on the stick perferablly on a different side of the stick. One thing to remember here is that these marks are the ones you are going to use to set the other knives and so make sure they are accurately located. Once again, rotate the knife head and when the stick stops make another mark. Now, move the stick across the width of the jointer and align the first mark with the out feed table and using the same light pressure on the board rotate the knife again.
If the board stops at the second line then the knife is parallel ACROSS the width of the blade and probably does not need any more adjustment. You can check the knife in a couple of more places and I would on jointers wider than 8" to make sure the knife is not being forced higher or lower by the gib screws.
If the marks do not align then the distance the mark is from the second line will tell you what is wrong with the alignment ( if the board does not reach the line the knife is set too low , if it goes past it, it is set too high)loosen up the knife and reset it.
Once you get the first knife aligned go through the process again with knife #2 . After you get to the knife set and tightened in then put the stick on the outfeed table again over toward the fence and rotate the head as before. If the knife pulls the board to the second lineagainst the fence and on the outside then the #1 and #2 knives are in the same plane and you can move on to the #3 knife
Once again the same process and if all stays put because you have tighten all the gib screws equally and paid close attention to the stick you should be able to confidently straighten and flatten boards with no or very little ripple
I usually run two boards at this point to assure that all the work I have done is indeed right.



I just spent 30 minutes describing the process outlined here and I can set jointer knives using the above method on a 20 " jointer in about the same time. I consistantly change out knives on 6 and 8" jointers in about 15 minutes. I have been doing it on a regular basis for about 15 years now following this procedure and I think I have had to go back an reset knives maybe twice in that time (once because a knife slipped after I installed it due to sawdust between the gib and the knife and once because I didn't do it right




Other posters agree that this system works well and is fast.
Good luck.

[Sam Chambers]

Liem:

I use the Mini Planer Pals on my 12" Delta planer, and it does a great job. Makes knife changes fast and accurate, and they're fairly inexpensive.

I liked it so much that I bought the Jointer Pals. Unfortunately, they're not nearly as good, and I stopped using them.

[glenn bradley]

My jointer has cam bolts that allow height adjustment. Those along a straight-edge work fine for my 6", a larger machine may be more involved.

[glenn bradley]

My jointer has cam bolts that allow height adjustment. Those along a straight-edge work fine for my 6", a larger machine may be more involved.

[Jeff Singleton]

I have a 16" Wadkins jointer with a modern clamshell head with shewd knives. A dial indicator is the only way to get them dead on. My knives have a little slot at each end for the jackscrew to fit into so you can adjust up and down with ease. I have tried Magna Set and straight edges on other jointers and have always gone back to the dial indicator. My planer has a Terminus head so no setting is required.

Jeff Singleton:)

[Joe Spackle]

I copied this from another site. The poster swears by it and I copied it for next time I need to do my jointer. If it works...great. If it doesn't...sorry.

Well here is how I do jointer knives:

get a piece of straight hardwood about 3/4 x2x14" long . make sure it is straight as it is a reference for all the operations that follow. The stick is always used off the outfeed table, it is the reference table .



1.If you do not have a top dead center mark on your fence you can find TDC by setting the stick on the outfeed table. Make a reference mark on the stick right at the edge of the outfeed table on the stick. Now with the jointer unplugged, hold down the stick with gentle pressure and rotate the jointer head by hand. As you do the knife will catch on the knife and move toward the infeed table. Let it do so and when it stops moving forward make another reference mark on the stick. This distance represents the distance that the knife is set above the outfeed table in an arc which makes it appear to be much more than the .001 or .002" is really is above the table. This clearance is necessary so that when you joint board the end doesn't catch on the outfeed table as you push the stock across the jointer. Now make a third mark on the board halfway between the two existing marks. This is going to represent the TDC of the cutter arc and so you should try and get as close to the center as you can. Set the stick back on the outfeed table and align the mark with the outfeed edge of the table. Once again using the same knife as you did to find the length and in about the same position on the knife rotate the knife until the center mark is aligned with the edge of the outfeed table. Stop the rotation and hold the cutter head in this position. Now make a vertical mark on the fence that aligns the edge of the knife to the fence. I actually scribed a line on my fence with a scribe so I always have this reference to work off of anytime I have to change knives. This is the reference point that determines all future work in changing knives.


Pull out ONE knife and mark the cutterhead as # 1. Clean out the slot and clean up the gib and the screws so that foregn material has no effect on the gib and the knife. If the head uses springs to lift the knife make sure they are all still there. They are small and get lost occsionally so it pays to look.
Now I set one fresh knife in the slot and put the gib in to and run the screws out just for enough to just touch the knife. Roughly set the knife so it aligns with the witness mark on the fence Tighten the screws a little at a time working form the center outward. Tighten a little move to the next screw, tighten, move,tighten move etc.
After you have the screws all tightened down, put your stick back on the outfeed table. I usually start with the stick near the fence. Make a new reference mark on the stick perferablly on a different side of the stick. One thing to remember here is that these marks are the ones you are going to use to set the other knives and so make sure they are accurately located. Once again, rotate the knife head and when the stick stops make another mark. Now, move the stick across the width of the jointer and align the first mark with the out feed table and using the same light pressure on the board rotate the knife again.
If the board stops at the second line then the knife is parallel ACROSS the width of the blade and probably does not need any more adjustment. You can check the knife in a couple of more places and I would on jointers wider than 8" to make sure the knife is not being forced higher or lower by the gib screws.
If the marks do not align then the distance the mark is from the second line will tell you what is wrong with the alignment ( if the board does not reach the line the knife is set too low , if it goes past it, it is set too high)loosen up the knife and reset it.
Once you get the first knife aligned go through the process again with knife #2 . After you get to the knife set and tightened in then put the stick on the outfeed table again over toward the fence and rotate the head as before. If the knife pulls the board to the second lineagainst the fence and on the outside then the #1 and #2 knives are in the same plane and you can move on to the #3 knife
Once again the same process and if all stays put because you have tighten all the gib screws equally and paid close attention to the stick you should be able to confidently straighten and flatten boards with no or very little ripple
I usually run two boards at this point to assure that all the work I have done is indeed right.



I just spent 30 minutes describing the process outlined here and I can set jointer knives using the above method on a 20 " jointer in about the same time. I consistantly change out knives on 6 and 8" jointers in about 15 minutes. I have been doing it on a regular basis for about 15 years now following this procedure and I think I have had to go back an reset knives maybe twice in that time (once because a knife slipped after I installed it due to sawdust between the gib and the knife and once because I didn't do it right




Other posters agree that this system works well and is fast.
Good luck.

It does work well I know the OP :D

[Per Swenson]

This might help some.....

http://www.sawmillcreek.org/showthread.php?t=20579&highlight=jointer


Per

[Larry Cooke]

This might help some.....Per,

Why that's just way too simple, to adjust them knives don't you need digital dial indicators, a 48" starrett straight edge, and a laser leveling system to do it? :D

I thank you for your great idea. Glass and magnets, who'd thunk it...

Larry

[Vaughn McMillan]

Brilliant idea, Per. Even though might not have come up with it yourself, I'll always consider it your trick when I use it. Thanks for passing it on.

- Vaughn

[Joe Spackle]

How do you repeat TDC with the glass?

[Per Swenson]

I am not a tech writer.

Uncomplicated version.

TDC is always going to be about the cutter head.

Not the tables. You need to find it only once.

Then scribe a mark on the bearing housing.

Corresponding marks on the head.

It should be one of the first things you do on intial setup

of a brand new Jointer. My father marked this one in 1964

when I was 6 years old. Never changes.

Per

[Joe Spackle]

I am not a tech writer.

Uncomplicated version.

TDC is always going to be about the cutter head.

Not the tables. You need to find it only once.

Then scribe a mark on the bearing housing.

Corresponding marks on the head.

It should be one of the first things you do on intial setup

of a brand new Jointer. My father marked this one in 1964

when I was 6 years old. Never changes.

Per
so did he find TDC a DI or the glass or with a stick or ???????

Dad had to find it some way

Just curious........

[Dennis Lopeman]

I'm googling this right now! upon first couple links and reads, it doesn't look easy!

[Adam Potack]

I did something similar to the glass & magnets. I sank a magnet flush with a piece of 3/4 mdf, covered it with blue tape. Wish I thought of putting a magnet on the back end but holding by hand worked. This worked well It din't take too long to set my jointer knives, they were straight & all at the same height.

I cheated on TDC. I tweaked the outfeed table after setting the knives.

[Dan Karachio]

I agree, for jointer knives it is all about finding Top Dead Center, not the jig. In addition, to marking TDC, you need a way to hold it there. I found that once I can lock the head at TDC for each blade, it is fairly simple and almost fool proof to set the blade height whether using a magnetic jig or straight edge. If you don't lock it, it can and will move, especially with the magnetic jigs, and as a result your height will be off (probably too high). Some times you can wedge in shims to lock it at TDC or put clamps on the motor belt. Whatever works, try it. For my jointer, taking off the fence made this much easier to do.

[George Brown]

I use a jig that rests on the knife holding cylinder directly, so TDC is not an issue. I turn the adjusting screws until the blade just touches the jig.

[Kyle Iwamoto]

I use a cheapo device called teh Jointer Pal. Check Amazon. There are various priced versions. I have the cheapest version. There are some 1 & 2 star reviews, but both of those refer to a non locking cutterhead. Now I personally don't understand how that relates to the jig, but that's someone else's opinion. It's not a hi tech super accurate tool, but neither is the price. You can get better but you pay for what you get. For less than 40 bucks I think it's a great deal. Similar to the magnet/glass idea. But since it's on plastic sticks, you can easily tighten the blades with the jig in place. I got mine a LONG time ago for 20 bucks.

Just my 2 cents.

[Dennis Lopeman]

I found TDC... man... it's simply the highest point on the the cutter head!! Which is obviously the same around the whole cutter head b/c it's round... darn near perfectly (right!)... why didn't someone say that!!??! LOL

Joking - I probably missed someone stating that.

Anyway.. my jig board magnets did the trick. I tested and I got a nearly smooth surface... way better than I had using another trick I tried last night... Still a slight ripple.

Now I'm going to build the Swenson Jig using glass. I have rare earth magnets I took out of some old PC Hard drives. I have glass.

Tomorrow - re-allign the blades and obtain perfection!!!

[Paul Hingco]

I don't really have to set the height for my planer knives. I only have to match the holes of the knives with the tabs on the planer head.

For the jointer, the easiest method I've found is using a Jointer Pal in conjunction with a Dial Indicator.

http://www.youtube.com/watch?v=2UPXuGm7-2w


Others swear by the stick method. For kicks I sometimes use it to triple check my knives are set properly.

[Chris Parks]

I found TDC... man... it's simply the highest point on the the cutter head!! Which is obviously the same around the whole cutter head b/c it's round... darn near perfectly (right!)... why didn't someone say that!!??! LOL

Joking - I probably missed someone stating that.



No, it is the highest point of the blades, a big difference.

[Charles Cannon]

No, it is the highest point of the blades, a big difference.

Shouldn't the Highest point of the head also be the highest arc of the knives?
Cannon

[Chris Parks]

I presume the head is truly circular and has no one point higher than the other, in that case the blade has to be plotted to TDC. I don't know why manufacturers don't reference TDC as it would be easy enough to do.

[Myk Rian]

Shouldn't the Highest point of the head also be the highest arc of the knives?
Cannon
Yes. Once you have TDC of the head, TDC of the blades is the same.

[Chris Parks]

TDC as a reference in planers or jointers is actually as many points as there are blades. In other words you have to know TDC at each blade to set the height to the table. of course if you don't set to the table you don't need TDC just a measurement off the head that is exactly the same for each blade. A truly circular drum WILL NOT HAVE A TDC.

[Dennis Lopeman]

I'm in the camp that the head (being a near perfect circle, round, etc) has it's TDC at its "highest point"... Basic geometry, right?

Draw a perfect circle. Draw a perfect line and butt it up against the circle. Mathematically, it will only touch in ONE point on the circle. To the naked eye, of course, that looks much wider.

Now, with that in mind, you know you want the blades to stick out to the same height all the way around. I think that if you pick one exact place at each entry point of the blade, or the tip of the blade, or anything... just doing the same for each blade will make them all stick out the same distance. But we want to pick the TDC because we don't want the tip of the blade to stick out higher the the outfeed table!!

So I found a video: http://lumberjocks.com/GarageWoodworks/blog/14488

Seeing it was helpful. Using this method (I have a digital dial which actually makes it a little harder!) he shows finds the TDC, which obviously is also the very middle of the arbor, head and all.

So I feel confident that TDC is also the first point a straight edge would touch on the head if it were resting on the outfeed, lowering the outfeed until the straightedge touches the head. right were it touches is the TDC. And therefore, in quotes, that is the "highest" point on the head. (in quotes because that is in reference to the OUTFEED table.)

More geometry will also show you if you were to draw a line coming down from that TDC and straight edge, pass the line right through the very center of the circle (the arbor's center), then THAT line would be exactly 90 degrees perpendicular to the straight edge.

So I would also then deduce that I could find TDC with a sqaure, if I were able to hang it over the outfeed table and pass the other leg over the exposed arbor (on my jointer (Delta DJ15) I can actually see the arbor end) - I would just need something on my outfeed table to make it stick out so the square could align along the arbor - perhaps my glass Swenson Jig!!! :D - funny that the piece of glass that I have is much wider than my 6" table. I'll try it tonight and see how close last night's TDC finding is.

[Jim Andrew]

About 35 years ago in an earlier life, I did a couple years as a woodworking teacher. The school had a 8" powermatic jointer, and they had the powermatic knife adjustment tool. It was a gadget that sat on the table, and you just used an allen wrench to adjust the knife up or down and the gadget had a gauge which you used to set the blades. Much easier than anything else I've seen. Could replace the blades in 5 minutes before school started.

[Jason White]

Forget the magnetic jig for the jointer. I have the shop fox one. Total waste of money. A good straightedge and a little patience is all you need.

Jason



I'm trying to decide which planer and jointer knives setting jigs to buy. Any recommendations?

[Dennis Lopeman]

I gotta tell you - I made the glass Swenson Jig last week. Using that and TDC (top dead center, for those who don't wanna read this whole thread! ;) ) I am able to VERY EASILY set the knives and I get an ALMOST perfectly smooth surface on wood I run through. All I have to do is take it over to my sanding station - and about 4 swipes it's perfect.

(the "Sanding Station" is just 12" lamineted/self glue discs and/or 12" paper glued to my RAS table. I have a 120, 220, and 320 grit - makes sanding by hand so much easier - I got the idea from the Scary Sharp system)