A thought on setting jointer knives

[Andrew Fleck]

As I was setting my new jointer knives tonight I had an idea. My usual method is to reference them off of the outfeed table using a dial indicator. This works well, but it is tedious. I don't like the back and forth from the fence side to the rabbeting side tightening and loosening gib bolts while I get the knives just right. I have always done it this way and it has always worked.

My thought is to get some bar magnets. Maybe some 4 or 5" long ones that I can attach to the outfeed table and extend over the cutterhead. It seems like they should hold the jointer knife flush with the outfeed table while I tighten the gibs up.

Has anybody tried this or maybe tell me some flaw with it that I can't see? I should add that this is a 15" cutterhead without jack screws which makes things a bit painful when setting knives.

[Andrew Hughes]

I have seen at least one you tube video that that way.Was going to try it myself but could not figure out how top dead center is found without a knive to reference from?
i use a dial indicater with a flat pad on the bottom and go back and forth my jointer has no jack screws to lift the 12 inch knive.
Good luck hope you can get it to work.

[joe milana]

Here's a YouTube video using rare earth magnets: http://www.youtube.com/watch?v=TrQBQfs3HZk

[glenn bradley]

Back when I had a knifed machine I used a piece of plate glass and rare earth magnets. Worked like a charm.

277221

[Art Mann]

Such jigs are commercially available. See here as an example: http://www.rockler.com/rockler-magnetic-jointer-jig

[Chris Fournier]

The force of the gib screws easily over powers the force of the magnets, rare earth or not. Your indicator is reliable.

[Ed Aumiller]

I have the rig like the link... it is a different name, but same thing..
It is ok to get them close, but to do a good job, you need to finish them with a dial indicator..

[Larry Fox]

I use a Oneway Multi Gauge and it works well and moves easily. If I didn't have that I would just get two dial indicators so I didn't need to move them. Regardless of the method I really don't like doing that job and am glad I don't have to do it very often.

[Metod Alif]

I had a Delta 8" for over 20 years, and never used a dial indicator to set up the knives. Also on my thickness planer. The machine marks from both are still even and faint. For the jointer, I only need a block of wood to hold down the (spring-loaded) knives while I tighten them. My Delta planer came with a saddle type setting gauge that is used to hold down the knives. I did need to fine tune it for 'more' parallel cutting. It holds the setting just fine.
I need glasses because of poor eyesight, but they are not needed by everyone. If one has poor 'whatever' for a dial indicator, that's her or his own situation. It is probably easier to buy an indicator than to develop suitable skills.
Metod

[Rich Riddle]

I use the Big Horn 19612 with magnets. Amazon sells it here:

http://www.amazon.com/gp/product/B001DDWQQE/ref=ox_ya_os_product

[Chris Parks]

Machine the end of the screws flat and the blades won't move much if at all.

[Michael Dunn]

For years I've used the jointer pal. I recently acquired the One Way Multigauge.

My tip is for after you've set the knives. I've read that setting the knives to be dead even with the outfeed table. I've also read that some will then drop the outfeed by a few thousandths of an inch. I did that for the first time the other day and it seems the boards just glide over the table now. I've always waxed my CI tops, but this really helped my jointer. Wow! Night and day.

Give it a shot.

[Andrew Fleck]

Back when I had a knifed machine I used a piece of plate glass and rare earth magnets. Worked like a charm.

277221

That looks like it should work. Thanks for the tip. I will try that if my bar magnets don't work.

[Andrew Fleck]

For years I've used the jointer pal. I recently acquired the One Way Multigauge.

My tip is for after you've set the knives. I've read that setting the knives to be dead even with the outfeed table. I've also read that some will then drop the outfeed by a few thousandths of an inch. I did that for the first time the other day and it seems the boards just glide over the table now. I've always waxed my CI tops, but this really helped my jointer. Wow! Night and day.

Give it a shot.

I have dropped my outfeed table like you said in the past. That always resulted in a little bit of snipe. There wasn't really much, but just enough to annoy me.

[Andrew Fleck]

I'm going to order some heavy duty magnets over Christmas and give my idea a try. If it doesn't work I can always find a use for some extra magnets. I will let you guys know how it works out after the holidays. Thanks for all of the replies.

[Matthew Hills]

For years I've used the jointer pal. I recently acquired the One Way Multigauge.

My tip is for after you've set the knives. I've read that setting the knives to be dead even with the outfeed table. I've also read that some will then drop the outfeed by a few thousandths of an inch. I did that for the first time the other day and it seems the boards just glide over the table now. I've always waxed my CI tops, but this really helped my jointer. Wow! Night and day.

Give it a shot.

I'd read to set my knives just a little above the out feed table. I don't do this by setting them even, then adjusting -- I set a small block of wood on the out feed table, extending over the knife. I want turning the cutter head to just barely brush the block of wood and move it. I adjust the knife to give a consistent amount of movement across the width of the knife. (I forget how much movement I was tuning for -- need to do it again soon)

I don't notice any snipe from this -- either with raking light or by feel. Expect I'd see some if the blades were set too high.

I've also got a oneway. Find it useful when I'm having problems getting things dialed in and I want to measure how much the screw is moving my knife.

Matt

[Joe Jensen]

I've gone through jigs and magnets, dial indicators, etc. Lots of money wasted. In my experience "THE" easiest way and the method that gives me the best results is to use a scrap with a flat edge, maybe 12-16" long. I rest the scrap on the outfeed table with it resting on a knife about 1" in from the end of the board. I place a mark on the scrap at edge of the outfeed table. Then I rock the cutterhead back and forth. When the knife is higher than the outfeed table the knife will grab the scrap and move it. I shoot for just high enough to drag the scrap back and forth 1/8" total. I haven't done the geometry but this method seems the be very sensitive and I suspect it delivers less than .001" accuracy. I just move the scrap to each and of the knives and adjust. As others have said, the gib screws will move the knife a ton and in my experience they easily move the magnet based jigs. For those using magnet jigs, I am curious what you see with the method above? Does it move the scrap consistently for each knife and across each knife? If yes then the jig works fabulously and please report back.

[Craig Behnke]

i used that method when i had to set jointer knives but regular magnets didn't work well, they were pretty weak. i used rare earth magnets on the jig, those are much stronger and the jig worked great. very similar to Glenn Bradley's jig. was much cheaper than the store bought jigs and worked great.

[Mel Fulks]

Since you ask ,I've seen this type of method reccommended a number of times . In my experience it leaves the out feed table slightly low,one thousandth can make a difference either way. When the out feed table is low ,many are happy because material will not "climb". But what does happen is it produces joints a little open at ends . Most don't care as they find that less troublesome than ,"Hey, I needed to take off exactly 1/8 and the machine took off more at the front than the back ,WHATS WRONG WITH THIS THING !? ". And the I think the often heard "works well with out feed table 2 thousandths lower than knives " proves my theory.

['Jacques Malan']

We also use a variation of the plate glass idea, we have a hole tapped into the outfeed table, and a board that is bolted down. There is a little reference mark on the side of the board, the cutter is held in place with a wedge and we lift the blade until it touches the board. Takes about 15 minutes for the 6" jointer (3 blades) and 25 minutes for the 12" jointer (4 blades).

After replacing the blades the outfeed table is set up with two pieces of wood, fiddling around until there is no gap when the edges are held together.

[Mel Fulks]

[QUOTE='Jacques Malan'

After replacing the blades the outfeed table is set up with two pieces of wood, fiddling around until there is no gap when the edges are held together.[/QUOTE]
Yes , a most important step that more often than not is omitted.

[Jeff Duncan]

I always find it funny that so many jigs have been invented and sold for something that is so simple. I know a lot of guys still like to use the dial indicator as well, though it seems as though it would be clunky at best. I use the "stick method" and have since I first started using a jointer some 20 years ago. It's simple, requires no expense out of pocket, and is as accurate as you'll need for setting jointer knives. Anything else is just monkeying around trying to invent a better mousetrap IMHO;)

but hey….to each their own!
JeffD

[Andrew Hughes]

I'm surprised no one with one of those fancy shamancy European jointers hasn't chimed in to tell how easy it is to change knives in their machine.Maybe they will when their done holding their stomach and laughing.you know the ones with their M1000 super steel two sided blades.:D
After Andrew gets his jointer knives set I think we should start a discussion on how to sharpen your knives and balance them I got a great jig.

[Mel Fulks]

IMO the old jointers with the indexing wheel feature has never been matched. With a home made magnet gig they are most accurate . I improved on one by putting calibration marks and a pointer on out feed adjustment wheel . Had a mark to use while installing the knives and another mark to raise table back. Never needed more than the slightest up adj, when doing the nessecesary two board edges touching test. A great design.

[Andrew Hughes]

Mel are you talking about the indexing hole on user side of the head that my oliver has? I was thinking if that would help to find TDC.I did find a pin to fit very nicely,but still off maybe due to my knives are too thick 5/32 longer bevel.

[Kevin Jenness]

For standard gibbed knives I find the straightedge method most useful- if the cutterhead carries the straightedge between 1/16" and 1/8" at at 3 points on all the knives they will be +/- .001" of each other and just above the outfeed table. At that point, I do a test cut with two boards as long as the outfeed table and adjust it as necessary. I work with a Tersa head jointer, and it too needs that final adjustment to get it dialed in. Less than .001" in outfeed table height can make the difference between perfect and not good enough, and if the knives are not all in plane there will be sweet and sour spots across the table, insignificant for flattening but noticeable when edge jointing. As the knives wear, the table can be lowered slightly before the knives need changing again. It takes me about 45 minutes to an hour to do this on a 4 knife 16" jointer with old style knives and no jack screws, about 5 minutes on the Tersa head.

[Mel Fulks]

Andrew, I was referring to a three knife jointer with a cutter head shaft that goes through the bearing on the operator side. A wheel aprox 3 inches in diameter is bolted to the shaft . It has 3 holes in it . A tapered pin on a chain is used to go through the index wheel and into machine to lock the head firmly in place. The orientation of wheel to head can be set to operators liking . I set it to where the knife is exactly vertical while being installed. That means the out feed table is dropped at start of change to be level with top of knife. That's means that when all 3 knives have been changed the direction the table must go in is known ,UP. I then turned adj. wheel to a "zero" position indicated by a pointer bolted to machine until it is on a mark filed on edge of wheel. Then test joint a couple of boards to see if they fit together along entire length . Adjustment will be perfect or need a tiny movement up. Marks on edge of adj wheel are 3/8 inch apart and represent table movement of 2 thousandths. I'm an old guy working little now ,but I started working about 1966 and have used a number of good machines but that Faye and Egan jointer is the only one I've seen with that feature.

[Jim Foster]

I've tried a number of methods, including the magnetic bars. I think a long straight edge or flat ground stock on the out-feed table hanging over the cutter-head works best.

[John Downey]

I have a couple 8" sticks with 3 magnets let into each stick. As long as they are straight, it works way better and faster than a dial indicator. If your machine is old and has the little screw-lift things for the knives, replace them with springs for setting this way.

For the planer I do still use the dial indicator. Tedious but effective, and it ensures the knives are all parallel to the bed.