Setting Jointer Knives Dilema

[Orlando Gonzalez]

I have restored a PM 50 I got from CL and need some advice. I replaced the cutterhead bearings and bought new blades. But I'm going nuts trying to set the knives. I've tried so many different methods (John White's, JointerPals, the stick method, Bob Vaughn's) but I still can't get them set right (I probably need to buy Jointer Knife Setting For Idiots). http://www.forums.woodnet.net/ubbthreads/images/graemlins/yellowupset.gif http://www.forums.woodnet.net/ubbthreads/images/graemlins/yellowsigh.gif

I don't see myself upgrading to an 8" or bigger for the next 2-3 years, since I don't have the space, or a shop for all that matters (I'm using my terrace to the chagrin of SWMBO), so it will be my #1 jointer for some time. So do I go for the gusto and get the Byrd Shelix or do I keep trying to set the kinves and get no work done?

Thanks

Orlando

[Chris Parks]

What is the problem exactly, setting the height or is something stopping you setting the height properly?

[Orlando Gonzalez]

Exactly. I'm getting inconsistent height between the knives using the stick method. One knife will be right on, but then I can't get the other knife to set up the same way. It has been a real frustrating task. I've been working on it all day with no luck.

[Jim Becker]

Another question....springs or jack screws?

[Orlando Gonzalez]

Jim, it has jack screws. Right now I'm looking at Bob Vaughn's video for the umpteenth time trying to get it into my thick skull.:)

[Faust M. Ruggiero]

Orlando,
Setting jointer blades and getting good results takes time and practice. Even the jigs don't make it fool proof and I actually find them difficult. Let's go a step at a time. First check your new blades. Lay them edge to edge on a clean piece of paper and be sure there are no gaps. Once you're satisfied they are properly sharpened, take a felt tip pen and mark the slots #1 through #3. You want to be sure which was your first blade and therefore your standard. Clean the gibs and slots. Smooth any burrs with emery cloth. If you have height adjusting screws on the cutter head, lower them all the way. Set your in feed table about 1/32 lower than the out feed table. This is not a critical measurement at this time as long as the infeed table is lower than the outfeed side. Once you set it don't move it again until you have finished setting all three blades. Your goal will be to set all three blades the same height side to side and to each other using the out feed table as a reference. Now, find yourself a perfectly straight metal straight edge. Nothing too heavy or wide. We don't want to bugger the edges. I use a Starrett 12" steel ruler from a combination square. I don't believe a "stick of wood" no matter how true is suitable for this part of the job. After inserting the first blade and tightening the locking screws just tight enough to keep it from moving easily, use the adjusting screws to elevate both sides of the blade ever so slightly above the out feed table. I set the ruler on edge and allow 1/3 of it to overhang the cutter head. I set the blades so that when I turn the cutterhead by hand, the ruler moves 1/8". That's easy to see because you are using a scale. Don't leave the first blade until it is perfect and fully tightened. Note whether the blade changes height when you final tighten it. If so, allow for it. After all three blades are perfect, you can adjust the final height of your out feed table. If you leave the table too low, you will get snipe. Too high will cause your piece to be convex. Be patient and view it as a challenge. The effort will be worth the work. Square and true cannot be underestimated.
Faust Ruggiero

[Orlando Gonzalez]

Thanks Faust. The jack screws!!! :eek: http://www.forums.woodnet.net/ubbthreads/images/graemlins/slap.gif I totally forgot about them. :o A couple of things:
1 - When you say to lower them all the way down that means that the set screw should be up and not screwed down into the jack screw?
2 - Would a dial indicator give the same results as the blade?
3 - What about TDC (Top Dead Center)? Do you find it or don't bother with it?

Thanks

Orlando

[Chris Parks]

About TDC, if you aren't referencing to the table you don't need it, if you are then I don't know how they reference it. My jointer has springs under the blades along with a curved jig and which measures both ends at once, it references the height straight off the drum to the cutting face of the blade. I would make one if it were me as it takes away the necessity of referencing to the table. Also mine has springs underneath it to push the blade against the jig, no measuring just do up the screws. Now I reckon if you made a jig like that and put some sponge rubber under the blades it would serve the same purpose and you could pull the sponge rubber out from the end of the drum. Mind you I don't know if I would even bother pulling it out, just leave it there. it weighs nothing and is so close to the centre of the drum that balance would not be a factor. By doing this you could ignore the height adjusters, even remove them altogether. I will now duck for cover as I know all this is heresy to the N'th degree. :eek::eek:

[Phil Thien]

(1) You can make this a lot easier by making a jig to hold your dial indicator. It is basically a block of wood with a flat bottom and a recess to allow clearance for the tip.

(2) Do not use a button tip, but rather a flat tip. Using a button tip requires that you align the top dead center of the knife with the bottom dead center of the tip. Just get a flat tip and only worry about top dead center of the knives.

Here is a link to a previous thread where I show my simple jig for setting the knives (not my original work, I copied it from some web site I saw):

http://www.sawmillcreek.org/showthread.php?t=60068

Scroll down to message #13 to see the jig (um, block of wood).

[Johnny Kleso]

I have a Tutorial on my website you can get to by clicking on my name..

I think it was the first WW webpage I made so its not the best but it is the best way to set knives..

[Chris Parks]

(1) You can make this a lot easier by making a jig to hold your dial indicator. It is basically a block of wood with a flat bottom and a recess to allow clearance for the tip.


Forget the DI and put a bolt in it, gee why do we have to complicate things? make two and one each end sets the same height off the drum. Put a rare earth magnet in each foot of the jig and it won't move at all. Spring load the blade to push against the bolt/stop and it takes 30 seconds flat to set blades. No guess work, reading DI's etc. I used to read about how difficult it was to set jointer knives, using the above method takes all the mumbo jumbo out of it.

[Joe Jensen]

With my jointer and planer, the knives would creep as I tighted the knives to lock them down. I developed a sense of how much they would move and I would account for this to determine the starting height before tightening. As I read this, it sounds hard to visualize. Take my planer, I would use a dial indicator to get say .002" away from my desired final dimension, and then as I tightened the screws, the knife would move into place. I had to determine this amount of creep through trial and error.

After 30 years of this, I ended up getting a Byrd head for the planer, and a terminus head for the jointer, (I am planning to switch the terminus for a Byrd).

Best wishes, and you will learn...joe

[Faust M. Ruggiero]

Orlando,
Keep the job simple. No dial indicator needed. This is low tech. Tighten the screws to allow the blade to be as low as possible. Set in the blade then use the screws to raise the blades to the desired height. Blades should always project from the cutter head as little as necessary. That keeps the jointer "quiet". It also gives max support to the blades. You don't need to locate top dead center. By laying the rule on the out feed table protruding over the cutting head, then slowly rotating the cutter head by hand TDC will tell you where it is. If if the ruler moves 1/8" as I suggested, TDC is half way through the movement. Just so the other two blades also move the ruler 1/8" on both sides, the blades are even.
Faust Ruggiero

[Jim Becker]

I will add that if there are three or more jack screws, adjust the two outside ones to get your height and then revisit the middle one(s) after the fact to bring them up to support the knife.

[Phil Thien]

Forget the DI and put a bolt in it, gee why do we have to complicate things?

Cause knives aren't typically sharpened perfectly straight (they often have a smile or frown), and cause they move when you tighten them. The DI tells you where you are across the entire knife, no guessing.

[Orlando Gonzalez]

Thanks for all the replies and suggestions. I will try to set the knives using one method or another until I get it right.

Again thanks for the help. I really appreciate it.

Orlando

[Orlando Gonzalez]

After 6hrs I could only get one knife aligned. When I went to knife #2 I set one side then went to the other and got it set. When I went back to check the first side again it had moved up. I was using both the stick and the blade methods. Tried the dial in dicator method with the MultiGage and that was a fiasco. Zeroed out dial on outfeed table, checked TDC a la Bob Vaughn method, replayed his video especially the part on jonters with jack screws, that was a no go. I checked with the original manual on their recommendations - snug both end screws then adjust knife with jack screws - well one side went up and the other went down like a seesaw in a playground. :confused: :mad: Byrd Shelix will be here next week. I hope it takes me less time than this futile effort on my part.:) I already have the cutterhead off and will pull the bearings tomorrow. And just to make things worse, three holes in the angle bracket on my Biese did not line with the tube. Had to widen them by 3/32.:mad: What a day.

Thanks for all the suggestions. The failure was purely mine.

Orlando

[Shannon Seelig]

I remember reading a thread that was posted about a glass plate and earth magnets. The glass was put on the outfeed table with magnets glued to the top of the glass on each end. The jointer knives would stay alligned because they were stuck to the magnet. The glass plate would stay in place because the magnets held it to the outfeed table. Was this a good method or was this a questionable way to set the knives?? I haven't changed my jointer knives yet, but that was the way I intended to when the time came to put new ones in. Any thoughts???

[Shannon Seelig]

I just did a search on past threads and the method I was referring to was Per Swenson's method for changing jointer knives. I thought it looked like a slick and quick way to change the knives. Any thoughts?

[Orlando Gonzalez]

Give it a shot. Conceptually it is the same principle as the Jointer Pal and Magna Set. I have the Jointer Pal and I was unable to set the knives. But I can't set them even if they came indexed.