Replies

1. 
   forestgirl | Apr 07, 2004 03:48am | #1

   Sounds like a table-adjustment thing maybe.  Have you triple-checked that your outfeed table is dead-on with the edge of the knives at the top of their arc?  (Or, according to some, a micro-smidge lower than the knives).  Are all the knives the exact same height (probably, since you didn't say your cuts were ugly; just checking).

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
   Another proud member of the  "I Rocked With ToolDoc Club" .... :>) 

1. 
   woodman54 | Apr 07, 2004 04:59am | #2

   The jointer was set up perfect by Grizzly as far as the knifes and  outfeed table is concerned. I can adjust and repair all the other tools in my shop except the jointer which is new to me. I guess I will have to figure out that coplanar thing.  

1. 
   rod | Apr 07, 2004 05:46am | #3

   About a month ago, there was a very good posting on how to set the outfeed table. I used it and it worked wonders.  Try to find it in the archives.  It went like this: purposefully set the outfeed table low.  Have two boards that are about 2/3 the length of the jointer tables, already pretty flat and one edge square.  Joint one face on each board and place the jointed faces together.  You should see some snipe and a convex gap in the center of the two boards.  Raise the outfeed table a tad and re-joint the faces.  Continue this process until the snipe goes away and the gap in the center goes away.  When this happens the outfeed table is set correctly.  I think the posting said it was good to use the same kind of wood you would be wanting to joint for the project.   I can say it worked for me.   The original would probably be more clear in its directions.

   Rod

1. 
   woodman54 | Apr 07, 2004 12:42pm | #5

   Well that sounds easy enough, I will try it when I get back in the shop.

1. 
   Tao | Apr 07, 2004 06:34pm | #6

   That's a good method.  Another one is to lower the outfeed table then raise it until the knife drags a piece of wood about 1/8" as it passes under the wood with you turning the cutterhead manually.

   I use that to get started and then check by running boards and making fine adjustments until they match perfectly.  If set up properly, you won't even see a black line where the pieces mate on shorter pieces.

   The reason the knives have to be a skosh higher than the outfeed table is that the wood is compressed by the knives as they cut, and it springs back a little after the knife goes by.  At least that was what I was taught in machine tools class years ago.

   Michael R

2. 
   tsproul | Apr 07, 2004 06:58am | #4

   yup...I concur.

   set the outfeed low....joint a piece...though ime, it need not be perfectly straight - use a straight edge cutting guide and circular saw to make straight edges.

   raise the outfeed 'til you get a straight/flat edge.

   you're problem sounds just like mine when I started using a power jointer.  I set the outfeed exactly even with top-dead center (TDC) of jointer knives...then would joint a crook with edges proud of center when edging or a taper when face jointing.  lowering the outfeed a "smidge" solved my problem.  Since you're already close, just try lowering the outfeed a wee bit....and a wee bit more if the problem gets better but not resolved.  Obviously, try going the other way if the problem worsens...

   Tim
3. 
   mlbfreestyle | Apr 08, 2004 12:40am | #7

   I have gone through the same problem.  Adjustment, as outlined in some of the replies is important.  Technique will also affect the cut.  Here is my method.

   Start with the stock just ready to hit the cutter head.  My hand is putting downward pressure at a point near the leading end of the fence.  That hand then travels past the cutter head until it is at the trailing end of the fence.  I then go hand-over-hand at that same point until the stock is past the cutter head.

   The bottom line here is that if you put too much pressure at the wrong point along the length of the board, you will accentuate any tendency to cut a convex edge.

   I adjust my outfeed table upward until I feel drag as the stock passes over it.  I then back it off ever so slightly.  It takes some fiddling.