Replies

1. 
   hammer1 | Sep 21, 2010 09:50am | #1

   Since that style of bit removes the entire face of the work piece, you need an off set outfeed fence similar to the way a jointer works. In these type of cuts, a stock feeder is pretty handy. They give a steady and even feed. A horizontal router table would allow you to feed the work flat to the table, rather than up against a fence on edge. You need to add shims on the outfeed side to support the work. Final pass should be much less than 1/16".

   Your infeed feather board should not be pressing directly against the bit. You may want to make a thicker one or pile a couple thin ones up to fully support the width of the work. If you provide shims or an off set outfeed fence, you could use feather boards on the outfeed side, too. Anything to keep the work from vibrating. Consistent, steady feed is also important. Try to find the "sweet" combination of feed, bit speed and depth of cut.

   
2. 
   RalphBarker | Sep 22, 2010 11:56am | #2

   ch-ch-chatter

   I agree with Hamemr's suggestions. It is also possible that some of the chatter is originating with vibration of the table while making the cuts. Without firm support of the workpiece on both sides of the cut, any vibration will likely be magnified..It's unclear from your photos how the table is supported.

1. 
   karlshikles | Sep 28, 2010 04:54pm | #3

   Router table...

   It's actually the extension table on my big 12" Grizzly tablesaw, so it's actually rock solid.  The 'fence' is slipped over the Saw's Biesemeyer fence to take advantage of the precision and stability of the rip fence.  There's a 2" dust port on the far end of the fence.  I actually went with a combination of two of Hamemr's suggestions:  I stacked two wider 3/4" featherboards and put them just before the bit, so virtually all of the 2" workpiece was supported.  The resulting pieces weren't exactly glass smooth, but I hand sanded out the minor chatter with some 320 grit.  It's worth noting that it was still smoother than that crap they sell at the box stores.  I'll have to figure out an efficient way to shim the outfeed table before my next project that requires such millwork.  I imagine this will take care of the last microscopic bit of 'chatter'. 

   Thanks again for your time, guys.  It's really appreciated.

   Karl

1. 
   RalphBarker | Sep 28, 2010 05:29pm | #4

   aux fence

   If the auxiliary fence is split (i.e. two sections that adjust away from the bit location), the easy way to shim is to slip paper behind the outfeed side.

3. 
   BruceS | Sep 29, 2010 06:40am | #5

   What I see

   I use about 8" of feather board on each side of the bit.

   But I think you biggest problem is inconsitent feed rate and probably too heavy of a cut,  especially on your final pass. With that sized bit I generally do about five passes, the last pass being just a kiss.

   Another trick I've used when using a bit like that  and running the piece vertically,  is to run stock that is 1/4" wider than needed and center the bit on that.   That leaves 1/8" top and bottom that can run on the fence, and no need for fancy shimming on the outfeed side.   Then just rip off the unwanted support stock.

1. 
   karlshikles | Oct 05, 2010 03:06pm | #6

   Bruce,

   I actually really like that suggestion and am almost mad at myself for not thinking of it.  I'll definitely give that wider stock idea a try next time.  Sometimes the best ideas are the simplest - especially since you have to rip the stock to get the spring angle after shaping it anyway.  Thanks!

1. 
   BruceS | Oct 05, 2010 05:04pm | #7

   Outfeed frustration

   I actually stumbled onto that trick when routing out a bunch of stock for picture frames.   It was one of those duuhhh stupid me moments,  why not try wider stock and rip it.  BINGO.