Replies

1. 
   knuts | Mar 22, 2009 03:20pm | #1

   Not really sure what you're asking. Maybe you could be more specific. However, I use upcut spiral bits in my Woodrat for mortising because they plunge well, leave smooth sides and pull the chips up for the DC.

1. 
   tom_47 | Mar 22, 2009 06:23pm | #2

   Knuts,
   I'm using a Woodrat too.
   More specifically my question has to do with whether the majority of wood is removed through "boring" or "sliding" - i.e. are a series of bore holes made across the whole face of the mortise and then the mortise finished by a single "slide" of the bit across its length OR is a single bore hole made and then the bit slid across the face to form the mortise. Also, how deep should each pass be ? I'm using maple and my mortises will be 1.25" deep.Tom

1. 
   Wingdoctor | Mar 22, 2009 07:43pm | #3

   Normally you make full mortise width passes at incremental, 1/8" or so, depth until you get to the full depth of the mortise. This reduces the strain on the bit and gives a smooth, consistent cut. Using a plunge router with the depth stop set to full depth, make a pass at 1/8" or so depth, drop the bit a little deeper, repeat until full depth.

   Bruce"A man's got to know his limitations." Dirty Harry Calahan

1. 
   tom_47 | Mar 22, 2009 08:11pm | #6

   Wingdoctor,
   Thanks.
   Tom

2. 
   knuts | Mar 22, 2009 08:16pm | #7

   I plunge the 2 end holes, remove the stop block, raise the bit and run the router back and forth while lowering the bit as I slide. The zigging and zagging is really fast and you get a 'feel' for how far to lower as you go. Then I'll do a full depth sweep to clean it all out. The full hole at the rear keeps me from overshooting the mortise lenght. Takes about 8-10 seconds.

1. 
   tom_47 | Mar 23, 2009 12:18am | #8

   Knuts,
   Just to insure I've got this right: You plunge the the full depth at both ends then zig/zag between the two (using the slider (east/west), increasing the depth (say 1/8" per pass) till you bottom out.
   Why do you bother removing the stop blocks ? I'm assuming you have them mounted in the left hand clamp and they're not in the way of the quick zig/zag motion. Also they would be ready for successive pieces, no ??
   OR, are you holding the work oriented north/south and sliding the router forward and back ? This is my first project using the rat.Tom

   Edited 3/22/2009 5:19 pm ET by Tom from Owego

1. 
   knuts | Mar 23, 2009 12:30am | #9

   OR, are you holding the work oriented north/south and sliding the router forward and back ?

    

   That's right. I do mount an E/W stop to make quick work of centering/aligning the work piece. But I mortise N/S whenever possible. You need the miter clamp or something close to do  this on legs etc. Great little pdf file from one of the guys on the Woodrat forum for making you own work holder. I'll take a pic of mine if you like; just let me know.

2. 
   tom_47 | Mar 23, 2009 05:43am | #11

   Knuts,
   The slop in the router-plate/base-plate slides isn't much but it's more than the slider, so I assumed locking the router (and sliding the fence east/west) would yield better width precision. I would like to see that miter jig.Tom

3. 
   knuts | Mar 23, 2009 04:23pm | #12

   I use speed nuts on threaded rod and little ledger strips to keep the holder in the clamps to speed things up. Just noticed you can't see the workpiece, but it's 1" wide. I agree with your comment re router plate slop but it's not perceptable on my unit. Also attached a pic of my indexing block with magnets since it was still mounted.

   View Image

   View Image

    

    

    

    

    

4. 
   tom_47 | Mar 23, 2009 09:25pm | #13

   K,
   Thanks.
   T

2. 
   Routerman | Mar 22, 2009 07:47pm | #4

   Some data on morticing with a router.

    

   And for some precautions with spirals see no.12.

1. 
   tom_47 | Mar 22, 2009 08:10pm | #5

   Routerman,
   Thanks.
   Tom

3. 
   robkress | Mar 23, 2009 03:24am | #10

   I'm one of those idiots who strives for perfection. So I do my mortises in a two step process. Basically, I use any old bit for the first pass at the mortise. The key is, I use one size down. Then when all the material is gone, I go back and put in the right size bit and take one nice, easy, even, clean cut, full depth (with a little extra off the bottom).

   This produces absolutely at size mortises without variability. And since I have worked out this method and do a lot of work on my router table, it doesn't take me that much time to do the extra bit change and setup. Really pretty easy.

   No need for a fancy up cut bit. In fact, I go to my local machine tool store (know those guys well) and buy full carbide 4 flute end mills for a fraction of the stuff online. Great quality.

   Rob Kress

4. 
   BrianDerr | Mar 25, 2009 08:59am | #14

   Last time I tried that was on the router table (move the board from right to left), and found that my lower quality straight bit gave a much cleaner cut than the newer, solid carbide spiral upcut bit. But most importantly, I had confidence with the straight bit--the spiral felt very jerky, almost to the point of being unsafe. Maybe becuause every time it cuts it increased the tension between board and table, which makes physics want to stop the cut. But you are still pushing so it eventually jerks forward in a less controlled motion, hence the jerky feel. Maybe with a handheld router the upcuts are more appropriate, but I really can't say.

   Brian