Replies

1. 
   ring | Feb 16, 2010 01:38am | #1

   1. Sharp new blade

   2. Knife both sides of the kerf before you cut.

2. 
   woodhacker | Feb 16, 2010 08:44am | #2

   set the depth of cut for your circular saw to about 1/16" and make a scoring cut from the back side of the blade. You might want to make a second scoring cut with a slightly deeper depth of cut.

1. 
   SARGEgrinder47 | Feb 16, 2010 10:19am | #3

   You pretty much have answers at this point.. I also score it as mentioned with a razor knife on both sides then add painters tape over the score.

2. 
   morty | Feb 16, 2010 01:17pm | #4

   Thanks for your input. But, I don't know what "the back side of the blade" means.

   Morty

3. 
   gdblake | Feb 16, 2010 01:27pm | #5

   Morty:

   I think he means flip the blade around so that instead of the teeth functioning normally and lifting the fibers up as they cut the back side of the teeth will mostly push the fibers down with more of a scraping action. The idea is to score the wood before making a regular cut. I have heard of this approach before, but have never tried it myself.

   gdblake

4. 
   bones | Feb 16, 2010 03:31pm | #6

   Well you could use the Festool TS55 and the issue is moot. However another much less expensive choice is what I used prior to the TS55. I purchased a Forrest 7 1/4" blade for my PC CS saw and it worked like a charm. It made a beaut of a cut. I still have it and have not used it since the festool purchase.

5. 
   spotcheck | Feb 16, 2010 05:28pm | #7

   Sorry, but - good side down when you cut with a circular saw, plus the tape (on the down side at least, or on both sides) for added protection. Or - you've got what you're gonna get - that might be OK enough for you. But - with all the effort you've put in, I'd get some help to flip it over if it were me. Freshley sharpened blade.....

   Good Luck!!

6. 
   sapwood | Feb 16, 2010 11:29pm | #8

   Tearout cannot be helped when cutting with a circular saw. Measures can be taken to stop the the tearout, but they won't eliminate it. Ring gave you the best solution, score the cut with a sharp knife and cut wide of that. Then finish the cut with a router fitted with a trimmer bit and a full size template. You'll have to use the router both from above and below to assure that you'll be cutting with the grain. 

   But I wonder, how you plan to follow an elliptical line with a circular saw.

7. 
   joinerswork | Feb 17, 2010 01:38pm | #9

   morty,

   I hope you haven't glued a 5' wide tabletop to a plywood substrate.  If you have, cutting it into 3 pieces is the least of your problems.

   Ray

8. 
   joinerswork | Feb 17, 2010 07:40pm | #10

   Very good, Morty, carry on. ;-))

   Had me worried there for a minute.

   Ray

9. 
   jonnieboy | Feb 17, 2010 10:47pm | #11

   Morty,

   I'm sure others here will know the answer to this question, or will have tried it themselves. It goes right along with your question morty, I hope.

   The latest issue of FWW has an article on getting clean cuts. It got me thinking about tear-out with circular saws.

   I haven't had a chance to try this yet, but why couldn't one attach a piece of whatever to the bottom plate of the circular saw, then lower the blade (carefully!) through it. That should make a zero-clearance notch, shouldn't it? 

   It sounds too good to be true...

   --jonnieboy

1. 
   sapwood | Feb 18, 2010 11:45am | #12

   Good idea. I'd try mdf. Don't change to a shallow depth of cut afterwards.

1. 
   jonnieboy | Feb 18, 2010 11:48am | #13

   Sapwood,

   Right.

10. 
    jonnieboy | Feb 18, 2010 02:30pm | #14

    Comment deleted

1. 
   jonnieboy | Feb 18, 2010 02:39pm | #15

   Mort,

   I just tried the zero-clearance plate idea on the bottom of the circular saw.

   Long story short, it works pretty well as far as tear-out goes,  BUT IT DEFEATS THE GUARD!

   Even if one avoids a skin-to-blade accident, the likelihood of completing the cut, then setting the spinning blade on the floor (concrete in my case) isn't worth the risk. 

   Accident waiting to happen. Can't recommend it.

   Darn. There's always some little flaw in my million-dollar ideas.

   --jonnieboy

11. 
    wotnow | Feb 18, 2010 07:03pm | #16

    Hi Morty

    Was faced with a similar situation. the timber almost chipped just looking at it.

    I sorted my problem by gluing a 3/16" by 4" lath along where I was going to cut. When it was well and truely attached and dry I cut along the lath through the lot, planed the lath remains down as far as I could and sanded down the rest. It worked perfectly for me.

    wot