Cutting Cabinet Plywood with 7 Circular Saw

I usually make crosscuts of cabinet grade plywood, which are too large for my tablesaw, with my 7 " circular saw. To avoid chipping the finished piece I make the first cut a little long. I also always cover the cut with masking tape, but still get some chipping. I then cut to the exact size using a straight cutting bit with my router. Using the router leaves a perfect cut, but I have a project coming up that doesn't leave any room for an oversize cut unless I go to a second sheet of plywood.
Does anyone have any suggestions for cross cutting cabinet grade plywood with a circular saw that eliminates chipping? I have tried different blades, and cutting heights, but so far the best that I can get is about 95%. That other 5% can be a killer.
Bob McBreen
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RWM wrote:

I have read that the Festool saws do well. http://www.festool-usa.com/portando/index.cfm
Additionally, I've read that cutting first with a utility knife can get rid of chipout.
Disclaimer: I've never tried either solution.
-- Mark
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P.S. I also recall reading about "zero-clearance insert" for a circular saw.
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I recently posted about using masonite and polyu glue for this. Not really and insert but another layer on the foot. I notched the leading edge with respect to blade kerf.
On Tue, 04 Nov 2003 02:06:42 GMT, "Mark Jerde"

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On 8 Nov 2003 12:00:36 -0800, Christian Aufreiter

I made the panel-cutting guide found in Sunset Woodworking (forget the exact title). After sizing sheet goods with a 9" contractor saw, it was a revelation.
It uses Borg Birch plywood instead of masonite.
I've been planning to make a smaller version suitable for half and quarter sheets. After reading the article, I'm now planning to use masonite for the smaller version.
I'm using the Freud "Finishing" blade (40T ATB, thin kerf) on a PC lefty circular saw.
With patience, it's more than Good Enough absent a Unisaur or a dedicated panel slicer.
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I just made 20+ linear feet of cuts on cherry veneer plywood with a Black and Decker circ saw with a new Oldham 60-tooth carbide-tipped, 7-1/4" blade, with the good side face-down. The cuts were very clean with virtually no chip-out. The cuts were good enough to use in my house, I'm not sure how that translates into "professional use".
-JBB

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Sandwitch it between a couple of sacrifical scrap.
1/4" masonite works fine.
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I used polyu glue for 1/8" masonite on bottom as zeroclearance. Major difference.

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Freud has a 40 tooth carbide 7 1/4" blade that does pretty well. I use it on a PC saw for cut off's and plywood cuts that I can't make on the table saw. Face side down on a circular saw, face side up on the table saw. and score the veneer with a utility knife.

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I have had good luck by making a scoring cut with the saw. I set the cut to about 1/8" and then run the saw backwards across the plywood. Since, you are making a very shallow cut, there is very little tendency for the saw to climb out of control but keep a good grip on it. Then reset the saw for full depth and make a regular cut.
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