Replies

1. 
   JohnWW | Apr 14, 2004 05:44pm | #1

   ASK,

   The combination or the crosscut will most likely leave a smoother edge than the rip.  I'd take a test cut with both blades to see which leaves the better edge.  Most blades will leave some tearout on the bottom face, this can be minimized with a zero clearance insert provided the blade reaches to the front edge of the slot in the insert.  For the best possible cut, with minimal tearout, you can buy a veneer/laminate blade, they're commonly available.

   If you are getting top face tearout caused by the teeth on the rear of the blade brushing on the fence side of the kerf, your rip fence is toed in and needs to be adjusted.

   John W.

2. 
   charlesm | Apr 14, 2004 06:47pm | #2

   Choose an 80 tooth blade with HiATB grind and very low or negative hook angle. Freud version is item# F810.

   Charles M

   Freud, Inc.

1. 
   forestgirl | Apr 14, 2004 07:06pm | #4

   Hey, Charles, we were typing at the same time!  You're answer was much more concise than mine, though, eh???

   Question for you regarding hook angles.  I'm trying to learn what the different hook angles contribute to the cutting action of various blades, and I notice that the F80 has only a 2* hook (combined with HiATB).  How does that figure into things?  And then the 806 has a 15* hook on "flat" teeth.  Educate me, pleeeeeze?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. 
   charlesm | Apr 14, 2004 09:01pm | #6

   FG,

   Generally speaking the higher the hook angle the more aggressive the blade, the faster it cuts and less effort it requires to feed. The highest angles (greater than 15°) are used for ripping applications where there is less concern for chipping/tearout and more desire to feed quickly. The tooth grinds vary from flat to TCG to ATB but are mostly flat. The medium angle range of about 10° to 15° is best for crosscuts in solid woods and usually with ATB but some flat and TCG. The low and negative hook angle blades are for materials such as veneered plywood with the HiATB or laminates, plastics and nonferrous metals with TCG. The benefit of the low hook angle for plywood and laminates is that it doesn't tend to push too aggressively through the material so it is less likely to splinter/chip on the exit side of the cut.

   The TK806 has now been changed to all ATB but still has a 15° hook. It does very well in most plywood but can splinter the exit side veneer in some of the very thin, difficult to machine veneers.Charles M

   Freud, Inc.

3. 
   forestgirl | Apr 14, 2004 07:00pm | #3

   Eliminate the rip blade, too few teeth.  A couple of questions:  How thick is the plywood?  How many teeth does your crosscut blade have?

   One thing you can do is browse a good manufacturer's catalog for their best ply blade(s) and see which one you have that comes closest to matching.  Two excellent blades for veneered plywood are the Freud TK806 (and "ultimate crosscut" blade) and the Freud F80.  These are both 80-tooth blades at 10".  The 806 teeth are flat-cut, the F80 teeth are a HiATB configuration.  Hook angles are different, but we'd better not go there -- too complicated, LOL.  [PS:  F80 and F810 are referring to the same thing]

   I have the TK806, and it does a beautiful job on what little ply work I've done with it.  If I'm remembering correctly, Mr. Lomax (an occasional visitor here at Knots) uses the F80 to cut fine veneered ply for his projects -- we had a long conversation at one of the WWing shows a couple years ago. 

   You've given me an idea for another thread.  Off to post.  Good luck.

   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" .... :>) 

   
   

   ---

   Edited 4/14/2004 12:08 pm ET by forestgirl

4. 
   ASK | Apr 14, 2004 08:44pm | #5

   Thanks for all your thoughts.

   Forestgirl, 3/4" and 1/2"

   I have an 80 tooth carbide tipped blade I haven't used yet which sounds like it might do the trick

   Thanks again

   ASK

5. 
   JsHerbel | Apr 15, 2004 07:52pm | #7

   Heavy masking tape on the bottom side of the plywood really helps to control tearout.

1. 
   ASK | Apr 15, 2004 09:04pm | #8

   JS,

   Thanks, good thought

   Never tried it before

   ASK

6. 
   Mackwood | Apr 16, 2004 12:14am | #9

   ASK,

   In addition to the blade recommended by "Mr. Freud", I've found that a strip of "Blue" tape (3M 2090) over the cut line helps a great deal.

   Regards,

   Mack

   "WISH IN ONE HAND, #### IN THE OTHER AND SEE WHICH FILLS UP FIRST"

1. 
   bfeng7 | Apr 16, 2004 06:09am | #10

   Charles has already given my favorite solution (Freud super laminate blade F80 or F810).  Before I had that blade, I use to use the two outside blades from my dado set. They were ground such that the pair was essentially an ATB.  It works in a pinch, or if you don't cut sheet goods often.

   John Feng

7. 
   RANGERP75R | Apr 18, 2004 03:00am | #11

   ASK

      I have the Freud laminate blade I use on the TS for smaller panels (under 4' x 4"). I cut larger panels down with a PC circular-60 tooth carbide and Tru-Grip and I'm with Mack on the Blue tape. I also score the cut with that set-up. Over-kill? Maybe.. But I don't get splinter.

   Regards...

   sarge..jt

   Proud member of the :  "I Rocked With ToolDoc Club" .... :>) 

1. 
   ASK | Apr 19, 2004 03:38pm | #12

   Sarge,

   Thanks, I never used the blue tape. Do you put it on top or bottom?

   If on the bottom, how do you compensate for the slight shift of the angle from the thickness of the tape?

   ASK

1. 
   RANGERP75R | Apr 19, 2004 04:00pm | #13

   ASK

      Running way behind, get back latter to-nite!

   sarge..jtProud member of the :  "I Rocked With ToolDoc Club" .... :>) 

2. 
   RANGERP75R | Apr 19, 2004 05:28pm | #14

   ASK

      Sorry, my teen-age son actually volunteered to wash two vehicles I didn't get to this week-end. Think I'll purchase a lotto ticket today with luck like that. ha.. ha...

      The blue tape is made by 3-M and is basically masking tape with an adhesive that won't leave adhesive when you pull it off. If there is a shift in angle caused by it, my tired old eye's can't detect it. :>)

      The way I use it (an I emphasize I) is I first set up my cut line. I use a Tru-Grip clamp with the edge facing the cut exactly 5" to the left of cut. I have a right side blade mount on my PC. That is the exact measure-ment from the inside of my circular blade keft tip to the outside edge of my PC circular saw base. If set up properly the cut will be on target as the base rides against the Tru-Grip rail as a rip fence.

      Once the set-up is made, I score the top line to a depth just below the surface veneer. Then I wrap the blue tape over the score line and all the way around the panel. And yep, that means the ends also. As I said, all the way around.

      Some might feel this is over-kill and vary their method. I use this cause it works for me and I have to this point never ruined or splintered an expensive panel. I use the same method on the TS after I have set up the rip fence to the exact width. Using an 80 tooth blade in combo with the TS, I sometimes drop the scoring process.

      It takes a little longer, but so does going to get another panel after you splinter one and dropping a wad of change to boot. Again, this is just my method. Others will probably post and you can choose your weapon as to what you feel is the most effective for you.

   Regards...

   sarge..jtProud member of the :  "I Rocked With ToolDoc Club" .... :>) 

1. 
   ASK | Apr 19, 2004 06:15pm | #15

   Sarge,

   I think I have as much of the blue tape as HD. I use it for a lot, but never as you suggested. Good idea. I'll try it.

   What's wrong with overkill anyway?

   Thanks again

   ASK