Replies

1. 
   forestgirl | Oct 14, 2009 09:32am | #1

   A local woodworker I know who worked primarily with thin sheets of veneered plywood used the Freud LU80 blade found on this page. 

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 
   
1. 
   boilerbay | Oct 14, 2009 05:42pm | #6

   FG,Maybe the boxman should give us his take. He does do a lot of kitchens.
   Dusty are you there?BB

2. 
   Dave45 | Oct 14, 2009 04:20pm | #2

   For plywood, it's all about tooth count. I get great results with my Oldham 60 tooth blades, and the Freud suggested by Forestgirl would be even better with 80 teeth.

1. 
   forestgirl | Oct 14, 2009 05:13pm | #3

   "all about tooth count" ... and configuration.  Charles-from-Freud, where are you? forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 

1. 
   Dave45 | Oct 14, 2009 05:31pm | #4

   True enough, FG. Configuration is also important. My point was that higher tooth counts give better cuts. The right configuration jut sweetens the pot. I can't imagine that a 40 tooth blade would ever make a really good cut in plywood - no matter how the teeth were ground. - lol

1. 
   forestgirl | Oct 14, 2009 11:12pm | #8

   Hope you saw Charles' reply above, very informative and his advice has, I'm sure, saved me money over the years when trying to pick just the right blade for the task.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 

2. 
   Tinkerer3 | Oct 15, 2009 05:39am | #10

   I know the question was about the blade to get.  Please don't forget that sharpness and alignment are probably the most important factors in getting a good cut.

2. 
   charlesm | Oct 14, 2009 06:41pm | #7

   To cut modern (thin veneer) plywood requires that the blade slice cleanly through the fibers and not pull out splinters on the exit side of the cut. Shearing the fibers is best accomplished with HiATB (over 30°) bevel angles on the tips. High tooth count will help but is not as critical as the grind (our P410 Premier Fusion does an excellent job with only 40T). A low or negative hook angle is also good to help with the exit side finish. For applications where you are cutting a LOT of sheets you can also substitute a triple chip grind with low or negative hook. The cut edge will be a little fuzzier but the blade should last longer between sharpenings. These same design factors apply to melamine and laminate. The LU80R010 that FG mentioned as well as the LU79R010 which is the thin kerf version are the best in the Freud line up.
   Charles M

   Freud America, Inc.

3. 
   Mackwood | Oct 14, 2009 05:36pm | #5

   I use the same blade that FG mentioned; it does an outstanding job.

   Regards,

   Mack

   "Close enough for government work=measured with a micrometer, marked with chalk and cut with an axe"

4. 
   davidbrum | Oct 15, 2009 02:28am | #9

   +3 on the LU80. Near flawless results. Just watch out for nails as the teeth are easy to damage.

   David B
5. 
   Knotscott | Oct 15, 2009 07:07am | #11

   The Hi-ATB grinds have the lowest tearout of any other grind, so something like LU80 Hi-ATB, or equivalents from Infinity (010-080), Forrest Duraline, Ridge Carbide, CMT, or Amana MB10800 will all give superb results that should be cleaner than what the WWII gives.  However, the one drawback of the Hi-ATB design is that it tends to wear more rapidly than other grinds.  If you plan on cutting hundreds of linear feet, it might be better to give up a little performance in favor of longevity with something like the LU85 with a standard ATB grind.  If it's more like thousands of linear feet, something with a triple chip grind (TCG) will wear even better...LU98R010. 

1. 
   charlesm | Oct 15, 2009 04:33pm | #12

   I agree with most of what Scott said. Two minor points: Freud HiATB blades have a special carbide formulation for wear resistance so the life is comparable to a standard ATB (although a nail is certainly the enemy of most carbide tips). And for a Triple Chip Grind blade I would recommend the LU97R010 (or the LU96R010 which is the thin kerf version) over the LU98R010 for better results on both faces of the plywood.
   Charles M

   Freud America, Inc.

1. 
   jonnieboy | Oct 16, 2009 06:53am | #16

   Charles,

   If I could,  I'd like to ask a related question here.

   I'm sure others here would know this answer as well. Feel free to chime in.

   I find the vee from the ATB blades objectionable. After looking at the Freud chart, I'm still confused as to which is a particularly good blade for plywood but which has a flat top grind. Or does a raker do the same thing as ftg? Well, whatever, I just don't want the vee.

   Edit: Or is the ATB the very reason the finish is so good, and to use an FTG would be to detract from that?

   Thanks.

   --jonnieboy 

    

    

   Edited 10/15/2009 11:56 pm ET by jonnieboy

1. 
   forestgirl | Oct 16, 2009 08:26am | #17

   Hi, jonnie.  Why do you find the Vee objectionable?  Perhaps I'm too sleepy to comprehend at this point, but that sounds like a dado objection (the proverbial "bat ears"), or am I missing something?forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 

1. 
   jonnieboy | Oct 16, 2009 08:56am | #18

   FG,

   I guess it is the "bat-ear" thing. I'm finding it difficult to get a seat that feels solid in that vee (actually it's more like a "W" though, isn't it.).  If the dado is shallow, the mating piece rocks around in it, despite the walls being tight fitting. There is certainly the question of skill in making the cuts, but why not go with an FTG and get as good a fit and as good a glue-joint possible?

   On a mortise and tenon the glue squeezes out of the mortise and you pretty much know that joint in there is coated, even though you can't see it. But with an ATB on a dado I can see that there are gaps where the glue can run right out the ends. Small yes, but gaps nonetheless. And with those gaps, how to clamp it well so it will overcome those gaps and be strong and consistent across the entire length of the dado? Does that makes sense? That's pretty much where I'm coming from. Perhaps I'm thinking about it all wrong. I've done that once or twice (today).

   Also, I've read here about aesthetic concerns of the "bat-ears," and I'm sure  I will come upon that as my skills grow. At this point I'm concerned about a fundamentally good structural joint.

   Didn't mean to go on and on. I'm not sure I'm saying what I mean to be saying.

   -jonnieboy

2. 
   forestgirl | Oct 16, 2009 09:05am | #19

   My understanding is that the ATB configuration of the dado blade is what enables the blade to cut clean dados.  I think it's a shearing action?  (Charles?)  I suspect if you used an FTG blade, say in some plywood, it wouldn't be all that pretty.

   Are you using a Freud set or another brand?  I have to look pretty close to see the bat-ears left when using the set I have.

   I'm sure Charles will come along and give us a thorough explanation.  The original post in this thread was in regard to regular cutting methinks, not dados or rabbets.

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 

   Edited 10/16/2009 2:06 am by forestgirl

2. 
   charlesm | Oct 16, 2009 02:48pm | #20

   jonnieboy,The bevel shaped teeth are the best at shearing the veneers with the least splintering. This is why our dado sets have them on the outside blades. A TCG blade will leave a secondary groove in the middle of the kerf from the trapezoidal teeth and will result in a little more splintering. To get a good finish and a totally flat bottom for a single kerf width (say 1/8" for example) you would need to use a trick like scoring the cut first and then follow with a flat grind blade. This could be done by using an ATB blade for a shallow pass and then switching to a flat grind blade of the same kerf to finish the depth. A similar method could be used for dado cuts by making a cut that is just shy of the desired depth and using a top bearing mortise router bit to clean out the bottom. A good quality combination grind blade or stacked dado set will produce a flat bottom with the aforementioned "bat ears". These V shaped cuts are going to be less than 0.008" deep and, although some complain about them, they are insignificant for most applications.
   Charles M

   Freud America, Inc.

1. 
   jonnieboy | Oct 16, 2009 06:57pm | #22

   Thanks much, Charles! That answers my questions completely.

   --jonnieboy

6. 
   bones | Oct 15, 2009 06:03pm | #13

   Prior to purchasing my Festool TS55, I used a PC 743 with a 7 1/4" Forrest WWII.  Worked fantastic! 

   I was married by a judge - I should have asked for a jury.
   George Burns

7. 
   wiskytango | Oct 15, 2009 09:24pm | #14

   Thanks all
   Sounds like ill give the LU80R010 a try.

1. 
   forestgirl | Oct 16, 2009 06:19am | #15

   Whisky, just a follow-up -- not everyone is in love with the red blades (sorry, Charles), so a reminder that the LU80M010 is an option.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 

8. 
   wotnow | Oct 16, 2009 04:21pm | #21

   Hi WT

   Just another option, (sorry Charles but we don't have much access to your product where I come from). I have had great success with A CMT blade with a 40 degree ATB grind and 5 degree hook,96 tooth. It gives as close to perfection I have ever seen and I use some pretty cranky timbers and ply. You can even get the blade as a teflon coated one if you are worried about resin and glue sticking to the blade. Also have used it successfully (no chipping) on melamine without a scoring blade.

   Bruce

9. 
   JerryPacMan | Oct 17, 2009 04:44pm | #23

   I have a Freud Fusion on my Hammer slider.  It is the blade I use when I want the smoothest cuts in both hardwoods and veneered plywood.

    

   Life is what happens to you when you're making other plans.

   When your ship comes in... make sure you are not at the airport.