Replies

1. 
   mike_b | Aug 06, 2007 02:37am | #1

   <<as soon as I turned on the saw it started rattling around>>

   For whatever reason, it sounds as if the blades, chippers and nut weren't properly tightened (assuming you're using a stacked set). You'll want to make sure that the carbide cutters on the blades and chippers are not touching each other. I find it helpful to distribute the chippers as evenly as possible around the arbor. I'm not sure why you would have a tough time removing the blades and chippers. Perhaps they were just over tightened.

   Mike

1. 
   Woodman880 | Aug 06, 2007 03:17am | #2

   I’ve been doing some internet reading and I think the problem comes from my not installing the blades and chippers properly. These blades are somewhat new to me and they did not come with instructions. Part of the problem comes from trying to adjust the blades with a large hand in a small slot. It would be nice if I did not have to put together a jigsaw puzzle every time I put the dado blades in place. Are you aware of any types of dado blades that would be easier for a large hand to install? I came across a web page of one man who simply put regular saw blades together for his dado cuts.Edited 8/5/2007 8:18 pm ET by Woodman880

   Edited 8/5/2007 8:18 pm ET by Woodman880

1. 
   hammer1 | Aug 06, 2007 04:37pm | #7

   Hi Woodman, There aren't many of us that can get our paws in the saw throat. Some saws are tighter than others. The first thing you should do is unplug the saw, don't rely on the switch! Raise the arbor. With many sets, there is an outside cutter and an inside one. These can often be identified by the paint or markings on the blades or the tooth configuration. When you place each cutter, push them up tight to the arbor flange and keep them tight to it as you add cutters. Make sure that the chippers are arranged so they balance. Only two chippers, have them in a cross, three, in thirds, etc. None of the carbide teeth should touch each other in the stack. When using shims, again, push them up tight against the cutters. In many cases, you can place more than one shim between chippers as long as the adjacent carbide teeth overlap each other. The thin shims can get hung up in the threads of the arbor. If your shims are galled on the hole, flatten them out. Push everything tight to the flange before placing the nut. You should be able to tell that all is fitting tight. Don't over tighten the nut, just lightly firm.Obviously, you need a throat plate with a slot that is wide enough for the width and height of the dadoes. Most of the time, I use dadoes for rabbets or end dadoes, where the cut will be on the edge of the work. Attach a wooden sacrificial fence to your saw fence and raise the cutters so the edge of them is buried in the sacrificial fence. When you are done, remove the sacrificial fence so ordinary work does not get hung up in the cutout. When crosscutting dadoes, it's best if you use the miter bar or a sled. You need to add a wood fence to the miter bar and it's a good idea to glue some sandpaper to it so your work can't slip. Since the dadoes are cutting a wide groove, if your work moves, it can bind and kickback. I prefer to cut crossgrain dadoes in wide work pieces with a router. There are ways to make multiple passes with a smaller bit to make a dado that fits the work. This is much safer than trying to crosscut a large panel with dado blades. Like many woodworking processes, you need to match the work to the method. Anytime you are using the saw fence, the work piece has to be straight and you need to maintain contact with the fence all the way through the cut. You should also have an outfeed table to support your work as it leaves the saw. I wouldn't use a table saw without a straight edge on my work and an outfeed table. Do not try to stack up ordinary blades. The teeth will hit each other and the circumference will not be the same. Be very careful where you get advice, there are some nuts out there and many who don't know what they are talking about. Get some good books. Internet forums are good for entertainment, not for sound advice.Beat it to fit / Paint it to match

1. 
   Woodman880 | Aug 06, 2007 09:29pm | #10

   Thank you for taking the time to pass along the tips.

2. 
   AlanWS | Aug 06, 2007 03:37am | #3

   The intermittent difficulties in installing and removing the dado stack, and the incomplete tightening could be due to shims that have slipped down into the arbor threads. Tightening can pinch and shear a bit of the edge. If you look at the central holes of your shims and they look chewed, this might be your problem. One solution is to be vigilant and make sure each shim slides on completely.

   A more complete solution to your problem might be the Freud dial a width dado set. It's a dado stack that you handle as one object, as you wanted, and where you don't need shims to space the blades and chippers for the cut. My understanding is that many saws have arbors that limit the dado width for this set, and you need to evaluate your saw and needs. You'll need to ask someone else for any more detail than that, as I haven't used it.

   If you wanted only 1/4" and/or 3/8" cuts, the Freud box joint cutter works beautifully. That blade I can vouch for. I don't know of a 1/2" version.

1. 
   Woodman880 | Aug 06, 2007 04:15am | #4

   You may be right about the shims. I've noticed the center hole is a bit chewed up on them. I'm going to check out the dado you talked about. Thanks

2. 
   Woodman880 | Aug 06, 2007 04:27am | #5

   Again, I appreciate the tip. I checked out the Freud dial width dado set and it appears to be a unit that you assemble to width before you install it. It’s a little pricey so I think I’ll put it on my Christmas wish list.

3. 
   ring | Aug 06, 2007 06:45am | #6

   You can use shaper blades on the tablesaw if the arbor will allow it.  My shaper has a 30mm shaft which is identical to my tablesaw, so it's no problem.  Shaper cutters come in a great range of sizes.  If you're using the same dado often, look into it.

   David Ring

   http://www.touchwood.co.il/?id=1&lang=e

4. 
   Dave45 | Aug 06, 2007 04:48pm | #8

   I've seen a couple of things cause a stacked dado cutter "rattle around" like that.

   • The teeth of the blades and chippers are in contact and that "cocks" them at a slight angle.  When you're making up your stack, make sure that the teeth are in the gullet of the adjoining chipper or blade.
   • Your shims are slipping into the arbor threads which can also "cock" the chipper or blade.  This problem gave me fits until I got these magnetic shims.  They're sort of like refrigerator magnets and the printed side sticks to the blade or chipper so it doesn't try to drop into the arbor threads.  As far as I'm concerned, they're the greatest thing since sliced bread.

   
1. 
   Woodman880 | Aug 06, 2007 09:28pm | #9

   Your analysis of my dado problem is exactly what has been happening to me. Do you assemble your dado stack before you install it on the saw, or does your assembly take place piece by piece on the saw?

1. 
   Dave45 | Aug 07, 2007 02:44am | #14

   I make the stack up one piece at a time.  I've long since figured out which shims I'll need to get close to my desired width so they go in as I build the stack.  Since I started using the magnetic shims a couple of years ago, I can make up the stack in a couple of minutes without worrying about shims slipping into the arbor threads.

   However, I still make a few sample cuts in scrap to "tweak" the shimming as necessary to get snug dado's.

2. 
   Woodman880 | Aug 06, 2007 09:33pm | #11

   One other thing, is it necessary to use shims with the dado blades or are they just included for fine type adjustments?

1. 
   MikeHennessy | Aug 06, 2007 10:15pm | #12

   "is it necessary to use shims with the dado blades or are they just included for fine type adjustments?"

   The latter. Also, I build my dado sets on the arbor -- it would be way to tough to get it stacked and then put it on the saw all at once. I also keep a chart handy where I record what combinations of blades/shims make up standard measurements and ply measurements, since figuring it out once is tough enough.

   Mike HennessyPittsburgh, PA

2. 
   Dave45 | Aug 07, 2007 02:39am | #13

   Since plywood is typically 1/32" less than the nominal thickness, you can't get a tight dado with just the blades and chippers.  You need to make up your dado stack with the right number of chippers to make a slightly undersized dado, then add one (or more) shims to get the width you need.

   To add to the fun, plywood isn't always consistent in it's thickness.  The 3/4" ply I've used in the last few cabinets I've made was actually 11/16".

   I've found it necessary to make sample cuts in scrap - changing the shims as necessary to get the right dado width for the plywood I'm using.

5. 
   troys | Aug 07, 2007 07:44am | #15

   In the past I have seen 1/2 wide blades to make slots or dado's I think the company that made them is "Freeborn" It has been a long time since I have read about them though. Good luck.

   Troy