Riving Knife Alignment

[Ryan Dyer]

Hey guys,

I recently bought a Grizzly G1023RLW. I spent 4 hours trying to get the riving knife aligned according to the directions. I finally realized that i never could because the blade was to far to the left and there wasn't enough adjustment to even push it back that far. You can see in the pic below. Thats with the block all the way in. The riving knife is flipped backwards for the picture so you can see the blade.

2011-11-15_21-38-21_146.jpg





So i called Grizzly and mailed them the mounting block where they shaved off 1/16". Now i should be able to align it since it will go well past the center of the blade, but another 2 hours and i still cant get it right. Anyone have some tips/tricks to get this thing aligned. It has 4 bolts, each on a corner of the block that you screw in/out. It seems i move one and it pushes something else out of alignment. I got it "good enough" to use, but it bothers me its not more centered in the blade.

[Prashun Patel]

Perhaps the arbor flange needs to be adjusted.

[Floyd Mah]

I know that this an unsatisfactory solution, but you could shim the blade to line up with the riving knife if you need an interim solution. They sell shims that are used with dado blades to micro adjust the width of the cuts.

[glenn bradley]

It sounds like shimming is not the issue. He can now adjust the RK within the range required (following a really weird fix by Grizzly, I'm still scratching my head over that solution) but is having trouble reaching the combination of planes he is after. Glancing at the manual it appears to be a four-point control mechanism similar to the parallelogram bed adjustments on my jointer. I appraoch these types of adjustment one plane at a time. I would (and I'm talking through my hat here):

- zero the front two screws
- use the rear two screws to reach the approximate position left to right BUT perfectly up and down (90* to the table)
- use the front two screws to bring the front edge into line with the now perpendicular rear edge

At this point you are perfectly perpendicular at 90* to the table and very close to the left-to-right position you are after. Place your straight edge as instructed in the manual and make the minor adjustment to position the RK in the path of the blade kerf. Now set tour height. This sounds easy from my armchair-quarterback/backseat driver position. Hopefully it is somewhat useful in the real world.

[Kevin Presutti]

Just looking at your photo could it be that the RK mounting block is not square to the trunion? I am merely suggesting this as it looks like it is angling away a degree or two from the trunion, but it may be just the photo. I am also assuming the photo is prior to them remachining the the flat that the RK sets up against. Maybe the thing isn't machined square. Remember there are 2 fixed items in this eqaution, the arbor and the blade. Assuming the blade is perpendicular to the arbor in all axises x,y and z. Based on the min/max for both the blade and RK the block surface that the RK rests against would have to be .012" to the left (looking from the working end of the saw) from where the blade rests on the arbor if your RK were machined to the max. thickness that dimension would then be .016. It would appear that these would almost have to be matched (RK and the mounting block) given the very close tolerances of the blade thicknesses allowed in relation to the thicknesses that the RK given in the manual. So with all that, the surface on the trunion that the block mounts to has to be paralell to the arbor (x axis) and the surface the RK butts up against should be perpendicular to the arbor (y and z axis), any deviation there will compound problems when trying to line up the RK with such tight tolerances and with said you are probably all confused now. I just worked it backwards, .012/.016 leaves you .004 to move the RK which is really not much at all. The instructions in the manual are somewhat hinky, but using the numbers they give you that is my conclusion. If I am missing something here someone please correct me. The manual from grizzly has a typo stating the min/max RK thickness is 0.98" - .102" which I corrected to .098 - .102 and worked from there. I'm sure by now I have everyone confused but it seems as though it's just plane geometry. Again please feel free to correct me but I am just using grizzly's numbers.

[keith micinski]

If it makes you feel any better I spent hours getting my Riving knife on my 1023 adjusted and to be honest with you it could still use a little tweaking but it is close enough that I gave up and left it. The main thing I did was zero all four screws out and then I equally tuned them out and counted the turns. I was able to get it close enough that once I started making minor adjustments to true it up,things didn't go haywire on me. Also after every adjustment make sure you tighten the two screws down that lock it in. I got lazy for a while and was just doing adjustments with out locking it down and it threw things completely off.

[Jim Andrew]

Really surprising for you to have this problem. The Grizzly tools I have purchased have been adjusted correctly, the problems coming from my own not understanding how everything works. Had a problem with my sander, read the old posts on SMC, found a post from Shiraz which explained what I was doing wrong.

[Rod Sheridan]

As others have said it"s either a faulty saw or you're not adjusting something properly.

Since Grizzly don't offer field service you're at the exchange or pay a machinery tech to have a look at it for you..........Rod.

[Doug Morgan]

From the picture you have and the instruction manual something isn't the same. It looks like there should be a couple of lips on the block to hold the riving knife. On your picture, I see one side with them and the other without. Are they there? I may not be able to see them. If they cut off the "tabs" and counted that as your 1/16" that would do you no good. I would think they would have to take it from the rear of the device. Make sure that there is nothing between the mounting block and the saw. I downloaded your manual and read it but I cant see anything to hinder your mounting block. The issue has to be between the mounting block and the saw if I understand everything I'm reading. I like Keith Micinski's idea on the adjustment. Screw out the adjusting screws all the way and begin with a fresh start.
griz manual.jpg

[Kevin Presutti]

Doug,
The RK is shouldered per your drawing, I believe that is why you don't see the raised edges on the mounting block. I think something isn't square with the world there, the numbers Grizzly gives you when you do the math doesn't leave much wiggle room IMHO

[Jim O'Dell]

I don't know about the 1023R series, but my 691 was a little off, and took about 2 hours learning curve time to understand what I was doing when I turned any of the adjusters for the RK. Think of the 4 set screws in 2 different planes. You can canter the RK left to right by moving the front 2 and rear 2 screws in pairs. Or you can tilt the RK in and out by using the top 2 and the bottom 2 screws in pairs. Does that make sense? But it looks like from your picture that you can't get the RK far enough over to center the blade. I see in the exploded view what looks like the 4 set screws, but I don't see what they would ride on to move the aligning plate, either in the picture or in the exploded view. Maybe you have it already as far against it as you can. But yes, you move one screw, and it changes at least one other plane, if not 2...makes for a lot of aggravation until that light bulb goes off. But again, unless I'm not seeing something, that is not your immediate problem.
Sorry I can't offer any wisdom on this particular saw. When I helped Adrian set his 1023R saw up, I think I ran out of time before we got to the RK alignment part. But everything else on his saw was pretty much dead on out of the box. Hopefully someone with some real world experience with this saw will chime in. Jim.

[Adrian Anguiano]

Did u get the riving knife fixed? Mine was thankfully perfect and didnt need adjusting.

Did you check to see if your riving knife was perfectly flat with a straight edge and a light? The instructions litterally say to bend the riving knife if its not.

[Ryan Dyer]

Yes, i did get it good enough...it was perfectly flat when sat on the cast iron surface of the table saw.

What i did, was layer 3 pieces of 3/4" MDF and screw them together. Then cut into the block of MDF about half way, and used business cards shimmed on each side of the riving knife to hold it in place. Then VERY gently adjust the screws until i could just feel touch. Tightened it down. Its not perfect, but its good enough...

[Robert Moffa]

My question is how in heck did you get to those adjustment screws without taking the table off the machine??? Fortunately, mine is correctly aligned, but I was looking at the process the other day just in case I needed to work on it in the future. I can't see how it is possible to access those screws from the blade opening.

[Ryan Dyer]

My question is how in heck did you get to those adjustment screws without taking the table off the machine??? Fortunately, mine is correctly aligned, but I was looking at the process the other day just in case I needed to work on it in the future. I can't see how it is possible to access those screws from the blade opening.

Through the right side access door. Yea, it was a lot of fun getting down on the floor so i could see what i was doing through that door, then having to get back up every time to check it.