Replies

1. 
   GHR | Sep 23, 2004 12:09am | #1

   Was that .003" in 10" or .003" in 1"? Lots of difference.

   Crank the blade up and down several times, tip the blade to 45 degrees and back several times. Check the alignment at all of those places.

   When I was a toolmaker, I used an angle plate with gage blocks to check my tools after any angle adjustment. I was happy with .001" in 6".

   I don't know any woodworker that checks his tools properly.

1. 
   oldschool | Sep 23, 2004 02:23am | #3

   Using a dial indicator, it was .003 off in a distance of 8 inches.

2. 
   sawdustmaker | Sep 26, 2004 03:41am | #14

   Thank you for speaking for (and to) all woodworkers out here. Maybe you can grace all of us with your personal instruction and give "how to" lesson for us idiots out here. We are not worthy. A$$.

3. 
   ELVY | Sep 27, 2004 07:15am | #16

   I like to use machinist squares rather than that expensive garbage with the "beautiful Rosewood handle".I recomend anyone who wants to learn fine woodworking to take a machinist course.

1. 
   Jeff | Sep 27, 2004 02:39pm | #17

   I don't know about you guys.

   I use a machinest's square and dial indicator to set everything square.

   Then I give my Beisemeyer fence a wack with the palm of my hand to square it up for cutting.

   Jeff

2. 
   JohnWW | Sep 23, 2004 12:12am | #2

   Three questions:

   1.  How did you measure the alignment?  Most of the methods I've seen described are prone to errors large enough to make measurements in thousandths of an inch suspect.

   2.  Misalignment is measured over a distance, how far apart on the top of the saw were the two points that were different by .003?  A misalignment of .003 over 10 inches isn't bad, over a distance of 4 inches it would be quite a bit worse.

   3.  What type of saw?  Most cabinet saws can be aligned and, with care, will stay in alignment to within a few thousandths, if that is what you need.  Contractor's saws, the new Ridgid excepted, are almost impossible to bring into that kind of alignment and won't hold the setting for long in any case.

   John W. 

1. 
   oldschool | Sep 23, 2004 02:33am | #4

   The saw is a Delta (Model 36-845) Left Tilt Unisaw.  I am extremely pleased with the saw.  The alignment was checked with a magnetic base dial indicator mounted on a runner that fit very snug in the miter gauge slot.  The .003 alignment was over a distance of 8 inches.

1. 
   JohnWW | Sep 23, 2004 03:46am | #5

   Presuming that you measured to the same spot ,front and rear, on the blade or test plate on the arbor, .003" out isn't likely to give you any trouble and is less than the typical runout on a blade and the play of most miter gauges.  Unless you can't live with anything less than nearly perfect, which you could possibly achieve on that saw, I wouldn't worry about it.  Have fun, make sawdust.

   John W.

1. 
   rod | Sep 23, 2004 05:30am | #6

   John,

      I'd like to ask you about this method to see if works well on a cabnet saw.  I raise the blade as high as possible. then I slide a good straight edge up to the blade not touching on teeth and measure the distance to the miter slot at the front and back of the saw with a dial caliper (the straight edge is 36 inches but the saw table is not so long).  I have been able to get the two distances to less than .005.  I use the same method on aligning the rip fence but instead use a One Way dial indicator for the measurments.  It seems to work for me, but I would like an opinion on the accuracy.

   Thanks, Rod

1. 
   BarryR | Sep 23, 2004 07:10am | #7

   Your method depends on the blade being perfectly flat, which it probably isn't.  You should come up with a method that checks the same tooth at the front and the rear.  That cancels out blade & arbor runout.  A simple jig that slides in the slot & has a brass wood screw you can adjust to barely touch a tooth can work well.

2. 
   JohnWW | Sep 23, 2004 04:17pm | #8

   Rod,

   The posting from Mangler clearly explains the reason why your technique can lead to an inaccurate measurement.  However, providing that your blade is reasonably true, your method would  get you close to having the blade and miter slot aligned.

   John W. 

3. 
   oldschool | Sep 23, 2004 09:21pm | #11

   My opinion, and its just that, is that a same tooth alignment measurement is the best way to go.  The measuring instrument that is used is a personal choice due to a person's comfort level of use.  I like the dial indicator because it is extremely sensitive and actually very easy to use.

   This thread started because I was in the process of building another (wider) cross cut sled to square up 23" wide panels.  I answered my own question on the .003 alignment.  This sled has produced square cuts that I didn't think were possible.  Now its on to cutting dovetails on the panels.  That's going to get my heart beat up. 

   John

3. 
   JohnWW | Sep 23, 2004 04:36pm | #9

   This is an excellent, even elegant, approach to checking the alignment.  I do a similar check all the time whenever I crosscut or rip, listening and watching how the cut edge passes the rear of the blade, if the rear teeth are taking off wood I know the alignment of the saw is going off.

   Dynamic tuning, as you call it, is the gold standard for setting up a machine.  No matter what the straightedges, squares, and dial indicators might say about the saw's alignment when the power is off, what really counts is the accuracy of real cuts in real wood, if the cut is right, the saw is right. 

   I always check a machine after technically tuning it up by making some test cuts.  I almost always find that some final fine tuning is needed to get the cuts truly square and straight.

   John W.

4. 
   JohnWW | Sep 23, 2004 05:55pm | #10

   Metod,

   You are welcome.

   John W.

5. 
   rod | Sep 24, 2004 03:47am | #12

   Metod, John, Mangler

      Thanks for your replies, I've printed them out and will try both the static and dynamic techniques that you suggest.

   Rod

6. 
   MichaelPB | Sep 25, 2004 11:34pm | #13

   Sure, you can settle for a clumsy method like actually seeing how the blade cuts but I prefer a far more accurate method.  Every quarter I hire a local aerospace firm to come out and use a very expensive laser measuring tool to set my saw to 1/10 millionth of an inch, only takes 2 days and costs about $5,000 but sure makes my craftsman table saw cut 2X4s like a dream!

   Next time I have to do it I think I will use your method instead though...

7. 
   mudman | Sep 27, 2004 07:13am | #15

   If you really want to get anal, check a thread I started about 4 weeks ago. I think I titeled it "Uni saw run out" I also started a thread about 3 months ago with a simular title but it dosen't have a solution. I agree that the most importaint test is the cut. I have spent time using a master plate and machinist square to set the blade on my miter saw, and then find that two 45 degree cuts didn't equal 90!

   Mike

   please excuse my spelling.