SawStop PCS Bevel Issue

[Shawn Pixley]

Yea that would be an option. I just don't now how well I can get the saw to compensate .02 degree off 90.... I'm hoping that adjusting the feed rate will minimize the deflection if it actually is the deflection.

I guess I really don't understand how you get those results. I use a Wixey angle box to set the blade angle. It measures in a tenth of a degree. When I set the stops I used this as well, but I recheck when I change the tilt or move it back. I also ensured that the throat plate / zero clearance is absolutely in plane with the top. I use a TK WWII most of the time. I never have had a problem with blade deflection. Unless you are just shaving the edge of a board at rip, the forces on the blade should be equivelant side to side unless you push / feed unevenly.

According to my simple calculations, 0.02 degrees over a 3/4" radius is well under 1/1000 of an inch. My clamps would pull this closed. Most joints will see a jointer plane after a cut (I use spring joints).

[Matthew Hills]

Bao Li,
When you said that certain areas on your rip are square and others have an error, is there any pattern to this?
(is one end good, and the other has an error, or is it a repetitive pattern?)

Is there any chance that the splitter is pulling the wood out of square?

Did you try crosscutting a short bord with the miter gauge and checking that cut for square?

Matt

[Andrew Pitonyak]

A few wild and crazy thoughts where I will summarize some of what I think I have read (in this thread), and some things that I have not....

1. You have some dry fine wood that cuts well
2. The blade is perpendicular to the table.
3. The front and back of the blade are the same distance from the miter track. More correctly, the blade is parallel to the track.
4. The splitter (or what ever that is called) is perpendicular to the table. Should be if the blade is.
5. The fence, when locked in place, is parallel to the track
6. The splitter is parallel to the blade. A straight edge might help checking this, I have never tested this.
7. You see these results with the SawStop supplied blade. I would test against this before trying another blade. if it is with the Supplied blade, then try another blade.
8. Have someone stand behind the saw when you push the board through. Does it look like the board stays against the fence as you push it through? I recently watched someone push a board through and it did not stay flush against the fence.
9. After your cut, parts of the cut are a perfect 90 and some are off by a small amount, remind me how small.

[Brian Tymchak]

having read the thread from top to bottom, I wonder if your feed rate is too fast, and / or inconsistent through the cut. I can envision a scenario where that might cause the inconsistent angle of cut with a thin kerf blade. Or maybe when you reposition your hands / push sticks as you push through the cut, the piece is walking a tiny bit off the fence.

[Bao Loi]

Having someone come in is the last resort. I'm still trying to see make sure its not technique that is causing the error.

Well... If the saw blade is 90* to the table & the fence is parallel to the blade, and the faces that are against the table & fence are jointed & flat, then the cut is going to be square. Maybe it's something to do with your technique? Might be helpful to get someone with some experience over to your shop to have a look. Sometimes a second set of eyes can be a big help.

[Bao Loi]

Thanks for the feedback! I have a Wixey angle reader as well and do use it for some measurements, but i always verify the electronic stuff with engineer square as a way to double check. Again, might be a perfectionist thing in me to this .02 degrees is not good enough. haha....

I guess I really don't understand how you get those results. I use a Wixey angle box to set the blade angle. It measures in a tenth of a degree. When I set the stops I used this as well, but I recheck when I change the tilt or move it back. I also ensured that the throat plate / zero clearance is absolutely in plane with the top. I use a TK WWII most of the time. I never have had a problem with blade deflection. Unless you are just shaving the edge of a board at rip, the forces on the blade should be equivelant side to side unless you push / feed unevenly.

According to my simple calculations, 0.02 degrees over a 3/4" radius is well under 1/1000 of an inch. My clamps would pull this closed. Most joints will see a jointer plane after a cut (I use spring joints).

[Bao Loi]

No direct pattern. The error is better after I purchased a jointer. The bevel is occurs more towards the ends of the board. Splitter is aligned from what I've seen. I did a crosscut and it had the same result.

Bao Li,
When you said that certain areas on your rip are square and others have an error, is there any pattern to this?
(is one end good, and the other has an error, or is it a repetitive pattern?)

Is there any chance that the splitter is pulling the wood out of square?

Did you try crosscutting a short bord with the miter gauge and checking that cut for square?

Matt

[Bao Loi]

Could be the technique, which I'm trying to work on just to make sure it's not me. So far I'm using a feather board and still get the same results. I bought a Gripper just to see if there is anything that will help there.

having read the thread from top to bottom, I wonder if your feed rate is too fast, and / or inconsistent through the cut. I can envision a scenario where that might cause the inconsistent angle of cut with a thin kerf blade. Or maybe when you reposition your hands / push sticks as you push through the cut, the piece is walking a tiny bit off the fence.

[Bao Loi]

Most of the items you pointed out are correct. I haven't had a second person help with the cut. The bevel at 90 degree according to my measurements is .02 degrees off 90 on a 3/4" thick board.

A few wild and crazy thoughts where I will summarize some of what I think I have read (in this thread), and some things that I have not....

1. You have some dry fine wood that cuts well
2. The blade is perpendicular to the table.
3. The front and back of the blade are the same distance from the miter track. More correctly, the blade is parallel to the track.
4. The splitter (or what ever that is called) is perpendicular to the table. Should be if the blade is.
5. The fence, when locked in place, is parallel to the track
6. The splitter is parallel to the blade. A straight edge might help checking this, I have never tested this.
7. You see these results with the SawStop supplied blade. I would test against this before trying another blade. if it is with the Supplied blade, then try another blade.
8. Have someone stand behind the saw when you push the board through. Does it look like the board stays against the fence as you push it through? I recently watched someone push a board through and it did not stay flush against the fence.
9. After your cut, parts of the cut are a perfect 90 and some are off by a small amount, remind me how small.

[Frank Pratt]

I'm wondering how you are measuring .02 degrees over 3/4". For 3/4" radius, 1 degree deviation would be about .0131", which would be visibly off. But .02 degrees would be less than 1/4 of 1 thousanth of an inch. Does anyone want to check my math on this?

If you breath on the edge of the board it will move more than that. You are chasing something that you will never, ever catch. even if you spend a million $$ on a table saw. Right about now, I can understand why the Sawstop guy won't call back, because what your after is just unreasonable.

[Jim Huelskoetter]

I will guess that your measurement error is larger than the actual error. You can measure the angle on 5 different pieces, preferably each slightly different angles. Try to forget the results and measure them again the next day. Then compare results. In a good experiment you would use more samples and multiple people, but this simple trial might show more variation than you would expect.

[mreza Salav]

I'm wondering how you are measuring .02 degrees over 3/4". For 3/4" radius, 1 degree deviation would be about .0131", which would be visibly off. But .02 degrees would be less than 1/4 of 1 thousanth of an inch. Does anyone want to check my math on this?

If you breath on the edge of the board it will move more than that. You are chasing something that you will never, ever catch. even if you spend a million $$ on a table saw. Right about now, I can understand why the Sawstop guy won't call back, because what your after is just unreasonable.

+1
I said it a few times, 0.2 degree is within the error range of the measuring device most likely (a digital angle finder). There doesn't seem anything wrong with the saw.
If everything is fine tuned as you say then: either you are splitting a hair and expecting accuracy that is not reasonable or it's your method of cutting that is not correct.
As suggested earlier, find an experienced woodworker to check your method or take your wood to someone else and see how they cut and what they get and measure that.

[Bao Loi]

Thanks for the feedback guys! I appreciate it!

+1
I said it a few times, 0.2 degree is within the error range of the measuring device most likely (a digital angle finder). There doesn't seem anything wrong with the saw.
If everything is fine tuned as you say then: either you are splitting a hair and expecting accuracy that is not reasonable or it's your method of cutting that is not correct.
As suggested earlier, find an experienced woodworker to check your method or take your wood to someone else and see how they cut and what they get and measure that.