Sawstop bevel axis adjustment question

[Aaron Rosenthal]

I’ve determined my (original) blade is within .005 front to rear on my PCS so no issues there.
Today I started using the saw for some 45 deg. mitre cuts and I found a frustrating issue.
I’m using an Incra 1000se miter gauge, which I checked is square to the blade @90 deg. Similarly, the reference edge is against the miter fence.
I set the saw at 45 deg. and checked with my Starret combination square’s “fence” but none of my cuts are square.
Naturally I’m working with the reference side against the fence.
I’m able to get the miter square by using my donkeys ear shooter, but the only way I can get the mitre cut square is to adjust the angle on the protractor by about 3/4 of a degree. Since I’m having to cut left and right miters, I’m obviously using up a lot of test pieces.
Is this normal, or am I in for a wash my mouth out session of adjusting?

[Mitch schiffer]

There was a thread on this not to long ago but I can't seem to find it. Maybe someone else remembers what to was titled.

[Patrick Varley]

Sounds like you have the blade aligned properly at 90deg, but have you checked that the blade is parallel along the tilt axis? You'd have to make sure that you're parallel to the miter slots after you've tilted to 45. If that's out, there's a somewhat tedious process to get it corrected in the manual ("Aligning the Blade to the Tilt Axis").

[Aaron Rosenthal]

I looked too and couldn’t find the thread. Blast it. Well, I guess it’s on with the knee pads (bursitis) and crawling inside the machine.

[Jerry Bruette]

Glenn Bradley had posted a very good explanation of the problem along with a solution. IIRC it involved shimming the table to correct the misalignment to the trunnions.

[Aaron Rosenthal]

Thanks to everyone. I’m stumped and so is sawstop.
I did every measurement by the book. Dial indicator, dead accurate spacer in the miter slot, checked the blade, parallel between the miter fence and the blade @90 deg, etc. No reading off zero front to back on the blade tilted to 45 no matter if I checked the same spot (felt pen dot) or at random around the blade.
Cutting 1x4 oak across the grain, or pine, the cut is about 3/4 of a degree out.
I’m not sure how to fix it, but I’ll look up Glenn’s post.
Thanks.

[glenn bradley]

Maybe it was this one? https://sawmillcreek.org/showthread....ons&highlight=

I want to clarify a couple of things. We are talking about bevel cuts where you tilt the blade, not pivot the miter gauge, yes? If I have that right let's dig further. Is this a cabinet saw or contractor saw? The link above will help if you have cabinet mounted trunnions. I don't know if the Saw Stop contractor has table mounted trunnions or not. Even if it does most contractor format saws make getting repeatable bevel cuts very rare. I guess we should clarify saw model and type of cut before I ramble on in the wrong direction ;-)

I will mention that this:

”No reading off zero front to back on the blade tilted to 45 no matter if I checked the same spot (felt pen dot) or at random around the blade.”

Is highly unusual. I generally see blade plate deviation of a thou or less. To see perfect zero at multiple locations is unknown to me. Are you using something that measures in thousandths? Actually you may just have a dial indicator that’s just that good and mine is just reading sloppy (?)

[Aaron Rosenthal]

Glenn and others:
Sawstop PCS 3 hp with the original blade in
I’m tilting the blade to 45 degrees, then using my Incra as the miter gauge.
Each time I make the cut, I make sure the reference edge is against the miter fence and the reference side is against the table. Since I’m making left and right mitres for the face, I switch sides and adjust the Incra so I don’t hit the blade.
The cuts are never straight across the miter.
I put my dial indicator up against an Oak offcut in the miter slot and it’s tight. Put the indicator base hard against the block and took the measurements.
I slid the block along the slot keeping the base in register.
It’s a cheapie dial indicator, but it’s never failed me before.

[Al Weber]

I have never been able cut square miters with the blade at 45 degrees until I made a sled to carry the piece. No matter how I try to prevent slipping along the miter gauge even if I clamp it, I get a little movement and a poor result. I finally Made a small sled to carry the piece and have not had further problems. I'm not sure if you are cutting a compound miter but you could still make a sled with an angled fence if necessary.

[glenn bradley]

Great. Thanks for the clarification Aaron. I use an Incra gauge and have since the V-27 cost about $35 . I bought a second one about 15 years ago or so to use on the router table. The point being I have used their gauges for some time. Despite being top notch tools there will generally be more deviation in a single slot stock guidance tool than a double slot tool. The amount of deviation will vary based on many things . . . material weight, length / leverage, cutter, surface friction, blah-blah-blah. You will see folks screw a second miter gauge to a sacrificial fence to add stability for precision cuts. You will see task specific sleds and all sorts of things to get the result one may be after.

For picture frames with parts up to 20" or so I do use my Incra gauge in the left hand blade slot. I angle the gauge versus tilting the blade and I also flip the stock versus sliding the fence position once I have it set up. I do use the notches in the gauge head to set the 45 degree angle. I use a shop made 45 degree stop block to batch out parts.

5X5 Frame (9).jpg . 5X5 Frame (11).jpg

I know it doesn't help to see a non-problematic result but, using this method gets me pretty air tight miters right off the saw.

5X5 Frame (16).jpg

You might give it a try angling the gauge head instead of tilting the blade.

I recently finished a 24" x 36" shadow box with sides about 5" deep. This required beveling the blade as you are doing. I did use a two-runner sled for these cuts. The stock looks a bit odd as it is a blank of plywood with a thick cherry veneer on each face. Be that as it may, you can see the sled.

Shadow-Box (1).jpg

I use the same setup to cut slots for splines on this particular item.

Shadow-Box (2).jpg

Again, not much help to show a setup that works when you are troubleshooting a problem but you may see something that makes you consider something you may not have otherwise.

Shadow-Box (3).jpg

You may notice that I control the stock with hold downs. I cannot stress how much impact very little movement during a miter cut can have on the result. One of the first giant steps in my progress toward getting good miter joints was lining my miter gauge fence with sandpaper. I thought I was holding the stock really well. The difference between cut results with and without the abrasive in place was very revealing.

For longer miter cuts like the shadow box shown above or for mitered boxes I always use a sled with hold downs.

Bevy of Boxes (1).jpg

Even though your stock has been prepared dead flat, subtle motion during the cut operation will hand you miters that don't fit well. I hope some of this helps with your issue.

P.s. I'm sure your dial indicator is fine for tablesaw setup. Mine is a $10 Harbor Freight and I have used it for many years with good success. You are really measuring a difference between one point and another. An exact dimension isn't as important as a repeatable first number to compare to a repeatable second number in many machine setups.

[Eric Schmid]

You’ve mentioned you’re using the original blade. What about trying a new or freshly sharpened quality blade before adjusting the machine. It doesn’t sound like you’re getting any indication the saw is out of alignment. This seems to point to work holding and/or the condition of the blade. Or possibly the wrong blade for the task.

[Greg Funk]

The cuts are never straight across the miter.

Do you mean the cut is irregular or not square. If it's irregular it sounds like the piece is moving across the fence of the miter gauge. Do you have a crosscut sled you could try? Or perhaps glue some sandpaper to the fence to limit movement?

[Aaron Rosenthal]

Greg, the cuts are not square. I’m looking to make a sled to see if that helps.
Eric, one of the things I asked the tech at SawStop was, after describing all the steps, could it be the thin blade deflecting as I’m going through the Oak. It’s one of the changes I’m making this week, putting in a full kerf blade which is clean and sharp although 10 or so years old.
Let’s see what tomorrow brings.