# Table saw accuracy



## Dave Mills (Dec 4, 2019)

I'm making sort of an art piece for my father, and really trying to dial in the accuracy of these pieces. Thus far, it's 90% table saw work, and by the time I drew it up (to scale) with 1mm spacing between the keys, width of dado cutouts of numbers like 6.5mm, I realize I may be at the limit of my (current) accuracy levels. I'm making test cuts, moving the fence a hair, measuring the result with a caliper, etc. Once I get it as close as I can, I make all the cuts of that size. It's going ok, but boy if I screw up one of these keys, getting the saw set to the same spot later is going to be a project. And it seems like there may be a better way.

So I was wondering if folks have any tips for this kind of thing. I see there's a product from Wixey that allows you to dial in a measurement and set the fence very accurately... any feedback on those? If I wrote down a measurement, could I come back a week later, just set the fence at 6,5mm and expect it to be "right"? Any other thoughts for cutting to very exacting tolerances?


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## Tom-G (Nov 11, 2012)

Dave,

When I need to make another identical cut, I use one of the good pieces that I need to match. Place it between the fence and blade and adjustment/lock the fence so that when I move the blade by hand (saw unplugged) the carbide tooth just clears the sample. I then do a test cut, check the test piece against the original, and most of the time it’s perfect. Otherwise a slight tap with my hand on the fence and re-lock usually does it. You will need to get the “feel” for how this way of aligning works on your saw, but once you figure it out it’s repeatable. 

Tom


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## GeorgeC (Jul 30, 2008)

That is exactly what I do. Much simpler and more accurate that the measuring tool.


George


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## Dave Mills (Dec 4, 2019)

But how do you set up the first one, when the size dictates 6.5mm wide, by 8mm tall or so. Trial and error and calipers, or some other way?


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## B Coll (Nov 2, 2019)

Whenever accuracy and repeatability are paramount I make fixtures to use. I try not to ever move the fence, usually using some sort of sled that will run in the miter slot. Sometimes it may take you longer to design and make the fixture than to do the cuts, but think it through. It will come to you. I find I can never have complete accuracy or repeatability if I am moving parts, such as a fence. Another option, where appropriate, is to make templates and use a pattern bit on a router table.


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## Terry Q (Jul 28, 2016)

A Incra LS Positioning fence would allow you do what you want. The American version locks down every 1/32 in, the metric 1mm, but if you want to do a cut between you can dial that into hundredths. It is repeatable and you can go back at any time in the future and dial in the exact measurement as previously.


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## Nick2727 (Jun 14, 2020)

This cheap incra jig attaches to your own fence. To give 1/32nd accuracy on your fence, problem is once you set up you only have 8" of working room. Good for drawers though.
https://www.ebay.com/itm/Incra-Jig-...714536?hash=item1a9ea441a8:g:QPwAAOSwYYBfI2Hk

Edit: I realized after the fact your measurements listed were in mm. Not much good for a 1/32nd jig.


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## brucet999 (Feb 23, 2019)

That Incra LS positioning fence seems to be for a router table. I don't understand how that could be used on a table saw. 

Am I missing something?


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## brucet999 (Feb 23, 2019)

A simple jig for re-positioning the fence might be a stick of hardwood cut to fit the miter slot. Drill a countersunk hole on the under side and run a machine screw through it. Then all you need is a piece of hardwood or baltic birch with a slot to fit over the screw, and a washer and wing nut.

Now, once your fence is set properly for your original cuts, position the jig with the slotted piece pressed against the back side of the fence and tighten the wing nut (or if you want to be fancy, a threaded knob). Label your jig and set aside for next time.


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## epicfail48 (Mar 27, 2014)

Ive got the Wixey gauge on my saw, had it for a few years now. Gotta say, its really a game-changer for accuracy, i highly recommend it. You do have to calibrate it every so often, but it gives bang-on results. The biggest advantage is exactly what youre trying to fix; if you move the fence, you can get it back to the exact same spot with no fuss


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## JohnGi (May 9, 2019)

This is the old trick from the rule die trade when you need to match the width of a ripping exactly: take the piece, place it against the fence, set the fence a bit wide, rip a scrap piece using the edge of the original ripping as a guide, then set the ripped scrap against the fence and make your new ripping using the edge of the scrap as a guide. It works to match the length of an existing piece on a radial arm saw as well. With small pieces, you may have to think a bit about push sticks and hold downs to do this safely.


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## Terry Q (Jul 28, 2016)

brucet999 said:


> That Incra LS positioning fence seems to be for a router table. I don't understand how that could be used on a table saw.
> 
> Am I missing something?



Yes you are, they make one for tablesaw as well.


https://incra.com/table_saw_fences-tsls_fences.html


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## woodnthings (Jan 24, 2009)

*Good tip ?*



JohnGi said:


> This is the old trick from the rule die trade when you need to match the width of a ripping exactly: take the piece, place it against the fence, set the fence a bit wide, rip a scrap piece using the edge of the original ripping as a guide, then set the ripped scrap against the fence and make your new ripping using the edge of the scrap as a guide. It works to match the length of an existing piece on a radial arm saw as well. With small pieces, you may have to think a bit about push sticks and hold downs to do this safely.



I am sincerely trying to understand this.:nerd2:
This is the old trick from the rule die trade when you need to match the *width* of a ripping exactly:

take the (original?) piece, place it against the fence, set the fence a bit wide, rip a scrap piece

using the edge of the original ripping as a guide, .....? (guide?)

then set the ripped scrap (slightly too wide?) against the fence and make your new ripping 

using the edge of the scrap as a guide.....? (guide?)


It works to match the *length* (length? are we now crosscutting rather than ripping?) of an existing piece on a radial arm saw as well. With small pieces, you may have to think a bit about push sticks and hold downs to do this safely.


I'm sorry I just can't grasp this tip. :sad2:


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## Bernie_72 (Aug 9, 2020)

brucet999 said:


> That Incra LS positioning fence seems to be for a router table. I don't understand how that could be used on a table saw.
> 
> Am I missing something?


Incra has units that are just for a router table and they have units that are just for table saws. If you have a router table extension on your table saw you can get their joinery system that has both options.

I put this on a few months ago and after getting it dialed in I cut a 5" board, 4" board, 3" board and a 2" board. When I put the boards together the combined measurement of all 4 pieces was off by just 1.5 thousands of an inch. It is a spendy but incredibly accurate way to make repeatable cuts.

The first picture includes the Incra wonder fence that I use for routing work. The second picture is with just the fence I use when making cuts with my table saw.


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## Tool Agnostic (Aug 13, 2017)

I subscribed to this thread. I hope to learn good techniques for repeatable, resettable rip cuts. I don't have issues with crosscuts on the table saw if I use a sled. 

Based on previous experience, I never trusted my table saw rip fence rail scale, preferring "cut to fit" and "adjust fence with blade teeth to match" techniques with test cuts in scrap. That was true for the jobsite saw I had in recent years, and other saws I have used in the past, especially the radial arm saws. Now I use a SawStop cabinet table saw.

I mentioned my reluctance to trust the rip fence ruler to friends who own SawStop cabinet saws. They were surprised, and told me that they relied on their SawStop rip fence rulers for highly accurate, repeatable cuts. They set the width they want and cut without testing on scrap or any other preparation. 

After testing with calipers, I learned that my friends are mostly right. Using that approach, I get resettable repeatability between 1/64 and 1/128 inch (around 1/4 mm). That's within the limits of wood and my cutting skills anyway. Accuracy depends on alignment and calibration, and you have to recalibrate any time you change the blade or make an alignment change. (Note: The fence can move as you clamp it. You must check the measurement _after_ you clamp the fence. You can reduce movement somewhat by pulling the fence towards you as you position it before clamping.)

At some point the question becomes moot, because wood itself is unpredictable and there is still room for for me to improve my rip cutting skills. 

I am watching this thread with interest.


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## Dave Mills (Dec 4, 2019)

I have been doing the same, using just the scale on my SawStop Biesmeyer-style fence, for any normal cut. If I need something 6-5/16" wide, that's fine I just set the fence and cut. That's after a) setting the scale up back when I got the saw and b) making sure I only use blades with 1/8" kerf. The factory supplied combo blade is not 1/8", so I chose to trash it in favor of simplicity.

For these piano keys though, the measurements I was trying to reproduce were to 0.5mm both for rip and crosscuts, and just a bit more granular than I could manage on the crosscuts. I'm sure the Incra fence would do the trick.

What I finally did on this project by the way was the "make a test and adjust from there" method.


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## woodnthings (Jan 24, 2009)

*Setting the fence indicator is easy ....*

For "no measure cuts" using the hairline indicator and measurement tape on the fence rail, there's an easy way to precisely adjust the hairline indicator.


(1) Set the fence over to any width, say 18" plus or minus. Make a rip cut using the fence. Measure the result as accurately as possible. Then adjust your hairline indicate to that dimension. 



(2) Set the fence to a different dimension using the hairline indicator, but less than before and make a second rip cut. Measure the result and see if it's the same as your setting. If not readjust slightly and repeat the process.


This method requires you always use the same kerf blade. :|
For repeatable cuts, just place a strong magnet on the right side of the fence rail, bumping it to your last fence setting before moving it.
Now you can move the fence to the left in any amount, but not any further to the right than the last rip. For greater rips to the right, just reverse the magnet to the left side.


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## Dave Mills (Dec 4, 2019)

That's a nifty trick with the magnet!


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## brucet999 (Feb 23, 2019)

woodnthings said:


> (1For greater rips to the right, just reverse the magnet to the left side.


Wouldn't that magnet placed to the left of the fence get in the way of the wood you want to rip to a greater measurement to the right?


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## woodnthings (Jan 24, 2009)

*You need to choose ...*



brucet999 said:


> Wouldn't that magnet placed to the left of the fence get in the way of the wood you want to rip to a greater measurement to the right?



The magnet I use is attached to the rectangular steel rail (Bisemeyer) the fence rides on. It can be placed as a stop on either side of the fence head, you just need to figure out ahead of time what your work sequence will be. Hopefully, your widest rips will come first, then the narrow ones. It's only a quick and dirty "short cut" and it's always good to measure to be certain. :wink:


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## brucet999 (Feb 23, 2019)

That Incra LS is an impressive tool, but with 72" rails, too wide for my little Delta hybrid saw that has to fit in a 64" wide space along the wall of my shop/garage while not in use. The right side has a shop-made router table/extension. 

Does anyone know of another good alternative to my Delta knock-off Beesemeier-style T-fence, that could deliver accuracy approaching the Incra system?


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## Terry Q (Jul 28, 2016)

The Incra LS Positioning fence is unlike any other fence on the market.

Once you understand how to use an Incra fence you’ll change the way you use table saw fences. For instance, if you needed some thin strips, say 1/8 inch or less.

There are a bunch of jigs and devices to help push a board past the blade with your typical fence, but with an LS Positioning fence it’s a completely different procedure. You grab a nice wide board, set your fence to the nearest 1/32 inch width of your board and rip your board parallel. Then subtract the kerf of your blade (full kerf 1/8” blades makes for easier calculations) and the desired thickness of strip, as thin as 1/32, and move the fence. Shove the nice wide board past the blade and your strip comes off the outside. You keep moving the fence. Impossible with standard fence, but with Incra fence it is accurate and easy to do. 

Before giving up on the idea you should write to Incra technical support asking for advice for fitting a fence to your saw. It’s probably something they deal with on a regular basis.


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## brucet999 (Feb 23, 2019)

"Before giving up on the idea you should write to Incra technical support asking for advice for fitting a fence to your saw. It’s probably something they deal with on a regular basis."

I've done that already, but as I think about it further, I realize that at 72" long rails, Incra gives only 32" of cut to the right of blade. Cutting off 10" of the rails would likely leave me with only 22" maximum cut. My old Delta T-fence gives me 31 1/2" cut and I don't have to remove it in order to run a router bit with a bearing on my right-side router table/extension.

I like the idea of precision, but spending $500 for 30% _less_ cut capacity doesn't much appeal to me.


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## kwoodhands (May 1, 2020)

Install dado blades . Clamp a short fence to your fence for setting distance only. Cut your keys to length and clamp a key to the miter gauge fence. Bring the blades UP to height. This is important as lowering dado blades often results in blade drop. The short fence is set to the shoulder distance and then the key is clamped. You will pass the short fence for the actual sawing. This eliminates the key binding between the fence and the blades.
Make a pass, turn key over and repeat. You will have a shoulder cut on each side of the key. Set one key aside and repeat for the remaining keys.
Now make a jig . Plywood or MDF base about 8"x8" . Add a strip 1/32 or so thicker than the keys and about 4" wide.
This strip is fastened on the MDF . Notch the strip for the width of the saw cut and also the length. The length is not real critical because you made the shoulder cuts first. Add a top to the strip to keep the key trapped in the notch and your fingers away from the blade. If you have compressed air, blow the off cut off the table.
Make the cut on each piece, just one side for now. When the keys are done on one side then add a spacer to the jig the width of the cut . This prevents the key from tilting 
to the right side of the jig. The keys are then cut. 
A Freud glue line blade will make a clean cut . If the dado blades do not give you a smooth cut, make the pass a bit heavy and clean up with a chisel or sanding.
There is another way without dado blades and without the jig described. You would need a tenon jig . Because the cut strip will be trapped between the blade and the fence I won't recommend it for most woodworkers.
mike


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## woodnthings (Jan 24, 2009)

*Table saw accuracy = fence accuracy!*



brucet999 said:


> That Incra LS is an impressive tool, but with 72" rails, too wide for my little Delta hybrid saw that has to fit in a 64" wide space along the wall of my shop/garage while not in use. The right side has a shop-made router table/extension.
> 
> *Does anyone know of another good alternative to my Delta knock-off Beesemeier-style T-fence, that could deliver accuracy approaching the Incra system?*


As Terry Q correctly points out below, the Incra relies on a "positioning" system using a rack and pinion if I recall from having my friend demonstrate his to me. It is very "accurate" in that it will locate in precise increments when you "position" it. It will also be parallel to the miter slots, which is critical. 

Your Delta clone will not "position" itself incrementally, you must set it each time either by measuring from the blade to the fence OR by using a spacer block between them. It will also lock down parallel to the miter slots, IF it's at all like my Biesemeyer fence(s). The Wixey digital tape system comes as close as anything out there to position the fence without actually using a separate measurement each time you adjust the fence.

So, what's "accuracy" really mean in this context? It means repeatabilty as far as I can tell. 
Then here's the issue: Where is the accuracy desired, in the distance from the blade to the fence for getting the same thickness rip OR a repeatable offcut? You can't have both, because in one case the fence is stationary, in the other case, it's being moved and reset each time. If you don't move the fence each rip will be exactly the same ...... in my experience. If you move the fence for each rip, you must rely on a "bump" type jig to reposition it for each successive rip. That will typically get you very close, but there is some room for error IF the fence doesn't lock precisely each time. My Biesemeyer fences do, so not a problem for me.

I don't think you can "get there from here" and have the best of both worlds without sacrificing something .... either rail length and capacity OR hand positioning and measuring each time and or using a "bumping" system. You have to pick one or the other. :| 


Terry Q said:


> The Incra LS Positioning fence is unlike any other fence on the market.
> 
> *Once you understand how to use an Incra fence you’ll change the way you use table saw fences*. For instance, if you needed some thin strips, say 1/8 inch or less.
> 
> ...


Thanks for pointing this out, it led me to my conclusion above. :vs_cool:


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## DrRobert (Apr 27, 2015)

I’m not exactly sure what you’re doing but you can make a stop stick that registers off the table saw edge to the fence.

A small heel attached to the end is more accurate than feeling for flush. Clamp before setting fence.


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## Bernie_72 (Aug 9, 2020)

brucet999 said:


> That Incra LS is an impressive tool, but with 72" rails, too wide for my little Delta hybrid saw that has to fit in a 64" wide space along the wall of my shop/garage while not in use. The right side has a shop-made router table/extension.
> 
> Does anyone know of another good alternative to my Delta knock-off Beesemeier-style T-fence, that could deliver accuracy approaching the Incra system?


Although the incra rails come in a 72" and 92" variants they are easily cut down on a miter saw with a general purpose blade. I ordered a couple of extra incra rails which I cut to a custom length so I could place it on either side of my table saw to cover both router tables as well as my bandsaw. The incra base unit is moved easily and the different positions you want to use it at are fixed by a set of simple locks that you place wherever you want on the rails.

I have my fence mounted so I get the full 32" reach to the right of my saw blade. That puts the end of the positioner base about 44 1/2" away from the blade. So if your 64" space limit is only when you're storing your table saw you should be OK. That being said when you're actually using the fence and you want to take the full 32" cut the end of the positioner rail will extend out to almost 75" from your blade. 

One thing I didn't realize when I ordered the incra fence with a 52" reach is that incra uses the same positioner for their 32" reach setup and the 52" reach setup. No mater which option you choose the positioner itself will only provide 32" of reach. The 52" version just comes with longer rails and a few more positioner stops.


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## Bernie_72 (Aug 9, 2020)

brucet999 said:


> ... I realize that at 72" long rails, Incra gives only 32" of cut to the right of blade. Cutting off 10" of the rails would likely leave me with only 22" maximum cut. My old Delta T-fence gives me 31 1/2" cut and I don't have to remove it in order to run a router bit with a bearing on my right-side router table/extension.
> 
> I like the idea of precision, but spending $500 for 30% _less_ cut capacity doesn't much appeal to me.


That assumption is incorrect. The picture below is with 72" rails (sorry for the mess). I currently have the base mounted to take a full 32" cut but I have another 20" of rail behind the current position. I could get a 52" cut using the 72" rails if I wanted to with this setup.

I have a little longer reach with the 72" rails because I don't have an extension to the left of my table saw blade due to the slide I use. The reason that Incra sells 92" rails to support their advertised 52" cut is because most people have some sort of table extension to the left of their blade. 

When trying to decide what length of cut you'll get you just need to add about 12" to the length of the cut to account for the base. For instance to get a 32" cut the base is actually about 44 1/2" from the saw blade. If you want a 52" cut you'll need about 66" from the saw blade.


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## JohnGi (May 9, 2019)

*Cutting a duplicate*

I'll cut a duplicate piece to match one I already have without taking any measurements or trial and error adjustments using a scrap piece. 
I take the scrap, tape it to the original, set the saw fence to trim the scrap, and run them through as a pair.










Then I tape the new, oversized, piece to the scrap block, and without changing the fence setting run them through as a pair. The new piece is now the same width as the original.










I set the stop on the radial arm saw to trim the end of the scrap block with the original and the scrap set end to end against the stop.










After I trim the end of the scrap block, I set it and the new piece end to end against the stop.










After trimming, the new piece matches the original to the limits of the machine accuracy. This took about 10 minutes.


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## Dave Mills (Dec 4, 2019)

Brilliant, John. Thanks for the photos too, I wouldn't have been able to picture it without them!


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## TomCT2 (May 16, 2014)

the whole discussion boils down to being able to set the fence at a distance _exactly_ to match the "original width"
nothing more, nothing less.
fancy doodads like the Incra simply allow one to micro adjust the fence distance with less pain than loosening the fence lock.
it's not "more accurate" because you are trying to match an original dimension - not some number on a scale. 

it's not a question of "accuracy" - it's a question of "ease of control"


in my personal experience, the run out of a 10" table saw blade varies by mounting position. the variable run out can vary the finished cut dimension by 0.010" - bottom line: same blade mounted on same table saw with (assumed) same fence setting = different width ....
so basically there is absolutely no substitute for 'trial and error' - make a cut, check against original, move the fence as needed.....

I disagree to the utmost of putting "the original" on the table for "simultaneous" adjustment.  
any boo-boo of any amount that shaves something off the original leaves you without a reference.


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## brucet999 (Feb 23, 2019)

Bernie_72 said:


> I have my fence mounted so I get the full 32" reach to the right of my saw blade. That puts the end of the positioner base about 44 1/2" away from the blade. So if your 64" space limit is only when you're storing your table saw you should be OK. That being said when you're actually using the fence and you want to take the full 32" cut the end of the positioner rail will extend out to almost 75" from your blade.


I assume that the positioner base is the "guide box" with the red lever, mounted on that wide bar between the rails? How far do the rails extend to the right of that? The rails would be my limiting factor for fitting into the 64" wide space where I have to park the saw against the wall, unless the positioner rail extends beyond them.

Presumably, I could cut off parts of the rails on the left side flush with the saw table (20 1/4" from the blade). I guess that would limit left-side cuts to about 9", which is ok, since I don't think I have done a left-side cut in 15 years and that is about how much my existing fence allows anyway. 

The accuracy and repeatability of the Incra system appeals to me especially now that I have committed to making a couple hundred of my little secret boxes for Toymakers charity this year and maybe 500 next year, made in batches of 30 or so. The 5/32" thick sliding lids are cut off the 8/4 blanks before the insides are hogged out and the dovetail track is routed. They need to be accurate and uniform both for the dovetail depth to work, and also for the CNC flower design cut into the tops, so we have only one setup.


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## brucet999 (Feb 23, 2019)

Bernie_72 said:


> When trying to decide what length of cut you'll get you just need to add about 12" to the length of the cut to account for the base. For instance to get a 32" cut the base is actually about 44 1/2" from the saw blade. If you want a 52" cut you'll need about 66" from the saw blade.


Thanks, you explain this tool much better than the manufacturer does.

In the images, I saw a stop bolt in the rails as a limiter for mounting the big cross bar between the rails. How close to the end can that be set? 

That 12 1/2" figure you mentioned is a little unclear to me as to measured from-where-to-where. If I cut the rails to 62 1/4" (to allow about 1" space on each side when "parking" the saw in its wall space) mounting them flush with the left side of my saw table, the right ends of the rails would be 42" from the blade. Taking into account the stop bolt on the rail, the wide cross bar and "guide box" which locks the positioner bar, how wide a cut can I get to the right of the blade?


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## brucet999 (Feb 23, 2019)

TomCT2 said:


> in my personal experience, the run out of a 10" table saw blade varies by mounting position. the variable run out can vary the finished cut dimension by 0.010" - bottom line: same blade mounted on same table saw with (assumed) same fence setting = different width ....
> so basically there is absolutely no substitute for 'trial and error' - make a cut, check against original, move the fence as needed.....


Can you explain the mounting position for me? Are you saying that the saw's arbor may have runout and a blade removed, then put back on will have a different amount of runout than if it had before?


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## woodnthings (Jan 24, 2009)

*When checking for run out ....*



brucet999 said:


> Can you explain the mounting position for me? Are you saying that the saw's arbor may have runout and a blade removed, then put back on will have a different amount of runout than if it had before?



You can check for run out by rotating the blade and tightening it at 6, 9, 12 and 3 o'clock positions on the arbor. Secure the arbor by strapping the belt down or on a direct drive just make a visible white mark on the arbor backing washer and watch for it in those locations after you tighten up the blade. Likewise, place a small whiteout mark on a tooth to locate the position of the blade as well.


If the arbor has runout, there's not a whole lot you can do other than stone the backing washer's face while the saw is running. You Tube has videos which demonstrate how it's done. If the blade has runout, a sharpening service can flatten it OR you can just live with it. Find the position on the arbor where it is the least and just use it in that position when making blade changes.








:vs_cool:


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## TomCT2 (May 16, 2014)

if you have (what one perceives to be..) excessive run out - loosen the arbor nut, keep shaft/arbor stationary, rotate blade 90 degrees, re-tighten arbor nut and recheck run-out. repeat as needed - although the 4th 'peat gets you back to where you started....


my theory: super small variations in thicknesses - especially if the arbor area has be decorated/painted/printed/coated - can translate to noticeable run-out at the saw teeth radius..... rotating the blade simply finds the least disruptive position. I've "replicated" the issue and the solution on multiple blades over multiple times - (same table saw) - so there seems to be something to it.


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## brucet999 (Feb 23, 2019)

That makes sense. Every blade has some amount of runout, and if there is slight runout in the arbor, then rotating the blade on the arbor may find the point where one tends to cancel the other.


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## JohnGi (May 9, 2019)

"If the arbor has runout, there's not a whole lot you can do other than stone the backing washer's face while the saw is running. You Tube has videos which demonstrate how it's done."

I watched the video. I think the author was premature in attributing the runout to the shape of the arbor (the flange not being square to the arbor's axis) rather than the motion of the arbor (the axis of the arbor is not aligned with the axis of rotation, so the plane of the flange is not square to the axis of rotation). I've found the later condition more common.

If one of the bearings is not pressed onto the arbor square or if a bearing is worn unevenly, the center of rotation at that point is thrown off. The arbor will appear to wobble or flutter as it spins. Long spindles act as if they are bent, which would be a problem you can't do anything about. I've never seen a bent spindle, but I've corrected spindles people thought were bent by resetting the bearings.

Grinding a flange to true it will certainly work, but it is more likely that it addresses the symptoms of the problem rather than the root cause.


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## woodnthings (Jan 24, 2009)

*Unlikely in my opinion ....*



JohnGi said:


> "If the arbor has runout, there's not a whole lot you can do other than stone the backing washer's face while the saw is running. You Tube has videos which demonstrate how it's done."
> *
> I watched the video. I think the author was premature in attributing the runout to the shape of the arbor (the flange not being square to the arbor's axis) rather than the motion of the arbor (the axis of the arbor is not aligned with the axis of rotation, so the plane of the flange is not square to the axis of rotation).* I've found the later condition more common.
> 
> ...



The arbor and flange are machined in a single lathe operation. It is highly unlikely the flange is NOT perpendicular to the center of rotation of the arbor. However, it may have some minor runout like 0.005" like in the video. If there is any doubt, this process is easy enough to accomplish and may be worthwhile regardless.

If the arbor is not at 90 degrees to the miter slots, this is an adjustable condition which I have done several times with different types of table saws. I speak with "limited" machining experience having only a 13" and a 9" South Bend metal lathes. 

A wobbly arbor due to a worn or misaligned bearing would express itself instantly. A grossly out of true flange would be exhibited by a wobbly blade, also instantly visible. How a 5/8" arbor would get bent is beyond me. :surprise2:


A different flange, not arbor truing video:


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## Bernie_72 (Aug 9, 2020)

brucet999 said:


> Thanks, you explain this tool much better than the manufacturer does.
> 
> In the images, I saw a stop bolt in the rails as a limiter for mounting the big cross bar between the rails. How close to the end can that be set?
> 
> That 12 1/2" figure you mentioned is a little unclear to me as to measured from-where-to-where. If I cut the rails to 62 1/4" (to allow about 1" space on each side when "parking" the saw in its wall space) mounting them flush with the left side of my saw table, the right ends of the rails would be 42" from the blade. Taking into account the stop bolt on the rail, the wide cross bar and "guide box" which locks the positioner bar, how wide a cut can I get to the right of the blade?


Sorry for the delay in answering your questions. I thought it would be more helpful to post a video for you rather than trying to answer them in a post. The video below goes through a few items that I think should answer your questions. If not let me know and I'll do my best to get you the answers you're looking for.

The measurements I mention in the video are always from the blade. So when you're trying to figure out whether this will work for your saw or not you'll have to take that into account. If I understand your question correctly if you have 42" of space from the blade to the right ends of the rails you'll probably be able to get around a 29" cut. My base is mounted exactly 42" from the blade and I get just under 30 1/2" cut. Since the locking bolts are about 1.5" long you won't quite be able to use that entire 42".

One other note...in the first part of the video I show the measurement from the blade to the end of the positioner. I say it's 43 1/4" from the blade to the farthest point of the positioner. I misspoke...it's actually 43 3/4" to that bold that sticks out of the end of the positioner.


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## woodnthings (Jan 24, 2009)

*This title got me to thinking .......*

Why not have a "powered" fence like a milling machine's "X" axis.
It could be manually set with a hand crank OR driven with a servo motor to precisely the exact same dimension every time. Talk about accuracy! :surprise2:


Wait ..... there must be such a saw in industry where time is money and accuracy is paramount. Sure enough, Grizzly has one. All I need is the 15 K, 3 phase wiring and a bigger shop..... :sad2:
https://www.grizzly.com/products/Gr...liding-Table-Saw-with-DRO-and-CNC-Fence/G0853


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## brucet999 (Feb 23, 2019)

Wow! You really went all out with that video. The only way it could have been clearer would have been to teleport me to your shop for a hands-on lesson.

Your measurement to the end of the bolt is the limiting factor for having sufficient room to get into my saw's "parking place". So 62" rails (minus 1" stop bolt) would give me 62 3/4" width overall, counting the bolt on the end of the positioner, leaving 1 1/4" of clearance to maneuver into the 64" space on the wall. 62 3/4" overall = 42 1/2" right of the blade, giving me a max 29" right-side cut width. 

To describe my situation, one picture is worth 1,000 words:


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## brucet999 (Feb 23, 2019)

Using a 28" x 21" router table on the right, which is the only place it can go, would require, at a minimum, re-positioning the TS-LS base 20" to the left in order to gain access to the router table, correct? Or reversing the fence system if I need a router fence. That would be something of a nuisance, but doable.


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## Bernie_72 (Aug 9, 2020)

brucet999 said:


> Using a 28" x 21" router table on the right, which is the only place it can go, would require, at a minimum, re-positioning the TS-LS base 20" to the left in order to gain access to the router table, correct? Or reversing the fence system if I need a router fence. That would be something of a nuisance, but doable.


I'm glad the video helped. Incra doesn't do a great job of describing their products. There are a lot of good videos on youtube that go over the functionality of the system but I couldn't find any that got into details on the measurements. 

Looking at the picture it appears that you would have room to use the router table with the incra positioner set to the right of it. If that's a 22' wide base with the router mounted offset to the left, I'd guess that you have more than 12" from the router spindle to the right side of the table. If you can can extend the positioner base a few inches past your router table you should have enough room for the normal incra fence along with the wonder fence (for your router). The wonder fence attaches to the incra table saw fence and adds another 3 3/8" (see picture). That can be purchased at a discount with the joinery package or it can be added later.

The only drawback with using the incra system for your router is that you can't work from the end of the router table, you end up working on the left side of the fence. You can see in the picture below that I rotated my router lift 180 degree so the controls are on the left side. It's not as comfortable as working off the end of the router table but with the additional control that comes from the fence and slide it has helped improve my routing accuracy. Apart from that the dust collection is very good.

One thing I forgot to mention is the long lead time for these LS/TS systems. The website shows a 15 to 18 week estimated lead time. That was about what it took for mine to come in. I ordered it in early April and it arrived at the end of July. That was right in the middle of the COVID feed home improvement project rush so perhaps the lead time might be better for you.


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## brucet999 (Feb 23, 2019)

"Looking at the picture it appears that you would have room to use the router table with the incra positioner set to the right of it. If that's a 22' wide base with the router mounted offset to the left, I'd guess that you have more than 12" from the router spindle to the right side of the table."

Thanks again for the video and for this latest response.

No, my homemade router table is 27" x 15", flush with the back rail, and I find it convenient to work from the end rather than from the front. If I'm not mistaken, I should be able to move the base to the left until the fence reaches the left side of the saw table, leaving the insert of an Incra 28 x 21 router table and about 12" of table clear to work from the end when using bearing bits. 

For router fence work, I would have to rotate the whole fence system. Not a big deal, since I presently have to take time to mount and clamp my crude shop-made fence adapter to my T-fence anyway.

That lift is fairly pricey, BTW. Do you find it substantially better than reaching underneath for the height adjustment of the router itself? As I think of it, it might be worth it just to be able to access the collet nut from above.


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## Bernie_72 (Aug 9, 2020)

brucet999 said:


> Thanks again for the video and for this latest response.
> 
> No, my homemade router table is 27" x 15", flush with the back rail, and I find it convenient to work from the end rather than from the front. If I'm not mistaken, I should be able to move the base to the left until the fence reaches the left side of the saw table, leaving the insert of an Incra 28 x 21 router table and about 12" of table clear to work from the end when using bearing bits.
> 
> ...


I misunderstood your router table measurements before so you are correct, you would want to move the incra fence to the left when working on the router table.

All the Incra stuff is expensive but it is good quality. Before I started building out my own shop I worked at a friends wood shop. He had a Jessem lift that I really enjoyed working with. I was initially going to purchase the Jessem Master Lift 2 but the structure under the grizzly cast iron router table top made it more advantageous to go with the smaller Incra version. The incra dimensions are about an inch sorter than the Jessem lift. I had the cast iron top CNC'd out to fit the lift. If I had used the Jessem I would have had to cut some of the cast iron support structure, but with the Incra being 1" shorter I was able to leave all that support structure in-place under the table.

The Incra lift is just a rebranded Jessem master lift 2. There are a lot of good router lifts out there and quite a few are less expensive than the Jessem/Incra option. In the end I decided to go with something I already had experience with and so far I've been happy.

I find it handy to have the adjustments above the table. Being able to change the router bits above the table and being able to make precise height adjustments above the table is handy. I have an enclosure for the router as well so changing the bit or making height adjustments would be even more of a pain if I couldn't do it above the table.


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## brucet999 (Feb 23, 2019)

Thank you, @DaveMills, for launching this thread. 

Some of the answers to your questions introduced me to Incra TS-LS, that will give me repeatable accuracy for my secret boxes project and add a top-notch router table/fence/lift system to my little Delta Hybrid saw.. 

I was also inspired to find out that the trunnion of my saw was mis-aligned. After correcting that, and properly aligning my fence, I now get perfectly clean cuts without any contact of the rear teeth as the work passes through the blade. 

All because you asked a question.


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