# 5 Cut Cross Cut Sled Fence tolerance



## bryansong (Mar 4, 2015)

I'm referring to the 5 cut method.

I've been trying to zero in on the fence being square and boy has that been a bugger. I've drilled so many holes under it I'm running out of places to drill (this is just a small sled). 
I did have it down to around .001"s but when I put in the rest of the support screws it ended up being .0027". 

My question, is that good enough?

Bryan


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## gjackson52 (Jul 4, 2015)

Given how much wood can move with seasonal changes, I would think it is fine.


Gary


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## bryansong (Mar 4, 2015)

Thanks Gary.

Maybe I'll turn the sled around making the back the front and try it again later. I need a break right now, I'm tired.


Wait, I do already have the back on mounted with several screws. I'll have to look at and see if I have more room for holes.


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## DaninVan (Jan 1, 2012)

Bryan; I think the simple solution is to use a small slot in one of the components allowing the fence to pivot slightly. When you get it where you want it you tighten it down, and put in the remaining screws to lock it in place.
Essentially two screw holes and one slotted hole, in the length of the fence.


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## bryansong (Mar 4, 2015)

DaninVan said:


> Bryan; I think the simple solution is to use a small slot in one of the components allowing the fence to pivot slightly. When you get it where you want it you tighten it down, and put in the remaining screws to lock it in place.
> Essentially two screw holes and one slotted hole, in the length of the fence.


I'll look at that idea and see if I can do it. I did have it dialed in at around .001"s but it didn't hold when I put in the other screws. Maybe the two screws weren't tight enough. I would like to get it closer so I'll try it again. 
My base isn't very big so I'll look at what Baltic Birch I have left in case I need to start over.
I'm also building a large sled and what I learn with the small one should help there.

Thanks for the suggestion,

Bryan


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## DaninVan (Jan 1, 2012)

*Bogglement*
Bryan; are you saying your tolerance _after_ doing the 5 cuts is +/- .001" ?!
Holy Hanna! You wanna make me one? Please!!


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## Quillman (Aug 16, 2010)

Stop!
I'm doing a treatise on measurement and woodworking.
There are so many variables with respect to this squaring method; don't waste your time.
You cannot measure wood to .001".
There is stress relief, fuzz, dust, face tearout, saw chatter +....all frustrate getting the same measurement twice in the same place.

Your vision, parallax, your measuring tools and your skills at reading (& using) them play a part. Do you read from the centerline of the fiducials (rule etchings), the space in between, or both. It makes a difference. Starrett rules are calibrated on the line centerlines. The space between the lines, depending on the increment, is only an estimation! Calipers, travel and ht. gages are accurate but is your work cut accurately enough to use them? Is the work flat, measured on a reference surface, etc?

Moreover, the health of your saw system, saw blade (twisting/bending, sharpness), feed rate and the anisometry (directional dependency) of wood are dependent variables to contend with too. The dynamics of the saw blade in a x-cut are different than a rip. This is crazy.

Just set your sled to squareness (as best you can) and take a cross cut on something 8-12" wide, starting with a very straight edged & precisely parallel stick. The fence on the sled has to be within +/- .001 or better in flatness and straightness for starters. The work has to be clamped; it cannot squirm. Use a machinist's square on the cut stock and do your best to investigate it.

Check this from time to time, maybe keep samples and dates, but don't get crazy over this foolish squaring technique; it's a guess.


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## bryansong (Mar 4, 2015)

DaninVan said:


> *Bogglement*
> Bryan; are you saying your tolerance _after_ doing the 5 cuts is +/- .001" ?!
> Holy Hanna! You wanna make me one? Please!!


Dan, not exactly but I had at .001 until I added more screws for support, that's when it moved to .0027"s. I used Dr Ny's video for the 5 cuts and adjusting.

On another note here-
Below in this post I found this and pasted it here from Quillman and I'm mentioning it here because I couldn't see this post while just reading all of the other post. I only saw it after I quoted you Dan, then I ran down the page and saw Quillman's reply.
I'm wondering if this has happened before, maybe I've missed other post.

Can you or anybody else see Quillman's post in the main body of the string of replies?

Here's is what I cut and paste from Quillman's post.

"Quillman Stop!
I'm doing a treatise on measurement and woodworking.
There are so many variables with respect to this squaring method; don't waste your time.
You cannot measure wood to .001".
There is stress relief, fuzz, dust, face tearout, saw chatter +....all frustrate getting the same measurement twice in the same place.

Your vision, parallax, your measuring tools and your skills at reading (& using) them play a part. Do you read from the centerline of the fiducials (rule etchings), the space in between, or both. It makes a difference. Starrett rules are calibrated on the line centerlines. The space between the lines, depending on the increment, is only an estimation! Calipers, travel and ht. gages are accurate but is your work cut accurately enough to use them? Is the work flat, measured on a reference surface, etc?

Moreover, the health of your saw system, saw blade (twisting/bending, sharpness), feed rate and the anisometry (directional dependency) of wood are dependent variables to contend with too. The dynamics of the saw blade in a x-cut are different than a rip. This is crazy."

Just set your sled to squareness (as best you can) and take a cross cut on something 8-12" wide, starting with a very straight edged & precisely parallel stick. The fence on the sled has to be within +/- .001 or better in flatness and straightness for starters. The work has to be clamped; it cannot squirm. Use a machinist's square on the cut stock and do your best to investigate it.

Check this from time to time, maybe keep samples and dates, but don't get crazy over this foolish squaring technique; it's a guess.


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## bryansong (Mar 4, 2015)

Quillman,

Sorry Quillman, I can't see your post in with the other post. I did see it when I started to reply to Dan with his quote, that's where I saw your post.

Is a machinist square one of those little squares with no writing on it (maybe 6")? Well, it may have writing but from seeing them in pictures 
they look like there's nothing on it.

Anyway, is that what you think I should be doing instead of going through this 5 cut and calculation process?

Bryan


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## bryansong (Mar 4, 2015)

Ok everybody, sorry, now I see Quillmans post. It must have been lost in space.


Bryan


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## schnewj (Nov 18, 2013)

bryansong said:


> Ok everybody, sorry, now I see Quillmans post. It must have been lost in space.
> 
> 
> Bryan


Bryan, Pat has some sage advice. It amazes me, that, woodworkers try and hold their dimensions to the same tolerances as a machinist! While I, like others, tend to hold to as tight a fit as I can it is not all that critical.

The diameter of human hair varies from 17 to 180 micrometers (0.00067 to *0.00709* in). 

0.001" is seven times finer then the size of a thick human hair.

Guess what? Glue, sawdust and finish can fill this void and no one but you will ever notice or even care.


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## Stick486 (Jan 4, 2013)

schnewj said:


> Bryan, Pat has some sage advice. It amazes me, that, woodworkers try and hold their dimensions to the same tolerances as a machinist! While I, like others, tend to hold to as tight a fit as I can it is not all that critical.
> 
> The diameter of human hair varies from 17 to 180 micrometers (0.00067 to *0.00709* in).
> 
> ...


excellent analogy...

.









.


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## woodknots (Mar 7, 2012)

Quillman said:


> Stop!
> I'm doing a treatise on measurement and woodworking.
> There are so many variables with respect to this squaring method; don't waste your time.
> You cannot measure wood to .001".
> ...


Pat: every woodworker that agonizes over their crosscut sleds or tolerances in general needs to read your post.

Bryan:

I posted some pics in another thread of yours. It's the method I used when I made my sled. I lock down one end of the sled's fence, then using a dial indicator and a machinist square on the "loose" end, I slide the sled so that the machinist square rides along the dial indicator. If the indicator *barely* moves, I lock down that end of the fence. Good enough for my woodworking.


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## DaninVan (Jan 1, 2012)

Bryan; you probably made the connection between 'Quillman' and Pat Warner, but just in case you had any doubts about Pat's uh, experience...
ROUTER WOODWORKING

When it comes to precision, he's a Guru!


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## PhilBa (Sep 25, 2014)

At .0027, I'd call it good. William Ng tries for .001 (1 mil) but in one of his videos, he admits that a couple of mils isn't worth sweating over.

I'd worry over 10 mils, work to get 5 mils out but 1 or 2, you are at the point of diminishing returns.


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## bryansong (Mar 4, 2015)

PhilBa said:


> At .0027, I'd call it good. William Ng tries for .001 (1 mil) but in one of his videos, he admits that a couple of mils isn't worth sweating over.
> 
> I'd worry over 10 mils, work to get 5 mils out but 1 or 2, you are at the point of diminishing returns.


Thank you Phil. Dr Ny did say not to sweat it but in the video I saw I didn't pick up on just how tight it should be.

Bryan


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## bryansong (Mar 4, 2015)

vchiarelli said:


> Pat: every woodworker that agonizes over their crosscut sleds or tolerances in general needs to read your post.
> 
> Bryan:
> 
> I posted some pics in another thread of yours. It's the method I used when I made my sled. I lock down one end of the sled's fence, then using a dial indicator and a machinist square on the "loose" end, I slide the sled so that the machinist square rides along the dial indicator. If the indicator *barely* moves, I lock down that end of the fence. Good enough for my woodworking.


Vince, I found your post in that marathon thread "Table Sled Runners" and I understand how you do it, it did make sense.
I did pick up a dial indicator but no mounting hardware yet so I'll have to get to that as well as getting a machinist square.

Bryan


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## bryansong (Mar 4, 2015)

DaninVan said:


> Bryan; you probably made the connection between 'Quillman' and Pat Warner, but just in case you had any doubts about Pat's uh, experience...
> ROUTER WOODWORKING
> 
> When it comes to precision, he's a Guru!


Dan,

Nope, I didn't make that connection though I did recognize his site from the link, I have been there. I saved it to Favorites for future reference. I still don't have everybody figured out.

Thanks for the clarification and the link.

Bryan


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## woodknots (Mar 7, 2012)

Bryan

If you've got the dial indicator, mount it on a wooden runner - here's a link to a site that shows you how:

Dial Indicator Jig - NewWoodworker.com LLC

You don't need a machinist square - you must have a combination square in your shop. Just make sure it "is square". You can check it by the reverse method. First put your square against an edge and strike a line, then flip the square, strike another line close to the first line. If the two lines are parallel, then your square is "square".

You don't need fancy equipment, you just need to improvise.


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## bryansong (Mar 4, 2015)

Good information Vince.

Thanks


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## DesertRatTom (Jul 3, 2012)

bryansong said:


> I'll look at that idea and see if I can do it. I did have it dialed in at around .001"s but it didn't hold when I put in the other screws. Maybe the two screws weren't tight enough. I would like to get it closer so I'll try it again.
> My base isn't very big so I'll look at what Baltic Birch I have left in case I need to start over.
> I'm also building a large sled and what I learn with the small one should help there.
> 
> ...


Pre drilling and counter sinking the screws while the fence is aligned and clamped in place is a must. You might try putting some slivers of hard wood into the holes opposite the side that's off to see if that will move you more in alignment. 

I've been trying to get my picture frames cut to a perfect 45 miter. My new miter jig didn't get it, and after many attempts and trials and error, I realized the blade was getting slightly deflected so the miter looked fine, but was slightly bulged so the frame wouldn't close up.

Finally put in a full kerf blade that would never deflect, then recalibrated my Rockler sled to the body of the blade, not the fence. Voila. The four corners finally align. It is amazing how small the error was, about 1/5th of a degree, but multiply that by four and you have a frame that won't line up sufficiently to glue.

I suggest that you also do your alignment to the blade. I got a Rockler quarter inch thick, large draftsman triangle that has both a 45 and 90 degree angle Woodworker's Triangles - Rockler Woodworking Tools. I laid it on the sled, slid it over to the blade and lodged it against the body of the blade, avoiding the teeth. I raised the blade most of the way up, to get as much contact as possible. Once that was set up, it was pretty simple to set the fence in perfect alignment with the triangle. On the Rocker sled, I had to reset the line on the magnifier with the 45 degree mark on the sled.

That's pretty much what you have to do, except you'll be setting the fence to 90 degrees. 

One last thing, I am using tapered drill bits with countersinks to pre drill holes. Seems to work better than a straight bit for me. I suspect the problem has to do either with not pre drilling, or by drilling with a straight bit at an angle, which would leave the countersink at an angle that would have it pull to one side. Getting the pre drilled hole as close to 90 as possible would help as well, but the tapered bit has pretty much eliminated pulling the work piece out of alignment for me.


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## Stick486 (Jan 4, 2013)

do counter bores instead of countersinks and use truss head style screws instead of flat heads...

do the counter bores and clearance holes in the runner(s)...
set your runner in the miter slot counter bores down...
DS tape on the tops of the runner(s)...
set the sled on the runner(s)...
flip the sled upside down...
install the the truss headed screws...

want perfect miters...
get a Lion miter trimmer...
well worth the money and perfect miters are no sweat..


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## DesertRatTom (Jul 3, 2012)

Thinking further about this, since the fence is probably shifting when you move it to drill, perhaps you could drill a hole down through the top of the fence- (but not into the base), slightly smaller than a long finish nail, align the fence, then lock it in place by hammering in the finish nail. Then when you move it it will really stay put while you drill through from below. Once set, pull out the nail.

Don't forget to make sure your blade is at 90. Use a Wixey to set that angle. 

Have you also made certain your fence is 90 to the table? Small errors seem to multiply themselves.


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## cocobolo1 (Dec 31, 2015)

Bryan...really, two point seven thousandths of an inch and you're worried? I'd say you're golden! :smile:


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## Rogerdodge (Apr 24, 2014)

Loving the "fiducials" may I have them please ?


Roger


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## hawkeye10 (Jul 28, 2015)

Bryan after all that trial and error you must be wore out and tense. Take a road trip to Tennessee and we will get a jug of moonshine. It will work wonders to calm you down and help you think straight. :laugh2:


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## DonkeyHody (Jan 22, 2015)

I've been in your shoes. I finally gave up on getting my sled fence dead on. I used clear packing tape to attach playing cards to the fence to bring the workpiece into perfect alignment. It seems to work fine and was a lot less frustrating if not so elegant looking. 

Speaking of playing cards - once I took a couple of old decks out to the shop, I found a multitude of uses for them. Y'a know how you sometimes need to work some glue down into a crack? Cut a strip off the end of a card. The playing card stock doesn't soften upon contact with the glue like paper does. And I use them for shimming absolutely everything. Another very handy thing to have around is a set of plastic door shims. They just seem to find their own uses.


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## Shop guy (Nov 22, 2012)

I use playing cards, business cards anything thin and durable. Sometimes just makes life easier.


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## Quillman (Aug 16, 2010)

"Is a machinist square one of those little squares with no writing on it (maybe 6")? Well, it may have writing but from seeing them in pictures
they look like there's nothing on it."
************************************************************
Yes & no. The cheap ones are not identified, no markings.
The term (machinist's square) is vague: I should not have used it.
Starrett calls it a master square, they're good to better than .0005"/6" in straightness and squareness. Mitutoyo calls them Engineer's squares, others call them toolmaker's squares.

Better you select one that has name and numbers behind it. They're expensive, a 6" beamed square might be 3-500$, but a life time tool, nevertheless. Dependable Metrology (the study of measurement) tools are expensive, a life long investment. The thing: If you want to track and locate errors you have to spend.

Woodworking tools are still in the dark ages. It's not uncommon for woodworking stationaries to have calibration adjustments that cancel or frustrate the next one. 
The quickest way to accurate woodworking is to measure, cut and adjust, ignoring the set up procedures in the manual. But, to be sure, start where the manual's set-up leaves off. You don't want to adjust the machine into an unsafe calibration. Moreover, your practical re-adjustments should be close to the manual's. These machines just don't have the mass, precision, adjustment capability, and calibration capacity of machine tools. 

And, of course, learn how to measure. Where? I haven't the slightest. It, like precision drilling, is not taught. A shame but true.


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## bryansong (Mar 4, 2015)

DesertRatTom said:


> Thinking further about this, since the fence is probably shifting when you move it to drill, perhaps you could drill a hole down through the top of the fence- (but not into the base), slightly smaller than a long finish nail, align the fence, then lock it in place by hammering in the finish nail. Then when you move it it will really stay put while you drill through from below. Once set, pull out the nail.
> 
> Don't forget to make sure your blade is at 90. Use a Wixey to set that angle.
> 
> Have you also made certain your fence is 90 to the table? Small errors seem to multiply themselves.


Tom, I haven't check that lately but whenever I do use the bevel I do reset the blade to 90° then. I don't have a Wixley for that but I do have a Wixley blade height gage that is only 1 year old that no-longer works, I can't zero it. I'm not too impressed with it.


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## bryansong (Mar 4, 2015)

hawkeye10 said:


> Bryan after all that trial and error you must be wore out and tense. Take a road trip to Tennessee and we will get a jug of moonshine. It will work wonders to calm you down and help you think straight. :laugh2:


Don, thank you for that suggestion and offer, I've never tried moonshine but I do watch the show. 

Bryan


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## MEBCWD (Jan 14, 2012)

Bryan,

A piece of aluminum will change in size that much with weather changes or even after being milled.

Quit nit picking and start building a project with that sled. 

Work Safe, Have Fun, Cut Some Wood!


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## bryansong (Mar 4, 2015)

DonkeyHody said:


> I've been in your shoes. I finally gave up on getting my sled fence dead on. I used clear packing tape to attach playing cards to the fence to bring the workpiece into perfect alignment. It seems to work fine and was a lot less frustrating if not so elegant looking.
> 
> Speaking of playing cards - once I took a couple of old decks out to the shop, I found a multitude of uses for them. Y'a know how you sometimes need to work some glue down into a crack? Cut a strip off the end of a card. The playing card stock doesn't soften upon contact with the glue like paper does. And I use them for shimming absolutely everything. Another very handy thing to have around is a set of plastic door shims. They just seem to find their own uses.


I like that idea. Thanks!


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## bryansong (Mar 4, 2015)

Quillman said:


> "Is a machinist square one of those little squares with no writing on it (maybe 6")? Well, it may have writing but from seeing them in pictures
> they look like there's nothing on it."
> ************************************************************
> Yes & no. The cheap ones are not identified, no markings.
> ...


Pat, thanks for the clarification. 
I am an Electronic Equipment Technician and I repair and calibrate Electronic Test Equipment. I work for Honeywell in the Aerospace Division in the Nuclear Weapons Complex and have been employed here for 39 years. We have a Metrology department right next to me and I work with them on a daily basis. There is also a gage department next to Metrology though I haven't really had much to do with them. I do have measurement experience electrically but mechanically not so much other the my tape measure and such tools at home. I do have a set of caliper and greatly appreciate them. I do like accuracy though I am not very good at achieving it.
I try.

As for the square, I've been wanting one of those for some time but I'm not ready to spend the money on a good one. I do tend to go for the more expensive stuff even-though I won't use it frequently.
I am going to get myself one of those squares some day.

Precision drilling, I wish I were better at that.

Thanks,
Bryan


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## Stick486 (Jan 4, 2013)

bryansong said:


> Tom, I haven't check that lately but whenever I do use the bevel I do reset the blade to 90° then. I don't have a Wixley for that but I do have a Wixley blade height gage that is only 1 year old that no-longer works, I can't zero it. I'm not too impressed with it.


use drafting triangles...
more gooder...


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## bryansong (Mar 4, 2015)

I got a more gooder one too.


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