How square is square enough?

[Dan McGonigle]

Started on a workbench build recently. Dimensioning 12/4 poplar for the base. Face joint - thickness - edge joint - rip. Pretty standard. I squared my jointer fence to the bed using my 12” Starrett combo square. Similarly, I squared the table saw blade to the table using the Starrett. When all was said and done, I found that I had two 90 degree edges and two edges that were slightly out of square. These pieces are 2 3/4” by 3” and 4” for reference. After thinking it over, and checking all my setups agains, I came to this conclusion - when having to rip thick stock, I typically rip it on my bandsaw, 1/16 or 1/32 oversize, then clean up the edge on the table saw. I know this seems like extra work, and it is, but I hate pushing thick stock over my 2hp table saw and hearing it bog down and struggle. My bandsaw equipped with a 3tpi resaw blade goes right through 3” stock with ease. So I concluded that ripping 1/32” or 1/16” off the edge of a board is causing my table saw blade to deflect away from the workpiece, considering there’s nothing on the other side of the blade to counteract the deflection. To test this, I ripped my workpieces thinner, just by a few thousandths. This time, in an attempt to reduce the amount of deflection, I pushed the stock through very very slowly - ending up with some burn marks - but alas - the piece came closer into being perfectly square. Using my Starrett and feeler gauges, I found that some pieces are out of square by 0.002” over 3”-4”. I’m satisfied with that. I wish it was perfect, but it may just be the limitations of my machines. I often have to remind myself to not become obsessive over chasing “square”.

Bottom line. 0.002” over 3”. Is that square enough for you?

[Brian Holcombe]

Plane it to size.

A combo square is not uncommonly out of square, so if you are using that to square your machines then you may be doubling your error.

[Phil Gaudio]

You are approaching the practical limit to woodworking measurement. Yes, this would be square enough for me.

[glenn bradley]

Generic answer is that if it is square enough for what you are building, it is square enough. Just to confirm your bandsaw ripping protocol . . . You joint a surface flat, then joint a surface square to that. You then put the flat surface on the table of the bandsaw and the perpendicular (square) surface to the fence and rip at the tablesaw. I tend to true-up bandsawn surfaces at the planer using the opposite flat side (that was riding the bandsaw's fence) as my reference surface but, there are several ways to get to where you want to go.

Even more important in avoiding an endless trip down the black hole of perfection; wood moves. Even if your machines are perfect to a machine-shop level of alignment, the resulting material may not reflect this perfectly ;-) Don't get me wrong. I am one of those guys that aligns to .001" whenever possible. I like to have my machines as close as I can get them. That way I know if there are deviations it is technique or the simple movement of stress release in the material. This is why I (and others I am sure) approach milling material as a multi-step process. I mill to oversize and let things rest. I then mill to final dimensions very shortly before I assembly things.

[Frank Drackman]

I layout all of the boards that I am going to glue into a panel, put the cabinet makers triangle on them, and mark each edge of the joints alternately out/in. I go to the jointer and run each edge away from the fence or toward the fence. This cancels any error that my jointer fence is not exactly 90 degrees.

[Patrick Walsh]

The answer is as my new boss saiz “it’s either square or it’s not”.. and I totally agree.

Out of square compounds. It’s not that hard to make things square unless you are building stuff that kinda trash to begin with. I’ve build miles and miles of cabinets “not furniture” face frame style and it’s out of square slightly like 90% of the time as there’s no real joinery. Just all screws and glue and aligning stuff the best you can by feel and with clamps..

[Andrew Hughes]

I remember a time when was starting out . Nothing was square my saw wouldn’t cut straight or square none of my tools could measure square. My bench wasn’t flat. I couldn’t find a square corner on anything.
But I endeavored to persevere now my cutoffs and work pieces are pretty good. And if I really try I can make something square big or small.
Sometimes smaller stuff is harder because I have to use hand tools.

[Robert Hazelwood]

I agree with Brian that the planer is a better tool for dialing in the width for this size part. I use the planer for this whenever I can.

To your general question, is 0.002" over 3" square enough, it depends. It will work for many things, but would be a problem for others.

[Dan McGonigle]

I agree with Brian that the planer is a better tool for dialing in the width for this size part. I use the planer for this whenever I can.

To your general question, is 0.002" over 3" square enough, it depends. It will work for many things, but would be a problem for others.

I had thought about using the planer to dimension the width, but the length of these pieces are so close to their finished length, any bit of snipe would be a big problem. I try to rely on hand tools when accuracy is paramount, like in small or delicate pieces. In reality, I could take a few plane shavings off these boards and probably dial them in closer to perfection. The parts I'm working on are for a workbench base, so I think the level of square is acceptable. It just annoys me when I triple check all my machines and end up with anything other than perfect. Like I said before though, it may just be the limitations of my tools.

[Ryan Yeaglin]

Plane it to size.

A combo square is not uncommonly out of square, so if you are using that to square your machines then you may be doubling your error.

While this might be true of a common square from the hardware store, A Starrett square is a precision square. Although dropping one will take it out of square.

.002" of an inch is less than common machine shop tolerance =/- .005, So I would say it's fine unless your building a space shuttle. Wood moves way more than that from seasonal changes in humidity.

[Jim Becker]

Ryan, yes Starrrett squares that are kept carefully can be pretty accurate, but please trust that Brian knows what he is talking about when it comes to machine setup including in a machine shop! Check out his metrology thread when you have the chance. A combo square due to its nature can have some variance. I agree that on the wood side it's not such a big deal because as you note, wood is an ornery thing. But cast iron and steel are different and that little bit of variance cane absolutely affect machine setup. A fixed, high quality square is better for that task as a result.

OP, I also tend to dimension width using the planer.

[Bob Jones 5443]

How long are the parts? Why not use a cambered hand plane to get them square?

Wait: who let the Neanderthal in?

[Dan McGonigle]

How long are the parts? Why not use a cambered hand plane to get them square?

Wait: who let the Neanderthal in?

The parts are 24" and 33" long. The parts in question are what I'm calling the "feet" and "shoulders" of the bench base. I have the vertical leg members to mill next, gonna try taking to width in the planer. Even if I get some snipe, the ends will be cut into tenons, so it won't matter.

My No.4 will lightly touch all the parts before assembly. I could swipe a plane over these parts to true them to dead square, I'll see how I feel when I'm in my shop next.

[Patrick Walsh]

Yeah, you shouldn’t trust Brian.

He is rank amateur at best.

[Mark Hennebury]

Depends what you are doing.

I you skim a 1/16th off on edge on the table saw the blade will deflect.
If you rip stock for a table top at 91 degrees and flip the next board they fit perfectly.
If you want "Square" use the jointer.

Tip:
If you want accuracy,

Don't trust anything or anyone...ever!

Check and verify!

Don't trust any square or other tool regardless of the price or pedigree, if you can't check and verify it's accuracy.

For most operations you don't need any tool to check and verify.

Learn to how to check and reference.

Mark the face and edge of all of your stock.

Joint two pieces of stock flat, on the wide face, mark them as faces.
Joint the edges of both, mark them as edges.
Place the two faces on the flat jointer table top, place the two jointed edges together.
If they touch perfectly you have 90 degree edges and your fence is perfectly ninety degrees to your table.
If not you will see a gap at the top or the bottom that is double the error of your fence.

If your stock face is wide, place the two edges on the jointer and the two faces together, the error will be even larger.

No measuring equipment necessary.

You can obtain a high degree of accuracy with woodworking if you so desire.... but like everything else you have to create the environment to achieve it, and understand the variables.

Accuracy importance is dependant of what you are doing, how complicated it is, what is dependant on it, and who you are and what you care about.

Oh yes, and while I'm at it the old "it doesn't matter because wood moves" statement is pure crap. Metal also moves, and so does the granite that they use for all of the ultra high tolerance metrology equipment, like surface plates.

Use and Care Of Granite Surface Plates – Maintenance Tips

Cleaning and moisture:


One of the first principles of use and care of Granite Surface Plates is that you should clean the plate thoroughly. It is important that you dry it after cleaning for 5 hours before testing for tolerance. The choice of cleaning solution is important. If a volatile solvent is used (acetone, lacquer thinner, alcohol, etc.) the evaporation will chill the surface and distort it. So, it is necessary to allow the plate to return to normal temperature before using it to avoid measurement error. In case of water-based cleaner there will be some evaporative chilling. The plate will also retain the water, and this could cause rusting of metal parts which are in contact with the surface. Some cleaners will also leave a sticky
residue after they dry. This will attract airborne dust, and actually increase wear, rather than decrease it.A surface plate should be under constant temperature and with less than 50% relative humidity. Avoid direct sunlight or sudden draughts.

This is a supersurfacer. Supersurfacers are special machines, they are like a big handplane, they can take a single shaving of 0.001" thick from a board that is 12" wide ( some machines will dress up to 24" wide) Pretty remarkable!
Well this little puppy is a special supersurfacer, it dresses a face and an edge at ninety degrees!
So somebody in Japan spent a boat-load of money to build a machine to do high precision woodwork, even though wood moves.

Some people do accuracy in wood!

So don't believe all of those who don't and tell you, that you can't.

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[Bill Dufour]

The two towers of the Golden Gate Bridge are exactly vertical as determined by optical devices. But they are about six inches further apart at the top compared to the bottom. There is nothing wrong with their relative orientation.
Bill D

[Eric Schmid]

Joint one face and one edge, make a slightly oversized cut on the bandsaw, then plane the other two sides to dimension. If your jointer and planer are set up accurately, the resulting boards should be ready for cross cut and joinery or assembly depending on what you’re making.

I rarely check for square in the manner you describe except when setting up machines. If I do check, it’s the two reference surfaces created on the jointer.

So yeah, it’s probably square enough for me because I doubt I can hand feed through the jointer with that level of accuracy and do so consistently.

Any issues are resolved in final fitting and assembly, which are usually minor.

I don’t enjoy ripping solid lumber on the table saw either. I leave a crosscut blade on that tool and do all my ripping on the bandsaw, which is always set up for resaw and ripping.

[Mark Hennebury]

Vertical, as in reference to the center of the earth. Two vertical lines on the surface of the earth that were a distance apart will be further apart at the top and meet at the center of the earth. Two parallel lines would be the same distance at the top and bottom, but they both wont be vertical


The two towers of the Golden Gate Bridge are exactly vertical as determined by optical devices. But they are about six inches further apart at the top compared to the bottom. There is nothing wrong with their relative orientation.
Bill D

[Bill Dufour]

I have never seen woodworking measuring tools any where near the accuracy of those for metal. It just does not matter that much for wood since it moves so much. No woodworker I know of worries about body heat from their hands affecting measurement instruments, metal workers do. The claim is a jump of 1/1000 of an inch, on a flat surface, is visible to the human eye.
Bill D.

[Patrick Walsh]

I don’t know I’m somewhere in the middle on this well not really I’m all the way to the right of it absolutely matters. The wood moves argument only holds as much water as ones willingness and ability to mitigate and manage the factors that cause it to move. Same with square really. As mark suggested get your shop “machines” setup so they cut square then keep them that way and generally you should be building square stuff.

It comes down to this imop and in my own building regarding square and wood movement. Sure wood will move but generally I plan my builds as to process parts and assemble them in a timely enough manner that they don’t have to time to go out of flat or fall out of square. Well not all aspects of a project but the ones that matter. It tends to be that most matter to me.

Square on Theo edges of the jointer absolutely matters. Being able to repeat those two edges on a planer or however you do absalutely matters if you going to join something to both edges and or if both edges with reference something else where a gap needs to be non existent or square must be maintained.

The edd cuts on stile and rail stock for doors or frames absalutely matter in a metal like precision or you fight square doors and panels. Out of square end panels are a royal pain in the ass.

Out of square on a machine compounds itself. Out of square in the project compounds itself. How much it matters depends on the application and or how many times this out of squar is going to repeat in a project and in a line or independent from the other parts.

Everyone gets from here to there different. That’s cool. For me the frustration and aggravation of dealing with crap not fitting perfect day in and day out “then guessing why” and figuring some work around to fix it just is not worth the frustration. Much more easy to get the machines properly setup then take the care they stay that way.

Also much more easy to purchase high quality tools such as squares or know how to tune them “I don’t” so I spend on someone’s tools I trust then check them as mark suggested.

It’s all perspective really. For instance, I just painstakingly built the top portion to the case of a pipe organ. I went through unbelievable pains to make sure the tiers having tall stiles of sorts with almost not rails to hold them parallel to each other would be flat “like dead flat” as when you put this thing together and stand it up if they are not it will look like shit.

So that meant milling and building slow and using joinery that would assure it have the best chance at staying flat after built. So get this I haul all the crap from my shop to my employers shop “I’ve been working from home” during the pandemic. I make clear as I always do we need flat surfaces to store theses parts. I get the brush off on the phone so I know what’s coming “the same thing you get from any boss or guy that did not actually build the stuff” so I show up and he has me put all these parts stacked atop each other on a bench all overhanging unsupported non the same thickness all leaning tower like real I’ve to a pice of wood staying flat.

So that’s last week. Then yesterday I drop by the shop,to get more material. I’m on one side of the bench he is at the other, he has a scrap of plywood he wrote a measurement on, he tosses it across 12pm of bench at me and I miss. It’s crashed down onto the work I went to great lengths and unreal pains to make perfect. Like perfect perfect perfect. Not one bit of tearout anywhere. Every edge a perfect 1/16 round over finished with 320. Like ready for the spray booth perfect. Some people’s idea of good just and or good enough are just worlds apart.

And that’s fine I’m not saying one guy is better than the other. As you know everyone has a different opinion. Sometimes one guy is right many times nobody is.

I just make stuff and I like perfect, I also like to struggle as little as possible and stack as many card in my favor as possible as the universe will surely have it way with me and I’ll struggle regardless of my best preparation. That being said and that being enough for me to have to accept a few consesions In my work limiting them from the behind and along the way with maniac like attention seems reasonable. Again responsible for me..

[Brian Holcombe]

Wood moves across its cells, doesn’t change its length. So there are areas where .002” can matter and areas where it will not.

Woodworkers routinely work to very tight tolerances, they’re simply unaware of it.

On squareness, I prefer better than .002” over 3”.

Combo squares aren’t very square, I don’t care who made them. Some brands are better than others but they are a layout tool and not for checking squareness.

Checking for square is a task for a try square, typically and after it’s been verified.

Personally, I feel spending effort here saves considerable time later and generally makes a better product.

[Brian Holcombe]

Also, not sure where .005” machine shop tolerance comes from. It depends on the job, some jobs are not needing to be blueprint accurate, but rather they need to be repeatable. Other jobs, like interference fits, are at least one decimal place better.

Most shops will find a comfort zone in which they are not building things to toolroom tolerances but where they are not causing undue grief and headaches, that may be .0005” in some cases and .005” in others.

[Robert Hazelwood]

I had thought about using the planer to dimension the width, but the length of these pieces are so close to their finished length, any bit of snipe would be a big problem. I try to rely on hand tools when accuracy is paramount, like in small or delicate pieces. In reality, I could take a few plane shavings off these boards and probably dial them in closer to perfection. The parts I'm working on are for a workbench base, so I think the level of square is acceptable. It just annoys me when I triple check all my machines and end up with anything other than perfect. Like I said before though, it may just be the limitations of my tools.

You may want to see if you can dial out some snipe from the planer. For the most part on my humble DW734 snipe is very minimal, difficult to see or feel, and comes out with a pass or two with the smoothing plane (which I would be using on the surface anyways).

Another thing that occurred to me is to check that the planer is cutting parallel. A few thou out across the width could cause some squareness issues that you might be blaming on the TS. Although your theory about the TS blade deflection on a skim cut makes sense. What kind of blade? I would venture to guess that a full kerf dedicated rip blade would be least prone to deflecting like this.

[Dan McGonigle]

You may want to see if you can dial out some snipe from the planer. For the most part on my humble DW734 snipe is very minimal, difficult to see or feel, and comes out with a pass or two with the smoothing plane (which I would be using on the surface anyways).

Another thing that occurred to me is to check that the planer is cutting parallel. A few thou out across the width could cause some squareness issues that you might be blaming on the TS. Although your theory about the TS blade deflection on a skim cut makes sense. What kind of blade? I would venture to guess that a full kerf dedicated rip blade would be least prone to deflecting like this.


Maybe I’ll run a board through the planer and measure thickness on each side with a caliper, see if it’s tapering along width at all.

TS blade is a Freud Premier Fusion 40T. I have a Freud thin kerf rip blade but I don’t use it too often, although It’s the better blade for ripping thicker stuff. I’m using a Grizzly 2hp table saw, The accuracy of this saw is not as high as a high dollar PM or SS or something. I accept that because that’s just what’s financially doable for me.

Regarding the comment that combo squares commonly are not square - I do have a set of “engineers” squares, that I use for set up sometimes. These squares are “square” visually if testing then by drawing a line, flipping, and drawing another line. They’re also square if standing up back to back with my Starrett. Those are about the only way I can check them. I’m not validating the accuracy of these tools, I’m just saying that I’ve checked them to the best of my ability, which to some may not be accurately checking them at all.

[Dan McGonigle]

You may want to see if you can dial out some snipe from the planer. For the most part on my humble DW734 snipe is very minimal, difficult to see or feel, and comes out with a pass or two with the smoothing plane (which I would be using on the surface anyways).

Another thing that occurred to me is to check that the planer is cutting parallel. A few thou out across the width could cause some squareness issues that you might be blaming on the TS. Although your theory about the TS blade deflection on a skim cut makes sense. What kind of blade? I would venture to guess that a full kerf dedicated rip blade would be least prone to deflecting like this.

Forgot to mention. I also am using the DW 734, and I rarely get snipe, maybe because I also use lift slightly on the workpiece as it enters and exits the feed rollers. Seems like when I do get snipe, it’s random and unexpected.

[Mark Hennebury]

Woodworking and metalworking are different, the materials are different and so are the properties different. You have to work within the properties of each. Wood, metal and granite move under certain conditions. People that work with these materials understand this and work around it.
High end metrology labs are temperature and humidity controlled.
Metrology tools like micrometers have plastic heat shields.
My surface grinder requires coolant to keep the surface of stock from distorting.

Woodworking requires you adapting to the properties of the material also.
It's all a game of working within the needs of keeping the material in a stable state while you work.

All of the boards that I have ever glued up were handplaned to probably 0.001" maybe less. I never "measured" meaning I never used a tool to measure the "gap" I did however use a method to check the feel of the fit, and that method is a close to the same method that is used in tool and die shops for fitting parts, where they use a surface plate and ink and rub parts. My mortise and tenon joinery were also fitted by feel, probably to even tighter tolerances. The difference is in woodworking you don't have high tolerance specifications for joints, so each person does them to their own preference; some maybe okay working to 1/16th gap other push on chasing 0.001" or higher. You can fit woodworking by feel to very high tolerance, and you can also measure it and machine it to high tolerance. I also use digital calipers and micrometers and machine to my own specifications when appropriate.

The example of the supersurfacer is a good one. you have a knife that is over a foot long,( on some machines over two feet long) with a back-knife ( chipbreaker) set a few thou back from the cutting edge and you can take a shaving 0.001" thick, you have some serious fine setup on these machines, you simply cannot be a couple of thou out, it wont function. The back=knife setup is a micrometer jig.
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I have never seen woodworking measuring tools any where near the accuracy of those for metal. It just does not matter that much for wood since it moves so much. No woodworker I know of worries about body heat from their hands affecting measurement instruments, metal workers do. The claim is a jump of 1/1000 of an inch, on a flat surface, is visible to the human eye.
Bill D.

[Mark Hennebury]

You need 3 squares and a reference flat surface to verify squares.
Stand square #1 on the flat surface and check square #2 and #3 against it, if they fit perfectly together, that tells you that 2 &3 are both the same angle and that they are complimentary angle to #1, but not what the angles are.

Now check #2 and #3 against each other, if they fit perfectly, then all squares are 90.
If not you will see the error, and it will be half of the error between #2 and #3




Maybe I’ll run a board through the planer and measure thickness on each side with a caliper, see if it’s tapering along width at all.

TS blade is a Freud Premier Fusion 40T. I have a Freud thin kerf rip blade but I don’t use it too often, although It’s the better blade for ripping thicker stuff. I’m using a Grizzly 2hp table saw, The accuracy of this saw is not as high as a high dollar PM or SS or something. I accept that because that’s just what’s financially doable for me.

Regarding the comment that combo squares commonly are not square - I do have a set of “engineers” squares, that I use for set up sometimes. These squares are “square” visually if testing then by drawing a line, flipping, and drawing another line. They’re also square if standing up back to back with my Starrett. Those are about the only way I can check them. I’m not validating the accuracy of these tools, I’m just saying that I’ve checked them to the best of my ability, which to some may not be accurately checking them at all.

[John Sincerbeaux]

Are we talking woodworking here or lunar landings?
Accuracy usually degrades as any project develops. Nice “dialed-in” machinery and tooling is a desired start but it’s only the start. I’ve never in my life checked how square my squares are. I’ve never used a feeler gauge ever in woodworking. The most geeked out I get is in wood thickness, weather after final milling or joinery parts. For that I use a digital caliper.

[Mark Hennebury]

I don't agree with this idea at all.
Accuracy doesn't degrade if you have sound process and do good project management.
I have done lots of complex joinery that requires accuracy and precision within one or two thou.
When you have multiple parts fitting together you have to develop a system to check and reference every step to prevent accumulating errors, if you don't error will rapidly compound and prevent the job going together.

I also said that you don't need a ton of high end metrology equipment to be accurate, just need to understand how to check you setups.

The credit card holders i produced hundreds of these, so tolerances had to be held tight, a couple of thou off and they are trash.




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Are we talking woodworking here or lunar landings?
Accuracy usually degrades as any project develops. Nice “dialed-in” machinery and tooling is a desired start but it’s only the start. I’ve never in my life checked how square my squares are. I’ve never used a feeler gauge ever in woodworking. The most geeked out I get is in wood thickness, weather after final milling or joinery parts. For that I use a digital caliper.

[Brian Holcombe]

Life is easier with accurate equipment. I don't second guess my findings and that is valuable in and of itself.

[Brad Shipton]

I think at some of the figures being suggested one needs to consider the reality of their machine. I cannot produce parts nearly as accurate as a supersurfacer on my Hammer J/P, nor will my shaper produce the same results as a Martin. Why? Bearings, and the accuracy of the parts that are assembled to make the machines. I know Mark and Brian can measure this, but some of us cannot. I aim for the best I can with the setup tools/equipment I have, and am constantly improving as I learn from others. If it fits, and I happy, good day. I have to put down the 24" calipers many days.

[Kevin Jenness]

Without questioning the importance of accuracy and precision in general, let's go back to the original post. The parts in question are the horizontal elements of a bench base trestle which are going to be mortised to accept the legs. They have two parallel surfaces, one square edge and one that is slightly out of square, No matter what process is used for mortising the fourth edge can be ignored and a mortise square to the faces/ parallel to the good edge can be produced within the capabilities of the mortising equipment. So yes, the pieces are "square enough" for use.

[Bill Dufour]

I just finished getting the top on my tablesaw. I have the blade aligned parallel to the mitre slot within about .001" in the diameter of the blade Should I break out the .0005 DI and fight it down smaller? How much is too much as to be unsafe. It was within .01 just by luck at first.
Bil lD

[Robert Hazelwood]

I just finished getting the top on my tablesaw. I have the blade aligned parallel to the mitre slot within about .001" in the diameter of the blade Should I break out the .0005 DI and fight it down smaller? How much is to omuch as to be unsafe. It was within .01 just by luck at first.
Bil lD

I will defend working to thousandths, but ten thousandths are getting silly for woodworking :)

[Jim Becker]

I will defend working to thousandths, but ten thousandths are getting silly for woodworking :)

I will agree that there may be limited practical benefit based on the material being processed, but there's absolutely nothing wrong with someone dialing things in even more precise if they want to. There's zero negative to that other than time and, perhaps, a few bad words being uttered from time to time. :)

[Osvaldo Cristo]

For practical reasons in woodworking (I am an Engineer with microelectronics background so I am comfortable to work at very high precision) my smallest reliable measurement with my steel rules is 0.5 mm. I consider my squares "bull´s eye" precise if on 300 mm lenght I have 0.5 mm error or less. It means 0.1 degree error (1:600).

Your propose is equivament to 1:1,500 - thoughter than mine!

[Jared Sankovich]

The entire set is cheaper than a 12" woodpecker square, and inherently more accurate than a combination square.

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[Andrew Seemann]

Anyone else here remember the 1970s when the most accurate tool 90% of woodworkers owned was a Craftsman combo square and most had never heard of a thousandth?

I suppose you could say the same about 1770, when the the most accurate tool a professional woodworker owned was an ivory rule and no one had ever heard of a metal plane.

How ever did they get work done? :)

[Brian Holcombe]

That is a bit a strawman, given that if we’re using machinery it can very well be made accurate. I’m not sure who 90% of woodworkers refers to when you can clearly see very stout and precisely made machinery and measuring tools from US, Europe and Japan from that era and prior and presumably many professional woodworkers used those tools.

Finally, when one works by hand one uses hand method of fitting individual parts.

[Bill Dufour]

What I find very imprecise is when a woodworker will say my fence is out of parallel by 2/1000. But no mention of in what distance.
Reminds me when I complained to the city that there was hump in the gutter in front of my house. Some engineer type responded with a letter that it was within tolerance. Some thing like 6 inches in 1000 feet so they would not do any repair. I suppose the average slope was good but it humped up so there was a 2" deep lake in the gutter unless the sprinklers were off for a few weeks in summer.
I put a little oil on it every few weeks to kill mosquitos.
Bil lD

[Mark Hennebury]

I remember the 70's well, i have been woodworking since then. Most of my machines are from the 50's, Robinson and Wadkin, i do have a few more modern machines from the 70's, like Marunaka supersurfacers, Balestrini mortise and tenoners, Maka Mortisers (All designed and produced in the fifties and sixties.}

This is an old 70's machine that i rebuilt last year. Craftsman table.....oh no actually a Dinky little Martin table saw, and a mickey mouse jointer from Japan. Last photo has a little 20"Wadkin Jointer from the 50's, a hobby shop 30" Robinson Bandsaw from 1951, a Dean Smith and Grace lathe from 1959. a Wadkin LQ mill/ router type thing, from the 50's. I could go on for quite a while.

i think you need to broaden your horizons.
Woodworking is a wide world. Room for everyone. Lots to learn
Share what you know and how you do it.



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Anyone else here remember the 1970s when the most accurate tool 90% of woodworkers owned was a Craftsman combo square and most had never heard of a thousandth?

I suppose you could say the same about 1770, when the the most accurate tool a professional woodworker owned was an ivory rule and no one had ever heard of a metal plane.

How ever did they get work done? :)

[Ryan Yeaglin]

Standard unspecified machine shop tolerance is +/- .005" (A machine shop that sees an untoleranced diameter, without knowing the design intent, may apply a standard tolerance for three-decimal-place untoleranced dimensions, ±0.005 in). Not saying that there aren't tighter tolerances, just stating the standard.

[Ron Citerone]

I layout all of the boards that I am going to glue into a panel, put the cabinet makers triangle on them, and mark each edge of the joints alternately out/in. I go to the jointer and run each edge away from the fence or toward the fence. This cancels any error that my jointer fence is not exactly 90 degrees.


Yes, what Frank said!!

[Brian Holcombe]

Standard unspecified machine shop tolerance is +/- .005" (A machine shop that sees an untoleranced diameter, without knowing the design intent, may apply a standard tolerance for three-decimal-place untoleranced dimensions, ±0.005 in). Not saying that there aren't tighter tolerances, just stating the standard.

You can appreciate that length and size tolerances are much different than tolerances for squareness and parallelism.

It has been my experience that tenon shoulders being out by .002” over 3” or similar would show minor but visible gaps which would require some kind of filler. Completely different than a part size tolerance of .002”.

Not to say I’ve never made a gap, but the goal is basically to reduce them to zero.

Practically speaking that means the error must be smaller than the woods ability to crush under clamping pressure to disappear the gap. That can at times be fairly generous and with harder and lighter colored woods it can be quite small.

[Patrick Walsh]

Mark,

You just became my second hero of the day next to Howard Stern.

Go take a listen. Hopefully o don’t make a mortal enemy after you do but if I do so be it lol..

Oh and by the way that jointer!

And why Im on a roll you really do some crap work.....


I remember the 70's well, i have been woodworking since then. Most of my machines are from the 50's, Robinson and Wadkin, i do have a few more modern machines from the 70's, like Marunaka supersurfacers, Balestrini mortise and tenoners, Maka Mortisers (All designed and produced in the fifties and sixties.}

This is an old 70's machine that i rebuilt last year. Craftsman table.....oh no actually a Dinky little Martin table saw, and a mickey mouse jointer from Japan. Last photo has a little 20"Wadkin Jointer from the 50's, a hobby shop 30" Robinson Bandsaw from 1951, a Dean Smith and Grace lathe from 1959. a Wadkin LQ mill/ router type thing, from the 50's. I could go on for quite a while.

i think you need to broaden your horizons.
Woodworking is a wide world. Room for everyone. Lots to learn
Share what you know and how you do it.



433035433037433038

[Tom M King]

I think the name of that Japanese jointer is quite fitting, especially if pronounced in Southern American English.

[Patrick Walsh]

Didn’t even notice that. Now I just gotta have one mostly because such I’m such a crass wise sass punk. Or maybe I’m just CUNY like you..

How can I live without the opportunity to show everyone when the visit my shop my giant Fukami. Of course if someone was gonna have a giant Fukumi in theirs shop it would be me..

Fu
I think the name of that Japanese jointer is quite fitting, especially if pronounced in Southern American English.

[Mark Hennebury]

Oh and while i am at it; back in the old days before "Craftsman combo squares" The Inca seemed to take precision seriously. So apparently it;s not a new thing. 433043

Some people get it and some don't, i guess.

[Mark Hennebury]

Hi Patrick.

Always glad to hear from you.

I will check out Howard.




Mark,

You just became my second hero of the day next to Howard Stern.

Go take a listen. Hopefully o don’t make a mortal enemy after you do but if I do so be it lol..

Oh and by the way that jointer!

And why Im on a roll you really do some crap work.....

[Patrick Walsh]

Wait aren’t we talking about squares.

So why are you posting pictures of rock, not one of such to be square. You would use a square for that work lol..

And aren’t the Inca like some tribe in Mexico.

Oh crap here I go again...


Oh and while i am at it; back in the old days before "Craftsman combo squares" The Inca seemed to take precision seriously. So apparently it;s not a new thing. 433043

Some people get it and some don't, i guess.

[Zac wingert]

This thread went sideways. But for me, square enough is if you are pleased with the job you did. Worrying about thousandths just for the sake of it is silly. If you joints don’t have gaps and the work looks good, who cares? And to answer the initial question, yes that would be acceptable. If your striving for further perfection, work with metal, wood moves anyway.

[Zac wingert]

I guess I should clarify. No one is gonna critique your work for something out of square or out of line if the naked eye can’t see it. Do you imagine guest to your house will judge you that your dining table is 0.002 out of line? How would they even know? Feeler gauges and dinner? Hah! So take it for what it is. At the same time, i realize this is a work bench, not a dining table, but you will dent it if any work is done on it, it’ll get humid and dry with seasons and affect for change than that. if you want to strive for perfection, there is nothing wrong with that. But it’s it absolutely necessary for every single project? Of course not.

[Andrew Seemann]

Actually, metal has an annoying habit of moving too:) At one of the shops I worked at, the foreman would freak out if someone left the good 24" B&S square in the sun. But yes, these threads about precision tend to go down the rabbit hole fast. And that is from a former machinist (and woodworker who uses calipers and a dial indicator to set up tenon jigs).

If the original poster is still reading this thread, assuming your square is in good condition, yes, the out of square is probably caused by the cutting load being on one side of the blade. For thinner wood it usually isn't an issue, but with a blade sticking up 2 or 3 inches, even with a softer wood like poplar, you can get some deflection. I normally try to rip with at least an eighth on the waste side when I can. Rotating the piece the same direction can compound the error.

As for 0.002" out of square across 3 inches, there aren't many things in woodworking that would require that level of accuracy. I would say a workbench leg isn't one of them.

[David Buchhauser]

Actually, metal has an annoying habit of moving too:) At one of the shops I worked at, the foreman would freak out if someone left the good 24" B&S square in the sun. But yes, these threads about precision tend to go down the rabbit hole fast. And that is from a former machinist (and woodworker who uses calipers and a dial indicator so set up tenon jigs).

If the original poster is still reading this thread, assuming your square is in good condition, yes, the out of square is probably caused by the cutting load being on one side of the blade. For thinner wood it usually isn't an issue, but with a blade sticking up 2 or 3 inches, even with a softer wood like poplar, you can get some deflection. I normally try to rip with at least an eighth on the waste side when I can. Rotating the piece the same direction can compound the error.

As for 0.002" out of square across 3 inches, there aren't many things in woodworking that would require that level of accuracy. I would say a workbench leg isn't one of them.


Agreed - 100%.

[Mark Hennebury]

Original question: "Bottom line. 0.002” over 3”. Is that square enough for you?"

Simple Answer: Yes...No... Maybe...depends.


The reason the thread goes sideways is that people make statements that offer their opinions as if they are facts, then they get blow-back.

If you answer, yes that's plenty good enough for me, or no I like to do better, Or it depends on the application etc..you wont get any arguments.

The arguments start when people make statements about what, others can and cannot do, based on their own limitations, or lack of knowledge.

When people make statements about the limits of machinery, joinery, measuring and marking and fitting of wood, that are incorrect, they will get arguments from those of us that know different.

[Bill Dufour]

Quality micrometers have rubber grips on the frame. It is not for comfort. It is a feature.
My answer is , as much as possible, inset one piece from the other at least 1/8 inch. that way a few thousandths does not show. My tables or chairs the apron is not flush it sits back a fraction from the legs etc. Frame and panel construction ignores this as well. This is the reason for raised panels and beveled glass. Just take the edge down close enough to fit and let the field be a little off.
Bill D

[Dan McGonigle]

I'm glad everyone has enjoyed the this thread, sideways or not. For anyone still interested - Last night I milled the vertical leg members for this bench base, and used my planer to dimension width - results were more accurate than my tablesaw, so thanks for all those who suggested such.

I truly appreciate the tight tolerances of "fine woodworking" and I strive to be as accurate as possible. But I guess that's the challenge and learning curve of woodworking, for me at least. My first woodworking projects were using home depot pine boards and dowels. Downright embarrassing compared to the pieces I've built in the years following. I'm an amateur, no doubt. But questioning 0.002" over 3" is what helps me grow as a woodworker. For the current project, I think I'm happy with the level of accuracy.

I agree with Zac that worrying about 0.002" just for the sake of it not being 0.001" or better is useless. It's sometimes hard for me to fine the area in between "good enough" and "it could, theoretically, be better".

But reading through this thread and having some of you validate the fact that these measurements will not ultimately affect the function of the bench, I'm happy with it. Next time maybe it'll be tighter though. We'll see.

[Brian Holcombe]

That is a good outlook! For me, this is part intellectual pursuit, so finding out why and improving is part of the enjoyment. Each project completed gives me a chance to review what I could be doing better.

I used to work for a place that sold danish furniture, one brand we sold manufactured furniture designed by Carl Hansen. I was probably 7-8 years into woodworking at the time and upon inspecting one of Wegner’s chairs with a woodworkers eye, I could not find a defect. Perfect wood, perfect finishing, perfect joinery, tight laminations and high quality design which utilized compound splays to make a sound structure, worst of all it was affordably priced.

I went home and realized that at the time I could accomplish none of those things to the same level of quality. At that point I decided I better start making improvements.

[Derek Cohen]

That is a good outlook! For me, this is part intellectual pursuit, so finding out why and improving is part of the enjoyment. Each project completed gives me a chance to review what I could be doing better.

I used to work for a place that sold danish furniture, one brand we sold manufactured furniture designed by Carl Hansen. I was probably 7-8 years into woodworking at the time and upon inspecting one of Wegner’s chairs with a woodworkers eye, I could not find a defect. Perfect wood, perfect finishing, perfect joinery, tight laminations and high quality design which utilized compound splays to make a sound structure, worst of all it was affordably priced.

I went home and realized that at the time I could accomplish none of those things to the same level of quality. At that point I decided I better start making improvements.

Brian, you recall that I made a damn close copy of Wegner's "The Chair" using just hand tools for all the joinery and shaping (only a bandsaw for roughing out). The end result looks identical to the non-woodworking eye. For some reason those who see them together (as I have an original The Chair at home) prefer my version. I suspect it is all the irregularities and (hopefully) minor :) errors that contribute to ... let's call it .. warmth. But the absolute tautness of the factory-made joinery and parts is amazing. At the time of the build I found, viewed and shared many of the videos made at the factory. They used copy lathes for many years. I guess that they now CNC everything. And it is eye-opening to know that Hans built every prototype with hand tools!

Which is which? :)

http://www.inthewoodshop.com/Furniture/WeavingSeatCompletingTheChair_html_m1a3cedf0.jpg

For the lighter side of accuracy, I am always grounded by this now classic from Chris Wong, The Magic Square ....


https://www.youtube.com/watch?v=dB0MBGiX8TQ

Regards from Perth

Derek

[Brian Holcombe]

Cnc in and of itself does not make a perfect product, it helps but it alone doesn’t do it. In fact factory furniture is not all perfect either, they can just as well build the same error in every time.

It still requires a commitment to making those errors as small as possible.

[Jim Becker]

Precision joinery and more random surface finish go hand in hand with craftsmanship. The former can be done with any tool methodology that works for, is prefered by and is available to a given woodworker. The latter is all about "finesse". Combine that with really careful material selection and the end result is "wow".

[Eric Arnsdorff]

I'm going to buy a magic square. Or make one.
I just hope I can achieve the required precision!
Or is that accuracy?
Maybe it's uncertainty...

[Bill Carey]

............ For the lighter side of accuracy, I am always grounded by this now classic from Chris Wong, The Magic Square ....

Regards from Perth

Derek

Thanks for posting that Derek - had never seen it. Started my day with a chuckle and , I think, the proper perspective.