How Accurate is Your Work / Project?

When I took shop class all thru high school, when ever a student was off on a project and would argue with Mr. T that it was "good enough>>>"  Mr.T would say in his perfect English, "There ain't no such a thing as gudenuff.  Its gotta be purfic".  Eventually, I was introduced to the building trades.  That was in 1949 and new construction was really revving up.  My first contractors were more into remodeling houses that had been built well before WWII, some even as old as Pre Revolution.  A lot of those old houses were neither level or plumb.  With some additions, it was possible to do the add ons with precision, as there would be no way that the sight could tell if the new lined up with the old.  In other instances, an add on might include an individual exstention of a large room being made even bigger.  I learned how to "eyeball" so that there would be no discrepancy between old to new.  I learned how to lay out so lines were straight, altho not necessarily level or plumb.  Level and plumb were made up in other parts of the construction, or with shimming or cambering of parts of the framing.

I realized very soon in my experience that there were many "ways to skin a cat," as the old saying went.  I knew I would be going into the army very soon, so I made up my mind to learn as many ways as possible.  When looking for a job, i learned very quickly that the first question i was always asked was, "How do you stand with the draft."  I answered that i was 1A and would be going as soon as I finished my 2 years of college.  I did not want a steady job for more than three months and i would be gone soon there after.  I stuck with that answer thru several interviews.  At end of three months, i always moved on to a new contractor.  Each contractor had different methods to arrive at same end result.  I never argued about how so and so did it differently, but tried to learn the "new" method as best I could.

The result of that philosophy was that I learned a lot more than had i worked with only one contractor.  i learned how to pitch in right away with my eyes wide open and show that i was receptive to any new methods.  AND, I worked like hell.  By the time i had been working for a few months around the trades (i worked mostly with contractors who did everything "in house") I was becoming known well enough that I was often approached to work long befoe my three months self imposed restriction was done.  Eventually, when i had come home from military, i was called by several builders within the first two days after i came home.  Most of those builders were the ones who i had worked on those old houses where we had to change from eye balling to exacting all on the same job. Since high school (actually since i was a 9 or 10 year old on the farm), i have never been out of work unless i wanted to be.  With carpentry, it was always as close as I could get with a folding rule, a square, level and straightedge.  With plumbing, well it was actually a little closer that what I had always heard about "Who cares.  if it is under pressure, it doesn't matter which way a pipe runs.  If it's waste, it just needs to run down hill"  I did work hard to be a tad more accurate than that.  With masonry.  A lot of my work was done by eye.  Get the starting courses exact as far as level/plumb and square.  the rest of the way only took a few checks the rest of the way.  With rough stone work, (as opposed to cut stone), it often came down to "how does it look?"

Now, i am learning about finished woodworking and the measurements do need to be fine tuned a little better.  I am still learning. Heck, i am only 39 so i have a lot of time to make improvements.
Tinker

 
As I'm sure you realize Peter it all depends on the project. I guarantee I did not use a micrometer when rebuilding a section of fence about a month ago. But my posts are within about +/- 1/16" of the string line. But that isn't gonna do when I get busy making box joints. If you haven't seen this vid it illustrates the benefits of being extremely precise
 
Jason Kehl said:
On foundation work we square and level the forms to 1/16" before pouring concrete. After pouring the concrete we accept about 1/8" or so on average over the foundation, there always some slight undualations with concrete.

When framing we work to the 1/16.

For interior finish everything must be tight and crisp looking with no visible gaps. Exterior finish we shoot for the same quality but will accept small spaces, less than 1/16", unless it is an area that will be caulked for weather proofing then 1/8" is easily filled with caulk and often speced by manufacturers anyway.

Cabinetry is tight, feels smooth and looks pretty.

j

1/16" on framing, eh?  That kind of accuracy is unheard of in framing around here. Too often I see walls that are framed over an inch out of design spec, with corners nowhere near 90°, and what's appalling is that this shoddy workmanship is acceptable to some local builders.  As noted by others, wood does move over time, but to start with a build that far out of spec just exacerbates the condition when the wood moves. 

Many years ago I was in a crew building a house.  A colleague and I had built a 32' wall and were about to stand it up when the owner heard us arguing about the final dimension and came over to see what the issue was.  I commented that I thought the wall was 1/8" out and my colleague had said it was right on.  The owner said, "1/8 inch in 32 feet?  Jayzus!!!  Put the danged thing up!!!" 

I will use much tighter accuracy in setting up machines to do the work, but if I can get things together within 0.5mm when working with wood, I'm delighted.  I don't bother with feeler gauges when it comes to wood. 

 
I have a reputation as being extremely meticulous in my fine finish carpentry work and now my furniture building.

Measuring in 1/32's or even 1/64's is the norm.

For some joinery, I will even use machinist calipers to measure in thousandths.

There's no liquid trim allowed in stain grade.

 
>>>Many years ago I was in a crew building a house.  A colleague and I had built a 32' wall and were about to stand it up when the owner heard us arguing about the final dimension and came over to see what the issue was.  I commented that I thought the wall was 1/8" out and my colleague had said it was right on.  The owner said, "1/8 inch in 32 feet?  Jayzus!!!  Put the danged thing up!!!" 
 
You guys are way too fussy,  :-\, I do commercial aluminum store fronts and we had a job remodel on a grocery store where I had to cut 3/4" off the lock side of a 42" aluminum door because the floor was out that much.  The contractor wanted to know how I was going to weatherstrip the gap and I told him it wasn't my problem.  Another job, different contractor the vestibule sills for the sidelites and glazing had as much as 3/4" gaps all over the vestibule and again the GC wanted us to caulk...same reply.  It still amazes me how poor the craftsmanship can be on commercial jobs and still accepted by owners.  The most important thing the majority of times is finishing on the unrealistic time frames set.  My father always said "if you don't have time to do the job right today, how the H*** are you going to find the time tomorrow to come back and fix it".
 
For final planing I do have a Wixey digital gauge installed on my Dewalt planer and find that it gives me more confidence that it's really close to the desired thickness. Plus, I try to sneak up on the final thickness and use a digital caliper to double check before I do the final pass. (I said sometimes I go overboard.)

I sometimes use a digital caliper to verify width less than 6", but not always.

The other place I have gone digital is with a height gauge for saw blade height (now that I again have a table saw) and router bit height. I don't know how much more accurate it is than other methods but it gives me more conficence.

Other than that I try to fit the pieces together and make final adjustment cuts as I bring the whole project together. I have a Woodpecker's Story Stick Pro that works well for getting a piece to just the right length or width. And I've started to use more hand tools like planes and chisels to get a final fit.

I did think digital was the answer to everything awhile back, but have found it has it's place.

Accuracy and fit is all relative. Are Festools like the TS55, MFT, Domino perfect. No, I don't think so, but they do allow me to be more accurate than I was before. I bought an Incra router table/fence system recently because I feel it allows me to be accurate without really thinking about it. The positioner gives me a little edge in that direction.

When people start talking about accuracy to less than 1/64", that is beyond my understanding when cutting and assembling wood. I guess I strive to be as accurate as possible, but my aging eyesight and the limitations of being human essentially limit my level of accuracy to one which satisfies me in the sense the project goes togther and looks the way it was intended to.
 
Generally for the carpeting I do in and around the house a 1 mm precision is good enough. Sometimes I eyeball it on the half millimeter, but I never need anything more precise. 
 
Peter Halle said:
There has been recently a flood of posts referring to the use of feeler gauges and digital calipers for determining the accuracy of work.

Peter

I haven't seen anything about using those tools for 'determining the accuracy of work'  What I did see was people using those tools to determine the accuracy/precision of their Festools

Life is full of choices.  Some people are OK with driving a Hyundai, some people feel like they need a 200 mph Ferrari.  Are they ever going to go 200 mph - probably not.  But the fact that it can do it is part of the allure...

Now apparently some people who have purchased very expensive Festools (that often cost two or three times the price of other tools) decided to see if they could actually do 200 mph (so to speak) - and that is where the feeler gauges and dial calipers come in to play.

They are finding out that 'reality' does not meet their expectation of precision/quality...  The common answer to that is - cut a board and see how it does, etc.  But your missing the point
 
[size=14pt]But John, some [to continue your analogy] have
checked the manufacturing tolerances and clearances on the Ferrari Motor, before they even started it.  [smile]

John H said:
Peter Halle said:
There has been recently a flood of posts referring to the use of feeler gauges and digital calipers for determining the accuracy of work.

Peter

I haven't seen anything about using those tools for 'determining the accuracy of work'  What I did see was people using those tools to determine the accuracy/precision of their Festools

Life is full of choices.  Some people are OK with driving a Hyundai, some people feel like they need a 200 mph Ferrari.  Are they ever going to go 200 mph - probably not.  But the fact that it can do it is part of the allure...

Now apparently some people who have purchased very expensive Festools (that often cost two or three times the price of other tools) decided to see if they could actually do 200 mph (so to speak) - and that is where the feeler gauges and dial calipers come in to play.

They are finding out that 'reality' does not meet their expectation of precision/quality...  The common answer to that is - cut a board and see how it does, etc.  But your missing the point
 
Precision is not as much a destination as it is a quest. In metal machining most jobs come with a tolerance required. In woodworking and carpentry there are no specified tolerances in most cases, I've never seen any on any of the jobs I've worked on so everyone has to set their own degree of precision. My family has a curse so the first couple houses we built we spent a lot of time recutting boards because we tried to get them too precise. When I started working for contractors I found out you can't measure twice and cut once on everything or you will take twice as long to get it done. You will make a mistake once in a while but overall you have to proceed with confidence and then just correct those things that are wrong. I think understanding the real need vs perceived need for precision is the key to doing anything well. I also believe procedures are extremely important in arriving at a fine job. Which is more important, that each cabinet be precise to .001 or that they are all very close and they fit in the space required. Stacking tolerances can be a big problem in cabinets, even small numbers add up if you have a big run so it's the total length not any individual cabinet that's important. When I install cabinets in a house where the floor isn't level and the walls are not plumb do you think anyone cares that the cabinets are not + or - 1/128. Learning how to set up for these problems  and fix them is more important  than maintaining unreasonable tolerances.  Working to make a living and woking  as a hobby is so different, one just wants a good job the other needs a good job in a time frame that makes money. In the professional world much of this is related to where you're located. Different areas have different expectations, in my county they want you to work for $10 an hr and they expect something a little better than the farmer down the road could do. I don't work here much. The larger cities are better but only when working for individuals, I won't try to work for the contractors around here, they want cheap and fast. I have only recently started using a caliper in my work and not often. 
 
Peter Halle said:
There has been recently a flood of posts referring to the use of feeler gauges and digital calipers for determining the accuracy of work.

I know for a fact that since 1983 I haven't used a feeler gauge for anything other than an automotive situation.  Am I behind the times?  Has wood movement changed to be more stable in the past 30 years?  Am I behind in the times and also techniques?

So my question to all is:  What is the degree of accuracy you expect in your projects?

I've used feeler gauges to setup machinery (i.e. jointer).  I buy equipment that stays "in tune" for a long period of time, so I prefer to set them up as precise as possible.  In some cases it pays off, others probably not necessary.  If I want the ability for very precise setups, it's there.

For finer furniture work, I employ two methods to get things to fit properly.  I do use calipers and/or accurate setup blocks to get things as tight as possible.  If I am making multiples I find this can save a lot of time.  Otherwise, I will fit parts using hand tools that take fine shavings.

To me, most important is square and "the same" (meaning multiple parts match each other, not some exact measurement).  I try not to measure if possible.  I'd rather use a story stick, stop block, or some other method, but sometimes you just have to measure.  Very occasionally, that measurement has to be pretty darn accurate.

I do find the digital caliper helps me hone in on things like half-laps a little quicker than eyeball/test.  Machine setup like that is typically where I'll use them.  If you get the setup very accurate on a half lap, it takes very little sanding/planning/scraping later in the project.  A couple minutes of accurate setup can save some time on the back end.  A digital caliper is not required, just works faster for me in some cases.  Getting the dado blade width right is another significant example.  It takes two tries, get close, measure, measure shims, install, done.  Much easier to deal in digital thousandths than fractions or try/retry.  It's usually right on the very first test cut.  Does it have to be that accurate ... no ... but it's right on the first test cut. I got to the uber accuracy quicker than less accurate methods, so why not.

For the most part, a good combo square is all I need/use otherwise.

It should be noted that I don't do this for a living.  I strive to be efficient to make the most of the limited time I have.  I would probably be considered slow by tradesman standards though.
 
I've done very little contract cabinet building, but it has come up as part of a business I used to own building out recording studios. Racks couldn't always be bought that matched the design, we've done work where the owner wanted the surfaces flat to where a marble wouldn't roll despite the state of the walls/floors...

That said... I agree that it depends a lot on looks and feel. If you can see the imperfection in a place and way that matters... then it matters. Else, why would moulding be coped? Or why are some contractors so thrilled with their (over) use of caulk? Or why is it often customary to creep up on a cut with a chisel? Or folks using playing cards or business cards to do the same with a saw?

 
Related to accuracy, a good friend was buying a new development home in AZ and as part of his sales contract he demanded the builder meet their own QC specs and got a complete copy. IIRC walls were supposed to be no more than 1/4" out of plumb over 10', but when complete there were many walls 1/2"-1" out of plumb. At the price he was paying he expected better and got a full refund of his deposit and out of the sale. He ended up being very glad since it was just months before the RE crash. He went back a few years later, same house still vacant and a bunch of vacant lots. I bet that builder was wishing right then his work wasn't so sloppy.
 
I want to go back top the ferrari example.  How often does a ferrari go to the mechanic?  My very limited understanding is that these cars are tempermental and need frequent service.  Besides, I'm not positive that a ferrari is a fair comparison to FESTOOL.  Is a ferrari even close to as good of a car as festool's track saw is to track saws?  Who's qualified to say which is a better more precise manufacturer?  Festool is "tools for the toughest demands" and marketed as "best in class".  I've never read anywhere that Festool promises perfection.  I know that after I've taken the time to properly set up my new tool (most of my older tools don't offer fine tuning) the accuracy, speed at which I achieve that accuracy, cleanliness of work, productivity and quality of workmanship have increased.  Since I use my tools so much I've found many "options" that aren't even listed as selling points.  Many of the tools I have from Festool do a bunch of operations that they probably weren't even engineered to do.  I feel the sizeable investment I've made is worth it.  I hope you do to, and if you don't...thank goodness for the 30 day return policy.
 
[member=44695]djb[/member] Thanks for posting that video - John Economaki has had a big influence on 'tools that inspire quality' and precision is central to quality.  I had forgotten about that video, but having known John for 20+ years, it's true to his personal brand and philosophy.

Raising your game is partly about skill but also about tools that help you raise your game. 

BCTW and Festool are in the same league there.  Both have similar customer support and positioning mindsets - target the high end of the market with great support and tools that enable craftspeople to do their best work. 

BCTW says 'quality is contagious' and Festool says 'faster, smarter, better' - 

Both are about more precision and that builds confidence in your work.  Design matters more than cost to both organizations.  I can understand customers being upset when the reality does not meet that positioning.  Thankfully, Festool has a service organization, culture, and set of policies that really do support that brand promise.

 
I think the emphasis from Peter's question is how accurate is "your work" and not meant to be a criticism of other's accuracy needs.  I don't need a foundation framer (for example) to tell me how accurate I need tools to build fine furniture and I won't assume to tell him what he needs to do his job.

I think people need to read what people are saying before trying to come up with analogies (like the Ferrari) to explain why they don't need a specific tool to do their specific job.

We all need the right tool for the work we are trying to accomplish and while a less precise tool will still do the job, it just takes more time or skill to do that job.

I try to buy the best most accurate (within reason) tool to do the job I want it to do and I will comment when a given tool doesn't live up to advertised quality.  So far I haven't had a problem with Festool but, if I do I will say so and I don't pay attention to criticism from people that are skilled in a different occupation if they don't understand my reasons.

Keep up the good discussion but, try to reward and understand what others are commenting on before replying.

Jack
 
If you need to use feeler gauges for either the tools used or the material then you are in the wrong occupation.
Wood behaves differently to metal or plastic because it re-acts to moisture too and, for the sake of pedantic argument, only in two dimensions.
I do like to work as accurately as I can, I think it shows in my work and I get a subtle kick out of knowing it is. However, I will not get too prissy if something is 1mm or 0.something of a degree out from the design dimensions. I was taught " if it looks right, it probably is" .
There are roof structures that are hundreds of years old, cut by handsaw, that still do the job as intended prior to these new inventions of "uber" accuracy. Modern kit just makes life easier.

Rob
 
Rob-GB said:
If you need to use feeler gauges for either the tools used or the material then you are in the wrong occupation.
Wood behaves differently to metal or plastic because it re-acts to moisture too and, for the sake of pedantic argument, only in two dimensions.
I do like to work as accurately as I can, I think it shows in my work and I get a subtle kick out of knowing it is. However, I will not get too prissy if something is 1mm or 0.something of a degree out from the design dimensions. I was taught " if it looks right, it probably is" .
There are roof structures that are hundreds of years old, cut by handsaw, that still do the job as intended prior to these new inventions of "uber" accuracy. Modern kit just makes life easier.

Rob

I wouldn't agree that a roof structure and a piece of furniture or a cabinet are the same thing. However, I don't disagree with you overall. Obviously there has to be some degree of accuracy in building a cabinet or piece of furniture, but I find that getting the basic dimensions close is the most important and then the rest has to just fit together and within that structure. It's hard to just create from a cut list as there is always some degree of inaccuracy in all cuts with all tools. I like the "thought" of setting up my machines with an accurate tool or getting wood to a usable dimension with an accurate measuring device, but I don't really worry about "perfect" for anything because there is no "perfect". All work is limited by a person's sight, lighting, and just inherent accuracies or inaccuracies in all machines and devices. I have my share of digital, Woodpecker, and Incra measuring devices and tools, but I'm sure they aren't perfect either.
 
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