Any steel rules with graduations in 128ths?

[Cheese]

Here are a couple of photos Chuck, you can see how small the graduations become.
The scales are from top to bottom:
6" with 1/32" & 1/64" markings on reverse.
12" with 1/32" & 1/64" markings on reverse.
300 mm with 1/2 mm & 1 mm markings on reverse.
150 mm with 1/2 mm & 1 mm markings on reverse.

Just a note in passing, when working with the scales, make sure you grab the correct one because the metric scales are actually metric in overall length.

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[ChuckM]

I didn't expect that graduations in 1/128" were technically challenging to etch or mark, or visually difficult to read (my eye sights were considered just normal for my age in my last eye test) until I read all of your replies.  When I look at my 1/64" rule, I see a lot of empty space between each two marks with my naked eye, and so I thought there should be enough room to put a center line there.

1/100 graduations are clearly manageable for me based on Cheese's photos and the one I found on Amazon, and they seem to offer better refinements than 1/64".

Using a knife and a 0.3mm lead, guided by my 1/64"ths rule and a precision square, I produced a poor version of lines in 1/128ths (my zoom lens is nowhere near professional quality):

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For the question about what use I would have of a finely graduated rule in my work. I'll get back on that later after I have had a chance to take a photo or two today (or tomorrow).

 

[Cheese]

For accurately measuring very small items or flat items that don't lend themselves for use with a caliper, I've used this magnifying comparator for years. It really is quite handy. It's a 6X magnifier with 70 interchangeable reticles available. The reticles are sold as a pair, one with white markings and the other with black markings.

Shown here are reticles that measure in .005" increments and .1 mm increments. I also have a reticle that reads in .002" increments.  [cool]
https://www.finescalecompany.com/our-products

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[Packard]

Note:  If word-count adds gravitas to an argument, then this long post should be persuasive.  [eek] [big grin]

Those work for small items.  But for larger dimensions they would be useless.

There are a couple of things that are generally recognized about the capabilities of the human eye.

While we cannot judge the absolute color of an item accurately, we can match identical colors with great accuracy.  The reason being that our minds compensate for different color temperatures of light sources and “assign” in our minds what is the “correct” color.  That is why a blue napkin still looks “blue” when viewed under the decidedly yellow/orange of incandescent lights.

But matching colors is a strong suit of human sight.

The second thing we do with great accuracy is match sized.  We are not particularly adept at judging if marble is 3/4” in diameter or 7/8” in diameter, but place them close together we can see that they are not same sized.

That comes to be an advantage when measuring items. We can see with great dependability  that two machined blocks standing side by side on a granite surface plate differ in size by as little as 0.003” - to 0.005” depending on the individual.

It is the flatness of the granite block that allows us to do that.  It provides absolute alignment on one surface.  Without that absolute alignment we would be lost.

Vernier calipers and micrometers provide one absolute surface (the anvil end) and one measuring surface (the movable jaw).

But with a ruler, how do you provide that absolute?  Align it by feel?  I think so.  But that limits the accuracy potential.

While I think a careful operator could work to 1/64” with no difficulty, I think that getting perfect alignment at the “0” point and at the end point will be hit or miss.  And how do you transpose that dimension?  What kind of marking tool? A razor blade?

Our tool room worked to +/- 0.003” when required using machinery designed to work to those tolerances. 

They also made wooden jigs on that kind of equipment in about three times the amount of time it would take to make in my wood shop.

In other words, use the best tool for the task.

 

[ChuckM]

For those of you who consider a rule in 1/64" graduations sufficient, good for you. Here's an illustrative example where a 1/100th scale (since a rule in 1/128ths doesn't exist) would be more helpful for me:

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To cut a piece exactly the size of the opening, I can use a story stick, and set the table saw fence accordingly, but if there is already a rule that has a finer scale that works, why not just use the rule? I do a lot of setting the fence based on a tape measure, and I'm hoping to get a rule (probably 12" long) for that purpose.

Story sticks are not fool-proof. For example, making the tick mark itself may not be always accurate, and aligning the tick mark with the blade can also introduce a degree of imprecision.

 

[kevinculle]

When you are trying to get a perfect fit in a woodworking assembly a rule isn't necessarily the best tool.  If I were trying to fit that opening, I would take a measurement and set the stop on my Kapex for a +1/32" fit.  I would cut the piece to that stop and then place it in the assembly and measure the fit with a dial caliper.  Then I would use a set of shims between the stop and the workpiece to move it by the caliper measured offset and hold it down at that position with the hold down clamp.  I would reset the stop, cut the piece and cut more if it were a run of parts.

 

[ChuckM]

Snip.
If I were trying to fit that opening, I would take a measurement and set the stop on my Kapex for a +1/32" fit. Snip.

That is exactly a process I try to avoid in my day-to-day routine. I aim for doing it right the first time, rather than by way of trial and error. Of course, if a large quantity is involved, I do test cuts before the mass production. If I fail in a particular cut, I have hand tools including a shooting board that often can take care of the fix needed.

I'm not sure if a finer ruler will make things quicker or better, but I'll get a 1/100th ruler to find out.

 

[rvieceli]

Let’s assume for a moment in your example, the 1 and 19/64 measurement isn’t good enough. Although I can’t understand why it wouldn’t.

I’m with Kevin, I think you need a caliper. Although my method might be different.

If you think a 12 inch rule is adequate then you can use a 12 inch caliper or a 6 inch and 2 1-2-3 blocks. Use the caliper to measure the inside dimensions and transfer to your saw

Another option is to not measure at all. In reality you don’t really need to know the exact dimensions you just need the part to fit.

In your example take a double square and place the head inside space adjust the blade until it just kisses the other side lock it and then transfer to your saw

Use two pinch sticks. Two sticks and a binder clip. Spam the space lock the sticks in place with the binder clip and transfer to the saw

In every method remember to take the saw tooth into account when transferring if it’s wider the the blade.

Ron

 

[kevinculle]

I aim for doing it right the first time, rather than by way of trial and error.

That's always preferred but I haven't yet found a tool that will make a part cut a bit too short longer.

 

[rmwarren]

I aim for doing it right the first time, rather than by way of trial and error.

That's always preferred but I haven't yet found a tool that will make a part cut a bit too short longer.

[popcorn]

 

[ChuckM]

[popcorn]

It's through exchanging methods of work, however diverse or different that they may be, that we get to expand our horizon or skillset.  [big grin]

 

[Cheese]

In my money-is-no-object world, there is nothing better than to spend tons of money on precision measuring tools and precision cutting equipment...hey you can't take it with you.  [big grin]

However in my practical world, I will demure to Kevin's position and I'm really a fan of the shim process. Clever...very clever, I will use that in the future.

However, while that gets me very, very, close, it still doesn't get me an exact fit. For that I need to use the shim process mentioned to get me close AND then the "putting side pressure" on the Kapex blade to shave off a couple of thousandths.
A little bit of side pressure will give .001"-.003", while a lot of side pressure will give me .005" or more.

It's really all trial & error, and while measuring a distance is relatively easy and very important, producing that same distance in a product, on a repetitive basis, is practically impossible unless you're machining it with a machine tool designed for metal fabrication.

 

[rmwarren]

I can't measure/mark/cut and consistently get within.5mm to save my life. Where this poses problems for me is mostly working with metal for jiggie type stuff.

Lately I'm relying on gauges of some type (gauge blocks, story sticks, etc.) instead of rulers and if necessary sneaking up on the final dimension.

RMW

 

[Cheese]

I can't measure/mark/cut and consistently get within.5mm to save my life. Where this poses problems for me is mostly working with metal for jiggie type stuff.

Lately I'm relying on gauges of some type (gauge blocks, story sticks, etc.) instead of rulers and if necessary sneaking up on the final dimension.

RMW

Ya I'm all in on this Richard...in my world there is nothing more positive, accurate & repeatable than a hard stop, thus the reason I'm in full support of Kevin's earlier suggestion.

It all depends upon what your needs are, I can easily hold .001" on metal and can hold .015" on wood projects...however if I don't need to...why would I?

 

[ChuckM]

After some "due diligence," I decided to get a pair of General Tools steel rules with 1/100th grad., one 6" long and one 12" (arriving Monday). The experiment, if failed, will cost me $32 Cdn.

If it's a success, I'll get a Mitutoyo 24" long rule for good measure, which is about $55 Cdn.

All of them are made in USA, and the Amazon reviews were all glowing.

P.S. Starrett? $88 or so for just one 12" steel rule ($199, 24"). I have a Starrett combo square. In use, I don't find it superior to other combo squares that are less than half of its price. When it's out of square, I still have to fix it, just like other more economical ones.

 

[woodbutcherbower]

I aim for doing it right the first time, rather than by way of trial and error.

That's always preferred but I haven't yet found a tool that will make a part cut a bit too short longer.

You mean that you never invested in an ACME wood stretcher?

 

[rmwarren]

I can't measure/mark/cut and consistently get within.5mm to save my life. Where this poses problems for me is mostly working with metal for jiggie type stuff.

Lately I'm relying on gauges of some type (gauge blocks, story sticks, etc.) instead of rulers and if necessary sneaking up on the final dimension.

RMW

Ya I'm all in on this Richard...in my world there is nothing more positive, accurate & repeatable than a hard stop, thus the reason I'm in full support of Kevin's earlier suggestion.

It all depends upon what your needs are, I can easily hold .001" on metal and can hold .015" on wood projects...however if I don't need to...why would I?

Yea Kevin's comment kinda capsulates my approach these days. I don't know if it's sloppiness, inability, or old age but accurately/repeatably measuring & transferring said measurements just isn't working for me.

Luckily, I looked up the other week and noticed this hanging on my tool wall...  [doh]

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99% of my wood cutting takes place now with a track saw and dogs. I can use the dog holes to place fixed stops that can be zero'ed by cutting with the saw & I have a trusted reference point to work from. A story stick or gauge blocks finishes the cycle and removes measurement from the process entirely.

For years I didn't realize why machinists used gauge blocks or things like marking gauges & surface plates to scribe parts, but it's finally sunk in.

RMW

 

[ChuckM]

snip.
You mean that you never invested in an ACME wood stretcher?

I've never tried stretching wood although a couple of techniques are available (scarf joint, e.g.). I either cut a new longer piece (that's what allowance for wastage is for, isn't it?), or make the case smaller/change the design on the fly (no one will know about your change of design).

If I really need to stretch a workpiece, I may try this one:

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[peacefulandpatriotically]

If it's a success, I'll get a Mitutoyo 24" long rule for good measure, which is about $55 Cdn.

All of them are made in USA, and the Amazon reviews were all glowing.

chuck, i'd recommend that you buy mitutoyo products from an authorized retailer.  Unless I am mistaken, amazon is not an authorized mitutoyo dealer and there are tons of counterfeit mitutoyo products listed on amazon.

 

[ChuckM]

Thanks for the heads-up.

This is the kind I had in mind:https://www.amazon.com/Mitutoyo-182-267-Chrome-Tempered-Stainless/dp/B001OBSECK

I thought if something was sold by Amazon, it was supposed to be legit.