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AJB Temple

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I make a rod at the start of each project.
I also make a basic drawing for large things and put the main measurements on it.
I prefer a steel rule to a tape.
If I need a tape I use an Axminster precision which is quite good.
Not fond of knives for marking out, mainly use a sharp pencil, except for dovetails.
I check before I cut.
I batch produce similar components and check them against each other.
I dry assemble before risking glue up. I know some don't, for speed reasons. I do.
 

Paul alan

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;) No, in Wales, you've been using a rod. If you were in the USA, you'd have been using a story pole/ story stick.
We can call it a magic wand if we like, the concept still remains.

Is it obvious how much you tube I watch?
 

Cabinetman

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Pinch sticks, yes Mike I use those all the time, I have a good supply of white, wood Venetian blind slats about an inch across and 3 mm thick which I use, I couldn’t have designed anything better.
The other thing I use is masses of masking tape, it takes a line better than timber, lots and lots of different uses.
For basic marking up of rough boards, to lengths widths and also to highlight defects I use chalk.
 

Rich C

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No, it's not. What he is saying is that if a drawing requires 4 frame pieces at 320mm, if he makes 4 at 321mm then he has precision but not accuracy. The frame will fit as the accuracy error is the same on all components.
I like this image to demonstrate it:
1600416496993.png


Having both is nice, but precision is much more important for woodworking.
 

TheTiddles

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I like this image to demonstrate it:
View attachment 92465

Having both is nice, but precision is much more important for woodworking.
That’s it, I made a set of jenga blocks recently that are also a great example, having them precise is critical, but the only accuracy really important is that the width is 1/3rd the length, the rest is all precision

Aidan
 

Jonm

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Do not be concerned about small gaps in joints where it does not matter and cannot be seen. I did it yesterday at my sons house. Up a scaffold tower cutting a piece of wood between joists for fixing plasterboard around a velux window. I had fixed blocks on the joists to screw the timber to, gaps of 5mm at each end would not have mattered and I cut the timber about 0.5mm too long. Easy to remedy with a chop saw, bit harder with a hand saw on a scaffold tower.
 

RobinBHM

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Just to clarify what I meant:

you could mark out these rafter spacings:

500
45
500
45
500
45
500

with cumulative markings like this:

0
500
545
1045
1090
1590
1635
2135

I used to make extensive use of excel for this -then give it to my guys for marking out.

I couldn't be without excel as a workshop tool.
 

Yojevol

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I like this image to demonstrate it:
View attachment 92465

Having both is nice, but precision is much more important for woodworking.
This graphically shows what I said earlier. Absolute accuracy is not important, relative accuracy is. If one chooses to use Precision instead of Relative Accuracy that's fine by me.
 

MusicMan

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This might be the most basic of basic but while a measurement instrument might not be the most accurate, it will be consistent; always use the same one for the whole project
YES! Especially with a tape measure. In addition to the uncertain behaviour of the hook at the end, the printed-scale process for tape measures is prone to some systematic errors (for example, slight eccentricity of the disc doing the printing). If you buy a tape measure, ensure that it is rated as Class I (a small symbol printed near the start of the tape). Some unclassed ones can be better but you have to calibrate them to know! In general, engraved steel rules are better.

So this is why a rod/story stick is superior (as well as the unambiguity of the mark). It is worth taking some care over making the stick. Make sure it is reasonably straight and square, and mark the marks on it using a square rather than freehand. Knife marks are best.

Despite owning Class 1 certified tapes, and calibrating them against a standard (I need these for musical instrument measuring where absolute numbers are important), I use rods for woodwork.
 

Rich C

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This graphically shows what I said earlier. Absolute accuracy is not important, relative accuracy is. If one chooses to use Precision instead of Relative Accuracy that's fine by me.
Precision is the correct name for that quantity. If you use non-standard terminology you're just going to confuse people.
 

MusicMan

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'Precision' is the correct term in engineering metrology and machining.
 

Rich C

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Just to throw another tool into the mix - for measuring spaces in rooms (e.g. to fit things into alcoves) I have found my cheap laser measure hard to beat. It fits into gaps easily, has way better accuracy than my tape measure, and is much easier to use for long distances.
 

RGIvy

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If I'm using a tape measure for accurately marked measurements I draw the tape out and place the 100mm line (or 1" if you're old school) where I need to measure from and then mark the measurement +100mm, so say if I'm wanting to mark 821mm on a piece of timber using this method I would have to mark it at 921mm on the tape to account for the 100mm at the front end.
And there I thought I was the only one doing this!:)
 
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