What is your preferred measurement scale?

[Chris Parks]

I came across this in my YT feed which I found interesting, the US is a signatory to the metric system......

[Rod Sheridan]

Yes, the US has used metric standards for ages now.........Makes sense however...........Regards, Rod.

[Robert Engel]

Imperial only because its ingrained in my brain.

Metric when i need to divide or space something out ;-)

[Marshall Harrison]

I can't seem to visualize metric lengths. Tell me something is 6" and I get it but I can't relate 152mm to how big that actually is.

I think mm would be amore accurate and I have considered changing but I just can get a grasp on how big.small something is when stated in millimeters.

[Leo Graywacz]

It's easier to split 10" three ways? The closest you'll get on most inch rules is 3 11/32" - but very few woodworkers could do that quickly and easily in their head.

So, quickly now, divide a foot five ways in fractional inches.

My point is that in any system of measurement lots of division problems don't have "natural" answers. This is why we invented first the long division algorithm (for decimal systems!), and later was a good reason to carry a slide rule (decimal again), and eventually calculators.

I don't need to do it in my head. I take my rule and put the hook on one edge and angle the rule down to the 15" mark on the other edge. Then I just put ticks at the 3" marks. Now it's divided in 5 equal spaces and no math was required.

[William Adams]

It's easier to split 10" three ways?

Yes, 3 and 1/3rd inches --- 1/3rd of an inch is 24 points, so I'd go and get a DTP (PostScript) points ruler and use that.

[Jim Becker]

I can't seem to visualize metric lengths. Tell me something is 6" and I get it but I can't relate 152mm to how big that actually is.

I think mm would be amore accurate and I have considered changing but I just can get a grasp on how big.small something is when stated in millimeters.

I think this is probably the biggest barrier to many folks with adopting metric...our minds. Many of us in the US grew up without metric in mind or in learning. That said, I'm slowly but surely overcoming that by actually using the system. And I really like it. So my singular recommendation for anyone wanting to switch to another measurement scale is to commit to it and actually use it for a period of time, even if there are some struggles. Do it because you want to, not because someone else did it.

[Carlos Alvarez]

That's my problem with middle sizes in metric. I can easily visualize 10mm because I use metric hand tools a lot. I can easily visualize a meter because it's basically a yard plus a bit. I can easily visualize a kilometer, which is just over half a mile. I cannot even begin to visualize 152mm. The best I can do is convert it in my head and see that it's six inches.

[William Adams]

The thing is, I've actually been trying to use metric for all my CNC stuff, but haven't had any luck in finding out what the customary measurement units are, nor the specifics of metric versions of formulas, nor any endmill vendors who specify chiploads in metric.

https://sawmillcreek.org/showthread....-for-machining

[Steve Demuth]

Leo,

That's a great technique if the board you're trying to mark is at least 9" wide. Try it on a 3" wide board, or better yet, try to divide an 8' by 4' sheet of ply that way, and let me know how it goes.

[Steve Demuth]

Yes, 3 and 1/3rd inches --- 1/3rd of an inch is 24 points, so I'd go and get a DTP (PostScript) points ruler and use that.

There must be some English measurement system that works for any fractional base, eh? Wonder where we go for 7ths?

[William Adams]

For 7ths I'd use Leo's technique --- if need be, using the PostScript points ruler on a small part.

[Steve Demuth]

For 7ths I'd use Leo's technique --- if need be, using the PostScript points ruler on a small part.

To each his or her own methods. If it works for you, that's what matters. But again, that technique only works if the piece you want divide has a fairly balanced length/ width ratio. To divide a 10" board into sevenths using 14" as your scale, you need to be just shy of square to land that 14" hypotenuse. It would work for relatively few divisions in my shop.

[Glen Gunderson]

Never mind the fact that metric is even more compatible with that trick because it's all whole numbers. Need to divide 120mm into 1/5ths and don't want to do the math of 24mm x 5? You don't need to go all the way up to 150mm (assuming your board can even handle a hypotenuse that's 25% longer than its length) when you can just angle your rule to 125mm and mark every 25mm. Need to divide 127mm into 7? Move up to 140mm and mark every 20mm.

[Matt Mattingley]

To stir things up a little more, when I started out I was taught degrees minutes and seconds as primary measuring for all angles.

About 15-20 years ago, everything started changing to decimals of degree. One of my math teachers said a heptagon (7 equal angles) is 51° 25’ 40”8 (Or 51° 25 minutes 42.8 seconds) or 51.42857°

So, do you like using degrees minutes and seconds or do you like using degrees a decimal?

And sure there is the metric radian(which is another ball of wax)