Questions you've had, but never got around to asking. Fire away!

look what showed up today.

I’m going to start taking some measurements and comparisons.

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WOOHOO! This is going to be fun!

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Something else I’m interested in looking at will address one of my pet peeves. And that is rattling noises. I’m considering picking up one of these, taking the lead out of a pencil, and shaking the hell out of it to see how much noise it makes.

We use these to certify incubators to make sure they’re not too loud for the little baby’s ears.

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You, my friend, are going into some deep deep deep rabbit holes that non of us have dared to travel. :rofl:

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This could also be very useful in a car. Because you can have an in-cabin rattle and due to sound bouncing off of windows (like crickets) have a hard time pinpointing the source.

Also, if you’ve got other noises going on related to the drivetrain, this can be helpful. For example, a set of wheel bearings wearing down. Which side is it? Placing this sensor in different spots you can help narrow it down.

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How are you going to hold/stabilize each piece for consistency ?

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Not my turf at all but there’s a formula in physics to calculate that sort of thing. Something in Pascals.

But a push button button has a specific resistance (a counter-force) that needs to be calculated first… Then there’s also the size of the area pressure is applied to…

Also, it should be easier to click on a button on top of Mount Everest – but there’s no oxygen!

Okay bye :slight_smile:

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I’m not sure how scientific this is but here’s what I did:
The force gauge has threads on the back, so I mounted it to a piece of acrylic so it would remain stable. Then I manually pushed the knock into it until I heard/felt or saw the lead advance.
I took 12 samples and tossed out the highest and lowest readings, then took the average of those left.

The Smash I feel pretty good about because I actually sampled across 10 different Smash pencils and took the average, so I’m sticking with that number. The others… Who knows? I might have one that’s extraordinarily hard or extraordinarily easy to knock? With a sample size of one, I’d take this with a grain of salt.

Knock Force Measurements:

Newman Super 2 = 0.686Kg
Smash = 1.120Kg
Lion 3150 = 0.857Kg
Ohto PM1503 = 1.208Kg
Pilot H-3003 (retract/extend tip) = 1.367Kg
Pilot H-3003 (lead advancement) = 0.883Kg

Edit::writing_hand:
Hey, and I am completely open to suggestions if anybody has a better way to do this.

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Ahah looks like you found a way. Those numbers looks pretty reasonable to me. Basically you need to exert the same force to push lead forward or to pick up a bottle of milk :slight_smile:

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Excellent, Patrick! Looks like a pretty sure way to me, from all you’ve documented and done. Using a fully mechanical contraption to optimize might reach a slightly more accurate measurement, but I think it’ll be insignificant.

The real trick of this is all about precision and relativity. If you’re very consistent with repeated tests, your findings should be sound. And then it’s all about the comparative analysis to other pencils. :+1:

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Would also like to know which pencils have the loudest click.

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me too - I’m looking for a “decent” sound meter that I can afford. The ones we use at the hospitals are about $900. Which make me kind of leery of buying a $30 one on Amazon.
But it’s coming as soon as I nail down the right meter…

EDIT - I am also working on a “soundproof” box that I will use to do the testing.

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I hope the box is big enough for you to get inside of. I like the image of you in a box wildly shaking MPs to see which one has the scientifically-proven worst rattle.

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You can do voiceover work in those sound proofed closets. :smirk:

I can see it now. Patrick’s mechanical pencil podcast! :grin:

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Insulated fish pond + hole + rubber glove?

:joy:

A.k.a. glove box

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Maybe this

And this

https://shorturl.at/z4ONn

:slightly_smiling_face:

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All you’d really need is a mic shield box and zero out the decible meter to the ambient.

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this is almost exactly what I am working on.

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A $20-30 decibel reader is all you actually need.

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It’s really no surprise that those of us obsessed with mechanical pencils also like specialized tools and measuring devices.

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