I’ve got both of those on hand - I’ll check the site out too! Many thanks! (Didn’t put the citronella on the cats, just the wood frame of the play area.) 
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The older brother of a childhood friend of mine is a shipwright with Gannon & Benjamin. I am always awed by the work they do. His instagram is nearly all progress shots, if you want to climb back into the rabbit hole sometime.
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Wow, that is some beautiful work!
I have visited the boat building warren on a number of occasions, and there is always so much to learn there!
As an aside, this http://cwb.org/ is where my wife and I had our west coast wedding celebration. There web site was not nearly as slick back then and had lots of pictures of old wooden boats.
Build a bat box in the area ! (With a glowforge it’d be quick) A single bat can eat up to 1,200 mosquito-sized insects every hour, and each bat usually eats 6,000 to 8,000 insects each night!
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Got 'em!!! I just wish they’d invite a few more friends!
I watch them come pouring out of the neighbor’s chimney every evening at dusk. If i happen to be outside, they shoot straight for my head with some crazy fantastic aerial dogfight maneuvers.
That really freaked me out the first few times it happened, until I realized the little bats were after the swarm of mosquitoes that gather around me for a snack anytime I step outside…unfortunately, I’m one of those people. Very tasty. (At least to mosquitoes.)
If I were a better sport I could probably eradicate the mosquito population single-handedly, by just stepping outside every night, and acting as bait for the bats. (I’ve actually stopped ducking now - they never even brush you with a wing tip.)
But they’d probably get too fat to fly.
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Not exactly a tutorial, but a good overview on cam’s.
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That’s excellent.
Most of us will probably never need to worry about discontinuities the the profile that cause infinite jerk. haha
But a great overview and some unique cam paths i hadn’t thought of. I definitely will have to try a couple of them.
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I remember having to make all these charts in school. Good times 
Yea there are some cool designs for cam’s that I never heard of.
Remember when I was 17 learning that the rate of change of acceleration over time was called jerk. Other than the usual Big Bang Theory style banter in calling our friends a “third derivative of position”, we never had to use the term in practice.
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We had a program that would derive them for you. You could call out trapezoidal, sin, or poly transfer point and it makes a neat little plot of the forces.
I’ll have to go see if I can find it.
Of course the teacher only showed us this after we had done it by hand a million times… Haha
Edit: Found it. Its called Dynacam.
Here is a link to my copy. Or you can go to their website and make up a user name and login and get a copy too. Its just a student version, so it wont output the plot, but it will get you a general idea
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Awesome! Now I’m going to have to play with this!
Oh, google thinks it is a virus. So i cant share it. Hmm ill see what i can do.
how about dropbox?
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That could be my superhero name! Now I need powers… is laser vision too obvious?
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I’ve only learned jerk as a tech term recently. OnO of the settings on the motion card of my cnc
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Yep. Jerk is also used on 3d printers. Turns out you can’t start or stop a pound or more of bed or print head instantly, and you can’t even start it accelerating from one microsecond to the next. Darn matter.
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The first, second, and third derivatives of jerk have even better names.
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Curiosity activated. Google to the rescue:
“The fourth derivative of an object’s displacement (the rate of change of jerk) is known as snap (also known as jounce), the fifth derivative (the rate of change of snap) is crackle, and – you’ve guessed it – the sixth derivative of displacement is pop. As far as I can tell, none of these are commonly used.”
"Since force (F = ma) is rate of change of momentum (p, symbol clashes with pop) it seems necessary to find terms for higher derivatives of force too. So far yank (symbol Y) has been
suggested for rate of change of force, tug (symbol T) for rate of change of yank, snatch (symbol S) for rate of change of tug and shake (symbol Sh) for rate of change of snatch. Needless to
say, none of these are in any kind of standards, yet. We just made them up on
usenet.
Now class, repeat after me. . .
Momentum equals mass times velocity!
Force equals mass times acceleration!
Yank equals mass times jerk!
Tug equals mass times snap!
Snatch equals mass times crackle!
Shake equals mass times pop!!"
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I think you bunch of jerks have effectively yanked this thread off course, time to snap to and put a clamp on it.
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I see what you did there…
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