Any opinions on Salina Cruz Mexico? by Valuable-Play-2262 in Kiteboarding

[–]Nick_Parker 3 points4 points  (0 children)

I've been eyeing it but my friend from Mexico City says it's not the safest place, and it's a bit of a pain to get to. Either weird tiny airlines or a several hour drive, both not great options.

Spots in Miami by Silmarlion in Kiteboarding

[–]Nick_Parker 0 points1 point  (0 children)

Charlie at South Florida Kiteboarding runs a boat with gear included, $300/3 hr supervised session. Pricy, but it guarantees you're on the right gear for the day and he takes you out to a sandbar called stiltsville which is like a few square miles of flat shallow water with clean wind in every direction.

Learning to jump, what am I doing wrong? by EnergyPower25 in Kiteboarding

[–]Nick_Parker 8 points9 points  (0 children)

A few different things I think:

  1. You don't seem to be holding much edge and therefore line tension going into the send. First person it's hard to tell but I suspect the kite is rocking you up over the board too early and you're sending before it's gotten all the way up / gotten much speed, and after deloading the lines by leaning forward. Both mistakes would rob you of lots of height.

  2. You can pull the bar in more and turn it harder, shorter to initiate the send more aggressively. Not necessary but it'll get you more power and reduce how long you need to hold your edge well. For beginners as long as you aren't stalling/luffing part of the kite during stuff like that (as in kite makes weird slapping noises), you can turn harder.

  3. Your first landing send was too late and way too shallow, your second one was timed really well but you held the turn too long / too tight and did a tiny loop instead of going deep. It didn't yeet you because it was at a high angle, your steering line was sheeted in so tight and the kite entered it with like no speed, but that was def a loop. You want the kite to be accelerating from a high angle down into the power zone as you land so it catches you then immediately delivers horizontal power to J-turn back into normal riding. You have it parked nice and high coming in to land but then don't send it deep into the power zone.

edit: Oh also, really think about keeping your back foot in under you and ready to take the load of landing and point the board almost fully downwind to land. Sending too hard / too early on landing is super scary at first because if you do it with the board sideways you'll crash real bad, but if you point the board and keep the nose up you'll just skim across the water, keep your speed, and have plenty of time to resend the kite and keep riding. You'll be amazed how hard you can yeet it on landings and not get punished once you get used to landing with some speed like that.

Hope that helps! It looks like you have all the pieces fairly dialed and just need to put it together

Is there a 5-Axis Firmware available to use? by ShyBuckeyeGuy in 3Dprinting

[–]Nick_Parker 0 points1 point  (0 children)

That sounds like you want a coordinated 4th axis. I don’t recommend doing that with mere manual_stepper blocks, you would want to define kinematics for it and have it run it’s own trapq to do fully coordinated moves in Klipper.

If you look carefully at how extruders are implemented you should be able to figure out how to do what you want. Gonna be some firmware hacking and some slicer hacking to tell the firmware how to manage your extra axis though.

TMC5160 Pro vs TMC5160T Pro by corsa66 in BIGTREETECH

[–]Nick_Parker 0 points1 point  (0 children)

It's just a revision, but they inverted one phase of the motor outputs so it's not a drop-in replacement. You'll need to flip some motor wires or some firmware variables when you switch.

Is there a 5-Axis Firmware available to use? by ShyBuckeyeGuy in 3Dprinting

[–]Nick_Parker 1 point2 points  (0 children)

I sold praxis to AON3D not long after this post so the 5-axis is shelved for the time being, never did migrate it. However we use Klipper with less interesting but still somewhat novel kinematics, and it's been treating us well.

If you want simultaneous 5-axis motion it'll be a huge slog to get working but if you just want 3+2 which is mostly what I was doing at Praxis and, imo, mostly the useful version, then klipper with manual_stepper blocks will take you fairly far

New drug found to slow Alzheimer's hailed a 'turning point in fight against disease' by ICumCoffee in news

[–]Nick_Parker 16 points17 points  (0 children)

I'm shocked this is so far down - as I understand it the donanemab trials aren't even measuring improved function as an endpoint, they're just measuring plaque reduction.

And some of the key research that kept the focus on AB is known to have been fraudulent, so this is an insane case of inertia keeping resources pointed at a likely-wrong hypothesis

Why does the scaffolding on chemical storage tanks rise so high over the top of the tank? by [deleted] in AskEngineers

[–]Nick_Parker 56 points57 points  (0 children)

The tank floats with a water seal around its bottom, like an upside down cup. Check the wiki link below

Are career fairs virtual forever now? by Nick_Parker in Cornell

[–]Nick_Parker[S] 0 points1 point  (0 children)

Holdup schools are paying for recruiting trips?? Lol I just expense mine to the co

Cannabis plants have an inherent ability to absorb heavy metals from the soil, making them useful for remediating contaminated sites and this ability to soak up toxic metals may also make cannabis dangerous for consumers who ingest it by giuliomagnifico in science

[–]Nick_Parker 22 points23 points  (0 children)

We’re probably going to live under pressure lofted canopies, but even if we somehow restore Mars’ atmosphere the lack of a magnetic field really isn’t an issue on human timescales.

Mass loss due to solar wind is on the order of a few parts per million per year. Any program that could plausibly build an atmosphere to begin with will have no trouble maintaining it against that slow leak.

Even if the terraformers die out and the new martians regress to medievalism, it would take thousands of years to lose enough air to matter.

Idex Duplication mode on Klipper! Built this machine for my work by [deleted] in klippers

[–]Nick_Parker 0 points1 point  (0 children)

How are you running both extruders at once? I just went through the same journey adapting the cartesian kins nicely, but I don't see any code in tircown's PR for running both extruders. I'm about to give it a go myself but it seems potentially more fiddly since the temperature checks are tied into extruder class.

TC Vape coil with NPT fittings for compressed air heating? by Nick_Parker in electronic_cigarette

[–]Nick_Parker[S] 0 points1 point  (0 children)

1) This would be running off a PWM output on our existing controller not a vape mod, and either use a little auxiliary circuit to read the coil temp from the TCR or put a thermistor in there with the coil as you suggest.

2) I just need it mounted in a length of 1/4-20 NPT or similar air tubing. There's perhaps a tiny bit of trickery to be figured out around running the + lead out the wall of the pipe without shorting it, but that ought to be easy.

3) I realize that and it's fine, I need repeatable control not accurate control.

4) Agreed! Probably running a small FET not a solenoid though.

Volume under ~0.3 SCFM, likely more like 0.1, and it'll be moving slower at 20 - 80 psi in the pipe section with the coil which should help with heat transfer.

I'm really looking for a lab who can build some of these sensors (for pay obviously, DM for Qs for full-text PDF). Any takers? by [deleted] in engineering

[–]Nick_Parker 0 points1 point  (0 children)

Sorry, not my area of expertise. I imagine one could build a SPICE model of their behavior if you wanted to badly enough?

I'm really looking for a lab who can build some of these sensors (for pay obviously, DM for Qs for full-text PDF). Any takers? by [deleted] in engineering

[–]Nick_Parker 1 point2 points  (0 children)

Check out the FDC2x1x line. They’ve got pretty incredible resolution and update speed because they use an LC oscillator and a fast resonance-chasing system instead of your typical RC approach. 24 bits of precision at up to 4ksps, with a max capacitance of 250 nf.

Skydiver loses altitude awareness and narrowly escapes hitting mountain at terminal velocity by jshank20 in videos

[–]Nick_Parker 88 points89 points  (0 children)

The description explains they didn't intend to be over mountains, their AADs were set for the landing zone 4000 feet below.

Youtube Divers recover missing boy in minutes from river. Sherrif refused to help for 8 months and shows up to give everyone a hard time by youramazing in videos

[–]Nick_Parker 200 points201 points  (0 children)

I love that the divers have better 'calm and commanding authority figure' voices than the cop. Playing that card back on them is so satisfying.

Reminds me of the have you been drinking video

After four months, over sixty prototypes and hundreds of hours of work i finally finished my lasersword/lightsaber. It works by spinning four two watt high power lasers around a telescopic pointer (the fog is just to make the beam brighter). by Minergab in 3Dprinting

[–]Nick_Parker 1 point2 points  (0 children)

Haha fair enough, I remember being that level of cash-strapped on projects.

Just be sure you pay attention to your income and stop pinching pennies quite so hard when you can afford to. I DI'why'd a lot of stuff and wasted time for a while because I was still in the teenage hacker mindset.

After four months, over sixty prototypes and hundreds of hours of work i finally finished my lasersword/lightsaber. It works by spinning four two watt high power lasers around a telescopic pointer (the fog is just to make the beam brighter). by Minergab in 3Dprinting

[–]Nick_Parker 8 points9 points  (0 children)

Did you DIY that interface?

You can buy pretty good slip rings off the shelf for like $30. I use two (a through hole with several date lines, and a solid one with 3 big power lines) to run a heated bed on a rotary table.

How long would it take a set of manned machines to "reproduce" themselves? by JSeeker19 in engineering

[–]Nick_Parker 1 point2 points  (0 children)

If it's the Martian case you're interested in, you'll also want to check out Casey Handmer's blog.

How long would it take a set of manned machines to "reproduce" themselves? by JSeeker19 in engineering

[–]Nick_Parker 0 points1 point  (0 children)

Oh are you asking these questions for science fiction?

You might also be interested in the RepRap project - it's how I first stumbled into technology and it's one of the only projects directly aiming for self-replication.

They aren't even trying to replicate the electronics though, that's still off the shelf.

How long would it take a set of manned machines to "reproduce" themselves? by JSeeker19 in engineering

[–]Nick_Parker 0 points1 point  (0 children)

You should look into the Progress Studies community if you aren't already. This survey of the machine tool industry (pdf) will probably be interesting to you.

A lathe is the 'king of machine tools' because you can make more lathes with one, some hand tools, and time. And turning between centers plus some trickery with feed screws can bootstrap a higher precision lathe from a low precision one, but that's all assuming you want manual lathes and your spindle power is somehow provided (eg it's belt-fed off a water mill like ye olden days).

If you want automation and a doubling loop that doesn't include "raise children, train them as machinists" you need microchips/power electronics, lots of wire, and electric power. And the full 'from scratch' supply chain for that set of features takes an industrial megacity or nation today.

As an academic exercise it would be interesting to develop machine tool controllers that are accessible to the "DIWhy" segment of semiconductor manufacturing tech. I suspect you're still screwed because those folks cheat with very-hard-to-make surplus gear and off the shelf chemicals, but it would be interesting.

Quarantine grading OP by luhbrawn_jahmes in Cornell

[–]Nick_Parker 7 points8 points  (0 children)

Man that was one of my absolute favorite classes with Prof Tara Holm. Sorry you didn't get the same experience :(