A large amount of the energy consumed by planes is at takeoff, could we reduce the onboard battery size by using a cable system similar to what is used on aircraft carriers to launch the planes? Or would there be too much wear and tear / maintenance for this to be feasible? Could “shore” power be supplied instead? Basically a battery bank or generator to power the plane as it gets up to speed but not yet airborne.

is it possible to have a blower fan similar like this (where they are normally pulling air in from the top or bottom and pushing it out a side.) To instead make it PULL air from one side with the rest closed and blow it out the top while still keeping the slim line blower form factor?

Hello Everyone,

I recently accepted a new position as a facilities engineer with a company that involves various thermal spray processes. My expertise prior was more in controls & electrical engineering. That's why I am being given and accepting this role, as much of the equipment & processes require retrofitting and upgrade.

However, the role also includes managing thermal spray booths that utilize gases such as compressed air, oxygen, hydrogen & argon. Industrial gas plumbing & such is an area I am largely unfamiliar with, besides electrical control elements such as solenoids and sensors. I understand some basics, such as the needs for purging gas control cabinets or providing flashback protection, but I am far from an expert on this.

I believe I need to become an expert in this area to safely and successful perform this role in all of its aspects. To that end, can anyone recommend good texts for designing, mantaining & repairing such gas lines, from a facilities perspective? I'm a fast learner and I'm not afraid of putting in work to get where I need to. Anything that can be recommended; textbooks, online courses, YouTube series, etc. I want every resource I can get my hands on.

Thank you in advance for your time and help! It is greatly appreciated.

Also, if there are any thermal spray engineers here, can you recommend resources on learning the thermal spray coating itself? I am already looking into acquiring the ASM Volume 5a Handbook, as well as other materials from the Thermal Spray Society, but anything else would be extremely welcome. There are other engineers handling the spray coating process but I would like to learn it myself.

I want to measure the hydraulic stiffness in underpressure, 0.3 bara. In the past, we've done this by using a syringe, filling everything with water, and correlating the pressure readings to the volume displacement of the syringe. This was done at atmospheric pressure so the syringe was decent enough. However, a standard syringe, that you can get in any pharmacy, leaks in 0.3 bara.

I was thinking of using a pneumatic piston (they're dirt cheap) and just replace the syringe in my setup with it. Obviously, all of them have max pressure spec but can't find any info on min pressure. So my question would be did someone ever try something like this? Do you think it would work?

Hi y’all,

I have an idea for a loom-type machine that incorporates knots to create textile patterns as opposed to weaving. Ive made projects using this technique by hand with amazing outcomes, and I need a way to speed up this process as it takes hundreds of hours. The tying mechanism itself, which is a simple overhand or underhand, is posing quite the challenge for me. I do have access to a 3D printer, however the end result will be completely manual and non electronic.

I have no official education outside of medicine and know 0 about engineering as a whole. I definitely need someone smarter than me to help me out lol. I’m willing to financially compensate anyone for their time and ideas.

I have a first generation Toyota sequoia that has a design flaw that can cause the lower ball joint to fail and the wheel to break off. Many other people have vehicles with this flaw as well and I've seen a good number of these vehicles on the side of the road with their wheel broken off.

I want help somehow creating a bracket that inverts the lower ball joint so that it goes from being under tension to being under compression.

There is a company that makes a spindle that has the lower ball joint flipped over, but they're about $7000 just for the part. I believe it's solo motorsports and there's is more intended for racing. This seems to me to be a proof of concept.

I think it would be fairly easy to make a bolt on bracket that allows you to flip over the lower ball joint.

The lbj bolts are also a failure point and since this could change the stresses on the bolts, I think an extra piece that hooks onto the spindle could be a good idea. That or an adhesive in addition to the bolts or some welding.

There's an online support community for this issue. I bet lots of people on there would buy a product like this. I know I would lol.

I wanted to add pictures and links but it looks like that's not an option.

These are all still very popular vehicles that overall last forever, except for this one issue that scares me even though I've replaced those parts. This applies to sequoias, tundras, Tacomas and 4 runners.

Alternatively, if anyone just knows if there's a spindle from a different vehicle that fits and does the same job that would be awesome too.

So anything interested in making this? I bet a good amount of people would pre-order if this was made. I know I would lol.

Edit to add: My main idea is to take used lower ball joints as the basis for the bracket, then make some cuts and welds to that. Or just buy the lower ball joint bracket from later Toyotas and somehow retrofit that to the older lbj body. This is because the tie rod end connects to the body of the lbj, not directly to the spindle. Apparently I can invite links now too so I'll add some in a while.

I've found several books on the internet, but frankly I'm unsure of the quality. Could be good. could be bad.

So any recommendations? Preferably one with diagrams and how they managed to make via canal without the sea drowning them while using mostly rudimentary tech.

I have a component that moves that carries a relatively weak audio signal, so no high voltage or amperage.

I want to slide/move the component while keeping the leads coming from it in the circuit.

For my prototype I am going to use a short brass rod inside a longer brass tube with a notch cut in it. One brass tube awould be at each end of the component with the leads soldered to the brass riod. The brass rod inside the tube will act as a slide like a drawer and also as an electrical conductor to carry a weak audio signal.

It will be exposed to air. It will be exposed to fingers potentially touching it, so no wires because it may cause tangling or jamming.

I know this kind of thing has to be done routinely inside equipment, though probably using some kind of ribbon cable. I want to avoid cables and wires, and have a conductive slide instead.

What ready made things are available and what are they called?

I have also considered using telescoping antennas but to find ones that fit my specs is impossible (very short segments… 1/2 inch to an Inch that telescopes out to about 8 inches.)

Oh to be clear the component is square and moves straight in one directional plane about 8 inches. I’m using brass because copper is too soft and aluminum on aluminum doesn’t conduct well after it oxidizes.

Also if I do go with brass, what is the best lubricant that conducts electricity and reduce brass corrosion while not messy or runny?

I want to power a small esp 32 project with a battery, but I want it to work like my phone- where I can plug/unplug it from a usb cable whenever without causing damage or disruption. Google suggests to4055 modules but I can’t get a straight answer on if it’s safe to unplug it.

I think I need something with power path management? Is there a better option or can a tp4056 actually do what I need?

I went 4 months on my sailboat just bagging my groceries and sticking them in the water. I live in SE Alaska and the water stays cold. Join I was curious if I could build an insulated box with aluminum on the inside lining that has channels. And either pump cold water through constantly or using a heat exchanger. That way I would have an icebox for a fraction of the energy on my batteries.

If you capture cooling tower vapor plumes, condense the water and return it to the basin, is that water hot? Or has the vapor had enough time to reject the heat to the surrounding air?

Been researching this for a while now because I'm trying to come up with a solution. Silicone and EPDM are both great, but from talking to a manufacturer it'll only last 20 years under idea conditions and I'd like to be double that. Metal crush gaskets are interesting, but I feel like the minute changes in the glass with thermal movement, and the lack of torque you could apply, would make it leak. There's a ton of materials out there, so I'm looking for ideas to chase down.

I feel like if you set it up correctly making individual cuts would be just as fast as a bunch of CNC machines not to mention cheaper. You could have parts get cut and then exit directly on the assembly line, eliminating the need for a worker. Plus if each machine always has a part in it then output should be no faster than if each of those spots were taken by CNCs. So what am I missing?

I'm a very small home business that's just starting, I'm not a vast corporation with hundreds of employees. I'm thinking of creating small bespoke handheld devices with FPGA technology as well as PCBs/circuit design. I want to learn more about the process of finding and hiring an engineer to get a ballpark figure and learn more about what they can offer. It would be a temporary contract/consultancy it wouldn't necessarily be a business partnership depending on the situation. I'm just trying to get an idea of what it would be first, it's still in it's early stages. I'm not opposed to remote work. But I feel like it would benefit me more by seeing them in person and viewing what they do to learn more and understand it myself because I have no formal education (in engineering) and would like to understand it myself. I've tried putting job ads on the sites of my universities but it's not really been that successful. Is there anything else I can do?

image here:

It is for the electro valve that closes and opens with electro magnet.

Making something up here for simplicity's/explanation's sake.

Say you've made an automated plant-growing system. It controls watering, lighting, nutrients, temperature, everything you could want it to do. It's based on an Arduino Uno.

If you wanted to move that system to a bespoke board for whatever reason, how involved is that process? What would be required to make that happen? I would imagine it's hugely involved with low-level programming, are there processor chips that come with their own interface for programming like the Arduino but are more commercial-oriented? IE you could buy a "raw" processing board with the low-level programming done and only focus on high-level programming in C?

I'm a Mech E and have never dabbled in computer/electrical deeper than dicking about with an Arduino so I'm fairly lost on the process.

In one of the opening pages of the Westinghouse Transmission and Distribution Reference Book (1950), it says that in 1925, the average lb of coal burned per kWH of energy generated was 2lbs, but that it is currently (when it was written), around 1.3lbs. A quick google search shows that # to be 1.14lbs/kWH in 2022. So a 35% reduction in 25 years but only a 12% reduction in 70+ years since. With how much more efficient everything else has gotten, why can’t the same be said of coal fire plants?

How do you calculate gauge to inches and vice versa?

Google results say to consult a lookup chart. That's not the question. What is the mathematical formula?

I understand that metal density or some kind of constant related to the metallurgy is included in the calculation.

I see some evidence to suggest that logarithm is used as an approximate. I see examples of people who have derived approximate formulas from lookup tables. The question is about the theoretical calculation, not the approximate.

It’s written in Dutch and seems to be a technical sheet.. The date on it suggests it's from 1942. ChatGPT seems of not much help.

Document: https://imgur.com/c3FQhBQ

The title reads: "Determination of slide positions and lapping"

G’day, i will be making a solenoid with a stroke of 150mm and needs to produce at least 10N. My plan is to run it from an 11.1v 2000Mah stick battery for compactness and ease of recharging. I will also be using a surefire pressure pad or just a regular pic rail accessory push button from china to activate the solenoid.

My main issue is, I want to have the solenoid wired in such a way that when the button is pressed, it actuates the solenoid and the spring mechanism returns it to the starting position even if the button is continuously held. Each individual push of the button cycles the mechanism as to not burn out the coil or overload the battery by holding the button.

I’ve tried using Chat GPT and Engineering GPT’s but the explanations are so different each time that I don’t know what to trust.

I have minimal knowledge in electrical engineering and would love the most simple and direct solution for my project. A diagram would blow my mind also! Thanks guys❤️

Edit: thank you all for the answers! Have some reading to do now

We have a box of titanium plates to get rid of at work, and don't want to toss it into the standard metal recycling stream, incase it gets sorted as Alu etc and contaminates that stream. Does anyone have any ideas where/how to recycle it?

I tried to visualise these devices and came to the conclusion that a CCD never wants to leave packets of charge carriers behind, while a logic circuit (NAND) is more concerned about not to have parasitic resistors in the channel between the gates, but also does not want parasitic capacity between the gates.

Hey everyone! I’m looking at building a buoy (filled with sensors) that can be opened and closed for maintenance, whilst maintaining a water tight seal, I don’t even know the first place to look. Would appreciate any tips, dms, websites, subreddits,YouTube videos or books to read about the topic!

I’m also from Australia!

Thank you very much for your time!!

Hi, Just for fun and to try and do some experiments I'm trying to build something like a "jack in the box" but with a boxing glove (straight out of the cartoons).

I have a strong compression spring attached to a base, inside the base I have a weaker EXTENSION spring attached to the glove.

I want the strong spring to push, hit the hard stop and with the accumulated momentum extend the inner-weaker spring to "shoot and retract" the punching glove (like a slinky yoyo).

If my strong spring has at its compressed state a force F. and the weak spring in its relaxed state has a tension of T, I assume any F > T will create the extension of the weak spring.

If I match the force F to the "suggested max load" of the weak spring (which I assume extends it to its suggested max deflection). Will that be the only variable?

I am trying to make calculations and I feel I am oversimplifying things since I am only considering the spring forces and not masses or anything. . .

However, I want to know how to play with these forces so that it remains a toy and not a black-eye generator.

IMAGE FOR REFERENCE

Intro

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Follow the instructions below and list the name of your Metropolitan Statistical Area and its corresponding RPP.

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!!! NOTE: use Markdown Mode for this to format correctly!

**Job Title:** Design Engineer

**Industry:** Medical devices

**Specialization:** (optional)

**Remote Work %:** (go into office every day) 0 / 25 / 50 / 75 / 100% (fully remote)

**Approx. Company Size (optional):** e.g. 51-200 employees, < 1,000 employees

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**Country:** USA

**Cost of Living:** Los Angeles-Long Beach-Anaheim, CA (Metropolitan Statistical Area), 117.1

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**401(k) / Retirement Plan Match:** 100% match for first 3% contributed, 50% for next 3%

Why do cars in hot regions not have a reflective roof to reduce radiation from the sun? It seems logical but I have never seen it.

A quick calculation: a car roof of 1.5x1.5m at the equator receiving 1000/m² is receiving 2250W. It would seem like a good idea to reflect that rather than get the Aircon to remove it. Edit: after trying some of the suggestion made I realised that there is another effect not mentioned in the comments The equation for heat loss due to thermal radiation is given by the Stefan-Boltzmann law. In short, the heat loss due to radiation of the roof is proportional to the (temp of roof ^4 - temp of surroundings ^4) which means that there will be a much greater loss of heat emitted upwards that downwards because the roof insulation will keep a high temperature immediately under the roof. Thisjis not the only factor but one worth mentioning.

I've been reading a lot about potential issues with large-scale solar power. The basic idea is that solar is has issues because it generates surplus power in the day, so storage for night use becomes an issue. I know that lithium batteries are a very popular answer right now, but I'm interested in finding out if there are other viable alternatives.

Could hydrogen be used to store excess power from solar plants? Would it be feasible to generate hydrogen with solar power, then burn the hydrogen at night?

The maximum resolution with a 1 meter baseline should be in the scale of kilometers.

As a reminder, /r/AskEngineers normal restrictions for career related posts are severely relaxed for this thread, so feel free to ask about intra-office politics, salaries, or just about anything else related to your job!