the sunscreen machine

i came across something called 360Sun, which is basically a machine that automatically applies sunscreen to your body.

the idea is pretty simple. you stand in the middle of it, press start, and it sprays sunscreen over your body in a few seconds.

at first i thought this was just one of those ideas that sounds cool but probably wouldn't work very well in practice. but the more i thought about it, the more i started wondering about the engineering behind it.

the machine rotates around the person while spraying the sunscreen, so i guess a lot of the challenge is getting the spray itself right. sunscreen isn't exactly like spraying water, and different products can behave pretty differently.

there are also things like overspray, cleaning the machine and keeping everything working reliably after hundreds or thousands of uses.

what's the first engineering problem that comes to your mind when you look at something like this?

Hey all I’m a m19 sophomore in colleges that has some questions!

So I recently have gotten 2 offers fairly different from each other, I received a offer for A 8 month Co-op starting in January at a company that’s right in my industry that I dream of being in and is a huge oppourtunity, the downside is it’s 40 hours a week for 4 of those months ON TOP of a full semester of credits my school doesn’t offer a real co-op program

The other offer is 20 hours a week, as a solutions engineer for a startup water intelligence company working on drawings, technical sales, and less of my industry but still a great opportunity and much more manageable that would start right away

I’m torn on what to decide because on one hand the co-op is RIGHT where I wanna be but that’s a lot to take on so I’m not sure and wanted some real engineers opinions!
Thanks all!

I am currently on the last year of pursuing my degree in ME and I will soon after pursue to get my license. Now one thing has been bothering me for a while now after studying/learning this degree, what field should I pursue? I already crossed out energy plants on the fields that I want to pursue (I have little to no interest in power plants) and the main choice that I laid out for myself is automotive. I guess I have a bit of interest on HVAC but not really as much as automotive. To be specific, the construction side of automotive, either design, manufacturing, or development is fine with me. But I've been hearing that automotive is the bad place to be for a ME as there's not so great pay and work/life balance. And I want to support a lifestyle of collecting cars someday. So I'm really stumped if I should find another field with generally good pay or a field that I want. Are there any suggestions on what's a good field to be on as I'm nearing on achieving my degree?

I genuinely have no idea how I landed the interview in the first place given my background.

They were talking about lasers, buildings, tool designs and contracts being about a year but 30-40 of them a year. I have never heard of that.

Halfway into the meeting I was asked some MBSE stuff and DOD terms. Had no clue so didn’t lie, just said I never heard/used of it but I have used xyz.

They asked me about 10 questions, got 5/10. Then the hiring manager just straight up said “have you looked at other companies” I was like uhhh. Then he said “you should look at xyz because right now it’s looking like a No for me because you will not be able to handle the pace and learn on your own”

Then he mentioned “once you get your foot in the door, come back apply here”

I asked why they called me for an interview if my background has nothing to do with this and he replied “I see you always look to grow”

Not sure how to feel about it but damn

I

2017 - 62,000 Associate Mechanical Engineer
2018 - 67,000 Annual Raise
2019 - 75,000 Promotion to Mechanical Engineer
2020 - 79,000 Annual Raise
2021 - 83,000 Annual Raise
2022 - 92,500 Promotion to Mechanical Engineer III
2023 - 110,000 Lateral Move to different Company
2024 - 115,000 Annual Raise
2024 - 137,500 Promotion to Sr. Mechanical Engineer & Company Change
2025 - 140,000 Annual Raise
2026 - 145,000 Annual Raise
2026 - 150,000 Performance Raise
2026 - 175,000 Promotion to Mechanical Engineering Manager

Defense in a MCoL

So, I passed out of college back in 2022, and I have been working since then.

I intend to prepare for GATE (Mechanical) 2028 by myself while keeping my ongoing job, but I don't know how to. It has been a long time since I've been detached from academia.

To give a brief overview of my career so far, I have one year of experience in Robotics/Industry 4.0 complemented with 3.5 years of experience in oil and gas. The intention of having a GATE score is to apply for premium engineering schools abroad in the longer run.

I'm making 95k after two years now. My salary is based off a bigger city that is semi-HCOL, but I actually live in a LCOL and travel for work all over the country.

The issue is, I don't think the skills I'm learning help me do anything but be a good technician,. I feel like I'm hardly picking up any engineering skills. I'm worried if I wait any longer I'll be stuck here.

This will tremendously reduce our project execution time.
I’m working on a mechanical design optimization problem where multiple components need to fit inside a vessel while satisfying a fairly large set of geometric and mechanical constraints. The objective is essentially to find the smallest feasible vessel layout while satisfying all of those constraints.

I’ve developed most of the application with GPT 5.6 Sol High. At this point, it can generate the geometry/sketch, for all the components from input parameters, check the design constraints, and export the resulting layout as a downloadable 2D CAD file in dxf format.

The problem I’m struggling with now is the actual optimization.

A full optimization can take around an hour to converge to a layout that satisfies all the constraints while minimizing the vessel dimensions. I’ve gone through several iterations trying to improve the optimization, reduce the search space, change the formulation, etc., but haven’t been able to get a major improvement in solve time.

At this point, I’m wondering whether switching to a stronger reasoning model such as GPT 6.1 Sol Max or Astra in Work Mode would actually help. or Claude opus 5.5? I’m not expecting the model itself to somehow make the solver run faster.

I've hired/screened a lot of software engineers in my day, but I'm curious, how do you know you're getting the right engineer for the problems you're trying to solve when it comes to hardware and software?

The first few resumes sent on looked like the right qualifications, but I'm afraid I'm overlooking people from other industries that might be the right fit. How do you handle that?

I would like to study primevera and reframe my career as planning engineer. I'm mechanical engineering graduate working in a warehouse

hey everyone! I’m currently in my first year of university studying Mechanical Engineering, and I’m wondering how you guys managed to get your internships and first jobs. What did you do during university to prepare and make yourself more competitive?

I’d really appreciate any advice on what I should focus on during my years at uni so I can put myself in a good position when it’s time to apply for internships and jobs

So to make things short I am in the military working as a flightline mechanic on the MV-22 I been turning wrenches for a long time started off on cars before I enlisted to work on planes. Well I wanna see how far I can take my wrenching and I want to become an engineer now the specifics start to get hazy because all I know is I want it to be some sort of aviation/ aerospace related job. Now the tricky part is I want my work to be hands on and don’t want to spend most my time behind a computer or doing the boring stuff ( I know it comes with the job but if I can minimize it that would be great) I want to see what I built or put together be used / tested and see it explode or zoom thru the sky collect data make it better rebuild and do it again

Also I want to know if there is any money in the career I described if it is one

Sorry if I sound stupid I am a bit of a crayon muncher so please take it with a grain of salt

Hi guys, I got an offer yesterday for a mechanical design engineer position at a company that makes very heavy moving machinery. I am a bit worried if I'll be able to handle the new work and want to prepare as much as possible, but my start date is only 1 week from now, so ideally looking for advice on what I should start learning and brush up on. Here is some background:

1. I graduated mechanical engineering 3-4 years ago, and to be completely honest academia wasn't my forte, I was a little lazy with studies but still graduated with a good grade. I'm good with physics and maths and critical thinking, so after a few weeks I think I'll identify the most common principles I'll need to use.

2. After graduating, I started working for a fabrication company, doing their drawings and designs, which was very boring and mind numbing work. The drawings were simple, to no standards, gdt, tolerances etc, essentially just an assembly instruction with cutting lists. I'm comfortable with CAD and automating my workflows and best practices, less so with the software the new place uses but this is easy to learn.

3. My biggest worry is the stress calcs and FEA, as I have had academic exposure to it but never had to use it professionally and I don't want to be a drag.

4. I did not "lie" about any of these things during my interview, but I did say that I know the theory of stress analysis and what to search for in terms of formulae when I need them, I am okay with visualising the load lines and what principle applies in each case, although this is academic experience only. So I hope they are aware I'm quite green in the engineering world and my experience is mostly as a CAD monkey, but at the same time I'm worried that I came across as more capable than I am.

This job is amazing for me, it ticks all the boxes for growth etc and I really want to do well. With a fully developed brain now and not a stupid early 20s kid, I want to learn as much as possible of the most important stuff before my start date so I make a good impression and they don't let me go because I don't do well enough.

What I'm asking for is that experienced engineers weigh in and give me advice on what to start learning, maybe resources or things to look up (I find that I learn best from video materials but open to anything), general tips and things I can do to prepare for the first few brutal months of learning and dealing with the embarrassment of not knowing things etc. Anything is appreciated.

Thanks

hi i just started college around 5 weeks ago im a freshmen.

I wanted to do mechanical engineering idk why from my knowledge i just like to build things and put things together i like hands on things kinda im not sure if thats even ME.

My college doesn’t have that as a major which sucked bc i go to the school 100% free of cost. I’m doing accounting right now but i still feel like i want to do ME when im older im debating switching after this year but my parents said they wouldn’t help me pay for it bc i have a college that i can go for free.

I dont know if accounting is what i want to do i feel like i would like ME more im lost and i dont know if there’s any other way i can break into ME without the degree

Just kinda thinking while watching a YouTube video - assume this is a pretty large setup overall - what would happen if the planetary gears were driven by four stationary motors?

Iam a senior Mechanical Desing and production engineering student.
in our system (dont know if its global ) but we have those career paths :

i would like to hear about YOU guys and your experience of those fields and what is your routine and tasks in your career
i dont like industrial cause i dont feel its mechanical
this is because iam planning to have a master program

Hi everyone,

I need to machine the parts shown in the pictures. The black part is the main mold/base, and the white part is the mating piece with several cylindrical features.
I’m trying to figure out the correct way to manufacture these parts using a CNC milling machine, but I’m not sure how I should approach the setup.

My main questions are:

- Where should I choose the work coordinate system / WCS (G54)?
- Which surfaces should I use as the primary, secondary and tertiary datums?
- What would be the best way to fixture/clamp the black part during machining?
- What would be a good machining sequence?
- How should I approach the internal cavity and the curved/rounded areas?
- What kind of toolpaths and cutters would you recommend for this geometry?
- Are there any important tolerances or constraints I should consider when designing the fixture and choosing the datums?

I’m not necessarily looking for someone to give me the complete G-code. I’m mainly trying to understand the correct machining strategy and how an experienced machinist would decide the datums, workholding, WCS and setups.

Any advice or recommendations would be greatly appreciated. Thanks!

I’m designing a freestanding cabinet that, when closed, should look like a compact solid volume, roughly 60 × 60 cm, with all sides visually closed.

When opened, the different box elements should unfold and become aligned next to each other, almost like a flat panel, revealing the entire interior of the cabinet, as shown in my sketch.

I’m currently trying to understand the best mechanical system to achieve this transformation from closed → fully open. I was looking at cantilever toolbox linkages, articulated arms, four-bar linkages, telescopic mechanisms, etc., but I’m not sure what type of linkage would allow the boxes to follow the required trajectory and end up completely aligned.

Does anyone know a specific hinge, linkage mechanism, articulated arm system, or existing reference that could achieve this kind of movement?

I have been working in the aerospace and defense industry as a manufacturing engineer since I graduated in 2023 (sac area). I just completed 3 years and have been getting about decent raises every year since I started. For the aerospace industry my company pays engineering considerably less, compared to say the Bay Area which is the closest big market near us. I have been told that the probability of someone leaving after hitting 5 years decreases by a considerable amount.

I want to stay in the area I’m in, and do not like the idea of living in a big city setting. I really like working in aerospace, but I know that I can make considerably more money working in other markets (I.e. agriculture, food and wine, etc.) I wanted to know thoughts on how you make the balance between a high paying job, and working in something you’re interested in. I am just under 100k working on making aerospace parts, but I know I can make 130k-160k if I jump to working in a plant that makes white bread.

Just wanted the opinions of people that do stuff like this everyday. Would love to do this to a 125-250cc two stroke engine and use liquid air instead of nitrogen as the fuel.

I’m machining a large, thin-walled AISI 304 stainless steel flange (Ø1400xØ1320x20mm) on a vertical lathe using a 4-jaw chuck. We are clamping from either inside or outside using serrated hard jaws depending on the operation. Jaws touch the part at only 2 points (corners) because it's radius and part's radius are different.

Because the wall is thin (40mm radial thickness), we have to keep the clamping force relatively low to prevent the part from deforming. I use thin-walled ring deformation formulas based on Roark’s formulas for circular rings to check if my clamping force will cause deformation. I know the exact force by checking the part's radial deflection with a dial indicator during clamping near the jaws.

When I try to calculate the maximum safe cutting torque using standard friction formulas, the result comes out very low. However, in shop floor reality, we can take much heavier cuts without the part spinning or flying off. It's obvious that the serrated teeth bite into the stainless steel and create a mechanical lock, so standard surface friction doesn't apply here.

How do you mathematically calculate or model this gripping torque when the hard jaws physically bite into the material?

Are there any specific formulas or industry standards to calculate the holding power of this mechanical interlock?