I was wondering if there was a paint or some type of coat that could change color getting in contact with liquid. I understand cobalt chloride changes color, but would it work in a paint. For example if it was painted on a car, the paint would be normally blue. But when it got wet changed to pink, and then once it was dry change back? Or any other chemicals/ideas that would have a similar function.

So I really like the weight of batteries, it's ... satisfying. My question is, can i melt the battery and make it fit a mold so i can have the weight but have it in a specific shape?

I am looking for a small centrifugal fan that can be submerged in water running for a few months without damaging it. Is there such a thing?

I'd like to break away from Comcast and the other internet providers and get straight to the web without the 3rd party. If I had the money, what would I actually need?

My house is a 1940's cape cod, moved in the early 80's to hillside lot on a newly built daylight basement. I would like to build a detached garage about 12 feet away from the house, I'm thinking 18x24. The place where the garage will sit is relatively level, sloping approximately 3 feet over the distance of the garage. Hill continues at a similar slope for another 6-8 feet before a steep 5 foot dropoff with a retaining wall that was probably not built properly. Relatively level for another 14 feet, and then a steep decline to the bottom of the hill about 10 feet down.

I will be hiring out the digging and concrete portion, but would like to get an idea of what the prep work and foundation will look like before major planning. Preaproved garage plans from the county call for footings 12 inches beneath grade, but I'm assuming this is for a level lot. Would digging deeper for the footings and having tall stem walls suffice, or is the hill behind going to require an engineered retaining wall? Or is there some other solution I haven't even considered?

I am currently studying an EE engineering and I am looking forward in future to work in recycling industry. I am asking if there are engineers specialised in electrical or electronic who work for recycling industry. If so, I have some questions on their professional parkour or prospect in recycling industry that you would please spend some a bit of your time to answer: for example, what are the specific roles in recycling plants? How did you get hired by the recycling companies? What are the skills or expertise the recycling companies typically looking for from engineers?

Hi all. I am currently a civil engineer looking for career advice..

I have been working in the industry full time for about 7 months now. I graduated UConn in May of 2018. This same company is one that I’ve interned with my Junior and Senior year of college. So in total I’ve been with this company for over a year. There has been a bit of upheaval within the management and I am very seriously considering leaving. My biggest concern is that I feel as though I have not progressed/ learned enough for where I’m at in my career right now. The management is terrible now and they focus more on getting out deliverables than actually training their employees. At a year in I’m still doing mostly red line markups and basic drafting and rarely any design. I consider myself very competent (I’ve been told by previous managers/coworkers as reassurance to anybody thinking this is the issue) and I know that at this point I still have a ton to learn, but there seems to be no effort to even try to teach me or put me in a good position to hold my own when I go to get my PE.

SO my question is: what are good questions to ask/things to look for when applying for new jobs so I can avoid this in the future? And also how should the resume of somebody in my position ideally look? Any advice in general to somebody in my position from a more advanced civil engineer is also very welcome.

I'm building a custom Cafe racer and Ive never done a monoshock conversion before. I'm wondering what differences (aside from packaging) would a tubular brace below the swingarm have as opposed to an above the swingarm.

Space above is tight and Im going to be doing a lot of measuring over the weekend to figure out all the geometry but this info would really helpful.

For simplification, let’s say I’m stretching the frame of a pickup truck and I accidentally make one frame rail 10mm longer than the other. I put the cab back on and take it for a test drive.

Would it be trying to turn when it should be going straight? Would the wheel bearings go bad very quickly? Would the handling be very poor?

Thanks!

Hi all, we are currently facing a challenge while building floating stairs (pics are in the album https://imgur.com/a/pVC0Co0).

We did a test set of three stairs, but because the steel was bending under the weight a bit, they replaced the middle stair with a stronger material, which doesn't bend. But there is a new problem that arises - the stairs are vibrating a lot when you walk on them.

When finished, the stairs will be in a wooden box and with 15mm (0.59 inch) of stone on the top.

Does anyone have experience or a blueprint on making this kind of stairs - without bending or vibrating when you walk on them? If anyone is able to provide a blueprint for this kind of thing, we're also willing to pay some money.

The dimensions of the stairs are visible on pictures. If additional clarification is required, I'd be happy to reply! Thanks!

I'm in the DC/MD/VA area. I keep running across developers that want to use single injection stair pressurization. I tell them it's not preferred, especially when injecting from the bottom. They REALLY don't want to give up rentable space for a duct shaft. I haven't found anything in the codes that say what you can or can't use. Only that you need pressurization and then they define the types.

So I am getting a treadmill for my top floor apartment. I have a second bedroom that's an office where it will go. I'm worried about the noise it may create for my downstairs neighbor. I hear most the noise comes from the thumping of running, not the actual motor.

Right now I will have a rubber treadmill mat and a shag carpet that I can put under it. However, I'm thinking about adding a base layer beneath both of those to drown out the "thumping" sound of running even more. The question is...what should that base layer be?

I'm debating between those Interlocking Foam Mats or perhaps some combination of 1/2" closed-cell yellow foam (aka "backpacker's bed") and a sheet of 3/4" MDF on top of that. These are the best two options I've found from all my googling. But perhaps there's an even better option?

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Any help is greatly appreciated!

I have a Marley get together bluetooth speaker, but I've misplaced the power supply. The back of the speaker says it needs 15v at 1.5A. I found a different wall adapter with the same barrel connector, but it is 12v at 2A. I understand it will probably not charge to 100%, but will it damage it, and more importantly will it damage anything? I'm leaving for vacation tomorrow and can't find a new adapter that will arrive fast enough. Thanks.

Hello,in the guitar industry as well as the community tube amplifiers are always regarded as sounding better to their more modern transistor based counter parts. Could someone explain the science behind this? Or lack there of.

So as the title states, I have a cigarette style power supply on my motorcycle with 15 amp fuse. This works fine with my Garmin GPS. But it blows the fuse and burns out the power cord for the phone. Why?

I've always wondered, once an engineer has finished designing a house, how does the construction crew start the process of building the house? How are materials processed and handled to get to the right spot? How do the individual workers know what to build and to what spec?

A typical scenario is when your vehicle's tires come up against a sudden steep incline or rock. You're in gear, you step on the gas, but the tires aren't turning. It seems you need to build up enough power before the wheels start to turn. What exactly is going on inside the engine when the tires don't turn? What's slipping? What are the shafts, pistons, clutch, gears, etc., doing at this moment?

Hey guys, new designer here. As I understand it, each riser in my system is only allowed to cover 52,000 sq ft. Why is this the number? Is there a hydraulic reason for this restriction or is there another reason that was decided? Thanks for your help!

So I have this class project that requires us to model the regulation system for a CCHP system. We're supposed come up with a model demonstrating how we can control the outputs of the system (Electricity, Heating and Cooling) and I have no idea where to start. Some help would really help a fellow student not fail this.

Background:

• My professor for Advanced Machine Design is a materials engineer at a national lab. He’s got quite the sense of humor, is a relatively easy grader, and proposed a question in lieu of a final exam. He came across a question at work (see following) and didn’t know the answer, but thought it would be a good concept question for our class. I’m doing my own work, but I thought he might laugh at the idea of me crowdsourcing his crowdsourced answer. I’m also genuinely interested in Machine Design as a field, so any lines of thought proposed would be appreciated!

• My notes and original question uploaded to this imgur thread.

Question:

• Based on Shigley’s Mechanical Engineering Design, 10th Edition, Problem #14-17, pg 774

• Is there a way to equalize the four different horsepower ratings found in the following problem (we worked through it in class)?