I am currently taking a CNC machining course and working on exercises. We were assigned this particular exercise, but I can't figure out how to machine both curves because the R25 radius isn't centered. I was thinking of using a G02 command from the bottom-left corner to the top one, but I can't determine the coordinates; I need help figuring out how to define these curves. It is also worth mentioning that I am using a 10mm diameter end mill. I hope someone can guide me.

Edit for clarity:
I am trying to design a mechanism that pushes downward with ~2cm of travel distance and 3-5 pounds of force. At the bottom of the stroke I ideally want the plunger (P1) to completely stop pressing down on the object.

Hopefully the pictures give enough of an idea. There will be a feature in the wall that pops the orange gate in that allows the bottom to fold up. Essentially compressing the spring and then letting it spring back up unimpeded. It's not an actual spring, more like a squishy toy that bounces back to it's original height after being compressed. I don't think my first design will really work though.

Any help would be greatly appreciated!

I wanted to finish my Paddleduck engine. I started it a long time ago and just had half finished parts in a drawer. That didn't feel right. So I got them out dusted off what was there and got to work.

R.I.P John, you were a great inspiration to so many people, and continue to be.

This is a short video of the first run on air. Need to fix up some leaks, finish the timing, packing glands etc. But not too bad for a first run.

For two years now I’ve been watching a lot of model engineering videos. Mostly blondie hacks. I’m getting to the point where I’d really like to build a boiler for myself.
I know I don’t have time or money to set up a machine shop, and I’ve start to come up with ideas about building a boiler out of plumbing parts.
Does anyone know about any projects like this? Does anyone have any better ideas?

Hi everyone! I’m an Industrial Design student currently working on a project involving the design of a medical-grade therapy device, and I’m looking to speak with someone who has an engineering background.

I’m particularly hoping to connect with people experienced in biomedical engineering, mechanical engineering, medical devices, electronics, or product development.

I’d love to get some guidance on things like:

• How engineering constraints influence the form and interaction design of medical devices
• Mechanical/electronic considerations I should be aware of early in the design process
• Material and component selection for a medical-grade product
• Ergonomics and safety considerations
• General considerations around prototyping, testing, and manufacturability

I’m not looking for anyone to disclose confidential information or proprietary designs. I’m mainly hoping to learn from someone who has experience developing or engineering medical/therapy devices.

If you have relevant experience and would be willing to answer a few questions or have a short conversation, I’d really appreciate it!

Thanks!

I’m currently building a Stuart Sirius, but I’m not sure how best to tackle the crankshaft? Any thoughts are greatly appreciated.

Looking for some expert in cell design with experience.

Nickel iron cell koh electrolyte project

Anyone ready to share his adventures in storing electricity

From coil+ bridge rectifier module Lt 4320 + 2 caps+ buck converter 1200 w+ anti reverse back flow ideal diode+ anl fuse 40 a + battery.someone can valide that line or even upgrade it

Anyone joining Model Engineering College CSE this year?

Hello ,I am a mechanical engineer fresh graduate from the Phillipines. I am currently working as a mechanical engineer in a hydroelectric plant under technical support services.I am interested in shifting my career in aviation. I am asking for help on how to achieve this career any books to read or seminars to attend to help me shift to aviation? Can you give an advice on how can I achieve this goal?

On the otherhand if I can't get to aviation industry I am going to stick to hydro but I want to apply abroad ,possibly Switzerland since there are more hydroelectric powerplants there. I am aiming hitachi energy for this however its difficult to get hired .Can you give me insights or advice on how can I achieve this goal?

Hello everyone!

I am new to engineering, and wanted to build the XY kinematics similar to the ones used in CNC or 3D printers ( not sure how is it called ). My main application, however, is moving a weight of about 1-2 kg. In sum with the motor, moving extrusion, and holding part it will be about 5 kg. The total size of this XY frame will be about 800mm x 800mm, but the useful moving distance will be smaller - about 600mm x 540 mm. I plan to use belt driven system as I only focus on speed, and the bar for precision for me is about ±1 mm. I have two main questions:

1. Will 4020 V-slot aluminum extrusion be enough for this job? I ran the calculations ( maybe they are wrong ) and got about 0.5 mm max deflection. Also, should I use anodized or non anodized will also do?
2. Is it possible to achieve 70-80 mm/s speed with such setup? If yes, will 3 NEMA 17 be enough?

I will attach some pictures of the setup, and would appreciate any help from the experts in this chat. Thank you very much!

I want to build a wearable cooling neckband from scratch. My idea is to use PCM (phase change material) chambers to absorb heat, water evaporation for cooling, and 2 small fans to speed up evaporation. I have no electronics background. Is this feasible? What components would I need and how do I get started?

Just some more of the engine

Uses a 12v 80N solenoid and a limit switch in the normally closed position, and is connected directly to a 12v lead acid.

Good afternoon!

I have an Emco Compact 5 lathe (not the CNC version; the manual) whose motor has just failed.

I'm hoping that it's just the starter capacitor (which I can check fairly readily with a multimeter) but there's a good chance that the windings have failed, and no local rewinding company has responded to my inquiries about a repair.

I'm forced to consider a replacement motor; ideally something with a little more power whilst not being so big that it risks damaging the machine or not fitting properly. Unfortunately I'm having trouble finding options that would be appropriate, not knowing a huge amount about electric motors beyond the theory behind them.

The original motor is 500 W, 230 V single-phase.

Can anyone advise re: options for replacement and what specifications I should be looking for? Also any other considerations I should have in mind like power supplies, speed controllers etc.

I live in the UK, so will be running the machine on 230 V single-phase domestic mains supply.

Thanks in advance.

I posted a short video of my Jonas Engine first run a while ago. Since then the engine has been stripped, cleaned, powder coated, polished and reassembled.

Here are a few final pictures. The pictures have come out a bit over saturated, it's a darker shade of red in person.

Building this one has taken a lot, and I have learnt a huge amount getting this one over the line.

On to the next one I guess.

I've been trying to design my own tool, in which I'd like the shaft where the bits are mounted to rotate at high speed like a drill, but also move up and down like a jigsaw. I know a similar mechanism exists in rotary hammers, but it only activates when pressed against something, and rather than moving up and down while rotating, it's more of a vibration. I've searched online for existing mechanical principles, but none of them achieve what I want with just a motor. I'm not very specialized in mechanical engineering, so if the terms I use sound a bit confusing, please clarify. I hope you understand my idea, thank you.

Hi everyone,

I’m currently working on a project where I need to design and analyze an aircraft fuselage section using ANSYS, and I’d like to integrate Python (PyAnsys) into the workflow.

I’m still a beginner with PyAnsys, so I’m looking for guidance on how to get started properly — especially:

• Setting up geometry and meshing with scripts
• Running structural analysis using Python
• Best practices or tutorials for aerospace applications

If anyone has experience with this or can share resources, example scripts, or advice, I’d really appreciate it.

Thanks in advance! 🙏