(Not So) Hobby Machinist

[FromScratch]

Great thread everyone.
I have really enjoyed all the perspectives and experiences!

I decided long ago to NOT make machine work my living.......but now I will wait for retirement to get back to electronics as a hobby.

-brino

I'm retired, and I'm back into electronics too, after an extended absence due to 20 years of self employment and other jobs. I have learned a lot in the last few years. Of course, the inevitable slide away from through-hole components and over to surface mount stuff is not making it any easier, especially for aging eyeballs.

But my oh my, the components you can get these days!!! Op amps for a few bucks that outperform anything available 30 years ago at any price! Power MOSFETs that can handle 250A at 1000V, with on resistances lower than many mechanical switches!! Voltage references for $1.50 with specs like 10V +/- 1mV! 6000 Farad capacitors!! (Takes 4 hours to charge with a 1 amp current!!!) Multi-GHz transistors!

Have fun at DigiKey, the ultimate component search engine! And don't buy anything that looks like it's going down the obsolescence tube unless you are willing to redesign a project the next time you want to knock off another copy. Old stuff disappears fast these days.

Also, try out the EEVBlog forum (I'm on as 'dbctronic'). Lots of very knowledgeable, helpful folk, and far more threads than you'll ever have time to read. Just like here!!

 

[C-Bag]

I'm retired, and I'm back into electronics too, after an extended absence due to 20 years of self employment and other jobs. I have learned a lot in the last few years. Of course, the inevitable slide away from through-hole components and over to surface mount stuff is not making it any easier, especially for aging eyeballs.

But my oh my, the components you can get these days!!! Op amps for a few bucks that outperform anything available 30 years ago at any price! Power MOSFETs that can handle 250A at 1000V, with on resistances lower than many mechanical switches!! Voltage references for $1.50 with specs like 10V +/- 1mV! 6000 Farad capacitors!! (Takes 4 hours to charge with a 1 amp current!!!) Multi-GHz transistors!

Have fun at DigiKey, the ultimate component search engine! And don't buy anything that looks like it's going down the obsolescence tube unless you are willing to redesign a project the next time you want to knock off another copy. Old stuff disappears fast these days.

Also, try out the EEVBlog forum (I'm on as 'dbctronic'). Lots of very knowledgeable, helpful folk, and far more threads than you'll ever have time to read. Just like here!!

Wish you electronics guys would get together and make fixes for all these dead or dying super cheap now CNC centers. Maybe there is already folks fixing them, dunno.

 

[ttabbal]

CNCs are deceptively simple. You can usually run the existing drivers with standard stepper controller signals. So you just lose the main controller and replace it with Mach or linuxcnc. If not, replace the motors and controllers. Tool changers and probes add complexity, but nothing you can't overcome. Particularly if it's even a little operational and you know your way around an oscilloscope. If I find one cheap enough, with decent mechanics, I might give it a go. The trick is that the ways are often worn and it's not worth the effort to fix the motion contol on a clapped out machine.

 

[addertooth]

FromScratch,
Like you I made my living in Electronics design and instrument calibration for decades (after the Machining industry collapsed). Then I noticed that people who did Computer networks had to know half as much, but got paid much more. So, I switched to Network test engineering and design. We have some fresh folks with EE degrees which I work with, it is a bit sad. I never imagined that EE courses would be so dumbed down that they would turn out folks with such soft skill sets. Old timers (like us), are the "scary old men" of the industry these days. We don't need advanced cad-ware to design or debug systems. They look at us like we are some kind of mutant species today.

Also like you, I am amazed at the components available today. There are now single-chip computers (which will run on a hearing aid battery), which would run circles around any of the 8086, Z80 and 6502 based computers I designed decades ago. Like you, I would have killed for op-amps that had root mean square noise figures available today. I remember buying Burr-Brown amplifier modules at $200 a piece (1980s dollars), to get my noise factors lower on instrumentation amplifiers, they compare sadly to many offerings today which cost 79 cents.

I suspect that many of us here would be considered renaissance men, due to our breadth and depth of skills (which have been largely allowed to disappear from society). I suspect that many of us have children, who believe our hobbies are "unfathomable".

 

[ChandlerJPerry]

You electronics guys definitely practice a black art. I would consider myself competent at basic wiring tasks and maybe even simple circuit design when it comes to basic components like switches and resistors. But concepts like impedance, capacitance, etc and components like mosfets, ICs, and capacitors always make me feel like a crazy person whenever I try to learn more about them . Granted most of my hobbies don't require any electronics knowledge, but seeing the cool things you wizards can design is definitely awe inspiring when compared to my own knowledge and ability.

 

[kb58]

I did EE for 20yrs, then SW for another 10, now in Field Support for yet another 10, which requires knowing everything about everything. And on the side, I like building stuff, cars, fish pond systems, telescopes, etc. It's nice to have diversity, but as for doing something you like as a career, not so much. That said, I wrote and sell a book on building a mid-engine sports car, which partially funds the car. The good thing about that is that it's completely hands-off so I don't have to deal with customers, and so that's right back to the advice on keeping interactions with customers separate from your otherwise enjoyable hobbies.

 

[FromScratch]

FromScratch,
Like you I made my living in Electronics design and instrument calibration for decades (after the Machining industry collapsed). to disappear from society). I suspect that many of us have children, who believe our hobbies are "unfathomable".

Actually, I was self employed as a tech writer for a few years, then did home repairs for almost 20. I'm self taught in electronics, and my design tools are a pocket calculator and, at times, a spreadsheet. And good ol' pen and paper, followed up with a word processor. But I started in electronics at age 11, and learned from textbooks, as well as the GE tube manual. Started programming with 80 column cards (FORTRAN). Nowadays, online articles and datasheets are the mainstay, and if I write code, it's Python.

It's hard to find anybody nearby who shares my interests. Really aghast to hear that even EE grads are so lame, with all of the fantastic educational technology available today. We oldtimers all would have killed to have finite element design software, circuit design systems, CAD, and the Net!!!

We've got to keep our knowledge alive. I'm doing my bit in really mastering magnetics. I want to write some documents explaining it the way I've always known it could be, but never is. To newcomers, it seems mystical and abstract, but it's really just poorly documented, the same way over and over.

 

[Nutfarmer]

I just wish the electric engineers would quit with the computer controls when a simple switch would work just fine. We must have the bottom of the barrel engineers designing farm equipment. I just spent two days in an air conditioning system in a harvester that was computer controlled what a mess. What ever happened to KISS.

 

[ttabbal]

I just wish the electric engineers would quit with the computer controls when a simple switch would work just fine. We must have the bottom of the barrel engineers designing farm equipment. I just spent two days in an air conditioning system in a harvester that was computer controlled what a mess. What ever happened to KISS.

One computer costs less than a bunch of mechanical switches. It's at least half the fault of the bean counters.

 

[addertooth]

NutFarmer,
I can't help but agree with Ttbbal. A vehicle AC system will typically have to power an AC compressor clutch, and a fan at multiple speeds (typically through Pulse Width Modulation PWM). A higher end system will need to sense low pressure on the suction side, as well as a high head pressure/heat. These things can be done purely mechanically, but considering you already have (on a modern piece of equipment), an Electronic Control Unit ECU (for the Engine), it constitutes less of a cost to add a couple of inputs/outputs to the ECU. This also allows any switches on the dash to be inexpensive low-current switches for signaling the ECU, as versus more expensive high-current switches which have fan power ran through them and using resister packs to Slow the fan when it is in the lower speed positions.

Bean Counters certainly *can* be tyrants. I bought a used car once, which someone had become frustrated with the wiring. The previous owner had added two big toggle switches on the dash. One turned on the AC compressor clutch, and the other flipped power onto the fan at full blast. It did work, but it was a real pain to restore back to factory configuration.