Oh, I can solder but would rather not bother. I just need any wire welder that I don't have to build.
- Status
Oh, I can solder but would rather not bother. I just need any wire welder that I don't have to build.
Mad - the cheapest OP AMP to fit those specs I could find was 14 bucks. wouldn't happen to know where there is one that isn't so expensive? thanks in advance.
There are thousands of types that have very low input bias currents and correspondingly high differential input impedance.
Here's one I picked basically at random (from thousands of part numbers that meet the criteria) IRequest
Input bias is 1pA and differential impedance 10^13. It costs 29 cents.
If you want to splurge (lol) and spend $1.64, here's one with extremely low input bias current in a dip package. IRequest
Input impedance is specified at greater than 1 Teraohm. Input bias doesnt get much lower; it's basically able to look for nothing and find it lol. This one might be worth playing with due to its packaging and input voltage range. Also a typical application includes sample & hold, which is basically what you're building.
Well no, not really. There are some (semi) commercial welders available but I don't know of a US shop carrying them.
There's the TSAF and TSAF VRD from Greece and the Zapper and Zapper v2 from the UK
The main reason I'm going to build one is I want it to have all the extra features like an Ohm meter and Volt meter and there's only 1 like that available but it's not how I want it to be.
If you take some time to plow through the last 30 pages or so, there's also a member who's offereing his welder because he's not using it anymore.
A picture is worth a thousand words. Yo Han, pardon my butchery of your schematic, but try this -
Incidentally, C1 in the original drawing is a suppressor cap to mitigate sparks on the discharge switch. In my case, a filter capacitor isn't needed on the output of the bridge, but with the LM2577 it's probably a good idea.
Hello - another newbie here~! I have read every post up to #1257 (going to sleep will continue tomorrow), and have read the instructable pages as well. My problem is (duh) I do not even know how to solder or read diagrams. But I find this very interesting, and would like to learn both the skills needed, and to actually build a working model.
My question is, would someone be willing to either list what some good basic tools/components one ought to have, and perhaps a "soldering for dummies" type book? I do not know what 'flux' is, or the difference in different types of solder - I mean really basic info - self-teaching works great, 'cept for the stuff you don't know that you don't know - if you know what I mean?
If I could wish, it would be for a final good parts list, a diagram - plus how to learn to read it, and what tools/items I should have to be able to build it. - Yep! All this at age 51 - not an area of any interest until lately - many seriously cool projects I've been seeing.
Sorry for the long, boring newb post!
OK. Here's my latest version. It's designed around the way I work, the methodology I use when welding and to minimize taking pre-built modules apart. I want to be able to "fine tune" the voltage and capacitance depending on the wire sizes in use, from 36 gauge on down to 28 gauge. For example welding a 36ga wire to a 30ga wire can get a little tricky. The toughest part has been extending, physically, the trim pot on the LM2587 to allow voltage adjustment from outside the project box.
Keep in mind that this version can produce up to 60 volts at the welding connections. This is substantially higher than many other welders in this thread and could produce a potentially dangerous shock to the user. Use with caution!
As far as soldering techniques are concerned, there a lots of videos on YouTube showing how to solder. Just use a decent quality electronic solder that already contains flux. Actual construction can be literally "point to point" wiring, built on a piece of perf board or even on an etched circuit board. In terms of reading the diagram, if there is a dot where two lines, wires, cross that means there is a connection. No dot means no connection.
(to be read at double speed)
Just my opinion, worth what you're paying for it. Your results and mileage may vary. No warranty or guarantee is expressed or implied. Proceed at your own risk. The end user agrees to hold the poster harmless and without liability. I am not a doctor, scientist, chemist or physicist and hold no academic degrees, nor do I play any of them on TV.
Keep in mind that this version can produce up to 60 volts at the welding connections. This is substantially higher than many other welders in this thread and could produce a potentially dangerous shock to the user. Use with caution!
As far as soldering techniques are concerned, there a lots of videos on YouTube showing how to solder. Just use a decent quality electronic solder that already contains flux. Actual construction can be literally "point to point" wiring, built on a piece of perf board or even on an etched circuit board. In terms of reading the diagram, if there is a dot where two lines, wires, cross that means there is a connection. No dot means no connection.
(to be read at double speed)
Just my opinion, worth what you're paying for it. Your results and mileage may vary. No warranty or guarantee is expressed or implied. Proceed at your own risk. The end user agrees to hold the poster harmless and without liability. I am not a doctor, scientist, chemist or physicist and hold no academic degrees, nor do I play any of them on TV.
Last edited:
Post 1316 has my final schematic + links to the parts on eBay.
You should just read some beginner's guides on electronics. I have no background in electrionics as well but I managed to figure this out with the help of awsum140.
I'm not sure this is what you want though. A lot of people wouldn't need a resistance meter built in.
Thanks, Yo Han. I'll let you know how it actually works once it's built. I'm still waiting for resistors to come in.
I'm also waiting for parts. It's great that you can get them from China for such a low price but it can take weeks before you can finally finish a project...
PS: I see you've put a 1N4001 on the 2587 output (D1). Would it make sense if I put one there as well?
Last edited:
My eyes died for the night before I saw your great post with all the info
And actually, I *like* the idea of having the built in meter!
And, yes, I think I need to spend some time with some basic reading, and probably gaining some practical knowledge in soldering as well. This thread has made for a lot of interesting reading, and I do hope you will post your results of actual builds (both you and awsum140).
Yo Han, I put that diode in as a "best practice" feature. In reality, it's probably not needed at all.
Oh by the way, I think you forgot to add a momentary switch in front of R2
And I was thinking, using one of the welding terminals for measuring resistance sounds a bit scary with this setup. When accidentally choosing the wrong terminal: Zap! Bye bye resistance meter...
Perhaps not a problem for you but I prefer a fool proof design. Why not add a second banana jack for measuring?
And I was thinking, using one of the welding terminals for measuring resistance sounds a bit scary with this setup. When accidentally choosing the wrong terminal: Zap! Bye bye resistance meter...
Perhaps not a problem for you but I prefer a fool proof design. Why not add a second banana jack for measuring?
Last edited:
I don't need the momentary switch, the LM 2587 will be online all the time which is why I upped the power rating and resistance of the surge resistor and the discharge resistor. I don't want to overload the LM2587 but still allow voltage adjustment directly from it. That will keep the voltage "rock solid" with no droop from leakage in the capacitors.
As far as the ohm meter is concerned...Resistance readings are taken from a completed weld, negative terminal, to the resistance wire to get the right resistance. After both "zero" resistance wires are welded on it can safely be taken. The LEDs are an added "safety" measure to make sure, by visual indication, the positive electrode is always identified. No design is ever fool proof, us fools are very imaginative, LOL.
As far as the ohm meter is concerned...Resistance readings are taken from a completed weld, negative terminal, to the resistance wire to get the right resistance. After both "zero" resistance wires are welded on it can safely be taken. The LEDs are an added "safety" measure to make sure, by visual indication, the positive electrode is always identified. No design is ever fool proof, us fools are very imaginative, LOL.
- Status
Similar threads
