Test Equipment Anonymous (TEA) group therapy thread

[0culus]

We're close to overflowing a 16 bit integer with the number of replies in this thread. 

[Cerebus]

On the subject of joining bits of metal, I've got some small awkward brazes that need doing. All the clamps I have are way too big and awkward so i ordered some mini welding clamps that arrived today. They are the cutest little things:



I do not have big hands, I take a size 7 1/2 glove, so those things are tiny. Four for a tenner.

[BU508A]

There was recently this discussion about Ultrasonic cleaner.
Now I have bought one.
A Emag EMMI 40HC Ultraschallreiniger 250W 4l for 384,05 Euro.
Usually they start at 433,- Euro.



And I've ordered together this cleaning liquid concentrate: Emag EM-303

[Specmaster]

Yeah given up on that idea already and bought a TTi TG320 function generator. 

Edit: paid slightly over three going rate but I need one next week and I don’t want to pay 2.5-3x for something for casual analogue use and some TTL stuff. Has built in counter and digital readout though so I’m good.

Just need another decent DMM and I’m good to go on next project 

Nice, but I can't help but think you could have done better buying 2 units instead of 1. like this https://www.ebay.co.uk/itm/TTI-TF830-Frequency-Counter-and-Feeltech-FY3200S-24-MHz-Function-Generator/233654297583 for instance and keep an eye out for a TTi TG120 20Mhz function generator, I paid £40 2 years ago. 

[tggzzz]

As a software guy I approve of the use of glue when only a weld will suffice 

What, when you could use string from 15 different sources, all tied end to end into a cat's cradle and then use that to make the fixture? That's what I've learned from modern IT practice.

Not far off, except that there are companies that make products that are "intelligent string" interconnecting other vaguely compatable products. Seriously.

The "intelligence" is protocol conversion plus filtering plus mux/demux, with a few simple FSMs thrown in to control it.

[Cerebus]

There was recently this discussion about Ultrasonic cleaner.
Now I have bought one.
A Emag EMMI 40HC Ultraschallreiniger 250W 4l for 384,05 Euro.
Usually they start at 433,- Euro.

And this is exactly why I own a crappy 750ml one designed, basically, for cleaning jewellery. I think I paid £20 for it. For the money is does a surprisingly good job. I always promised myself it was to "get by on" until I could afford a decent one/found a real bargain. That was about 5 years ago. I haven't yet built up the courage to dive into my wallet, fight off the giant moths dwelling in there, and stump up for a 'proper one'.

[BU508A]

As a software guy I approve of the use of glue when only a weld will suffice 

What, when you could use string from 15 different sources, all tied end to end into a cat's cradle and then use that to make the fixture? That's what I've learned from modern IT practice.

Not far off, except that there are companies that make products that are "intelligent string" interconnecting other vaguely compatable products. Seriously.

The "intelligence" is protocol conversion plus filtering plus mux/demux, with a few simple FSMs thrown in to control it.

How is this dude involved here?   

[Cerebus]

I want to know what Med's doing with cups from the Betty Ford clinic. Med, is there something you want to tell us? 

[Specmaster]

There was recently this discussion about Ultrasonic cleaner.
Now I have bought one.
A Emag EMMI 40HC Ultraschallreiniger 250W 4l for 384,05 Euro.
Usually they start at 433,- Euro.



And I've ordered together this cleaning liquid concentrate: Emag EM-303

Yep, that would be me then, The one I thought I was buying was a 3L one and instead the seller sent me a 2L, tank is not large enough to take much more than a watch and other jewellery, now I'm embroiled in a battle with the seller via eBay, thank goodness I went through them, it's a long ongoing saga. Basically the seller (Chinese company with a UK warehouse) used 12 photos of a 3L unit with a tank size of 240mm long and sent me a 2L one with a tank length of 150mm. They want me to return the 2L at my cost and then they will give me a full refund. Ebay and myself are saying, no, send me prepaid returns label first and also I don't want a refund, I want the 3L one that I thought I was getting.

Ebay have now giving them a ultimatum, send me a prepaid label within 5 days or they will find in my favour, refund me and I get to keep this 2L one, so lets see what happens now. 

[Cerebus]

How is this dude involved here?   

If you don't fall down and worship him in exactly the right way, then the spaghetti code in your computer programs won't work.

[Cerebus]

Ebay have now giving them a ultimatum, send me a prepaid label within 5 days or they will find in my favour, refund me and I get to keep this 2L one, so lets see what happens now. 

OK, in the sweepstake I take "Specmaster gets a free 2L one". I presume that if I win I get the classic Stan Lee prize?

[bd139]

Yeah given up on that idea already and bought a TTi TG320 function generator. 

Edit: paid slightly over three going rate but I need one next week and I don’t want to pay 2.5-3x for something for casual analogue use and some TTL stuff. Has built in counter and digital readout though so I’m good.

Just need another decent DMM and I’m good to go on next project 

Nice, but I can't help but think you could have done better buying 2 units instead of 1. like this https://www.ebay.co.uk/itm/TTI-TF830-Frequency-Counter-and-Feeltech-FY3200S-24-MHz-Function-Generator/233654297583 for instance and keep an eye out for a TTi TG120 20Mhz function generator, I paid £40 2 years ago. 

Had that on the watch list.

I really want some less drive by wire instruments if I’m honest. Much nicer sweeping filter phase and response by hand then picking the frequency off the screen. Switching encoder resolution is a pain in the arse. Also the more expensive AWGs can’t hit 20v peak to peak which I need to have to blow outside the common mode input range of a couple of things. The cheap ones say they can but you don’t know where the distortion comes from 

As for the feeltech. I don’t trust putting it near decent quality semiconductors and opamps. 90v float is risky. Want my shit grounded.

[med6753]

I want to know what Med's doing with cups from the Betty Ford clinic. Med, is there something you want to tell us? 

I need to cut down on the IPA. 

[med6753]

As for the feeltech. I don’t trust putting it near decent quality semiconductors and opamps. 90v float is risky. Want my shit grounded.

I fixed mine. It's grounded. Easy to accomplish and safe.

[Specmaster]

Ebay have now giving them a ultimatum, send me a prepaid label within 5 days or they will find in my favour, refund me and I get to keep this 2L one, so lets see what happens now. 

OK, in the sweepstake I take "Specmaster gets a free 2L one". I presume that if I win I get the classic Stan Lee prize?

If you mean the kudos of being right, yep

[bd139]

As for the feeltech. I don’t trust putting it near decent quality semiconductors and opamps. 90v float is risky. Want my shit grounded.

I fixed mine. It's grounded. Easy to accomplish and safe.

It probably is but I have no desire to fix design errors in kit I buy really. Kit I make, yes

[Specmaster]

As for the feeltech. I don’t trust putting it near decent quality semiconductors and opamps. 90v float is risky. Want my shit grounded.

I fixed mine. It's grounded. Easy to accomplish and safe.

I was just going to say that but you beat me to it. Just struck me that it seemed foolish to go with 3MHz when you can get at least 20Mhz for similar money, even if you only working with audio, now, but in the future? A recipe for more upheaval flipping and sourcing all the time.

[Cerebus]

Ebay have now giving them a ultimatum, send me a prepaid label within 5 days or they will find in my favour, refund me and I get to keep this 2L one, so lets see what happens now. 

OK, in the sweepstake I take "Specmaster gets a free 2L one". I presume that if I win I get the classic Stan Lee prize?

If you mean the kudos of being right, yep

https://en.wikipedia.org/wiki/Marvel_No-Prize

[bd139]

As for the feeltech. I don’t trust putting it near decent quality semiconductors and opamps. 90v float is risky. Want my shit grounded.

I fixed mine. It's grounded. Easy to accomplish and safe.

I was just going to say that but you beat me to it. Just struck me that it seemed foolish to go with 3MHz when you can get at least 20Mhz for similar money, even if you only working with audio, now, but in the future? A recipe for more upheaval flipping and sourcing all the time.

If I need above 5MHz, an AWG is better as I'm probably going to need better frequency stability at higher frequencies. But I did an analysis of all the use cases I had over the last few years that weren't RF and they were all crystal fundamental frequencies for clocking something (microcontrollers and CPUs/counters). Going back over 40 projects, I need around 300KHz max really so a 20dB ceiling is pretty much ok 

If I was going to buy an AWG I'd buy an SDG1032X minimally which is way over 3x the cost of this box.

Edit: also this thing will pump out ramped waveforms faster than an AWG for linearity / barn roofing tests.

[Specmaster]

Had that on the watch list.

I really want some less drive by wire instruments if I’m honest. Much nicer sweeping filter phase and response by hand then picking the frequency off the screen. Switching encoder resolution is a pain in the arse. Also the more expensive AWGs can’t hit 20v peak to peak which I need to have to blow outside the common mode input range of a couple of things. The cheap ones say they can but you don’t know where the distortion comes from 

The TG120 is virtually the same item as you have, no screen or encoders to work with. Has preset bands and a variable control and will provide you with the require 20VPP, I love using mine, my feeltech equivalent is redundant.   

[bd139]

Yeah that's a good option and similar in the brain department but this one has 120MHz 7-digit counter, digital peak-peak and offset voltage readout, 600 ohm output etc built in which is valuable because that means I don't need a counter or to measure it on a scope as it goes in (which is fine but an extra step I CBA with). Also means it'll do a half decent job as a counter if i need it which isn't some horrible Rigol implementation (kill me with a spoon if i have to use another counter built into an AWG)

[Specmaster]

Yeah, all I do is to run the TG120 into my TF930 via a T adaptor and onto the device I'm working on if I need to know the precise frequency and if I need the amplitude check it with meter or a scope to give myself maximum capability with minimal outlay, because like you, I'm a cheapskate and the only RF I ever get involved with is broadcast band radios, repairing them, not building them so all I need to cover them is a RF signal gen with AM and FM modulation which I also have, otherwise I'm either dabbling in audio or meters of one kind or another and just maybe the odd oscilloscope. TBH though, these days I'm pretty well covered with my TDS210, PM3390B and my little baby scope GOS310. Even my Heathkit scope calibrator these days is used more as a sanity check on my DMM's for voltage 100V and below 1V

[mnementh]

Whatever dude. You can armchair QB this one all you want. I know about aluminum and the speed with which it oxidizes; and that you need to use a SS brush. Even between changing work angles on the work. And you really wanna store that brush so it doesn't get contaminated by other crap in the shop, too. They make rod for stick welding aluminum, and you can also use it as filler for DC TIG as long as the metal is thin enough.  I know it's the wrong way to do it, and gets no penetration; hence sheet metal and tube. Again... you're talking CAN'T vs best practice.

I don't like to stick weld with a coathanger either but I assure you it CAN be done, as I've done it when I had to. Not pretty, but welded nonetheless.

For fuck's SAKE man.

None of this REALLY matters... even if I CAN'T do aluminum with that little buzzbox I can still do ferrous; both stick and TIG. I could even do AL MIG with it if I wanted to spend the money on a spoolgun. There are plenty of applications here; $50 is nothing to throw at it. I spent more than that on pizza & wings for lunch.

mnem
 

Y'know Mnem. It would be nice if just once in a while you admitted that you don't know everything about all things mechanical and admit that sometimes you've got it wrong. All this flows from me pointing out that it was a DC only box, and that's not suitable for TIG welding Aluminium. Anyone who knew their way around TIG would have gone "Good catch, thanks".

You however, seem to blow up like this every time someone brings up something that points out the limits of your knowledge and you start getting squirrelly and argumentative. On this one, everything I have ever learned about this from the guys who do it for a living, and from the guys who do it for a hobby, and from my welding textbooks says you're wrong. Nothing says it with as much clarity as much as that screen grab of a DCEN weld in Aluminium. That one could bodge it, or even weld with a coathanger is just distraction. It's not a question of "best practice" versus "the possible", it wasn't even a question until you made it one because all the rest of the world says "AC for TIG welding on Aluminium" and for some reason you choose to disagree with the rest of the world.

That you have held a welding torch and used it a few times does not make you the expert who's competent to disagree with all the acknowledged expertise from the field, and does not excuse you from accusing someone of being an "armchair QB" because they disagree with you based on that pool of knowledge. Not that it counts for anything, but I suspect that I made my first weld before you were born (MMA on angle iron, frame for the two Villiers 2 stroke motors from two scrapped 'invalid carriages*' for a hovercraft that I was building with my father, circa 1970).

* Yes, the Ministry of Health really did hand out these deathtraps to disabled people right up until some time in the 1970s:      That is a superior specimen. They were a common sight in my youth and were much rattier looking than that.

Y'know C... all this doesn't change the fact that I've DONE IT. I really get tired of having to defend what people say CAN'T be done... when I did it decades ago. It may not have been the RIGHT way to do it, but I DID it.

I DON'T KNOW EVERYTHING. There are libraries full of books full of things I don't fucking know. I've done a LOT of welding... even for a living for a while... but I for gawd's sake don't know even a fraction of everything there is to know about welding. But I know I CAN TIG aluminum with DC, I've done it.

But you know what... don't take MY word for it.

https://weldingmastermind.com/11-tips-for-tig-welding-aluminum-with-dc/

See? I was wrong... this article sez DC for AL is best when you need deep penetration. That probably means I was running my TIG work too cold because I was afraid of blow-thru with the tubing/clip angles I was trying to weld. OTOH, I remember it felt like I had to crank it up 3x as high as it should be to even start my arc, and even then I couldn't see the puddle until after the flux from the filler rod started to curl away from the work. 

Or maybe this one...

https://www.thefabricator.com/thewelder/article/aluminumwelding/aluminum-workshop-aluminum-tig-with-dcen

or this one, which feels a lot like MY experience...

http://hildstrom.com/projects/dctigaluminumflux/index.html

or maybe this video...



That sez the same thing: DC for penetration. Oh, and duh... no wonder I had to use the stick welding rod as filler: I'm about positive I was using the wrong gas, Argon, and entirely possible the TIG filler rod I originally tried to use was the wrong alloy.

But NO C... the WHOLE WORLD does not say "never use DC TIG for aluminum". Just that in most cases, it's not the BEST choice.

I never said it was the BEST choice... or even a good choice... just that I knew it could be done. Just like I know you can weld heavy cast iron with a old Lincoln 225 welder and 6013 rod, just like I know you can braze aluminum treadplate with a MAPP torch if you get the right rod, just like I know you can cut plate steel with a brazing torch. All of which I have done for the same reason: the work needed to be done, but the right tools simply weren't available at the time or the job at hand didn't justify spending the money on the right tools for the job.

This short list was NOT me digging through the darkest corners of the internet. This was literally the first few hits. There's lots more, all saying pretty much the same thing.

I don't care if that little box is the right thing for the job. When I get one, I'll mod it for TIG use. And if I NEED to weld Aluminum, I'll do the same thing I've always done... use what I have at hand, or mod it and make what I need and get the job done. Just like I've always done. Just like I did back then, by trial and error.

I hope I've admitted I don't know everything and that I was wrong enough times here that maybe you noticed; it's not the first time and it certainly won't be the last. You have no idea how many times I've said these words to my son: Don't look at me like I know everything; all I really know is just about enough to guess at how little I really know.

NOW... can we please put this to rest?

mnem
smeesh.

[mnementh]

On the subject of joining bits of metal, I've got some small awkward brazes that need doing. All the clamps I have are way too big and awkward so i ordered some mini welding clamps that arrived today.

They are the cutest little things:      I do not have big hands, I take a size 7 1/2 glove, so those things are tiny. Four for a tenner.

I give you a week before every one of them has the spring burned out of it. 

mnem
"Why are my magnet clamps stuck to the ceiling again?"

[niner_007]