Interesting the first comment....QuoteI like to solder all my lugs on for an even better connection. And in the example at the end where you cut through the 4 - 0 lug, you chose a location where it had not been crimped thereby showing an uncrimped gap inside. Not a nice demonstration. Solder has always been superior to crimp, throughout the history of cable lug use. Not sure where you went to school but we actually tested crimped vs soldered connections for resistance and noticed failures in current draw tests. The solder, when done correctly always produced better results than crimps when done correctly. In most applications, either will suffice. However, for pure results solder wins. Silver based solder is 5% more conductive than copper (copper 100%, silver 105% using copper as the standard conductor). Heating wire tends to distort the insulator so care must be used. I like to use a wet rag to cover the insulation near the end or an cooling paste which is available from most HVAC wholesalers. Silver requires a bit more heat than propane, though so most opt for the crimp. We're talking about the purest method here...in real life and in most situations the crimp will suffice. Its important to know the composition of the lug being used as well. Some are made of aluminum while some are copper and other's copper with a tinned coating. Best to choose one with copper, either bare or tinned, since aluminum tends to oxidize over time which creates friction within the lug. I've seen 'em glowing red like a toaster element from bad connection. I got about 50 years experience in this subject.
Talking of ginger and white cats. About 30 minutes ago the living room curtains twitched and about five feet off the ground a furry ginger and white face poked through them. We're not on the ground floor, and we don't have a ginger and white cat. Window now shut to keep the furry burglar out.
See, now that was a missed opportunity - you could have had a ginger and white cat, but you blew it!
They make excellent lab assistants.
-Pat
Madam of the furry variety, not Madam of the human variety
Forgive the dumb question, but why not just put that tool in a vice to squeeze it smoothly instead of hammering it ?!
The smooth progressive action of the vice would be kind to the lug wouldn't it.
I mean a real big/full size garage vice of course, not the tiny vice we use in the lab, that goes without saying !
Interesting the first comment....QuoteI like to solder all my lugs on for an even better connection. And in the example at the end where you cut through the 4 - 0 lug, you chose a location where it had not been crimped thereby showing an uncrimped gap inside. Not a nice demonstration. Solder has always been superior to crimp, throughout the history of cable lug use. Not sure where you went to school but we actually tested crimped vs soldered connections for resistance and noticed failures in current draw tests. The solder, when done correctly always produced better results than crimps when done correctly. In most applications, either will suffice. However, for pure results solder wins. Silver based solder is 5% more conductive than copper (copper 100%, silver 105% using copper as the standard conductor). Heating wire tends to distort the insulator so care must be used. I like to use a wet rag to cover the insulation near the end or an cooling paste which is available from most HVAC wholesalers. Silver requires a bit more heat than propane, though so most opt for the crimp. We're talking about the purest method here...in real life and in most situations the crimp will suffice. Its important to know the composition of the lug being used as well. Some are made of aluminum while some are copper and other's copper with a tinned coating. Best to choose one with copper, either bare or tinned, since aluminum tends to oxidize over time which creates friction within the lug. I've seen 'em glowing red like a toaster element from bad connection. I got about 50 years experience in this subject.
Ok, I just got around to watching the video, and there are three points I care to make.
1. That fly was the star of the show, it trolled the **** out of him!
2. He didn't crimp the lug correctly, and it wasn't because it was a cheap tool. You do NOT crimp to the tip of the wire, you only ever crimp BEHIND it. This is so the conductor forms a wedge in front of the crimp, preventing any realistic possibility of the cable pulling out of the crimp.
3. That was a crimp only lug. The ones that are intended for crimp or solder have a relief hole at the front, like the second one he sectioned.
Talking of ginger and white cats. About 30 minutes ago the living room curtains twitched and about five feet off the ground a furry ginger and white face poked through them. We're not on the ground floor, and we don't have a ginger and white cat. Window now shut to keep the furry burglar out.
Had that with a tabby cat here a few months back. Was just sitting at the desk and it came and brushed my leg. I crapped myself as we don’t have a cat . I shovelled it back out of the window it came from.
As much as I hate cats, the poor bugger was hit by a car a couple of weeks back and didn’t make it
Forgive the dumb question, but why not just put that tool in a vice to squeeze it smoothly instead of hammering it ?!
The smooth progressive action of the vice would be kind to the lug wouldn't it.
I mean a real big/full size garage vice of course, not the tiny vice we use in the lab, that goes without saying !
Because of how they work. To correctly crimp any crimp, you need to squeeze evenly from all sides at once. This kind of crimper was devised as a half-measure, to get a maybe-OK half-assed crimp without spending the big bucks on a proper industrial crimper. The core problem is that the action doesn't only compress, but rather is a wedge that acts to split as much as it does to compress.
Because of this, it relies on the integral strength of the lug to "get away with doing it wrong". With the race to the bottom in everything, including making things like this of the thinnest material we can get away with, you can't count on that anymore.
mnem
Just say "No, thank you" to crappy crimpers, no matter how cheap or expensive they are.
Interesting the first comment....QuoteI like to solder all my lugs on for an even better connection. And in the example at the end where you cut through the 4 - 0 lug, you chose a location where it had not been crimped thereby showing an uncrimped gap inside. Not a nice demonstration. Solder has always been superior to crimp, throughout the history of cable lug use. Not sure where you went to school but we actually tested crimped vs soldered connections for resistance and noticed failures in current draw tests. The solder, when done correctly always produced better results than crimps when done correctly. In most applications, either will suffice. However, for pure results solder wins. Silver based solder is 5% more conductive than copper (copper 100%, silver 105% using copper as the standard conductor). Heating wire tends to distort the insulator so care must be used. I like to use a wet rag to cover the insulation near the end or an cooling paste which is available from most HVAC wholesalers. Silver requires a bit more heat than propane, though so most opt for the crimp. We're talking about the purest method here...in real life and in most situations the crimp will suffice. Its important to know the composition of the lug being used as well. Some are made of aluminum while some are copper and other's copper with a tinned coating. Best to choose one with copper, either bare or tinned, since aluminum tends to oxidize over time which creates friction within the lug. I've seen 'em glowing red like a toaster element from bad connection. I got about 50 years experience in this subject.
Ok, I just got around to watching the video, and there are three points I care to make.
1. That fly was the star of the show, it trolled the **** out of him!
2. He didn't crimp the lug correctly, and it wasn't because it was a cheap tool. You do NOT crimp to the tip of the wire, you only ever crimp BEHIND it. This is so the conductor forms a wedge in front of the crimp, preventing any realistic possibility of the cable pulling out of the crimp.
3. That was a crimp only lug. The ones that are intended for crimp or solder have a relief hole at the front, like the second one he sectioned.
IMO the amount of cable he stripped would go well into the shoulder of the lug, so beyond where he made the first crimp, as you suggest it should be.
BUT... if you're going to double-crimp as he did (there are arguments for and against... not gonna get into that here) you should do the first crimp at the END of the lug, not at the shoulder. This ensures you have the wedge/plug you're trying to make correctly formed BEFORE you make the second crimp.
You should try to avoid having your second crimp overlap the first; this ensures that the wedge/plug you're talking about forms BETWEEN the two crimps, and the second crimp really is only "for good measure".
mnem
Oh, and right on aboot the fly... that made for some good cinema there.
Talking of ginger and white cats. About 30 minutes ago the living room curtains twitched and about five feet off the ground a furry ginger and white face poked through them. We're not on the ground floor, and we don't have a ginger and white cat. Window now shut to keep the furry burglar out.
Had that with a tabby cat here a few months back. Was just sitting at the desk and it came and brushed my leg. I crapped myself as we don’t have a cat . I shovelled it back out of the window it came from.
As much as I hate cats, the poor bugger was hit by a car a couple of weeks back and didn’t make it
Better watch out bd... we might start thinking you actually have a soul or summat... you know, something left that hasn't been eaten by all your redheads...
mnem
Interesting the first comment....QuoteI like to solder all my lugs on for an even better connection. And in the example at the end where you cut through the 4 - 0 lug, you chose a location where it had not been crimped thereby showing an uncrimped gap inside. Not a nice demonstration. Solder has always been superior to crimp, throughout the history of cable lug use. Not sure where you went to school but we actually tested crimped vs soldered connections for resistance and noticed failures in current draw tests. The solder, when done correctly always produced better results than crimps when done correctly. In most applications, either will suffice. However, for pure results solder wins. Silver based solder is 5% more conductive than copper (copper 100%, silver 105% using copper as the standard conductor). Heating wire tends to distort the insulator so care must be used. I like to use a wet rag to cover the insulation near the end or an cooling paste which is available from most HVAC wholesalers. Silver requires a bit more heat than propane, though so most opt for the crimp. We're talking about the purest method here...in real life and in most situations the crimp will suffice. Its important to know the composition of the lug being used as well. Some are made of aluminum while some are copper and other's copper with a tinned coating. Best to choose one with copper, either bare or tinned, since aluminum tends to oxidize over time which creates friction within the lug. I've seen 'em glowing red like a toaster element from bad connection. I got about 50 years experience in this subject.
Purely from a resistive point of view that may be true, but overall I don’t think it is - solder will wick into the wire, and turn at least some of it, right where it emerges from the terminal, effectively into a solid conductor - right where it’s anchored and going to be subjected to the most stress. What breaks first when subjected to vibration - solid wire, or stranded wire?
Properly made crimps are mechanically sound, more resistant to vibration than soldered ones, and gas tight.
https://workmanship.nasa.gov/lib/insp/2%20books/links/sections/201%20General%20Requirements.html#:~:text=Crimping%20is%20an%20efficient%20and,design%20application%20and%20connectivity%20requirements.
I’ll stick with crimping, thankyouveryplease…
-Pat
Edit to add: copied from the first paragraph of the link above:
Crimped Terminations
Crimping is an efficient and highly reliable method to assemble and terminate conductors, and typically provides a stronger, more reliable termination method than that achieved by soldering.
No. Just no.
Solder joints are more difficult to do correctly, but when done so are almost always the better choice. The vibration point is a good one, but not really applicable for a home solar PV installation, unless you live directly above a seriously active tectonic fault zone.
What kind of soldering (station?) are you using for thick cables? Our everyday 80 W soldering station wont cut it, right?You need napalm...
...You should try to avoid having your second crimp overlap the first; this ensures that the wedge/plug you're talking about forms BETWEEN the two crimps, and the second crimp really is only "for good measure".
mnem
Oh, and right on aboot the fly... that made for some good cinema there.
You shouldn't crush the wedge at all. Copper has a very low elastic limit, and if you do that you lose the benefit of having a wedge.
...You should try to avoid having your second crimp overlap the first; this ensures that the wedge/plug you're talking about forms BETWEEN the two crimps, and the second crimp really is only "for good measure".
mnem
Oh, and right on aboot the fly... that made for some good cinema there.
You shouldn't crush the wedge at all. Copper has a very low elastic limit, and if you do that you lose the benefit of having a wedge.
The wedge does form if you do the 2nd crimp far enough away; it forms between the 2 crimps. A mm wide and deep (less, really) is all the wedge needs be to provide more than adequate mechanical strength. When I talk of the 2nd crimp being "for good measure" it is to increase the contact area under compression for lowest resistance, not mechanical strength.
These are not brake cables or the like; mechanical strength does not need to be that much in engineering terms to be stronger than any mechanical stress it should ever experience.
mnem
What kind of soldering (station?) are you using for thick cables?
Our everyday 80 W soldering station wont cut it, right?
I thought you won one of the 180 series SA mainframes, in the last PP auction, it should work in the SA mainframe, just some of the later ones haven't got the scope cal outputs, as they were made long after the scope modules became obsolete.
I'm I the only one on here with some 180 scopes in my collection?
David
I have a 181 here.
Lab Cat looking none too pleased with the poor probe compensation:
-Pat
A quick warning note for anyone with a HP 181T, 181A oscilloscope mainframe or spectrum analyzer display section (or older 141T,141S,141A), beware there is no protection for the storage CRT with excessive intensity, particularly in normal mode, where you can't see the trace bloom with high intensity setting, the storage mesh is often damaged on these from previous owners not RTFM, or clueless sellers that just turn every control to max until a trace appears.
Warning from 141T manual, need to add the 181 warning (aka, use Write & avoid Norm for setting intensity).
Another warning, when buying unknown condition 180/181 series mainframes, check the PSU is working correctly, before trying with known good plug-ins, as there was a mention of damage to the plug-ins from a faulty PSU.
Some of mine.....
David
I noted the same warning in the Tektronix RM564 manual ... which I still have not got round to powering it up. Eventually.... some day
I just want to note for the record that that photo was taken in rather dim lighting, so the phone camera horribly overexposed the appearance of the trace on the scope - it wasn’t set to eye-searing, screen-melting intensity despite the fact that it may seem to be. Also note how bright the pilot light looks, and how dimly lit everything else is in comparison. No CRTs were harmed in the production of that photograph.
-Pat
I guessed that you were trying to get the best possible picture of your fuzzy whiskered friend.
The wedge does form if you do the 2nd crimp far enough away; it forms between the 2 crimps. A mm wide and deep (less, really) is all the wedge needs be to provide more than adequate mechanical strength. When I talk of the 2nd crimp being "for good measure" it is to increase the contact area under compression for lowest resistance, not mechanical strength.
These are not brake cables or the like; mechanical strength does not need to be that much in engineering terms to be stronger than any mechanical stress it should ever experience. mnem
You haven't seen how some "engineers" rag on cables connecting big batteries in big strings... you'd think the prospect of instant death if there's a serious short would moderate their behaviour, but as the old saying goes "familiarity breeds contempt".
If you do the arithmetic, you'll see that even a single crimp will have more surface contact area than the cable CSA. I'm not saying it's inherently bad, I'm just saying I prefer the guaranteed mechanical strength over the possible few nano-ohms difference a second crimp makes.
Mostly these things will only make a difference in edge cases; I routinely "crimp" 10-95mm2 lugs with my trusty 2PH and a hammer (only if I don't have a proper crimper to hand and it needs to be done NOW. Bigger than 95mm2 and I need a hydraulic crimper which I don't have, so those have to wait until it gets hired). Haven't burned any buildings down yet.
Anothergrey box* red box (for a change) arrived today.
*I often get the comment "not another grey box" when large parcel(s) arrive.
David
Forgive the dumb question, but why not just put that tool in a vice to squeeze it smoothly instead of hammering it ?!
The smooth progressive action of the vice would be kind to the lug wouldn't it.
I mean a real big/full size garage vice of course, not the tiny vice we use in the lab, that goes without saying !