On Fri, 24 Dec 2021 20:36:33 -0000 (UTC), Cydrome Leader <presence@MUNGEpanix.com> wrote:>Tabby <tabbypurr@gmail.com> wrote: >> On Thursday, 23 December 2021 at 18:23:19 UTC, Rich S wrote: >>> On Tuesday, December 21, 2021 at 5:24:50 PM UTC, John Walliker wrote: >>> > On Tuesday, 21 December 2021 at 15:16:25 UTC, legg wrote: >>> > > On Tue, 21 Dec 2021 02:50:33 -0800 (PST), John Walliker >>> > > <jrwal...@gmail.com> wrote: >>> > > >>> > > >On Tuesday, 21 December 2021 at 04:05:42 UTC, Sylvia Else wrote: >>> > > >> On 21-Dec-21 2:16 pm, Cydrome Leader wrote: >>> > > >> > What do you folks think about this gem: >>> > > >> > >>> > > >> > https://www.youtube.com/watch?v=cpaWCedoptA >>> > > >> > >>> > > >> > I like the special high reluctance transformer and kindling used as >>> > > >> > insulation. >>> > > >> > >>> > > >> > >>> > > >> No Earth. >>> > > >> >>> > > >> Joining wires by twisting alone is asking for a fire. >>> > > >> >>> > > >> Sylvia. >>> > > > >>> > > >They did solder the connection to the rectifier diode. I thought it >>> > > >was quite impressive. A lot of thought had gone into the design >>> > > >and it certainly made good use of recycled materials. >>> > > > >>> > > >John >>> > > Besides the craft paper substitution, what made you think that >>> > > the materials were recycled? Repurposed, maybe. >>> > > >>> > > RL >>> > That is what I was mainly thinking of. The core looked as if it might >>> > have been intended for some other purpose. I suppose the rust and >>> > grime on the laminations are good for reducing eddy currents. It did >>> > seem surprising that the guillotine operator appeared to have all his >>> > fingers. The diode heatsink casting might well have been recycled >>> > aluminium floor sweepings >>> > >>> > John >>> I'm most struck by their work practices. Working on cracked concrete >>> floor, no tables or chairs. I realize some cultural ethic may be a >>> factor, but ergonomics & safety are "universal". Also, strange that >>> they have some hand tools, like pliers, but no wire cutters (scissors >>> is a painful way to cut wire!) or rubber mallet. And they have some >>> power tools like the drill press and circular saw, but no electric or >>> pneumatic screw/nut drivers, riveters, etc. And a sheet metal shear. >>> I wonder if electricity there is a premium? Karachi is the capital city, >>> but I would think, make electricity as available as possible for >>> business-sector development. They might do well to host a >>> manufacturing engineering consultant for a few days. >> >> I'm sure they could teach a consultant more than the consultant could teach them. I would want to use a pushsstick though on that guillotine. >> >> The wire isn't copper colour. I can't imagine them paying unnecessarily for plating. It's not iron wire is it? :) > >It looked like cloth covered wire for the transformer. I can't imagine >that's cheaper than varnish, but maybe there's another shop where they >twist it on by hand.Cloth-covered wire is very robust when the whole assembly is varnished, and can withstand a fair voltage. Probably cheaper than regular enameled magnet wire, as that is actually quite difficult to manufacture. Joe Gwinn
review this battery charger
Started by ●December 20, 2021
Reply by ●December 24, 20212021-12-24
Reply by ●December 24, 20212021-12-24
On Fri, 24 Dec 2021 20:36:33 -0000 (UTC), Cydrome Leader <presence@MUNGEpanix.com> wrote:>It looked like cloth covered wire for the transformer. I can't imagine >that's cheaper than varnish, but maybe there's another shop where they >twist it on by hand.In India: Cotton cloth costs Rs 65 ($0.85) per meter. <https://dir.indiamart.com/impcat/plain-cotton-fabric.html> Varnish costs about Rs 145 ($1.92) per kg. <https://dir.indiamart.com/search.mp?ss=varnish> I don't know the relative wire coverage area for cloth vs varnish, but they seem about equal. However, applying cloth insulation is a one step process, while varnish requires thinning, dipping, drying, careful winding, testing for shorts, etc. Cloth seems easier. -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558
Reply by ●December 27, 20212021-12-27
On 21/12/2021 1:16 pm, Cydrome Leader wrote:> What do you folks think about this gem: > > https://www.youtube.com/watch?v=cpaWCedoptA > > I like the special high reluctance transformer and kindling used as > insulation. > >It is the result of poverty.
Reply by ●December 27, 20212021-12-27
On Tue, 21 Dec 2021 03:16:43 -0000 (UTC), Cydrome Leader <presence@MUNGEpanix.com> wrote:>What do you folks think about this gem: > >https://www.youtube.com/watch?v=cpaWCedoptA > >I like the special high reluctance transformer and kindling used as >insulation. >Looks inefficient. Fiberglass wire so it can run hot? Half-wave rectifier. These are people who find it worthwhile to rebuild truck batteries: https://youtu.be/afwO_MZjRjA Hopefully they can achieve a minimal level of prosperity at some point in the not-too-distant future. OBOR should help a lot. -- Best regards, Spehro Pefhany
Reply by ●December 27, 20212021-12-27
On Monday, December 20, 2021 at 10:16:48 PM UTC-5, Cydrome Leader wrote:> What do you folks think about this gem: > > https://www.youtube.com/watch?v=cpaWCedoptA > > I like the special high reluctance transformer and kindling used as > insulation.Typical of the third world shit countries that have no respect for their people. So those tools will work the better part of a day to to produce some garbage that's not even close to 15 minutes of western productivity. Those cesspools have resources, they don't have to work like that.
Reply by ●December 29, 20212021-12-29
On Saturday, 25 December 2021 at 02:59:09 UTC, jeff.li...@gmail.com wrote:> On Fri, 24 Dec 2021 20:36:33 -0000 (UTC), Cydrome Leader > <pres...@MUNGEpanix.com> wrote: > > >It looked like cloth covered wire for the transformer. I can't imagine > >that's cheaper than varnish, but maybe there's another shop where they > >twist it on by hand. > In India: > Cotton cloth costs Rs 65 ($0.85) per meter. > <https://dir.indiamart.com/impcat/plain-cotton-fabric.html>1m means something like 1x2m, though the width varies> Varnish costs about Rs 145 ($1.92) per kg. > <https://dir.indiamart.com/search.mp?ss=varnish> > > I don't know the relative wire coverage area for cloth vs varnish, but > they seem about equal.If we guess wildly at 10mm circumference for the cloth insulation: 1x2m = 2sqm 10mm x 1m = So number of meters it covers = 2m/10mm = 200m> However, applying cloth insulation is a one > step process,yes, one painfully slow process> while varnish requires thinning, dipping, drying,I assumed it would set/dry almost instantly, probably applied hot. I can't see much upside in using a formula that doesn't.> careful winding, testing for shorts, etc.I doubt they'd bother> Cloth seems easier.If I were in the 3rd world looking to go ultracheap I'd possibly pick hot bitumenised paper. Those transformers look big but either a) they're way ott for charging truck batteries b) or they're for something else, probably stealing power
Reply by ●December 30, 20212021-12-30
Tabby <tabbypurr@gmail.com> wrote:> On Saturday, 25 December 2021 at 02:59:09 UTC, jeff.li...@gmail.com wrote: >> On Fri, 24 Dec 2021 20:36:33 -0000 (UTC), Cydrome Leader >> <pres...@MUNGEpanix.com> wrote: >> >> >It looked like cloth covered wire for the transformer. I can't imagine >> >that's cheaper than varnish, but maybe there's another shop where they >> >twist it on by hand. >> In India: >> Cotton cloth costs Rs 65 ($0.85) per meter. >> <https://dir.indiamart.com/impcat/plain-cotton-fabric.html> > > 1m means something like 1x2m, though the width varies > >> Varnish costs about Rs 145 ($1.92) per kg. >> <https://dir.indiamart.com/search.mp?ss=varnish> >> >> I don't know the relative wire coverage area for cloth vs varnish, but >> they seem about equal. > > If we guess wildly at 10mm circumference for the cloth insulation: > 1x2m = 2sqm > 10mm x 1m = > So number of meters it covers = 2m/10mm = 200m > >> However, applying cloth insulation is a one >> step process, > > yes, one painfully slow processIn the real world (so not the slums of pakistan) cloth insulation is woven on with a machine and not cut up from bedsheets or whatever else you folks are looking at.>> while varnish requires thinning, dipping, drying, > > I assumed it would set/dry almost instantly, probably applied hot. I can't see much upside in using a formula that doesn't. > >> careful winding, testing for shorts, etc. > > I doubt they'd bother > >> Cloth seems easier. > > If I were in the 3rd world looking to go ultracheap I'd possibly pick > hot bitumenised paper. > > Those transformers look big but either > a) they're way ott for charging truck batteries > b) or they're for something else, probably stealing powerthey look about right to charge a truck battery, considering they're probably about 50% efficient.
Reply by ●December 30, 20212021-12-30
On 2021-12-30, Cydrome Leader <presence@MUNGEpanix.com> wrote:> Tabby <tabbypurr@gmail.com> wrote: >> On Saturday, 25 December 2021 at 02:59:09 UTC, jeff.li...@gmail.com wrote: >>> On Fri, 24 Dec 2021 20:36:33 -0000 (UTC), Cydrome Leader >>> <pres...@MUNGEpanix.com> wrote: >>> >>> >It looked like cloth covered wire for the transformer. I can't imagine >>> >that's cheaper than varnish, but maybe there's another shop where they >>> >twist it on by hand. >>> In India: >>> Cotton cloth costs Rs 65 ($0.85) per meter. >>> <https://dir.indiamart.com/impcat/plain-cotton-fabric.html> >> >> 1m means something like 1x2m, though the width varies >> >>> Varnish costs about Rs 145 ($1.92) per kg. >>> <https://dir.indiamart.com/search.mp?ss=varnish> >>> >>> I don't know the relative wire coverage area for cloth vs varnish, but >>> they seem about equal. >> >> If we guess wildly at 10mm circumference for the cloth insulation: >> 1x2m = 2sqm >> 10mm x 1m = >> So number of meters it covers = 2m/10mm = 200m >> >>> However, applying cloth insulation is a one >>> step process, >> >> yes, one painfully slow process > > In the real world (so not the slums of pakistan) cloth insulation is woven > on with a machine and not cut up from bedsheets or whatever else you folks > are looking at. > >>> while varnish requires thinning, dipping, drying, >> >> I assumed it would set/dry almost instantly, probably applied hot. I can't see much upside in using a formula that doesn't. >> >>> careful winding, testing for shorts, etc. >> >> I doubt they'd bother >> >>> Cloth seems easier. >> >> If I were in the 3rd world looking to go ultracheap I'd possibly pick >> hot bitumenised paper. >> >> Those transformers look big but either >> a) they're way ott for charging truck batteries >> b) or they're for something else, probably stealing power > > they look about right to charge a truck battery, considering they're > probably about 50% efficient.yeah, the core is made from scrap, not from a transformer alloy so it will need to run lower flux levels to avoid saturation. I'm sure they are better than 50% energy efficient, but they are'nt space or mass efficient. If their customers are all nearby the extra shipping costs are not a big problem. -- Jasen.
Reply by ●December 30, 20212021-12-30
On 2021-12-30, Cydrome Leader <presence@MUNGEpanix.com> wrote:> Tabby <tabbypurr@gmail.com> wrote: >> On Saturday, 25 December 2021 at 02:59:09 UTC, jeff.li...@gmail.com wrote: >>> On Fri, 24 Dec 2021 20:36:33 -0000 (UTC), Cydrome Leader >>> <pres...@MUNGEpanix.com> wrote: >>> > > In the real world (so not the slums of pakistan) cloth insulation is woven > on with a machine and not cut up from bedsheets or whatever else you folks > are looking at. >thw wire was coming off a spool and appaeared to have machine woven cotton insulation,>> Those transformers look big but either >> a) they're way ott for charging truck batteries >> b) or they're for something else, probably stealing power > > they look about right to charge a truck battery, considering they're > probably about 50% efficient.yeah, the core is made from scrap, not from a transformer alloy so it will need to run lower flux levels to avoid saturation. I'm sure they are better than 50% energy efficient, a microwave oven transformer is better than 70% efficient but still needs forced air cooling - these are larger and have no mechanical cooling. However they aren't space or mass efficient. If their customers are all nearby the extra shipping costs caused by this bulkiness are not a big problem. -- Jasen.
Reply by ●December 30, 20212021-12-30
On Thursday, 30 December 2021 at 18:48:06 UTC, Cydrome Leader wrote:> Tabby <tabb...@gmail.com> wrote: > > On Saturday, 25 December 2021 at 02:59:09 UTC, jeff.li...@gmail.com wrote: > >> On Fri, 24 Dec 2021 20:36:33 -0000 (UTC), Cydrome Leader > >> <pres...@MUNGEpanix.com> wrote: > >> > >> >It looked like cloth covered wire for the transformer. I can't imagine > >> >that's cheaper than varnish, but maybe there's another shop where they > >> >twist it on by hand. > >> In India: > >> Cotton cloth costs Rs 65 ($0.85) per meter. > >> <https://dir.indiamart.com/impcat/plain-cotton-fabric.html> > > > > 1m means something like 1x2m, though the width varies > > > >> Varnish costs about Rs 145 ($1.92) per kg. > >> <https://dir.indiamart.com/search.mp?ss=varnish> > >> > >> I don't know the relative wire coverage area for cloth vs varnish, but > >> they seem about equal. > > > > If we guess wildly at 10mm circumference for the cloth insulation: > > 1x2m = 2sqm > > 10mm x 1m = > > So number of meters it covers = 2m/10mm = 200m > > > >> However, applying cloth insulation is a one > >> step process, > > > > yes, one painfully slow process > In the real world (so not the slums of pakistan) cloth insulation is woven > on with a machine and not cut up from bedsheets or whatever else you folks > are looking at.heh. I assume folk were looking at cloth to estimate the cost of woven tube.> >> while varnish requires thinning, dipping, drying, > > > > I assumed it would set/dry almost instantly, probably applied hot. I can't see much upside in using a formula that doesn't. > > > >> careful winding, testing for shorts, etc. > > > > I doubt they'd bother > > > >> Cloth seems easier. > > > > If I were in the 3rd world looking to go ultracheap I'd possibly pick > > hot bitumenised paper. > > > > Those transformers look big but either > > a) they're way ott for charging truck batteries > > b) or they're for something else, probably stealing power > they look about right to charge a truck battery, considering they're > probably about 50% efficient.They should be nearer to 100% than 50. A truck battery is what, 200Ah or so, or for an old Indian truck maybe 30Ah. Looking to cut costs always I doubt they'd charge it at more than 6A. They only need a short charge to get it started or a slow charge after rebuilding a battery. That's a huge transformer for 6A.
