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nuckolls.bob(at)aeroelect
Guest

Posted: Thu Apr 06, 2017 8:32 am Post subject: Today's trivia dump . . .

I think I've written about a project to repeat the

 experiment I did on AA alkaline cells 14 years ago . . .



  http://tinyurl.com/mhztc2b



 I've been keeping a constellation of AA-cell products

 in the super-duper-battery-runner-downer for several

 weeks and at first blush at most of the data, the

 original deductions about alkaline cell quality vs.

 costs and advertising hype haven't changed. 



 There are a couple interesting things I've discovered

 that I'll share with the List.



 There's a line of alkaline cells purported to be

 enhanced with lithium. A noteworthy example is

 the Energizer 'Advanced Lithium' brand. These

 are not lithium-ion cells . . . they still present

 the expected 1.6 volt/cell open circuit potential

 as their rudimentary cousins but unlike MOST 'enhanced

 formulas' these do indeed offer improved performance in the

 same envelope.



 The energy traces below show a generic pair of alkaline

 AA cells that have delivered ~1.4 Watt-Hrs of energy . . .

 about the same numbers as the first experiment in 2002.



 Then we have a trio of traces that have delivered 3.6

 Watt-Hrs of energy or about 2.5 times that of the

 non-lithium cell. 



 There are three additional traces of interest . . . they

 too are generated by the discharge test of some advanced

 lithium cells. The general shape of the curves are the

 same as for the first three described above . . . but they

 averaged a  15% lower value of delivered energy and the output

 voltage is 'ragged' or unstable.



 

 [img]cid:.0[/img]



 This is caused by tiny amounts of resistance introduced

 by the connections to the test equipment that can arise when

 the cells are connected with the spring-loaded holders

 common to 99.999% of all cylindrical cell powered products.



 [img]cid:.1[/img]



 These resistance values are small . . . and generally have

 little effect on appliance performance for applications

 with smaller current demands. The tests I'm conducting use

 a 300 mA constant current discharge rate. At this rate . . .

 and anything higher . . . there is a potential for battery

 holder resistance to degrade system performance.



 This fact is part of the foundation for why I explored

 and ultimately recommended the 9v alkaline cells in a standby

 battery application a few days ago. The very low current

 demand in the application under discussion did not exclude

 the 9V cell.



 Obviously, the AA cell offers a larger energy bucket for

 such tasks . . . but getting a firm electrical grip on

 the cell's electrical energy is a bit more problematic.



 My energy studies are being conducted with cells having

 SOLDERED leads eliminating the holder issues . . .

 indeed, one could build up disposable cell arrays using

 similar techniques. But they need to be done with care

 lest the cells be damaged by soldering heat.



 It would be really cool to use tab-welders common the Ni-Mh

 and Li-Ion arrays. The AA alkaline cell has a really small

 (+) terminal . . . more difficult to weld on. I have some

 alkaline D-cell arrays for video cameras that were welded . . .

 but the AA-cell is more problematic.



 I may do an article on the techniques I use for soldering

 to AA-cell . . . it's not difficult.



 It seems that the past few weeks discoveries in my AA-cell

 testing offer another choice for DIY standby battery 

 construction. As soon as I've squashed all the energy

 out of the current constellation of test articles, I'll

 do some testing on the effects of soldered leads.



 Watch this space . . . 



 

   Bob . . .

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yellowduckduo(at)gmail.co
Guest

Posted: Thu Apr 06, 2017 10:13 am Post subject: Today's trivia dump . . .

Good to see some quantified info on the advanced li alkalines.



While I've soldered a number of tabs on alkaline batteries it seems that 

DIY tab welders are somewhat common for building battery packs. In the 

crudest form, just two handheld copper wire "electrodes" fed by a lead 

acid battery.  More advanced units are AC powered using a few volts from 

a couple of secondary turns on an old transformer and timed current 

pulses. Two pulses of 50 ms or so each from what I've learned so far.

Ken

jim(at)PoogieBearRanch.co
Guest

Posted: Thu Apr 06, 2017 10:13 am Post subject: Today's trivia dump . . .

Bob,

Thanks for this update. I had been really wondering if those Energizer "Advanced Lithium" batteries were worth the extra cost. I just did a lookup on Amazon to find the current pricing for the AA cells â€“ seems to be around $1.27 each (cheapest I could find). By comparison, the Kirkland brand alkaline cells from CostCo run about $0.25 per cell. Even if the "Lithium" cells last 3 times longer, they still cost 5 times as much! Looks like your old advice from 2002 still rings true: "Buy cheap and change often!"

By the way, I recently went on a lengthy cross-country trip in my '65 Champion 7ECA (pre-dates the "Citabria" name...) only to have the PTT wiring under the stick the short out. That gave me a "hot mike" until I shut off the aircraft radio. I switched over to my SP-400, which had an alkaline battery pack installed that had already been used for 4+ hours last year at OSH (listening to the Sunday arrivals). That pack lasted another 4+ hours of "normal" use in the cockpit before the SP-400 would no longer transmit. I keep a spare battery pack loaded and ready to go (the only reason I didn't put new batteries in the 1st pack), so I switched to the new pack to complete the flight. The "new" batteries show a "full" charge on the SP-400 battery meter after about an hour of use in flight.

By the way, with the SP-400 connected to a dedicated coax and external VHF comm antenna and a headset adapter, I was able to talk to both enroute ATC and our local tower from 15 miles away pretty clearly, with only a bit of "scratchiness" at 20 miles (still understandable to them, though). Reception-only range was well over 30 miles. 

Jim Parker



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Eric Page

Joined: 15 Feb 2017
Posts: 245

Posted: Thu Apr 06, 2017 1:15 pm Post subject: Today's trivia dump . . .

For anyone interested in this project, search YouTube for "MOT spot welder" and you'll find a number of videos on the subject of using a microwave oven transformer (MOT) to build a spot welder.



Eric

 	  Quote: 	
		   On Apr 6, 2017, at 11:10 AM, C&K <yellowduckduo(at)gmail.com> wrote:

 While I've soldered a number of tabs on alkaline batteries it seems that DIY tab welders are somewhat common for building battery packs. In the crudest form, just two handheld copper wire "electrodes" fed by a lead acid battery.  More advanced units are AC powered using a few volts from a couple of secondary turns on an old transformer and timed current pulses. Two pulses of 50 ms or so each from what I've learned so far.

stuart(at)stuarthutchison
Guest

Posted: Thu Apr 06, 2017 1:35 pm Post subject: Today's trivia dump . . .

At around 3200mAh, the energy density of typical Lithium primary (non-rechargeable) cells - which are not the same as Li-Ion secondary (rechargeable) technology - is only about 15% more than a typical quality Alkaline cell (about 2800mAh).  The reason for the claims of 5-7 times longer lasting in high-energy devices is the C-rate. In other words, Lithium cells can deliver their stored potential at a higher rate of current without increasing internal resistance and getting hot.  Energy can neither be created nor destroyed, so when Alkaline cells used in high-energy devices get hot, the heat represents a â€˜lossâ€™ or waste of stored energy from the cell itself.  So, it is not that Lithium cells have 5-7 times more stored energy density (commensurate with the price difference), but Lithium cells can deliver much more of their energy without the wasting it as heat.  Putting Lithium batteries in a very low drain wall-mounted clock would be pointless, but in my Infra-Red Night Vision hunting scope they are excellent value for money.

V/R Stu



[quote]On 7 Apr 2017, at 04:10, <jim(at)poogiebearranch.com (jim(at)poogiebearranch.com)> <jim(at)poogiebearranch.com (jim(at)poogiebearranch.com)> wrote:

   Bob,



Thanks for this update. I had been really wondering if those Energizer "Advanced Lithium" batteries were worth the extra cost. I just did a lookup on Amazon to find the current pricing for the AA cells â€“ seems to be around $1.27 each (cheapest I could find). By comparison, the Kirkland brand alkaline cells from CostCo run about $0.25 per cell. Even if the "Lithium" cells last 3 times longer, they still cost 5 times as much! Looks like your old advice from 2002 still rings true: "Buy cheap and change often!"



By the way, I recently went on a lengthy cross-country trip in my '65 Champion 7ECA (pre-dates the "Citabria" name...) only to have the PTT wiring under the stick the short out. That gave me a "hot mike" until I shut off the aircraft radio. I switched over to my SP-400, which had an alkaline battery pack installed that had already been used for 4+ hours last year at OSH (listening to the Sunday arrivals). That pack lasted another 4+ hours of "normal" use in the cockpit before the SP-400 would no longer transmit. I keep a spare battery pack loaded and ready to go (the only reason I didn't put new batteries in the 1st pack), so I switched to the new pack to complete the flight. The "new" batteries show a "full" charge on the SP-400 battery meter after about an hour of use in flight.



By the way, with the SP-400 connected to a dedicated coax and external VHF comm antenna and a headset adapter, I was able to talk to both enroute ATC and our local tower from 15 miles away pretty clearly, with only a bit of "scratchiness" at 20 miles (still understandable to them, though). Reception-only range was well over 30 miles. 



Jim Parker



 [quote]  ------

nuckolls.bob(at)aeroelect
Guest

Posted: Thu Apr 06, 2017 2:00 pm Post subject: Today's trivia dump . . .

At 04:31 PM 4/6/2017, you wrote:

  	  Quote: 	
		  At around 3200mAh, the energy density of typical Lithium primary (non-rechargeable) cells - which are not the same as Li-Ion secondary (rechargeable) technology - is only about 15% more than a typical quality Alkaline cell (about 2800mAh).  The reason for the claims of 5-7 times longer lasting in high-energy devices is the C-rate. In other words, Lithium cells can deliver their stored potential at a higher rate of current without increasing internal resistance and getting hot.  Energy can neither be created nor destroyed, so when Alkaline cells used in high-energy devices get hot, the heat represents a â€˜lossâ€™ or waste of stored energy from the cell itself.  So, it is not that Lithium cells have 5-7 times more stored energy density (commensurate with the price difference), but Lithium cells can deliver much more of their energy without the wasting it as heat.  Putting Lithium batteries in a very low drain wall-mounted clock would be pointless, but in my Infra-Red Night Vision hunting scope they are excellent value for money.



 V/R Stu

 	


   I have encountered AA cells offered with creative

   advertising hyperbole . . . and found them to

   be short on snort.



   However, the cells I posted about earlier today

   were discharged on an well instrumented, 300 mA

   constant current load. So irrespective of the

   cell's c-rate, I was comparing the various

   offerings under identical test conditions.



   I'll do some more detailed comparisons of these

   cells and get some internal resistance measurements

   at various points along their discharge profiles.



 

   Bob . . .

nuckolls.bob(at)aeroelect
Guest

Posted: Thu Apr 06, 2017 2:05 pm Post subject: Today's trivia dump . . .

At 04:11 PM 4/6/2017, you wrote:

  	  Quote: 	
		  --> AeroElectric-List message posted by: Eric Page <edpav8r(at)yahoo.com>



 For anyone interested in this project, search YouTube for "MOT spot welder" and you'll find a number of videos on the subject of using a microwave oven transformer (MOT) to build a spot welder. 	


   I've seen those . . . while economical in

   terms of purchased materials, they're kinda

   labor intensive. I'm toying with the notion

   of trying one of these.



  http://tinyurl.com/knl5wrf



 

 

   Bob . . .

Eric Page

Joined: 15 Feb 2017
Posts: 245

Posted: Thu Apr 06, 2017 10:09 pm Post subject: Re: Today's trivia dump . . .

Indeed; plus the dangers inherent in a mains-powered project.



I hadn't yet seen the eBay item you linked.  The Chinese manufacturers never cease to amaze with their ability to crank out high-dollar items at bargain basement prices.



This got me thinking about a simple way to accomplish this with stuff we might have on hand at the bench or could get cheap-and-quick.  With the idea that lead-acid batteries are ubiquitous, safe and able to provide ample current to weld the tiny spots needed to secure battery tabs, here's what I came up with:



http://preview.tinyurl.com/knz5te2



...using a solenoid like this:



http://preview.tinyurl.com/n88f7tl



This could probably be lashed together in half an hour, for a few dollars in parts.  Thoughts?



Eric

 	  Robert L. Nuckolls, III wrote: 	
		  

I've seen those . . . while economical in terms of purchased materials, they're kinda labor intensive. I'm toying with the notion of trying one of these.



http://tinyurl.com/knl5wrf



Bob . . .

nuckolls.bob(at)aeroelect
Guest

Posted: Fri Apr 07, 2017 5:32 am Post subject: Today's trivia dump . . .

At 01:09 AM 4/7/2017, you wrote:

  	  Quote: 	
		  --> AeroElectric-List message posted by: "Eric Page" <edpav8r(at)yahoo.com>



 Indeed; plus the dangers inherent in a mains-powered project.



 I hadn't yet seen the eBay item you linked.  The Chinese manufacturers never cease to amaze with their ability to crank out high-dollar items at bargain basement prices.



 This got me thinking about a simple way to accomplish this with stuff we might have on hand at the bench or could get cheap-and-quick.  With the idea that lead-acid batteries are ubiquitous, safe and able to provide ample current to weld the tiny spots needed to secure battery tabs, here's what I came up with:



  http://preview.tinyurl.com/knz5te2

 	


   This is almost exactly what I crafted to

   replace the failed pulse controller on a friend's

   spot welder some years ago. This was an AC welder

   so I could use a photo coupled triac to control

   primary supply current. The only questions that come

   to mind immediately about the battery+contactor

   configuration is the ability to control pulse current

   as well . . . some high current resistors (i've used

   coils of steel clothesline wire). Also, you may want

   to craft your solenoid driver to withstand the inductive

   kick inherent in the solenoid's windings. Adding

   a diode causes a large contactor increase in drop-out-delay

   which MIGHT affect your selection of optimum current

   x time . . . or not.



   But the thing is worth pursuing . . . we could do

   an Eric's Shop Notes page on the website to assist

   others in repeating a useful experiment.



 

 

   Bob . . .

nuckolls.bob(at)aeroelect
Guest

Posted: Fri Apr 07, 2017 7:26 am Post subject: Today's trivia dump . . .

At 01:10 PM 4/6/2017, you wrote:

  	  Quote: 	
		  Bob,



 Thanks for this update. I had been really wondering if those Energizer "Advanced Lithium" batteries were worth the extra cost. I just did a lookup on Amazon to find the current pricing for the AA cells – seems to be around $1.27 each (cheapest I ccould find). By comparison, the Kirkland brand alkaline cells from CostCo run about $0.25 per cell. Even if the "Lithium" cells last 3 times longer, they still cost 5 times as much! Looks like your old advice from 2002 still rings true: "Buy cheap and change often!" 	


   Agreed . . . but with this 'special case'.

   As a primary cell standby battery, cost of

   ownership has to include a significant 

   $time$ expense. It occurs to me that a

   welded (or carefully soldered) array of

   these more robust cells might well offer

   an attractive option for keeping these

   nifty little panel appliances running

   in situations where our preventative

   maintenance and/or less than artfully

   conducted FMEA does trigger a black-panel-

   syndrome.



   'Standby' batteries have been an intuitively

   seductive idea since the first panel mounted

   electro-whizzy was installed on an airplane.



   As we've discussed on the List many times

   over the years, bad days in the cockpit are

   rarely based on loss of electrical power . . .

   and when they do include total electrical

   failure, we have generally deduced root cause

   to be something OTHER than deficient hardware.

   System architecture and/or pilot ignorance

   plays a major role in virtually every

   dark-n-stormy night story published in the

   popular aviation rags.



   The alkaline AA cell is a demonstrably

   robust and predictable source of energy.

   In the very first edition of the 'Connection,

   I suggested DIY arrays of alkaline D-cells

   as a potential back-up source. In the 25+ years

   since, energy requirements for some useful appliances

   are so low that the lowly 9v transistor radio

   battery becomes a EMF to consider . . . with

   attractive cost, weight, volume and performance

   ratios.



   This exploration into a world of flight

   forced into Plan-C operations SHOULD be more

   academic than practical . . . but it sounds

   like fun.



 

   Bob . . .

ashleysc(at)broadstripe.n
Guest

Posted: Fri Apr 07, 2017 8:14 am Post subject: Today's trivia dump . . .

Hi Bob;



Hi All;

This is good work that you do. Much preferable to trusting manufacturer's hype.

Cheers!   Stu.

From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>

To: aeroelectric-list(at)matronics.com

Sent: Thursday, April 6, 2017 9:29:08 AM

Subject: Today's trivia dump . . .

  I think I've written about a project to repeat the

 experiment I did on AA alkaline cells 14 years ago . . .

  http://tinyurl.com/mhztc2b

 I've been keeping a constellation of AA-cell products

 in the super-duper-battery-runner-downer for several

 weeks and at first blush at most of the data, the

 original deductions about alkaline cell quality vs.

 costs and advertising hype haven't changed. 

 There are a couple interesting things I've discovered

 that I'll share with the List.

 There's a line of alkaline cells purported to be

 enhanced with lithium. A noteworthy example is

 the Energizer 'Advanced Lithium' brand. These

 are not lithium-ion cells . . . they still present

 the expected 1.6 volt/cell open circuit potential

 as their rudimentary cousins but unlike MOST 'enhanced

 formulas' these do indeed offer improved performance in the

 same envelope.

 The energy traces below show a generic pair of alkaline

 AA cells that have delivered ~1.4 Watt-Hrs of energy . . .

 about the same numbers as the first experiment in 2002.

 Then we have a trio of traces that have delivered 3.6

 Watt-Hrs of energy or about 2.5 times that of the

 non-lithium cell. 

 There are three additional traces of interest . . . they

 too are generated by the discharge test of some advanced

 lithium cells. The general shape of the curves are the

 same as for the first three described above . . . but they

 averaged a  15% lower value of delivered energy and the output

 voltage is 'ragged' or unstable.

 

 [img]cid:.0[/img]

 This is caused by tiny amounts of resistance introduced

 by the connections to the test equipment that can arise when

 the cells are connected with the spring-loaded holders

 common to 99.999% of all cylindrical cell powered products.

 [img]cid:.1[/img]

 These resistance values are small . . . and generally have

 little effect on appliance performance for applications

 with smaller current demands. The tests I'm conducting use

 a 300 mA constant current discharge rate. At this rate . . .

 and anything higher . . . there is a potential for battery

 holder resistance to degrade system performance.

 This fact is part of the foundation for why I explored

 and ultimately recommended the 9v alkaline cells in a standby

 battery application a few days ago. The very low current

 demand in the application under discussion did not exclude

 the 9V cell.

 Obviously, the AA cell offers a larger energy bucket for

 such tasks . . . but getting a firm electrical grip on

 the cell's electrical energy is a bit more problematic.

 My energy studies are being conducted with cells having

 SOLDERED leads eliminating the holder issues . . .

 indeed, one could build up disposable cell arrays using

 similar techniques. But they need to be done with care

 lest the cells be damaged by soldering heat.

 It would be really cool to use tab-welders common the Ni-Mh

 and Li-Ion arrays. The AA alkaline cell has a really small

 (+) terminal . . . more difficult to weld on. I have some

 alkaline D-cell arrays for video cameras that were welded . . .

 but the AA-cell is more problematic.

 I may do an article on the techniques I use for soldering

 to AA-cell . . . it's not difficult.

 It seems that the past few weeks discoveries in my AA-cell

 testing offer another choice for DIY standby battery 

 construction. As soon as I've squashed all the energy

 out of the current constellation of test articles, I'll

 do some testing on the effects of soldered leads.

 Watch this space . . . 

 

   Bob . . .

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Eric Page

Joined: 15 Feb 2017
Posts: 245

Posted: Fri Apr 07, 2017 1:07 pm Post subject: Re: Today's trivia dump . . .

Good catch; there's not much point in having 50mS pulses if the relay takes 1/3 of that again to release.  I've added a 200V Zener across the coil to allow its stored energy to dissipate faster.  I changed the MOSFET to an Infineon IPA65R650CEXKSA1 that's Vds=650V rated, and I've annotated a minimum Vds=500V for substitution.



Updated schematic:

http://preview.tinyurl.com/knz5te2



WRT pulse current, I suppose you could use a power resistor or DIY facsimile -or- get fancy with a beefy MOSFET gated by a pot-controlled op-amp sensing a shunt.  Based on the results shown in the various YouTube videos on this subject, my gut says current control isn't really necessary for the limited purpose of welding tabs onto cells.  I think my first go at this would be to just control heat with pulse width.  More R would be easy to add if found necessary.



Let me know if I can put this together and send it to you to try.  I don't have a need for it at the moment and my ability to measure how it works is limited (most of my equipment is in storage), but I do have the time to build it if you can get some use from it or if you think it will add to our collective tool box.



Is there anything else you would suggest changing?



Eric

 	  Robert L. Nuckolls, III wrote: 	
		  At 01:09 AM 4/7/2017, you wrote:

This is almost exactly what I crafted to replace the failed pulse controller on a friend's spot welder some years ago. This was an AC welder so I could use a photo coupled triac to control primary supply current. The only questions that come to mind immediately about the battery+contactor configuration is the ability to control pulse current as well . . . some high current resistors (i've used coils of steel clothesline wire). Also, you may want to craft your solenoid driver to withstand the inductive kick inherent in the solenoid's windings. Adding a diode causes a large contactor increase in drop-out-delay which MIGHT affect your selection of optimum current x time . . . or not.



But the thing is worth pursuing . . . we could do an Eric's Shop Notes page on the website to assist others in repeating a useful experiment.



Bob . . .

nuckolls.bob(at)aeroelect
Guest

Posted: Fri Apr 07, 2017 4:11 pm Post subject: Today's trivia dump . . .

 	  Quote: 	
		  WRT pulse current, I suppose you could use a power resistor or DIY facsimile -or- get fancy with a beefy MOSFET gated by a pot-controlled op-amp sensing a shunt.  Based on the results shown in the various YouTube videos on this subject, my gut says current control isn't really necessary for the limited purpose of welding tabs onto cells.  I think my first go at this would be to just control heat with pulse width.  More R would be easy to add if found necessary. 	
 

 



   Remember that total heat = K x T x I(SQUARED)



   . . . while there will be some current limiting

   offered by wiring and contactor resistance, the

   'weld current' available from a healthy battery

   can exceed many hundreds of amps.



   I would sure build in some sort of limiting.

   It occurs to me that incandescent lamps in

   parallel might offer an interesting current

   profile.



   Inrush tapering over tens of milliseconds

   will come asymptotic to the running current

   about 100 mS later. So an array of 10, 55w lamps

   (4A running) would settle out at 40a but deliver

   a pretty good start up jolt . . .



   Just a thought. In any case, an open coil of clothesline

   wire can be a pretty rugged, adjustable limiter. Used

   the stuff in a motor inrush controller for the a/c

   compressor motor on King Airs wayyyyy back when . . .



   Bob . . .

Eric Page

Joined: 15 Feb 2017
Posts: 245

Posted: Sun Apr 09, 2017 5:02 pm Post subject: Today's trivia dump . . .

 	  Quote: 	
		   On Apr 7, 2017, at 5:08 PM, Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com> wrote:

 I would sure build in some sort of limiting.


	


You mentioned 40A.  Would that be our target for max current in a system like this?  Would we want adjustability, and if so, through what range?



I have zero PIC time with a spot welder, hence the questions...



Eric

Eric Page

Joined: 15 Feb 2017
Posts: 245

Posted: Sun May 07, 2017 9:11 am Post subject: Re: Today's trivia dump . . .

Just to close the loop on this thread...



We exchanged a few posts a couple of weeks ago about the feasibility of making a DIY spot welder for attaching battery tabs.  I've been fiddling with the idea since then and have come to the conclusion that there's little point in trying to beat the Chinese at their own game.



With the components, an enclosure, some heavy gauge wire and something rigid and durable (tungsten TIG rod?) as welding tips, my bill of materials ended up nearly as costly as the imported spot welder that Bob found on eBay.  The only way it would make sense to build is if our time is worthless, or as a hobby project.  Maybe I'll pursue the latter when most of my workbench isn't in storage.  For now, I'm setting it aside.



Eric

nuckolls.bob(at)aeroelect
Guest

Posted: Sun May 07, 2017 10:05 am Post subject: Today's trivia dump . . .

At 12:12 PM 5/7/2017, you wrote:

  	  Quote: 	
		  --> AeroElectric-List message posted by: "Eric Page" <edpav8r(at)yahoo.com>



 Just to close the loop on this thread...



 We exchanged a few posts a couple of weeks ago about the feasibility of making a DIY spot welder for attaching battery tabs.  I've been fiddling with the idea since then and have come to the conclusion that there's little point in trying to beat the Chinese at their own game. 	


   i CA



 

 

   Bob . . .

nuckolls.bob(at)aeroelect
Guest

Posted: Sun May 07, 2017 10:18 am Post subject: Today's trivia dump . . .

At 12:12 PM 5/7/2017, you wrote:

  	  Quote: 	
		  --> AeroElectric-List message posted by: "Eric Page" <edpav8r(at)yahoo.com>



 Just to close the loop on this thread...



 We exchanged a few posts a couple of weeks ago about the feasibility of making a DIY spot welder for attaching battery tabs.  I've been fiddling with the idea since then and have come to the conclusion that there's little point in trying to beat the Chinese at their own game. 	


   Thanks for mulling the question over Eric.



   I concur. Youtube has several project videos

   on salvaging power transformers out of microwaves

   and rewinding a 100A secondary good for a few

   volts. But current control and timing was another

   matter.



   I may ask for a battery welder for Father's Day

   or something . . . not that I need another project

   right now!



   Dr. Dee and I are working with the local volunteer

   ambulance service. She got her EMT ticket a few weeks

   ago, I should finish my tests next weekend. I'm just

   driving right now. We were invited to join the

   Gyp Hills Prescribed Burn Association. We're

   going to have our own fire truck!



   We had two humongous wild fires over the past

   two years . . . largest in Kansas history.

   Could have been contained at a fraction of

   the damage with more diligence to prescribed

   burns combined with knowledgeable/willing folks

   to operate equipment.



   It's interesting to watch the expressions on

   the faces of city slickers when we tell them

   that some days we go out to fight fires . . .

   other days we go out to set fires!



 



 

 

   Bob . . .

raymondj(at)frontiernet.n
Guest

Posted: Tue May 09, 2017 12:58 pm Post subject: Today's trivia dump . . .

I guess I missed this thread earlier.  Which Chinese battery welders 

were you comparing to.  Are there any you can recommend?

Raymond Julian

Kettle River, MN

The things we admire in men, kindness and generosity, openness, honesty, 

understanding and feeling are the concomitants of failure in our system. 

And those traits we detest, sharpness, greed, acquisitiveness, meanness, 

egotism and self-interest are the traits of success. And while men 

admire the quality of the first they love the produce of the second. 

-John Steinbeck, novelist, Nobel laureate (1902-1968)

On 05/07/2017 01:03 PM, Robert L. Nuckolls, III wrote:

 	  Quote: 	
		   At 12:12 PM 5/7/2017, you wrote:

> 

>

> Just to close the loop on this thread...

>

> We exchanged a few posts a couple of weeks ago about the feasibility

> of making a DIY spot welder for attaching battery tabs.  I've been

> fiddling with the idea since then and have come to the conclusion that

> there's little point in trying to beat the Chinese at their own game.

   i CA

   Bob . . .

Eric Page

Joined: 15 Feb 2017
Posts: 245

Posted: Tue May 09, 2017 1:49 pm Post subject: Re: Today's trivia dump . . .

 	  raymondj(at)frontiernet.n wrote: 	
		  I guess I missed this thread earlier.  Which Chinese battery welders were you comparing to.  Are there any you can recommend?



Raymond Julian

Kettle River, MN 	




Bob mentioned finding this...



http://tinyurl.com/knl5wrf



...spot welder on eBay, but I don't think he has yet purchased one.  Annoyingly, I think the price has gone up a bit since he first posted the link...



Eric

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