Lead Burning plates inside old lead acid cells

I have read quite a bit about lead burning, but it does not seem appropriat e for my requirement.

From a previous life in the Middle East I inherited about 100 lead acid cel ls. I emptied the acid out, washed them thoroughly with distilled water, th en dried them in the sun, - there was lots of it! I sealed the tops and shi pped them all back to UK. From time to time I have resurrected a few to mak e up 12 volt batteries and full of sulphuric acid they performed OK and las ted a reasonable time.

A few years ago I was looking at connecting a lot together to run a more po werful inverter. but it has become more and more difficult to get sulphuric acid, health and safety don't you know.

I discovered that the electrolyte could be change to a saturated solution o f Alum (aluminium Sulphate) which is pretty docile compared to the acid an d works as well. I got a bank working OK but soon noticed a few cells were getting a very high internal resistance and finally found that the positive cells were kind of corroded so as to break off and the junction of the pos . post and the bar holding the plates.

This was nothing to do with the electrolyte as even the ones full of acid w ere the same and fresh ones from my old stock showed a very weak join on th e same place. I can only assume that the age of these cells has caused the internal corrosion in this area and it is only the Pos. plates which are af fected, the negative ones are like new and very strongly connected.

I tried my hand at soldering then together, but failed miserably and tried to clamp the fracture together in one cell but the resistance of the clampe d break, which I filed to give a clean metal to metal joint is very high an d so the discharge current is tiny compared with a good cell.

So how do you weld lead stopping it all from falling into a molten mess?

The lead sections to be re-joined are quite thick at about a quarter of an inch, but it may need to be set up in a kind of jig, or mould, to allow the lead to flow without it all melting at once.

Has anyone any ideas of how I might recover so many cells without giving up the rest of my life to the task?

Thanks for any thoughts. Oh yes I have just installed a 40 Kw 3 phase gene rator in my workshop but it is far too noisy and also I don't really need s o much horsepower It is driven by an air cooled Lister 4 cylinder diesel. I don't suppose anyone would like to swap this for a 15-20 Kw QUIET set I li ve in Norfolk and it is a bit heavy too, but I can lift it with my old JCB. I also have a couple of 30 Hp motors for sale or swap and a strange 400 c/ s or rather Hertz Yes that is not a misprint it is 3 phase 415 volts and wa s part of a frequency converter and was driven in line by the motor above. Made to computer standards by Maudsley. I can send details and photos to a nyone interested, I think there are already some on my website which is Ma ribel Eco Systems dot Co dot UK. in the old engines section the title has n o spaces by the way, no caps either.

Regards George.

Reply to
George
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Years ago I went to a welding class and the instructor was an older chap that had been welding since the days of gas welding only. He recounted his experiences lead burning the walls of an x-ray room. From his description he used a gas torch.

It was a long time ago but my recollection was that it must have been much like gas welding aluminum.

Or you could watch

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or
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Reply to
John B.

[ ... positive terminals/plates disconnecting ... ]

I fear that I can't answer this. Proably as a start, a channel which fits the bars closely and is of a material which is not likely to bond to the lead might help. Perhaps a ceramic.

[ ... ]
400 Hz (or in old terminology, cycles per second, was commonly used in two places. One, apparently is where yours was used -- power distribution for mainframe computers. It allowed physically smaller local power supplies to be distributed through the system.

The other, and where I am more familiar with it, is for electronics in aircraft. 400 Hz transformers are a lot lighter than 60 Hz ones capable of transmitting the same power, so almost everything in aircraft (military and larger civilian at least) is made to run from 400 Hz. And it is typically 115 V three phase to drive the rotors in gyroscopes for inertial navigation systems, and to make sure that they rotate they right direction. I have a rotary converter which takes in 28 VDC at perhaps 20 Amps or more, and produces the 115 V 400 Hz 3 phase. It also produces more audio noise than I like. :-)

I'm experimenting with instruments (some of which are normally driven from the inertial navigation system mentioned above), but the instruments only need single phase 115 VAC for internal power, and signals from synchros (also called Selsyns) which are sort of three phase, but not really at power levels. The actual phase relationship of the three leads, and the relative voltages, carry angular information.

I've recently gotten the necessary parts to drive a Variac (variable autotransformer) made for 400 Hz with 20 VAC out of an audio power amplifier, and boost it to the needed voltages -- 120 VAC from another tap on the winding, and 26 VAC from the wiper.

Enjoy, DoN.

Reply to
DoN. Nichols

You need an R-2800 to mask the converter's noise.

-jsw

Reply to
Jim Wilkins

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Reply to
Jim Wilkins

I guess that it would -- but is a bit out of my budget, and probably the town would not let me run it very long. :-)

Enjoy, DoN.

Reply to
DoN. Nichols

The operating cost for some of those old warbirds works out to around a dollar per second.

Reply to
Jim Wilkins

I loved the sound of those A-1 Skyraiders at NKP!

Reply to
Phil Kangas

Like this?

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Nice!

Reply to
Larry Jaques

Dad was a crop duster (in addition to rice, cows, and making levee rollers). We ran R-985's on Super Ag Cats back then. I can still remember the sounds of one catching and firing up. He'd often have me or my brother run one at 1000 rpm to warm up, sitting with our feet on the brakes. Especially after the brake lock failed on one and it rolled forward until the prop hit a full oil drum. It threw that drum about 50 yards, cut almost in two with big spiral slices. It made quite a mess.

Pete Keillor

Reply to
Pete Keillor

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Reply to
Jim Wilkins

Whew! What'd the replacement prop blades cost?

Wow, with a 5x5" bore/stroke, she's not a petite engine.

Those 35 specialty tools used on those are likely -expensive- dinosaur teeth, wot? I think I'll DL and read that entire manual for kicks.

It's too bad I graduated from high school directly into alcoholism. Being an Air Force brat, I loved flying and would have chosen an aviation tech school and become an aircraft mechanic and pilot rather than an auto mechanic, but I didn't want to join the military, either. July 10th, I'll be 32 years sober, Crom willing.

Reply to
Larry Jaques

If you really want to hear the round engines talk, you need to be in the co ckpit of a DC-6A on a cold day in AL. Doing engine runs after a few jug cha nges. The procedure after breakin was to take all 4 to max. takeoff power d ry, and then throw all 4 water/meth ganged switches on the eyebrow panel. F irst time I witnessed it, it was a schock. It was rocking in the chocks and the whole aircraft shuddered. What mechanical music that was. P&W wrote th e book on radials with the 2800. When I went to Boeing 767 school in Seattl e, the instructors had deep respect for P&W. Called them the Pratt Iron Wo rks in deference to their tough engines. My son is a PhD aerospace enginee r and works for Pratt now designing mil. engines. And that's metalworking c ontent.

Reply to
Garrett Fulton

Thanks, I'll download that. I've seen a running 1/5 scale model. I don't know if it had the supercharger.

Pete

Reply to
Pete Keillor

Way down on my to-do list:

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-jsw

Reply to
Jim Wilkins

Fantastic! I used to have (lost in a move) plans for a 1/5 scale A-26. I initially got into machining from 1. workplace envy (I designed stuff, the shop got to build) and 2. the desire, unrealistic though it might be, to power that model with actual radials. If not

18 cyl (your R-2800), then at least 9.

Way down on the list is a good description.

Pete

Reply to
Pete Keillor

The full sized '985 had a gear driven centrifugal supercharger as did many radial engines. Perhaps more to ensure even fuel distribution to the radial cylinders than to generate more power. If the 1/5th scale model didn't then it's lower cylinders likely ran rich while the upper cylinders ran lean :-)

Reply to
John B.

It was a small fraction of my excuse to buy this 6-jaw chuck:

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Yesterday I tapped broom threads

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in 1/2" plastic electrical conduit to make a tool that fits on a painting extension pole. Neither a 3-jaw nor that 6-jaw would grip well enough to resist the tapping torque and I had to use a 27/32" collet. My main excuse to buy the 6-jaw was to chuck tubing larger than 5C collet size.

That chuck has a gap in its gripping range. It doesn't open much beyond 1" before the jaws slip off the scroll and the minimum ID it will fit is 1.310"

The tapped hole was too small to screw on by hand until I heat-softened the PVC. Threads in oak fit better so the plastic must have deformed.

-jsw

Reply to
Jim Wilkins

I did something similar, only I single pointed it in aluminum. Cut it upside down to have the bit leaving the hole. I had to modify the acme profile some to get the handle to spin in. It was for an adapter to allow me to get the engine flush bracket onto my outboard while hanging over the transom (it was in a marina on a lift at the time).

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Beat cracking the cartilage in my ribs, which I did twice before making it.

That tap would have been handy.

Pete

Reply to
Pete Keillor

It was probably in there. He even had a miniature of the PW emblem on the oil sump between the bottom two cylinders.

Pete Keillor

Reply to
Pete Keillor

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