[Boatanchors] Electrolytic Reforming Time

Geoff geoffrey at jeremy.mv.com
Sun Jan 1 11:20:45 EST 2012 

What gets this old goats goat is that Im often the recipient of these 
meltdowns and have to repair the mess. Its not just electrolytics that cause 
rectifiers and transformers to fail. At times only a single paper cap can do 
it (or the cumulative effect of several) especially if at the grid or plate 
of an audio tube.

It really is time to just ignore the die hards as they will soon fade away 
in a column of smoke.

Carl
KM1H


----- Original Message ----- 
From: "Bob Jackson" <bob at nofrowns.net>
To: "lee" <pulsarxp at embarqmail.com>; <boatanchors at mailman.qth.net>
Sent: Saturday, December 31, 2011 8:35 PM
Subject: Re: [Boatanchors] Electrolytic Reforming Time


> Lee -
>
> I'm somewhat puzzled and even a bit amused that this particular thread has
> gone on for so long. At the risk of protracting it even further ...
>
> I, too, agree with you and Carl. I've even seen "partial" replacements 
> where
> one or two sections of an old multi-section cap have been reformed and 
> left
> in circuit, and the only one(s) that "can't-get-it-to-reform" replaced.
> Nonsense in the highest degree. I suppose putting new caps inside the old
> can (or tube - melt out the wax, put in the new caps and refill with wax) 
> to
> preserve the "look and feel" of the original perhaps may have some
> anal-retentive cosmetic merit. However, considering the time and bother to
> achieve such correctly, it's not something I'd ever do. (I do routinely
> leave the vertical can cap on the top of the chassis in place (but wholly
> disconnected) for cosmetic purposes while the modern replacements remain
> hidden underneath.)
>
> Moreover, reforming/reusing old caps, in my mind, doesn't show respect for
> the equipment. If the thing is worth restoring in the first place, then 
> it's
> worth bringing it back to life not only to its original performance but 
> also
> its reliability and design longevity. Recall - most if not all of these
> "boats" weren't made under the marketing philosophy of "designed 
> obsolesce"
> that's prevalent today. (How many iPhones does it take to change a P/L
> report?) It seems to me that "reforming", etc. is more in the  realm of
> "gee whiz, look what I can do" much like the gratuitous, over use of
> computer-generated graphics in many of today's movies, i.e. a bit of a 
> "show
> off", ego trip for the person at the controls.
>
> Still, at the end of the day, we each have our own, particular (perhaps 
> even
> peculiar) "operating parameters" that govern our behavior as we pursue 
> this
> hobby. Clearly, our time and other resources, along with our goals and
> values, are our own personal concern, and no one else's.
>
> 73 to all,
>
> Bob  AG5X
>
> ----- Original Message ----- 
> From: "lee" <pulsarxp at embarqmail.com>
> To: <boatanchors at mailman.qth.net>
> Sent: Saturday, December 31, 2011 6:48 PM
> Subject: Re: [Boatanchors] Electrolytic Reforming Time
>
>
>> Carl and others,
>>
>> I agree, using old electrolytics even when reformed is foolishness.   My
>> suggestion to those doing so is, right after installation of a 50 year 
>> old
>> cap which was designed to last around 6 years is to immediately buy an
>> insurance policy on your apparatus and then make a copy of this e-mail.
>> When the thing blows up in your face, read the warning e-mail, and please
>> don't wine on the list when it fails, and it will fail.
>>
>> To be honest I am beginning to wonder why I belong to any list knowingly
>> suggesting this type of foolishness.  As a learning experience, reforming
>> is
>> just fine or used in an emergency which I cannot see happening with 
>> anyone
>> on this list.  Doing so for some old piece of junk and not caring if the
>> thing blows up may be one other exception.  For the life of me,  I cannot
>> understand why someone would want to install a time bomb in his pet
>> historical project, take the time to do it, and at the same time avoid
>> using
>> a modern, fresh, and better made capacitor which today costs very little.
>> You can rebuild an old three section can electrolytic for $5-$10 or buy
>> 450
>> volt axials for less then $5 each.
>>
>> You won't find me playing Russian Rue let with my old equipment using 
>> this
>> bad practice.
>>
>> Lee, w0vt
>>
>>
>> -----Original Message----- 
>> From: Geoff
>> Sent: Saturday, December 31, 2011 4:20 PM
>> To: W9RAN at oneradio.net ; boatanchors at mailman.qth.net
>> Subject: Re: [Boatanchors] Electrolytic Reforming Time
>>
>> Id tend to flip those percentages to maybe 10-20% and thats with very 
>> high
>> quality caps and some fairly late ones.
>>
>> It seems to me that we only hear from the same "reformers" over and over
>> and
>> the failed ones are very silent while licking their wounds and searching
>> for
>> new transformers or a rewinder.
>>
>> Just my $.02
>>
>> Carl
>> KM1H
>>
>>
>>
>> ----- Original Message ----- 
>> From: "Robert Nickels" <ranickel at comcast.net>
>> To: <boatanchors at mailman.qth.net>
>> Sent: Saturday, December 31, 2011 4:32 PM
>> Subject: Re: [Boatanchors] Electrolytic Reforming Time
>>
>>
>>> On 12/30/2011 11:50 PM, Phil wrote:
>>>> So, it doesn't pay to take any chances with those 'lytics.
>>> I agree with all that's been said but would just add that this business
>>> of "bringing it up slowly on a variac" should be relegated to the urban
>>> legends file.  It's better than just applying full AC power, but is
>>> still guesswork.   The only way to properly reform an electrolytic -
>>> regardless of age - is to limit (and measure) the amount of current
>>> being applied to attempt to "reform" the anode oxide layer that was
>>> "formed" at the factory when the cap was manufactured.
>>>
>>> A good description of how the aluminum electrolytic capacitor works can
>>> be found here:
>>> http://www.elna-america.com/tech_al_principles.php
>>>
>>> And here's a good reference for how to reform capacitors properly as
>>> well as some alternatives:
>>> http://www.nmr.mgh.harvard.edu/~reese/electrolytics/
>>>
>>> I prefer to measure and limit the current to about 5 ma while the oxide
>>> layer is reforming; trying to do the job by simply cranking up a variac
>>> every so often might work some of the time, but is like tuning your rig
>>> while blindfolded.
>>>
>>> I generally just replace electroyltics that are  cheap and readily
>>> available and attempt to reform those that aren't.  I think most
>>> "reformers" find the process can restore 80-90% of old caps when done
>>> right, without fear of explosions or failure.
>>>
>>> 73, Bob W9RAN
>>> ______________________________________________________________
>>> Boatanchors mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/boatanchors
>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:Boatanchors at mailman.qth.net
>>>
>>> List Administrator: Duane Fischer, W8DBF
>>> ** For Assistance: dfischer at usol.com **
>>>
>>>
>>> This list hosted by: http://www.qsl.net
>>> Please help support this email list: http://www.qsl.net/donate.html
>>>
>>>
>>> -----
>>> No virus found in this message.
>>> Checked by AVG - www.avg.com
>>> Version: 10.0.1416 / Virus Database: 2109/4114 - Release Date: 12/31/11
>>>
>>
>> ______________________________________________________________
>> Boatanchors mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/boatanchors
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:Boatanchors at mailman.qth.net
>>
>> List Administrator: Duane Fischer, W8DBF
>> ** For Assistance: dfischer at usol.com **
>>
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>>
>> ______________________________________________________________
>> Boatanchors mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/boatanchors
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:Boatanchors at mailman.qth.net
>>
>> List Administrator: Duane Fischer, W8DBF
>> ** For Assistance: dfischer at usol.com **
>>
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>
> ______________________________________________________________
> Boatanchors mailing list
> Home: http://mailman.qth.net/mailman/listinfo/boatanchors
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Boatanchors at mailman.qth.net
>
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer at usol.com **
>
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 10.0.1416 / Virus Database: 2109/4116 - Release Date: 01/01/12
>

More information about the Boatanchors mailing list