"Larry W" wrote
>
> "And there were folks who killed themselves this way on a regular basis."
>
>
> I just LOVE that line!
>
>
Well........, when you are working with high voltage and/or current, you
have to be careful. And the message was pounded home by instructors, many
of them ex-military, who had some gory stories to tell.
We had an expression in that school. If somebody got a shock, we said they
got "bit". And often when this "biting" took place, there was some yelling
and screaming. At that point all classes came to a stop for a moment. The
instructor would point in the general direction of the scream and say
something to the effect that another person just got bit.
I made it all the way through a year of that school without getting bit.
But two days before I graduated, while working on a peice of test equipment
I picked up at a garage sale, I got bit. I got bit big time. I still have a
dead spot on my right index finger from that. Rumors were that that scream
was heard down the block.
J. Clarke wrote:
> It's sold in the US under the "Coleman" brand and you can find another
> review at
> http://www.popularmechanics.com/blogs/technology_news/4223118.html.
> According to them it can screw in 22 fasteners under the same
> conditions that a Skil IXO can screw in 37.
>
> The thing that fascinates me about this particular tool is that
> capacitor technology has developed to the point that such a tool _can_
> be made.
That impresses me as well. If this is like most new things, it starts
off slow and progresses into a battery killer. The sooner the better I say.
My favorite drill is "almost" a B&D versa drill. It fits my hand
perfectly, and is perfectly balanced and super light weight. It seems
B&D quit making them. The problem is the two versa batteries suck and
they don't seem to last worth diddly. I've gone through about 4 sets
and have about given up on it, but still, the drill is the nicest
battery powered drill I have, except for the battery problem. If they
made lithium-ion replacement batteries for it I would by them. Better
would be the same drill with capacitor technology, but it would have to
be a little more powerful than the GM thing. Hopefully thats in our future.
I have a couple of capacitor flashlights you shake to charge up and I
love them.
They always work unlike the damed battery lights that never work when
you need them...
--
Jack
http://jbstein.com
On Jul 2, 6:09=A0pm, "J. Clarke" <[email protected]> wrote:
> Limp Arbor wrote:
> > On Jul 2, 2:35 pm, "xcz" <[email protected]> wrote:
> >>http://www.onlinetoolreviews.com/reviews/gmcfastcellscrewdrivers.htm
>
> >> Enjoy.
>
> >> --
> >> --
> >> Regards,
>
> >> Dean Bielanowski
> >> Editor
> >> OnlineToolReviews.comhttp://www.onlinetoolreviews.com
> >> Over 190+ free tool reviews online!
>
> > so I can buy a GMC screwdriver for $100 (roughly 3.5 times the cost
> > of
> > a B&D VersaPak) and trust that the capacitor will never go bad?
> >http://www.redboxhardware.com.au/index.aspx?page=3Dproducts&catid=3D2&sc=
i...
>
> > vs $29 B&D
> >http://www.amazon.com/Black-Decker-VP800-Black%2526-Screwdriver/dp/B0...
>
> > I'll skip both and stick with a screwdriver that has a 'real'
> > lifetime
> > guarantee (including the battery)
> >http://buy1.snapon.com/catalog/item.asp?search=3Dtrue&item_ID=3D65&PartN=
o...
> > or
> >http://www.garrettwade.com/jump.jsp?itemType=3DPRODUCT&RS=3D1&itemID=3D1=
125...
>
> Do your "lifetime guarantee" tools charge in less than a minute?
>
No, takes about 8 hours but can go all day and then some.
"Lee Michaels" <[email protected]> wrote in message
news:[email protected]...
>
> "J. Clarke" <[email protected]> wrote
>>
>> The thing that fascinates me about this particular tool is that
>> capacitor technology has developed to the point that such a tool _can_
>> be made.
>>
>>
> Snip
>
> I think this technology is great though. I am just wondering when the
> charge gets big enough to become dangerous. And if it is enough power to
> do many of the jobs now done by portable tools using current battery
> technology. The nearly instant charge thing is really interesting. That
> feature is definitely different. It could easily change some work habits
> if it proves to work well.
The instant charge thing is really not too new. Older cars with mechanical
distributors had a capacitor that signaled the coil to discharge and would
charge and discharge 8 times per revolution of the distributor rotor on a
V8. At an idle, 600 RPM, that capcitor would charge and discharge 2400
times per minute or 40 times per second. That sorta backs up the theory
that the battery in the GMC driver can go through 500,000 cycles.
>
> I have this image in my mind of a capaciter driven car. Can you imagine
> the charge that thing would take? And how many people would be
> electrocuted if the thing got into a wreck? One bright thought on that
> idea is that you could easily incorporate a deadly thief deterrent into
> its design.
That may be a feasible thought, I was thinking about that last night. The
electric cars use a Lithium style battery that came on strong about the same
time the Lith ion batteries became widely available for tools. Voltage
should not be any more of a problem with the capacitor type battery, the
current battery driven car batteries deliver in excess of 400 volts and they
like tool batteries are being recharged in as little as 15 minutes. I would
think that the capacitor type battery would charge even faster.
I'm unimpressed.
I went to the GMC website and found their so called specifications to be nothing more
than an advertisement for the product. Example: "High Shelf Life - Fully charged on
it's own, the Flashcell will remain charged almost indefinitely". The phrase "almost
indefinitely" is pure marketing speak. In your review you mentioned the relative
self discharge rates for L-ion and NiCd but not a word about the GMC.
Fast charging is great but how long does a charge last? How many screws will it
drive?
Chemical batteries have a shallow voltage discharge curve until the charge is almost
depleted then it falls rapidly. A capacitors voltage immediately, and linearly,
falls as charge is pulled out of it. At half charge there is half the initial
voltage which will have a devastating effect on the torque produced by the driver.
There is not a word about this on the GMC website. If the user has to recharge after
only using 10% of the charge this would be a big negative.
Art
In article <[email protected]>,
[email protected] says...
>
> "Lee Michaels" <[email protected]> wrote in message
> news:[email protected]...
> >
> > "J. Clarke" <[email protected]> wrote
> >>
> >> The thing that fascinates me about this particular tool is that
> >> capacitor technology has developed to the point that such a tool _can_
> >> be made.
> >>
> >>
> > Snip
>
> >
> > I think this technology is great though. I am just wondering when the
> > charge gets big enough to become dangerous. And if it is enough power to
> > do many of the jobs now done by portable tools using current battery
> > technology. The nearly instant charge thing is really interesting. That
> > feature is definitely different. It could easily change some work habits
> > if it proves to work well.
>
> The instant charge thing is really not too new. Older cars with mechanical
> distributors had a capacitor that signaled the coil to discharge and would
> charge and discharge 8 times per revolution of the distributor rotor on a
> V8. At an idle, 600 RPM, that capcitor would charge and discharge 2400
> times per minute or 40 times per second. That sorta backs up the theory
> that the battery in the GMC driver can go through 500,000 cycles.
>
>
>
> >
> > I have this image in my mind of a capaciter driven car. Can you imagine
> > the charge that thing would take? And how many people would be
> > electrocuted if the thing got into a wreck? One bright thought on that
> > idea is that you could easily incorporate a deadly thief deterrent into
> > its design.
>
> That may be a feasible thought, I was thinking about that last night. The
> electric cars use a Lithium style battery that came on strong about the same
> time the Lith ion batteries became widely available for tools. Voltage
> should not be any more of a problem with the capacitor type battery, the
> current battery driven car batteries deliver in excess of 400 volts and they
> like tool batteries are being recharged in as little as 15 minutes. I would
> think that the capacitor type battery would charge even faster.
The stored energy in a capacitor is 1/2C*V^2, so the higher the
voltage the more the charge stored. As has been pointed out here
before, the voltage will go down linearly as the capacitor
discharges. The power into a load (resistor) will go down by the
square of the charge pulled out. It *might* be able to be charged
faster, but all that energy still has to make into the "cell". High
currents aren't friendly either. Whatever you do, you're storing
significant energy and it will turn to fire if let loose.
In short, ;-) count me skeptical.
--
Keith
In article <[email protected]>, [email protected]
says...
> Lee Michaels wrote:
> > "J. Clarke" <[email protected]> wrote
> >>
> >> The thing that fascinates me about this particular tool is that
> >> capacitor technology has developed to the point that such a tool
> >> _can_ be made.
> >>
> >>
> > Same here.
> >
> > I remember from electronics school, way back when the big cathode
> > ray
> > tube (TV's) was a field of study. And how we had to isolate them
> > with
> > special transformers and ground it before working. Otherwise, it
> > would kill you. Because it was a massive capaciter that stored
> > enough
> > charge to zap your heart into the great beyond. And there were
> > folks
> > who killed themselves this way on a regular basis.
> >
> > I think this technology is great though. I am just wondering when
> > the
> > charge gets big enough to become dangerous. And if it is enough
> > power to do many of the jobs now done by portable tools using
> > current
> > battery technology. The nearly instant charge thing is really
> > interesting. That feature is definitely different. It could easily
> > change some work habits if it proves to work well.
> >
> > I have this image in my mind of a capaciter driven car. Can you
> > imagine the charge that thing would take? And how many people would
> > be electrocuted if the thing got into a wreck? One bright thought
> > on
> > that idea is that you could easily incorporate a deadly thief
> > deterrent into its design.
>
> A while back I picked up a 5 farad supercapacitor just to dink with.
> The thing's about the diameter of a C cell and maybe a third the
> height. Turns out that it's current delivery is limited due to a
> fairly high internal resistance. That takes a lot of the danger out
> of it. It's my understanding that when overvolted sufficiently they
> die peacefully never to charge again--I never tried that with mine
> though.
>
> Remember, that CRT is charged to something in excess of 18KV--the high
> voltage is what makes it dangerous. A supercapacitor can't handle
> that kind of voltage.
The energy stored is what makes it dangerous. The 18kV makes the
energy stored 4,000,000 times that of a 9V capacitor of the same
capacitance.
--
Keith
In article <[email protected]>, [email protected]
says...
> krw wrote:
> > In article <[email protected]>, [email protected]
> > says...
> >> Lee Michaels wrote:
> >>> "J. Clarke" <[email protected]> wrote
> >>>>
> >>>> The thing that fascinates me about this particular tool is that
> >>>> capacitor technology has developed to the point that such a tool
> >>>> _can_ be made.
> >>>>
> >>>>
> >>> Same here.
> >>>
> >>> I remember from electronics school, way back when the big cathode
> >>> ray
> >>> tube (TV's) was a field of study. And how we had to isolate them
> >>> with
> >>> special transformers and ground it before working. Otherwise, it
> >>> would kill you. Because it was a massive capaciter that stored
> >>> enough
> >>> charge to zap your heart into the great beyond. And there were
> >>> folks
> >>> who killed themselves this way on a regular basis.
> >>>
> >>> I think this technology is great though. I am just wondering when
> >>> the
> >>> charge gets big enough to become dangerous. And if it is enough
> >>> power to do many of the jobs now done by portable tools using
> >>> current
> >>> battery technology. The nearly instant charge thing is really
> >>> interesting. That feature is definitely different. It could
> >>> easily
> >>> change some work habits if it proves to work well.
> >>>
> >>> I have this image in my mind of a capaciter driven car. Can you
> >>> imagine the charge that thing would take? And how many people
> >>> would
> >>> be electrocuted if the thing got into a wreck? One bright thought
> >>> on
> >>> that idea is that you could easily incorporate a deadly thief
> >>> deterrent into its design.
> >>
> >> A while back I picked up a 5 farad supercapacitor just to dink
> >> with.
> >> The thing's about the diameter of a C cell and maybe a third the
> >> height. Turns out that it's current delivery is limited due to a
> >> fairly high internal resistance. That takes a lot of the danger
> >> out
> >> of it. It's my understanding that when overvolted sufficiently
> >> they
> >> die peacefully never to charge again--I never tried that with mine
> >> though.
> >>
> >> Remember, that CRT is charged to something in excess of 18KV--the
> >> high voltage is what makes it dangerous. A supercapacitor can't
> >> handle that kind of voltage.
> >
> > The energy stored is what makes it dangerous. The 18kV makes the
> > energy stored 4,000,000 times that of a 9V capacitor of the same
> > capacitance.
>
> So how many people died of electrocution from 2.7v sources in the past
> 100 years?
How do you propose to store useful energy on a capacitor at 2.7V?
--
Keith
In article <[email protected]>, [email protected]
says...
> krw wrote:
> > In article <[email protected]>, [email protected]
> > says...
> >> krw wrote:
> >>> In article <[email protected]>, [email protected]
> >>> says...
> >>>> Lee Michaels wrote:
> >>>>> "J. Clarke" <[email protected]> wrote
> >>>>>>
> >>>>>> The thing that fascinates me about this particular tool is that
> >>>>>> capacitor technology has developed to the point that such a
> >>>>>> tool
> >>>>>> _can_ be made.
> >>>>>>
> >>>>>>
> >>>>> Same here.
> >>>>>
> >>>>> I remember from electronics school, way back when the big
> >>>>> cathode
> >>>>> ray
> >>>>> tube (TV's) was a field of study. And how we had to isolate them
> >>>>> with
> >>>>> special transformers and ground it before working. Otherwise, it
> >>>>> would kill you. Because it was a massive capaciter that stored
> >>>>> enough
> >>>>> charge to zap your heart into the great beyond. And there were
> >>>>> folks
> >>>>> who killed themselves this way on a regular basis.
> >>>>>
> >>>>> I think this technology is great though. I am just wondering
> >>>>> when
> >>>>> the
> >>>>> charge gets big enough to become dangerous. And if it is enough
> >>>>> power to do many of the jobs now done by portable tools using
> >>>>> current
> >>>>> battery technology. The nearly instant charge thing is really
> >>>>> interesting. That feature is definitely different. It could
> >>>>> easily
> >>>>> change some work habits if it proves to work well.
> >>>>>
> >>>>> I have this image in my mind of a capaciter driven car. Can you
> >>>>> imagine the charge that thing would take? And how many people
> >>>>> would
> >>>>> be electrocuted if the thing got into a wreck? One bright
> >>>>> thought
> >>>>> on
> >>>>> that idea is that you could easily incorporate a deadly thief
> >>>>> deterrent into its design.
> >>>>
> >>>> A while back I picked up a 5 farad supercapacitor just to dink
> >>>> with.
> >>>> The thing's about the diameter of a C cell and maybe a third the
> >>>> height. Turns out that it's current delivery is limited due to a
> >>>> fairly high internal resistance. That takes a lot of the danger
> >>>> out
> >>>> of it. It's my understanding that when overvolted sufficiently
> >>>> they
> >>>> die peacefully never to charge again--I never tried that with
> >>>> mine
> >>>> though.
> >>>>
> >>>> Remember, that CRT is charged to something in excess of 18KV--the
> >>>> high voltage is what makes it dangerous. A supercapacitor can't
> >>>> handle that kind of voltage.
> >>>
> >>> The energy stored is what makes it dangerous. The 18kV makes the
> >>> energy stored 4,000,000 times that of a 9V capacitor of the same
> >>> capacitance.
> >>
> >> So how many people died of electrocution from 2.7v sources in the
> >> past 100 years?
> >
> > How do you propose to store useful energy on a capacitor at 2.7V?
>
> "Propose"? I don't need to "propose" anything, we're discussing a
> commercial off the shelf product.
No, we're talking about someone's wet dream.
> Perhaps you aren't aware that the capacitance of a CRT is measured in
> single-digit nanofarads, the capacitance of ultracapacitors is
> measured in hundreds of farads.
Perhaps you've never heard that 4,000,000 is a *BIG* number.
--
Keith
In article <[email protected]>, [email protected]
says...
> krw wrote:
> > In article <[email protected]>, [email protected]
> > says...
> >> krw wrote:
> >>> In article <[email protected]>, [email protected]
> >>> says...
> >>>> krw wrote:
> >>>>> In article <[email protected]>,
> >>>>> [email protected]
> >>>>> says...
> >>>>>> Lee Michaels wrote:
> >>>>>>> "J. Clarke" <[email protected]> wrote
> >>>>>>>>
> >>>>>>>> The thing that fascinates me about this particular tool is
> >>>>>>>> that
> >>>>>>>> capacitor technology has developed to the point that such a
> >>>>>>>> tool
> >>>>>>>> _can_ be made.
> >>>>>>>>
> >>>>>>>>
> >>>>>>> Same here.
> >>>>>>>
> >>>>>>> I remember from electronics school, way back when the big
> >>>>>>> cathode
> >>>>>>> ray
> >>>>>>> tube (TV's) was a field of study. And how we had to isolate
> >>>>>>> them
> >>>>>>> with
> >>>>>>> special transformers and ground it before working. Otherwise,
> >>>>>>> it
> >>>>>>> would kill you. Because it was a massive capaciter that stored
> >>>>>>> enough
> >>>>>>> charge to zap your heart into the great beyond. And there
> >>>>>>> were
> >>>>>>> folks
> >>>>>>> who killed themselves this way on a regular basis.
> >>>>>>>
> >>>>>>> I think this technology is great though. I am just wondering
> >>>>>>> when
> >>>>>>> the
> >>>>>>> charge gets big enough to become dangerous. And if it is
> >>>>>>> enough
> >>>>>>> power to do many of the jobs now done by portable tools using
> >>>>>>> current
> >>>>>>> battery technology. The nearly instant charge thing is really
> >>>>>>> interesting. That feature is definitely different. It could
> >>>>>>> easily
> >>>>>>> change some work habits if it proves to work well.
> >>>>>>>
> >>>>>>> I have this image in my mind of a capaciter driven car. Can
> >>>>>>> you
> >>>>>>> imagine the charge that thing would take? And how many people
> >>>>>>> would
> >>>>>>> be electrocuted if the thing got into a wreck? One bright
> >>>>>>> thought
> >>>>>>> on
> >>>>>>> that idea is that you could easily incorporate a deadly thief
> >>>>>>> deterrent into its design.
> >>>>>>
> >>>>>> A while back I picked up a 5 farad supercapacitor just to dink
> >>>>>> with.
> >>>>>> The thing's about the diameter of a C cell and maybe a third
> >>>>>> the
> >>>>>> height. Turns out that it's current delivery is limited due to
> >>>>>> a
> >>>>>> fairly high internal resistance. That takes a lot of the
> >>>>>> danger
> >>>>>> out
> >>>>>> of it. It's my understanding that when overvolted sufficiently
> >>>>>> they
> >>>>>> die peacefully never to charge again--I never tried that with
> >>>>>> mine
> >>>>>> though.
> >>>>>>
> >>>>>> Remember, that CRT is charged to something in excess of
> >>>>>> 18KV--the
> >>>>>> high voltage is what makes it dangerous. A supercapacitor
> >>>>>> can't
> >>>>>> handle that kind of voltage.
> >>>>>
> >>>>> The energy stored is what makes it dangerous. The 18kV makes
> >>>>> the
> >>>>> energy stored 4,000,000 times that of a 9V capacitor of the same
> >>>>> capacitance.
> >>>>
> >>>> So how many people died of electrocution from 2.7v sources in the
> >>>> past 100 years?
> >>>
> >>> How do you propose to store useful energy on a capacitor at 2.7V?
> >>
> >> "Propose"? I don't need to "propose" anything, we're discussing a
> >> commercial off the shelf product.
> >
> > No, we're talking about someone's wet dream.
>
> I'm sorry, but if it's in stock at Digi-Key it's not a "wet dream".
The existence of a "supercapacitor" isn't the issue.
> >> Perhaps you aren't aware that the capacitance of a CRT is measured
> >> in
> >> single-digit nanofarads, the capacitance of ultracapacitors is
> >> measured in hundreds of farads.
> >
> >
> > Perhaps you've never heard that 4,000,000 is a *BIG* number.
>
> So divide the capacitance of a d-cell ultracapacitor by the
> capacitance of a CRT and see what you get. I think you'll find that
> it's a *BIGGER* number.
The energy stored in a "supercapactior" is *not* as much as stored
in the second anode circuit of a TV (it's a lot more than just the
glass).
--
Keith
"J. Clarke" <[email protected]> wrote in message
news:[email protected]...
> Limp Arbor wrote:
>> On Jul 2, 2:35 pm, "xcz" <[email protected]> wrote:
>>> http://www.onlinetoolreviews.com/reviews/gmcfastcellscrewdrivers.htm
>>>
>>> Enjoy.
>>>
>>> --
>>> --
>>> Regards,
>>>
>> I'll skip both and stick with a screwdriver that has a 'real'
>> lifetime
>> guarantee (including the battery)
>> http://buy1.snapon.com/catalog/item.asp?search=true&item_ID=65&PartNo=SSDMR4B&group_id=702&supersede=&store=snapon-store&tool=all
>> or
>> http://www.garrettwade.com/jump.jsp?itemType=PRODUCT&RS=1&itemID=112553&keyword=08C03.01
>
> Do your "lifetime guarantee" tools charge in less than a minute?
Mine take at least 8 hours and sometimes a cold beer to recharge
On Jul 4, 10:51=A0pm, "J. Clarke" <[email protected]> wrote:
> krw wrote:
> > In article <[email protected]>, [email protected]
> > says...
> >> krw wrote:
> >>> In article <[email protected]>, [email protected]
> >>> says...
> >>>> krw wrote:
> >>>>> In article <[email protected]>,
> >>>>> [email protected]
> >>>>> says...
> >>>>>> krw wrote:
> >>>>>>> In article <[email protected]>,
> >>>>>>> [email protected]
> >>>>>>> says...
> >>>>>>>> Lee Michaels wrote:
> >>>>>>>>> "J. Clarke" <[email protected]> wrote
>
> >>>>>>>>>> The thing that fascinates me about this particular tool is
> >>>>>>>>>> that
> >>>>>>>>>> capacitor technology has developed to the point that such a
> >>>>>>>>>> tool
> >>>>>>>>>> _can_ be made.
>
> >>>>>>>>> Same here.
>
> >>>>>>>>> I remember from electronics school, way back when the big
> >>>>>>>>> cathode
> >>>>>>>>> ray
> >>>>>>>>> tube (TV's) was a field of study. And how we had to isolate
> >>>>>>>>> them
> >>>>>>>>> with
> >>>>>>>>> special transformers and ground it before working.
> >>>>>>>>> Otherwise,
> >>>>>>>>> it
> >>>>>>>>> would kill you. Because it was a massive capaciter that
> >>>>>>>>> stored
> >>>>>>>>> enough
> >>>>>>>>> charge to zap your heart into the great beyond. =A0And there
> >>>>>>>>> were
> >>>>>>>>> folks
> >>>>>>>>> who killed themselves this way on a regular basis.
>
> >>>>>>>>> I think this technology is great though. =A0I am just
> >>>>>>>>> wondering
> >>>>>>>>> when
> >>>>>>>>> the
> >>>>>>>>> charge gets big enough to become dangerous. =A0And if it is
> >>>>>>>>> enough
> >>>>>>>>> power to do many of the jobs now done by portable tools
> >>>>>>>>> using
> >>>>>>>>> current
> >>>>>>>>> battery technology. =A0The nearly instant charge thing is
> >>>>>>>>> really
> >>>>>>>>> interesting. =A0That feature is definitely different. =A0It
> >>>>>>>>> could
> >>>>>>>>> easily
> >>>>>>>>> change some work habits if it proves to work well.
>
> >>>>>>>>> I have this image in my mind of a capaciter driven car. Can
> >>>>>>>>> you
> >>>>>>>>> imagine the charge that thing would take? And how many
> >>>>>>>>> people
> >>>>>>>>> would
> >>>>>>>>> be electrocuted if the thing got into a wreck? =A0One bright
> >>>>>>>>> thought
> >>>>>>>>> on
> >>>>>>>>> that idea is that you could easily incorporate a deadly
> >>>>>>>>> thief
> >>>>>>>>> deterrent into its design.
>
> >>>>>>>> A while back I picked up a 5 farad supercapacitor just to
> >>>>>>>> dink
> >>>>>>>> with.
> >>>>>>>> The thing's about the diameter of a C cell and maybe a third
> >>>>>>>> the
> >>>>>>>> height. =A0Turns out that it's current delivery is limited due
> >>>>>>>> to
> >>>>>>>> a
> >>>>>>>> fairly high internal resistance. =A0That takes a lot of the
> >>>>>>>> danger
> >>>>>>>> out
> >>>>>>>> of it. =A0It's my understanding that when overvolted
> >>>>>>>> sufficiently
> >>>>>>>> they
> >>>>>>>> die peacefully never to charge again--I never tried that with
> >>>>>>>> mine
> >>>>>>>> though.
>
> >>>>>>>> Remember, that CRT is charged to something in excess of
> >>>>>>>> 18KV--the
> >>>>>>>> high voltage is what makes it dangerous. =A0A supercapacitor
> >>>>>>>> can't
> >>>>>>>> handle that kind of voltage.
>
> >>>>>>> The energy stored is what makes it dangerous. =A0The 18kV makes
> >>>>>>> the
> >>>>>>> energy stored 4,000,000 times that of a 9V capacitor of the
> >>>>>>> same
> >>>>>>> capacitance.
>
> >>>>>> So how many people died of electrocution from 2.7v sources in
> >>>>>> the
> >>>>>> past 100 years?
>
> >>>>> How do you propose to store useful energy on a capacitor at
> >>>>> 2.7V?
>
> >>>> "Propose"? =A0I don't need to "propose" anything, we're discussing
> >>>> a
> >>>> commercial off the shelf product.
>
> >>> No, we're talking about someone's wet dream.
>
> >> I'm sorry, but if it's in stock at Digi-Key it's not a "wet dream".
>
> > The existence of a "supercapacitor" isn't the issue.
>
> >>>> Perhaps you aren't aware that the capacitance of a CRT is
> >>>> measured
> >>>> in
> >>>> single-digit nanofarads, the capacitance of ultracapacitors is
> >>>> measured in hundreds of farads.
>
> >>> Perhaps you've never heard that 4,000,000 is a *BIG* number.
>
> >> So divide the capacitance of a d-cell ultracapacitor by the
> >> capacitance of a CRT and see what you get. =A0I think you'll find
> >> that
> >> it's a *BIGGER* number.
>
> > The energy stored in a "supercapactior" is *not* as much as stored
> > in the second anode circuit of a TV (it's a lot more than just the
> > glass).
>
> It's not? =A0Show me the numbers.
>
> --
> --
> --John
> to email, dial "usenet" and validate
> (was jclarke at eye bee em dot net)
http://i97.photobucket.com/albums/l240/robo848/not_this_shit_again.jpg
On Jul 2, 2:35=A0pm, "xcz" <[email protected]> wrote:
> http://www.onlinetoolreviews.com/reviews/gmcfastcellscrewdrivers.htm
>
> Enjoy.
>
> --
> --
> Regards,
>
> Dean Bielanowski
> Editor
> OnlineToolReviews.comhttp://www.onlinetoolreviews.com
> Over 190+ free tool reviews online!
so I can buy a GMC screwdriver for $100 (roughly 3.5 times the cost of
a B&D VersaPak) and trust that the capacitor will never go bad?
http://www.redboxhardware.com.au/index.aspx?page=3Dproducts&catid=3D2&scid=
=3D158&gid=3D2591
vs $29 B&D
http://www.amazon.com/Black-Decker-VP800-Black%2526-Screwdriver/dp/B001735RC=
U/ref=3Dpd_sim_hi_8
I'll skip both and stick with a screwdriver that has a 'real' lifetime
guarantee (including the battery)
http://buy1.snapon.com/catalog/item.asp?search=3Dtrue&item_ID=3D65&PartNo=3D=
SSDMR4B&group_id=3D702&supersede=3D&store=3Dsnapon-store&tool=3Dall
or
http://www.garrettwade.com/jump.jsp?itemType=3DPRODUCT&RS=3D1&itemID=3D11255=
3&keyword=3D08C03.01
Limp Arbor wrote:
> On Jul 2, 2:35 pm, "xcz" <[email protected]> wrote:
>> http://www.onlinetoolreviews.com/reviews/gmcfastcellscrewdrivers.htm
>>
>> Enjoy.
>>
>> --
>> --
>> Regards,
>>
>> Dean Bielanowski
>> Editor
>> OnlineToolReviews.comhttp://www.onlinetoolreviews.com
>> Over 190+ free tool reviews online!
>
> so I can buy a GMC screwdriver for $100 (roughly 3.5 times the cost
> of
> a B&D VersaPak) and trust that the capacitor will never go bad?
> http://www.redboxhardware.com.au/index.aspx?page=products&catid=2&scid=158&gid=2591
>
> vs $29 B&D
> http://www.amazon.com/Black-Decker-VP800-Black%2526-Screwdriver/dp/B001735RCU/ref=pd_sim_hi_8
>
> I'll skip both and stick with a screwdriver that has a 'real'
> lifetime
> guarantee (including the battery)
> http://buy1.snapon.com/catalog/item.asp?search=true&item_ID=65&PartNo=SSDMR4B&group_id=702&supersede=&store=snapon-store&tool=all
> or
> http://www.garrettwade.com/jump.jsp?itemType=PRODUCT&RS=1&itemID=112553&keyword=08C03.01
Do your "lifetime guarantee" tools charge in less than a minute?
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
Artemus wrote:
> I'm unimpressed.
>
> I went to the GMC website and found their so called specifications
> to
> be nothing more
> than an advertisement for the product.
Uh, what do you expect? The specifications for any product are an
advertisement for the product.
> Example: "High Shelf Life -
> Fully charged on
> it's own, the Flashcell will remain charged almost indefinitely".
> The phrase "almost
> indefinitely" is pure marketing speak. In your review you mentioned
> the relative
> self discharge rates for L-ion and NiCd but not a word about the
> GMC.
>
> Fast charging is great but how long does a charge last? How many
> screws will it
> drive?
>
> Chemical batteries have a shallow voltage discharge curve until the
> charge is almost
> depleted then it falls rapidly. A capacitors voltage immediately,
> and linearly,
> falls as charge is pulled out of it. At half charge there is half
> the initial
> voltage which will have a devastating effect on the torque produced
> by the driver.
> There is not a word about this on the GMC website. If the user has
> to recharge after
> only using 10% of the charge this would be a big negative.
What matters is how many fasteners it can drive on a charge, not what
percentage of discharge is achieved before it can no longer drive a
fastener with acceptable performance.
It's sold in the US under the "Coleman" brand and you can find another
review at
http://www.popularmechanics.com/blogs/technology_news/4223118.html.
According to them it can screw in 22 fasteners under the same
conditions that a Skil IXO can screw in 37.
The thing that fascinates me about this particular tool is that
capacitor technology has developed to the point that such a tool _can_
be made.
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
Hi,
I suspect that these super capacitors at least in tools are low
voltage, High current ( charge = number of extra electrons on one side
of the capacitor). Other than arcing they should not be dangerous.
Think of them like a car battery.
The capacitors in TV
s are high voltage.
Thanks
Roger
>
> I remember from electronics school, way back when the big cathode ray tube
> (TV's) was a field of study. And how we had to isolate them with special
> transformers and ground it before working. Otherwise, it would kill you.
> Because it was a massive capaciter that stored enough charge to zap your
> heart into the great beyond. And there were folks who killed themselves
> this way on a regular basis.
>
Lee Michaels wrote:
> "J. Clarke" <[email protected]> wrote
>>
>> The thing that fascinates me about this particular tool is that
>> capacitor technology has developed to the point that such a tool
>> _can_ be made.
>>
>>
> Same here.
>
> I remember from electronics school, way back when the big cathode
> ray
> tube (TV's) was a field of study. And how we had to isolate them
> with
> special transformers and ground it before working. Otherwise, it
> would kill you. Because it was a massive capaciter that stored
> enough
> charge to zap your heart into the great beyond. And there were
> folks
> who killed themselves this way on a regular basis.
>
> I think this technology is great though. I am just wondering when
> the
> charge gets big enough to become dangerous. And if it is enough
> power to do many of the jobs now done by portable tools using
> current
> battery technology. The nearly instant charge thing is really
> interesting. That feature is definitely different. It could easily
> change some work habits if it proves to work well.
>
> I have this image in my mind of a capaciter driven car. Can you
> imagine the charge that thing would take? And how many people would
> be electrocuted if the thing got into a wreck? One bright thought
> on
> that idea is that you could easily incorporate a deadly thief
> deterrent into its design.
A while back I picked up a 5 farad supercapacitor just to dink with.
The thing's about the diameter of a C cell and maybe a third the
height. Turns out that it's current delivery is limited due to a
fairly high internal resistance. That takes a lot of the danger out
of it. It's my understanding that when overvolted sufficiently they
die peacefully never to charge again--I never tried that with mine
though.
Remember, that CRT is charged to something in excess of 18KV--the high
voltage is what makes it dangerous. A supercapacitor can't handle
that kind of voltage.
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
Limp Arbor wrote:
> On Jul 2, 6:09 pm, "J. Clarke" <[email protected]> wrote:
>> Limp Arbor wrote:
>>> On Jul 2, 2:35 pm, "xcz" <[email protected]> wrote:
>>>> http://www.onlinetoolreviews.com/reviews/gmcfastcellscrewdrivers.htm
>>
>>>> Enjoy.
>>
>>>> --
>>>> --
>>>> Regards,
>>
>>>> Dean Bielanowski
>>>> Editor
>>>> OnlineToolReviews.comhttp://www.onlinetoolreviews.com
>>>> Over 190+ free tool reviews online!
>>
>>> so I can buy a GMC screwdriver for $100 (roughly 3.5 times the
>>> cost
>>> of
>>> a B&D VersaPak) and trust that the capacitor will never go bad?
>>> http://www.redboxhardware.com.au/index.aspx?page=products&catid=2&sci...
>>
>>> vs $29 B&D
>>> http://www.amazon.com/Black-Decker-VP800-Black%2526-Screwdriver/dp/B0...
>>
>>> I'll skip both and stick with a screwdriver that has a 'real'
>>> lifetime
>>> guarantee (including the battery)
>>> http://buy1.snapon.com/catalog/item.asp?search=true&item_ID=65&PartNo...
>>> or
>>> http://www.garrettwade.com/jump.jsp?itemType=PRODUCT&RS=1&itemID=1125...
>>
>> Do your "lifetime guarantee" tools charge in less than a minute?
>>
> No, takes about 8 hours but can go all day and then some.
Your 5.7v screwdriver goes "all day and then some"?
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
krw wrote:
> In article <[email protected]>, [email protected]
> says...
>> Lee Michaels wrote:
>>> "J. Clarke" <[email protected]> wrote
>>>>
>>>> The thing that fascinates me about this particular tool is that
>>>> capacitor technology has developed to the point that such a tool
>>>> _can_ be made.
>>>>
>>>>
>>> Same here.
>>>
>>> I remember from electronics school, way back when the big cathode
>>> ray
>>> tube (TV's) was a field of study. And how we had to isolate them
>>> with
>>> special transformers and ground it before working. Otherwise, it
>>> would kill you. Because it was a massive capaciter that stored
>>> enough
>>> charge to zap your heart into the great beyond. And there were
>>> folks
>>> who killed themselves this way on a regular basis.
>>>
>>> I think this technology is great though. I am just wondering when
>>> the
>>> charge gets big enough to become dangerous. And if it is enough
>>> power to do many of the jobs now done by portable tools using
>>> current
>>> battery technology. The nearly instant charge thing is really
>>> interesting. That feature is definitely different. It could
>>> easily
>>> change some work habits if it proves to work well.
>>>
>>> I have this image in my mind of a capaciter driven car. Can you
>>> imagine the charge that thing would take? And how many people
>>> would
>>> be electrocuted if the thing got into a wreck? One bright thought
>>> on
>>> that idea is that you could easily incorporate a deadly thief
>>> deterrent into its design.
>>
>> A while back I picked up a 5 farad supercapacitor just to dink
>> with.
>> The thing's about the diameter of a C cell and maybe a third the
>> height. Turns out that it's current delivery is limited due to a
>> fairly high internal resistance. That takes a lot of the danger
>> out
>> of it. It's my understanding that when overvolted sufficiently
>> they
>> die peacefully never to charge again--I never tried that with mine
>> though.
>>
>> Remember, that CRT is charged to something in excess of 18KV--the
>> high voltage is what makes it dangerous. A supercapacitor can't
>> handle that kind of voltage.
>
> The energy stored is what makes it dangerous. The 18kV makes the
> energy stored 4,000,000 times that of a 9V capacitor of the same
> capacitance.
So how many people died of electrocution from 2.7v sources in the past
100 years?
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
krw wrote:
> In article <[email protected]>, [email protected]
> says...
>> krw wrote:
>>> In article <[email protected]>, [email protected]
>>> says...
>>>> Lee Michaels wrote:
>>>>> "J. Clarke" <[email protected]> wrote
>>>>>>
>>>>>> The thing that fascinates me about this particular tool is that
>>>>>> capacitor technology has developed to the point that such a
>>>>>> tool
>>>>>> _can_ be made.
>>>>>>
>>>>>>
>>>>> Same here.
>>>>>
>>>>> I remember from electronics school, way back when the big
>>>>> cathode
>>>>> ray
>>>>> tube (TV's) was a field of study. And how we had to isolate them
>>>>> with
>>>>> special transformers and ground it before working. Otherwise, it
>>>>> would kill you. Because it was a massive capaciter that stored
>>>>> enough
>>>>> charge to zap your heart into the great beyond. And there were
>>>>> folks
>>>>> who killed themselves this way on a regular basis.
>>>>>
>>>>> I think this technology is great though. I am just wondering
>>>>> when
>>>>> the
>>>>> charge gets big enough to become dangerous. And if it is enough
>>>>> power to do many of the jobs now done by portable tools using
>>>>> current
>>>>> battery technology. The nearly instant charge thing is really
>>>>> interesting. That feature is definitely different. It could
>>>>> easily
>>>>> change some work habits if it proves to work well.
>>>>>
>>>>> I have this image in my mind of a capaciter driven car. Can you
>>>>> imagine the charge that thing would take? And how many people
>>>>> would
>>>>> be electrocuted if the thing got into a wreck? One bright
>>>>> thought
>>>>> on
>>>>> that idea is that you could easily incorporate a deadly thief
>>>>> deterrent into its design.
>>>>
>>>> A while back I picked up a 5 farad supercapacitor just to dink
>>>> with.
>>>> The thing's about the diameter of a C cell and maybe a third the
>>>> height. Turns out that it's current delivery is limited due to a
>>>> fairly high internal resistance. That takes a lot of the danger
>>>> out
>>>> of it. It's my understanding that when overvolted sufficiently
>>>> they
>>>> die peacefully never to charge again--I never tried that with
>>>> mine
>>>> though.
>>>>
>>>> Remember, that CRT is charged to something in excess of 18KV--the
>>>> high voltage is what makes it dangerous. A supercapacitor can't
>>>> handle that kind of voltage.
>>>
>>> The energy stored is what makes it dangerous. The 18kV makes the
>>> energy stored 4,000,000 times that of a 9V capacitor of the same
>>> capacitance.
>>
>> So how many people died of electrocution from 2.7v sources in the
>> past 100 years?
>
> How do you propose to store useful energy on a capacitor at 2.7V?
"Propose"? I don't need to "propose" anything, we're discussing a
commercial off the shelf product.
Perhaps you aren't aware that the capacitance of a CRT is measured in
single-digit nanofarads, the capacitance of ultracapacitors is
measured in hundreds of farads.
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
krw wrote:
> In article <[email protected]>, [email protected]
> says...
>> krw wrote:
>>> In article <[email protected]>, [email protected]
>>> says...
>>>> krw wrote:
>>>>> In article <[email protected]>,
>>>>> [email protected]
>>>>> says...
>>>>>> Lee Michaels wrote:
>>>>>>> "J. Clarke" <[email protected]> wrote
>>>>>>>>
>>>>>>>> The thing that fascinates me about this particular tool is
>>>>>>>> that
>>>>>>>> capacitor technology has developed to the point that such a
>>>>>>>> tool
>>>>>>>> _can_ be made.
>>>>>>>>
>>>>>>>>
>>>>>>> Same here.
>>>>>>>
>>>>>>> I remember from electronics school, way back when the big
>>>>>>> cathode
>>>>>>> ray
>>>>>>> tube (TV's) was a field of study. And how we had to isolate
>>>>>>> them
>>>>>>> with
>>>>>>> special transformers and ground it before working. Otherwise,
>>>>>>> it
>>>>>>> would kill you. Because it was a massive capaciter that stored
>>>>>>> enough
>>>>>>> charge to zap your heart into the great beyond. And there
>>>>>>> were
>>>>>>> folks
>>>>>>> who killed themselves this way on a regular basis.
>>>>>>>
>>>>>>> I think this technology is great though. I am just wondering
>>>>>>> when
>>>>>>> the
>>>>>>> charge gets big enough to become dangerous. And if it is
>>>>>>> enough
>>>>>>> power to do many of the jobs now done by portable tools using
>>>>>>> current
>>>>>>> battery technology. The nearly instant charge thing is really
>>>>>>> interesting. That feature is definitely different. It could
>>>>>>> easily
>>>>>>> change some work habits if it proves to work well.
>>>>>>>
>>>>>>> I have this image in my mind of a capaciter driven car. Can
>>>>>>> you
>>>>>>> imagine the charge that thing would take? And how many people
>>>>>>> would
>>>>>>> be electrocuted if the thing got into a wreck? One bright
>>>>>>> thought
>>>>>>> on
>>>>>>> that idea is that you could easily incorporate a deadly thief
>>>>>>> deterrent into its design.
>>>>>>
>>>>>> A while back I picked up a 5 farad supercapacitor just to dink
>>>>>> with.
>>>>>> The thing's about the diameter of a C cell and maybe a third
>>>>>> the
>>>>>> height. Turns out that it's current delivery is limited due to
>>>>>> a
>>>>>> fairly high internal resistance. That takes a lot of the
>>>>>> danger
>>>>>> out
>>>>>> of it. It's my understanding that when overvolted sufficiently
>>>>>> they
>>>>>> die peacefully never to charge again--I never tried that with
>>>>>> mine
>>>>>> though.
>>>>>>
>>>>>> Remember, that CRT is charged to something in excess of
>>>>>> 18KV--the
>>>>>> high voltage is what makes it dangerous. A supercapacitor
>>>>>> can't
>>>>>> handle that kind of voltage.
>>>>>
>>>>> The energy stored is what makes it dangerous. The 18kV makes
>>>>> the
>>>>> energy stored 4,000,000 times that of a 9V capacitor of the same
>>>>> capacitance.
>>>>
>>>> So how many people died of electrocution from 2.7v sources in the
>>>> past 100 years?
>>>
>>> How do you propose to store useful energy on a capacitor at 2.7V?
>>
>> "Propose"? I don't need to "propose" anything, we're discussing a
>> commercial off the shelf product.
>
> No, we're talking about someone's wet dream.
I'm sorry, but if it's in stock at Digi-Key it's not a "wet dream".
>> Perhaps you aren't aware that the capacitance of a CRT is measured
>> in
>> single-digit nanofarads, the capacitance of ultracapacitors is
>> measured in hundreds of farads.
>
>
> Perhaps you've never heard that 4,000,000 is a *BIG* number.
So divide the capacitance of a d-cell ultracapacitor by the
capacitance of a CRT and see what you get. I think you'll find that
it's a *BIGGER* number.
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
krw wrote:
> In article <[email protected]>, [email protected]
> says...
>> krw wrote:
>>> In article <[email protected]>, [email protected]
>>> says...
>>>> krw wrote:
>>>>> In article <[email protected]>,
>>>>> [email protected]
>>>>> says...
>>>>>> krw wrote:
>>>>>>> In article <[email protected]>,
>>>>>>> [email protected]
>>>>>>> says...
>>>>>>>> Lee Michaels wrote:
>>>>>>>>> "J. Clarke" <[email protected]> wrote
>>>>>>>>>>
>>>>>>>>>> The thing that fascinates me about this particular tool is
>>>>>>>>>> that
>>>>>>>>>> capacitor technology has developed to the point that such a
>>>>>>>>>> tool
>>>>>>>>>> _can_ be made.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>> Same here.
>>>>>>>>>
>>>>>>>>> I remember from electronics school, way back when the big
>>>>>>>>> cathode
>>>>>>>>> ray
>>>>>>>>> tube (TV's) was a field of study. And how we had to isolate
>>>>>>>>> them
>>>>>>>>> with
>>>>>>>>> special transformers and ground it before working.
>>>>>>>>> Otherwise,
>>>>>>>>> it
>>>>>>>>> would kill you. Because it was a massive capaciter that
>>>>>>>>> stored
>>>>>>>>> enough
>>>>>>>>> charge to zap your heart into the great beyond. And there
>>>>>>>>> were
>>>>>>>>> folks
>>>>>>>>> who killed themselves this way on a regular basis.
>>>>>>>>>
>>>>>>>>> I think this technology is great though. I am just
>>>>>>>>> wondering
>>>>>>>>> when
>>>>>>>>> the
>>>>>>>>> charge gets big enough to become dangerous. And if it is
>>>>>>>>> enough
>>>>>>>>> power to do many of the jobs now done by portable tools
>>>>>>>>> using
>>>>>>>>> current
>>>>>>>>> battery technology. The nearly instant charge thing is
>>>>>>>>> really
>>>>>>>>> interesting. That feature is definitely different. It
>>>>>>>>> could
>>>>>>>>> easily
>>>>>>>>> change some work habits if it proves to work well.
>>>>>>>>>
>>>>>>>>> I have this image in my mind of a capaciter driven car. Can
>>>>>>>>> you
>>>>>>>>> imagine the charge that thing would take? And how many
>>>>>>>>> people
>>>>>>>>> would
>>>>>>>>> be electrocuted if the thing got into a wreck? One bright
>>>>>>>>> thought
>>>>>>>>> on
>>>>>>>>> that idea is that you could easily incorporate a deadly
>>>>>>>>> thief
>>>>>>>>> deterrent into its design.
>>>>>>>>
>>>>>>>> A while back I picked up a 5 farad supercapacitor just to
>>>>>>>> dink
>>>>>>>> with.
>>>>>>>> The thing's about the diameter of a C cell and maybe a third
>>>>>>>> the
>>>>>>>> height. Turns out that it's current delivery is limited due
>>>>>>>> to
>>>>>>>> a
>>>>>>>> fairly high internal resistance. That takes a lot of the
>>>>>>>> danger
>>>>>>>> out
>>>>>>>> of it. It's my understanding that when overvolted
>>>>>>>> sufficiently
>>>>>>>> they
>>>>>>>> die peacefully never to charge again--I never tried that with
>>>>>>>> mine
>>>>>>>> though.
>>>>>>>>
>>>>>>>> Remember, that CRT is charged to something in excess of
>>>>>>>> 18KV--the
>>>>>>>> high voltage is what makes it dangerous. A supercapacitor
>>>>>>>> can't
>>>>>>>> handle that kind of voltage.
>>>>>>>
>>>>>>> The energy stored is what makes it dangerous. The 18kV makes
>>>>>>> the
>>>>>>> energy stored 4,000,000 times that of a 9V capacitor of the
>>>>>>> same
>>>>>>> capacitance.
>>>>>>
>>>>>> So how many people died of electrocution from 2.7v sources in
>>>>>> the
>>>>>> past 100 years?
>>>>>
>>>>> How do you propose to store useful energy on a capacitor at
>>>>> 2.7V?
>>>>
>>>> "Propose"? I don't need to "propose" anything, we're discussing
>>>> a
>>>> commercial off the shelf product.
>>>
>>> No, we're talking about someone's wet dream.
>>
>> I'm sorry, but if it's in stock at Digi-Key it's not a "wet dream".
>
> The existence of a "supercapacitor" isn't the issue.
>
>>>> Perhaps you aren't aware that the capacitance of a CRT is
>>>> measured
>>>> in
>>>> single-digit nanofarads, the capacitance of ultracapacitors is
>>>> measured in hundreds of farads.
>>>
>>>
>>> Perhaps you've never heard that 4,000,000 is a *BIG* number.
>>
>> So divide the capacitance of a d-cell ultracapacitor by the
>> capacitance of a CRT and see what you get. I think you'll find
>> that
>> it's a *BIGGER* number.
>
> The energy stored in a "supercapactior" is *not* as much as stored
> in the second anode circuit of a TV (it's a lot more than just the
> glass).
It's not? Show me the numbers.
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
In article <[email protected]>,
Lee Michaels <[email protected]> wrote:
>
>"Larry W" wrote
>>
>> "And there were folks who killed themselves this way on a regular basis."
>>
>>
>> I just LOVE that line!
>>
>>
>Well........, when you are working with high voltage and/or current, you
>have to be careful. And the message was pounded home by instructors, many
>of them ex-military, who had some gory stories to tell.
>
>We had an expression in that school. If somebody got a shock, we said they
>got "bit". And often when this "biting" took place, there was some yelling
<...snipped...>
Uhh, What I found humorous was that while it is conceivable that someone
would get "bit" on a regular basis, "killed" is generally a one-time
kind of experience.
--
Often wrong, never in doubt.
Larry Wasserman - Baltimore Maryland - lwasserm(a)sdf. lonestar. org
"Artemus" <[email protected]> wrote in message
news:[email protected]...
> I'm unimpressed.
>
> I went to the GMC website and found their so called specifications to be
> nothing more
> than an advertisement for the product. Example: "High Shelf Life - Fully
> charged on
> it's own, the Flashcell will remain charged almost indefinitely". The
> phrase "almost
> indefinitely" is pure marketing speak. In your review you mentioned the
> relative
> self discharge rates for L-ion and NiCd but not a word about the GMC.
>
> Fast charging is great but how long does a charge last? How many screws
> will it
> drive?
>
> Chemical batteries have a shallow voltage discharge curve until the charge
> is almost
> depleted then it falls rapidly. A capacitors voltage immediately, and
> linearly,
> falls as charge is pulled out of it. At half charge there is half the
> initial
> voltage which will have a devastating effect on the torque produced by the
> driver.
> There is not a word about this on the GMC website. If the user has to
> recharge after
> only using 10% of the charge this would be a big negative.
>
> Art
IIRC he mentioned that the battery probably has 60-70 of the capacity of a
modern style rechargeable tool battery. It could be 25% and with a 90
second recharge that would be OK with me.
"J. Clarke" <[email protected]> wrote
>
> The thing that fascinates me about this particular tool is that
> capacitor technology has developed to the point that such a tool _can_
> be made.
>
>
Same here.
I remember from electronics school, way back when the big cathode ray tube
(TV's) was a field of study. And how we had to isolate them with special
transformers and ground it before working. Otherwise, it would kill you.
Because it was a massive capaciter that stored enough charge to zap your
heart into the great beyond. And there were folks who killed themselves
this way on a regular basis.
I think this technology is great though. I am just wondering when the
charge gets big enough to become dangerous. And if it is enough power to do
many of the jobs now done by portable tools using current battery
technology. The nearly instant charge thing is really interesting. That
feature is definitely different. It could easily change some work habits if
it proves to work well.
I have this image in my mind of a capaciter driven car. Can you imagine the
charge that thing would take? And how many people would be electrocuted if
the thing got into a wreck? One bright thought on that idea is that you
could easily incorporate a deadly thief deterrent into its design.
"Larry W" <[email protected]> wrote in message
news:[email protected]...
> In article <[email protected]>,
> Lee Michaels <[email protected]> wrote:
>>
>>"Larry W" wrote
>>>
>>> "And there were folks who killed themselves this way on a regular
>>> basis."
>>>
>>>
>>> I just LOVE that line!
>>>
>>>
>>Well........, when you are working with high voltage and/or current, you
>>have to be careful. And the message was pounded home by instructors, many
>>of them ex-military, who had some gory stories to tell.
>>
>>We had an expression in that school. If somebody got a shock, we said they
>>got "bit". And often when this "biting" took place, there was some
>>yelling
> <...snipped...>
>
>
>
> Uhh, What I found humorous was that while it is conceivable that someone
> would get "bit" on a regular basis, "killed" is generally a one-time
> kind of experience.
>
>
OK, gotcha. I was making a general, big picture kinda statement. You read
it as a personal, singular kinda thing. As in killing themselves over and
over again.