there was a cordless 18v drill that got a good write up in Which so I went out and bought one - now I wonder if I did the right thing because it has a NI-CAD Battery ( not bad at 1.5 amp hours tho)

I know about the memory thing and have had drills in the past that have not lasted long (small batteries) but I was wondering how the modern NI-CADs compare with the old type

Can anyone give me any advice/their experiences? shall I take it back and buy a more expensive one or will it do for general use?

The problem is that it will be only be used for DIY stuff and so wont be fully discharged ( and may be stored away 1/2 charged etc as it is used intermittantly)

It says in the manual that before first us it should be charged and discharged 5 times - sounds like a pratt on????

what do you think!!! - any comment appreciated

pete

"peterx666" wrote in message
news

there was a cordless 18v drill that got a good write up in Which so I
went out and bought one - now I wonder if I did the right thing because
it has a NI-CAD Battery ( not bad at 1.5 amp hours tho)

I know about the memory thing and have had drills in the past that have
not lasted long (small batteries) but I was wondering how the modern
NI-CADs compare with the old type

Can anyone give me any advice/their experiences? shall I take it back
and buy a more expensive one or will it do for general use?

The problem is that it will be only be used for DIY stuff and so wont
be fully discharged ( and may be stored away 1/2 charged etc as it is
used intermittantly)

It says in the manual that before first us it should be charged and
discharged 5 times - sounds like a pratt on????

what do you think!!! - any comment appreciated

pete




--
peterx666

I remember reading an interesting article some years ago.
Google 'NICAD memory effect' and bingo!

http://www.repairfaq.org/ELE/F_NiCd_Battery.html

Phil

In article ,
peterx666 wrote:
there was a cordless 18v drill that got a good write up in Which so I
went out and bought one - now I wonder if I did the right thing because
it has a NI-CAD Battery ( not bad at 1.5 amp hours tho)

I know about the memory thing

No such thing in practice.

and have had drills in the past that have
not lasted long (small batteries) but I was wondering how the modern
NI-CADs compare with the old type

Ni-Cads are like cars. They come in all shapes sizes and quality.
Generally, the ones supplied with cheap tools are cheap and nasty. Those
with more expensive ones better.

Can anyone give me any advice/their experiences? shall I take it back
and buy a more expensive one or will it do for general use?

Did Which test the battery for number of charge/discharge cycles? That's
what differentiates a decent one from a poor one.

The problem is that it will be only be used for DIY stuff and so wont
be fully discharged ( and may be stored away 1/2 charged etc as it is
used intermittantly)

Doesn't matter. But *don't* discharge it fully. Recharge when the
performance dictates this - don't be tempted to leave the drill running
until it stops.

It says in the manual that before first us it should be charged and
discharged 5 times - sounds like a pratt on????

Sounds rubbish to me.

what do you think!!! - any comment appreciated

The other thing is the type and quality of the charger. That makes a vast
difference to life as overcharging is about the worst thing you can do.

--
*A cubicle is just a padded cell without a door.

Dave Plowman London SW
To e-mail, change noise into sound.

On 17 Apr, 19:02, peterx666 wrote:

there was a cordless 18v drill that got a good write up in Which so I
went out and bought one - now I wonder if I did the right thing because
it has a NI-CAD Battery ( not bad at 1.5 amp hours tho)

it wouldnt work very well if it didnt have one. Almost all codless
tools use nicads.


I know about the memory thing and have had drills in the past that have
not lasted long (small batteries) but I was wondering how the modern
NI-CADs compare with the old type

same thing

Can anyone give me any advice/their experiences? shall I take it back
and buy a more expensive one or will it do for general use?

these questions have nothing to do with it using nicads.

The problem is that it will be only be used for DIY stuff and so wont
be fully discharged ( and may be stored away 1/2 charged etc as it is
used intermittantly)

not a problem, normal use.


It says in the manual that before first us it should be charged and
discharged 5 times - sounds like a pratt on????

I dont know what you mean but the 5 cycle advice is worthless.


NT

Dave Plowman (News) wrote:

I know about the memory thing

No such thing in practice.

Ni-Cads are like cars. They come in all shapes sizes and quality.
Generally, the ones supplied with cheap tools are cheap and nasty.
Those with more expensive ones better.

Could you elaborate on that please Dave? I recently bought a 'bargain'
Bosch 9.6v driver and the charger seems very basic. Bosch tech services
confirm that the charger only has a 'power' light & doesn't switch off when
the battery is fully charged, and that the re charge time is 3-5 hours which
has to be timed manually.

Doesn't matter. But *don't* discharge it fully. Recharge when the
performance dictates this - don't be tempted to leave the drill
running until it stops.

I've looked at buying a spare battery, but that exceeds the cost of the
driver and isn't viable. I love the little Bosch machine for suitable jobs,
but I'm completely confused about the charging thing.


--
Dave
The Medway Handyman
www.medwayhandyman.co.uk
01634 717930
07850 597257

In article ,
The Medway Handyman wrote:
Ni-Cads are like cars. They come in all shapes sizes and quality.
Generally, the ones supplied with cheap tools are cheap and nasty.
Those with more expensive ones better.

Could you elaborate on that please Dave? I recently bought a 'bargain'
Bosch 9.6v driver and the charger seems very basic. Bosch tech services
confirm that the charger only has a 'power' light & doesn't switch off
when the battery is fully charged, and that the re charge time is 3-5
hours which has to be timed manually.

Then make sure you only re-charge when the performance dictates this and
observe the time religiously. If you want the best life from the
batteries. Personally I prefer the old standard 1/10th capacity charge
rate for 14 hours. Which is a convenient time between finishing work one
day and starting the next. My charging bench has a one shot timer which
does just this.

Doesn't matter. But *don't* discharge it fully. Recharge when the
performance dictates this - don't be tempted to leave the drill
running until it stops.

I've looked at buying a spare battery, but that exceeds the cost of the
driver and isn't viable. I love the little Bosch machine for suitable
jobs, but I'm completely confused about the charging thing.

You could buy an intelligent charger - there are types available which do
a wide range of voltages and capacities without needing heat sensors, etc.
Mascot are my favourite. But unfortunately not cheap.

--
*Change is inevitable, except from a vending machine*

Dave Plowman London SW
To e-mail, change noise into sound.

In message , peterx666
writes
I know about the memory thing and have had drills in the past that
have
not lasted long (small batteries) but I was wondering how the
modern
NI-CADs compare with the old type

Modern NiCd's are very good. The memory effect isn't such an issue
these days. Obviously they don't hold as much of a charge as NiMh
cells, but they are a lot cheaper and time proven.

It says in the manual that before first us it should be charged
and
discharged 5 times - sounds like a pratt on????

A new battery doesn't reach it's full capacity until it's been through a
few charge / discharge cycles. Just normal use is fine.

The thing that damages batteries the most is over discharge. When you
try to get "just one more hole" from a flat drill battery it drives the
discharged cells in reverse and reduces their capacity.

--
Clive Mitchell
http://www.bigclive.com

In message , The Medway Handyman
writes
Could you elaborate on that please Dave? I recently bought a 'bargain'
Bosch 9.6v driver and the charger seems very basic. Bosch tech
services confirm that the charger only has a 'power' light & doesn't
switch off when the battery is fully charged, and that the re charge
time is 3-5 hours which has to be timed manually.

Those are the worst type of charger since it's easy to forget the
battery is on charge and the charge current is above the level where it
can be left on charge indefinitely.

Even the most basic chargers like the Ryobi one hour type use a thermal
switch in the pack to detect the end of charge when the batteries
suddenly start getting warm. Proper charge detection uses negative
delta V which monitors for a sudden voltage fall at the end of charge
due to bubbles on the electrode surface.

A perfect battery that actually used a pressure switch internally to
detect the pressure build up at the end of charge was developed by
Uniross (I think). You simply couldn't overcharge those cells, but they
were expensive and weren't promoted properly.

I've looked at buying a spare battery, but that exceeds the cost of the
driver and isn't viable. I love the little Bosch machine for suitable
jobs, but I'm completely confused about the charging thing.

If you can handle a super long recharge time you could hack the charger
by adding a higher value of series resistor to lower the current to
something suitable for unattended charging.

--
Clive Mitchell
http://www.bigclive.com

The Medway Handyman wrote:

Ni-Cads are like cars. They come in all shapes sizes and quality.
Generally, the ones supplied with cheap tools are cheap and nasty.
Those with more expensive ones better.

Could you elaborate on that please Dave?

There are several factors at play here. There is basic cell quality -
some are just better made than others. The better ones will have lower
internal resistances, and be able to supply higher peak currents. Better
quality ones will also tend to perform more consistently across
different examples of the same type of cell (see matching below).

Capacity varies greatly. Most batteries are assembled from SUB C sized
cells. The lower capacity ones start at 1.3Ah, better ones hold mare.

Next you have matching - higher quality packs will have better matched
cells (i.e. cells that exhibit similar discharge characteristics to
their neighbours). This means that all the cells run out of puff at
about the same time. This gives a nice sharp drop off in performance
(rather than a lingering decay), and minimises the chance that the
weaker cells will get reverse biased by the stronger ones should someone
try to wring the last few drops of capacity out of the pack (this will
kill cells PDQ!) If you want the highest quality packs then you need to
use graded or matched cells (not usually found in power tools, but the
performance electric modellers will go in for this sort of stuff).


I recently bought a 'bargain'
Bosch 9.6v driver and the charger seems very basic. Bosch tech services
confirm that the charger only has a 'power' light & doesn't switch off when
the battery is fully charged, and that the re charge time is 3-5 hours which
has to be timed manually.

The worst of both worlds in a way - enough charge current to cook the
cells, and no mechanism for stopping automatically.

Treating it to a decent delta peak charger would improve it greatly. You
can probably buy one of the ones designed for the blue Bosch tools,
assuming the connector layout is the same or could be adapted, but it
will probably cost more than the whole drill!

http://www.lawson-his.co.uk/scripts/...sch%20Chargers

There are plenty of circuits about (and ICs that do all the cleaver
stuff for you) so you can knock one up in you felt that way inclined.

I've looked at buying a spare battery, but that exceeds the cost of the
driver and isn't viable.

Buy another drill then - cheap way to get a battery. Makro were knocking
out 9.6V green Bosch drill drivers at £20 last time I looked.

I love the little Bosch machine for suitable jobs,
but I'm completely confused about the charging thing.

Its built down to a price, on a relatively safe assumption that most
causal owners will probably never get through more than a dozen charge
cycles in a year. So even if the charger knackers the cells after only
fifty cycles it will still feel like they lasted a good while.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Wed, 18 Apr 2007 00:23:00 GMT, Clive Mitchell wrote:

The thing that damages batteries the most is over discharge. When you
try to get "just one more hole" from a flat drill battery it drives the
discharged cells in reverse and reduces their capacity.

Followed by a cheap charger that doesn't have any built in charge
detection or time switch and uses charge current way above that which can
be left connected indefinately.

A "one shot timer" is a very useful bit of kit for charging kit. I've made
one from mechanical time switch. Simply move the motor feed to after the
switch. Turn the dial to start it, set how long you want it to run and it
does until the off point where upon it switches itself off.

--
Cheers
Dave. pam is missing e-mail

Thanks for all your help

From what I see the new NI-CADs are much better provided I do not run the drill down to nothing (which I did with my old drill by wrapping the switch with string to zero it - and the batteries didnt last) and I just charge for the 1 hour it says

Possibly a timer would be a good idea - have one in the kitchen I think!

So the overall impression is that I should keep the drill and not take it back?

pete

I recently bought a 'bargain'
Bosch 9.6v driver and the charger seems very basic. Bosch tech services
confirm that the charger only has a 'power' light & doesn't switch off when
the battery is fully charged, and that the re charge time is 3-5 hours which
has to be timed manually.


Treating it to a decent delta peak charger would improve it greatly. You
can probably buy one of the ones designed for the blue Bosch tools,
assuming the connector layout is the same or could be adapted, but it
will probably cost more than the whole drill!

I bought into the Bosch 14.4V blue series and cells/chargers/tools
seem fully interchangeable with the green series. Also the higher
voltage chargers always support automatic charging of the lower
voltage stuff as well.

The 9.6V Bosch series is probably near end of life - which is both
good and bad - not worth expanding your collection of stuff - but
bargains available on ebay (beware of lookalike batteries on ebay,
that may be of questionable quality)

wrote:

I bought into the Bosch 14.4V blue series and cells/chargers/tools
seem fully interchangeable with the green series. Also the higher

That is handy to know...

voltage chargers always support automatic charging of the lower
voltage stuff as well.

That seems to be a common pattern for the "pro" chargers (probably
because the are proper constant current chargers and the voltage is
controlled automatically in response to cell condition). My Makita 18V
charger will happily do anything from 7.2V to 18V, NiCd or NiMH.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

peterx666 wrote:

From what I see the new NI-CADs are much better provided I do not run
the drill down to nothing (which I did with my old drill by wrapping
the switch with string to zero it - and the batteries didnt last) and

Just run it until it shows signs of getting close to empty - don't try
to flatten the battery, or else you will kill it. If you have been using
it hard and the battery feel warm, then let it cool off before charging it.

I just charge for the 1 hour it says

If it is a one hour charger - the yes

(chargers this fast normally have some form of automatic cut off, if it
does then good. If not then be *very* careful not to overcharge as doing
so with a fast charger will also nuke a battery quickly)

Possibly a timer would be a good idea - have one in the kitchen I
think!

So the overall impression is that I should keep the drill and not take
it back?

If it feels comfortable for you, and performs well enough (enough
torque, run time, and the speed controller is ok), then keep it.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

In article om,
Dave Liquorice wrote:
A "one shot timer" is a very useful bit of kit for charging kit. I've
made one from mechanical time switch. Simply move the motor feed to
after the switch. Turn the dial to start it, set how long you want it
to run and it does until the off point where upon it switches itself
off.

I used the very handy U6046/7 series of chips by Temic - originally
designed for car heated rear window use and sadly no longer easily
available. It's similar to a low power 555, but has a variety of input
trigger facilities and the ability to drive a relay coil up to 300mA. Time
can be from 3.7s to 20h by the selection of two components.

--
*Prepositions are not words to end sentences with *

Dave Plowman London SW
To e-mail, change noise into sound.

In message , peterx666
writes
provided I do not run
the drill down to nothing (which I did with my
old drill by wrapping
the switch with string to zero it - and the
batteries didnt last)

NO. NO. NO. NO. NOOOOOOOOO!

I don't know where this urban legend crept in, but it's a sure fire way
to destroy batteries.

--
Clive Mitchell
http://www.bigclive.com

peterx666 wrote:

there was a cordless 18v drill that got a good write up in Which so I
went out and bought one - now I wonder if I did the right thing because
it has a NI-CAD Battery ( not bad at 1.5 amp hours tho)

I know about the memory thing and have had drills in the past that have
not lasted long (small batteries) but I was wondering how the modern
NI-CADs compare with the old type

What "memory thing"? It doesn't exist for domestic use of NiCd
batteries.

--
Chris Green

Clive Mitchell wrote

In message , peterx666
writes
provided I do not run the drill down to nothing (which I did with my
old drill by wrapping the switch with string to zero it - and the
batteries didnt last)

NO. NO. NO. NO. NOOOOOOOOO!

I don't know where this urban legend crept in, but it's a sure fire way
to destroy batteries.

Well, the phrase 'deep discharge' springs to mind. It's a catchy
enough phrase to imply to the less-knowledgeable[1] that it must be a
Good Thing(tm) and something that everyone should have a go at.

Footnote
--------
1. What's that saying about a little knowledge...? g

--
-blj-

In article ,
Brian L Johnson wrote:
Clive Mitchell wrote

In message , peterx666
writes
provided I do not run the drill down to nothing (which I did with my
old drill by wrapping the switch with string to zero it - and the
batteries didnt last)

NO. NO. NO. NO. NOOOOOOOOO!

I don't know where this urban legend crept in, but it's a sure fire way
to destroy batteries.

Well, the phrase 'deep discharge' springs to mind. It's a catchy
enough phrase to imply to the less-knowledgeable[1] that it must be a
Good Thing(tm) and something that everyone should have a go at.

Footnote
--------
1. What's that saying about a little knowledge...? g

'Deep discharge' is usually applied to lead acid types and is also a 'bad
thing'. ;-)

--
*Virtual reality is its own reward*

Dave Plowman London SW
To e-mail, change noise into sound.

In message , Brian L
Johnson writes
Well, the phrase 'deep discharge' springs to mind. It's a catchy
enough phrase to imply to the less-knowledgeable[1] that it must be a
Good Thing(tm) and something that everyone should have a go at.

It sounds like a sexual experience.

--
Clive Mitchell
http://www.bigclive.com

Clive Mitchell wrote

Well, the phrase 'deep discharge' springs to mind.
snip

It sounds like a sexual experience.

See? I *knew* that it sounded vaguely sexy!

--
-blj-

Brian L Johnson wrote in
:


Footnote
--------
1. What's that saying about a little knowledge...? g

"A little _learning_ is a dangerous thing;
Drink deep, or taste not the Pierian spring:" Al Pope

BOF

mike wrote

Brian L Johnson wrote in
:

1. What's that saying about a little knowledge...? g

"A little _learning_ is a dangerous thing;
Drink deep, or taste not the Pierian spring:" Al Pope

I rest my case.

--
-blj-