Date:

Author: Bernard Cleyet

Subject: Re: Driven Harmonic Motion Analyzer, PASCO, Brushes

Post:


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My experience w/ Caig (Laboratories, Inc.) has been very good, but =20
except in one case has been only w/ cable contacts. That exception, =20
IIRC, was w/ a sliding contact -- maybe??? generator commutator in my =20=

bug?? I used another of their products a paste containing quartz =20
particles in addition to their proprietary anti-oxidant and =20
preservative solvent.

Cramolin Paste type Qc

bc thinks good pics. (Show contacts well.) But ...

p.s. The solvent washes the carbon debris in to the spaces between =20
the commutator contact and shorts them. That's why I asked about the =20=

geometry. Now I've seen it, my (the web page to which I thought I =20
had referred) warning is inapplicable. Chalk is a mild (very) =20
abrasive. Before going much further (purchase of the paste, etc.) =20
I'd try cleaning the contacts well bending the leaf springs for more =20
pressure and applying (liberally) a lithium * grease. BTW? Are the =20
carbon brushes inside what appears to be rectangular copper cases, or =20=

are they the carbon brushes? The carbon is barely proud if so. Does =20=

the contact force come from the phosphor bronze leaf springs or a =20
coil spring in the cases. All this is not obvious from the pics.

*I have a tube of lithium grease just for its anti-humid properties.

Finally my experience w/ the east coast is it has a very unpleasant =20
ambience. Do you find the failures much more often during the Summer =20=

or the same as when there's snow?



On 2009, Mar 20, , at 13:31, Bill Norwood wrote:

> Hi Taplers,
>
> Re: trouble-shooting the contact brushes in our PASCO Driven =20
> Harmonic Motion Analyzer ME-9210A
>
> The geometry is attached (photos)
> (Only the copy that is going to Bernard has the attachments. Will =20
> provide you a copy on request)
>
> I have read most of the link Bernard Cleyet provided about =20
> maintaining motor brushes,
> http://www.uiitraining.com/b51a/300/3201and36021.htm
> and see that silicon from a variety of sources can form an =20
> insulating film
>
> But I learn from: http://www.hifigear.co.uk/site/scripts/=20
> product_browse.php?category_id=3D&product_id=3D3862
> that the DeoxIT we sometimes use on these contacts removes silicon.
> Description they provide: Caig produce two products ideal for audio =20=

> and AV use, these are DeoxIT and ProGold. DeoxIT is a contact =20
> cleaner featuring a fast-acting deoxidizing solution that cleans, =20
> preserves and lubricates as well as improving the conductivity on =20
> all metal connectors and contacts. DeoxIT is recommended for =20
> surfaces that have oxidation or corrosion. Even brand new audio or =20
> AV products benefit from their contacts being cleaned, as the =20
> connectors are often machined using silicon oil which is left to =20
> dry on after the manufacturing process.
> BN? But why do the DeoxIT-soaked contacts still fail after a few =20
> hours of use or after a few months of sitting?
>
> But Erich Burton says,
> Not sure about cleaning the brushes; I haven't had to do that in a =20
> while. I did have to replace a couple of the LEDs a while back, but =20=

> I haven't opened one of those units up lately.
> BN? Why doesn=E2=80=99t he have to clean his contacts regularly??
>
> And Jerry Hester smells something amiss,
> Hmmm,
> It seems that all kinds of electric motors use carbon brushes and =20
> run for years with no problems.
> What is different in your setup?
> BNR: Certainly much lower speeds, and the usage of steel and brass =20
> as the rotating surfaces, and, perhaps it matters that they are =20
> used in only one lab which runs these machines for just a week 3 =20
> times a year.
>
> And Bernard Cleyet writes,
> Do not use solvents!...
> I used chalk on a=EF=BF=BDmotor-generator=EF=BF=BDpowering a Beta-ray =20=

> spectrometer (cylindrical type).
> BN?: What=E2=80=99s wrong with solvents? DeoxIT is a solvent? How =
does =20
> chalk work?
>
> And LeRoy Frahm writes,
> Bill,
> On all my rotating or moving electrical contacts, I use a =20
> product that is a conducting
> lubricant and cleaner to restore good contact and reduce arcing. =20
> What I use is Rawn
> Aero 2000, Cleaner Lube. I get it from a local electronics =20
> supplier, I'm sure there are
> other brands, but this works great and made in a small local town =20
> (Spooner) in Wisconsin.
> There number is 1-800-826-6791.
> All the Best,
> LeRoy
> BN? Why would this be any different from the DeoxIT in our =20
> application?
>
>
> Many thanks for your brainstorming on this.
>
> Bill Norwood
> U of MD at College Park
>
>
> From: tap-l-owner@lists.ncsu.edu [mailto:tap-l-=20
> owner@lists.ncsu.edu] On Behalf Of Bernard Cleyet
> Sent: Thursday, March 19, 2009 4:23 PM
> To: tap-l@lists.ncsu.edu
> Subject: Re: [tap-l] Driven Harmonic Motion Analyzer, PASCO, Brushes
>
> I discover I didn't attache the link.
>
> http://www.uiitraining.com/b51a/300/3201and36021.htm
>
> bc
>
>
> On 2009, Mar 19, , at 11:09, Bernard Cleyet wrote:
>
> Do not use solvents! (I don't know the geometry.)
>
> http://www.morganamt.com/pdf/TB11_DustRemoval.pdf
>
> I used chalk on a motor-generator powering a Beta-ray spectrometer =20
> (cylindrical type).
>
> Here's a rather detailed servicing of a motor generator. You may be =20=

> having a problem w/ eccentricity. Note the instruction for =20
> resurfacing. [Go to cleaning slip rings.]
>
> Note: improper pressure, if the brush is worn the pressure may be =20
> too low. I suspect proper pressure results in self cleaning. Is the =20=

> ambience high humidity?
>
> bc read just enuf to think should send
>
>
>
>
> On 2009, Mar 19, , at 08:10, Bill Norwood wrote:
>
> Hi Taplers,
> Back again with the PASCO ME-9210A Driven FHM Analyzer:
> Due to dimming and eventual non-lighting of the rotating LED,
> We must frequently clean the sliding contacts,
> which uses up too much time and disrupts the labs.
> One contact is carbon-to-steel (brush against rotating shaft)
> Other contact is carbon-to-brass (brush against rotating annular ring)
> cut


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charset=UTF-8

My experience w/ Caig =
(Laboratories, Inc.) has been very good, but except in one case has been =
only w/ cable contacts. =C2=A0That exception, IIRC, was w/ a sliding =
contact -- maybe??? generator commutator in my bug?? =C2=A0 I used =
another of their=C2=A0products=C2=A0a paste containing quartz particles =
in addition to their=C2=A0proprietary=C2=A0anti-oxidant =
and=C2=A0preservative=C2=A0solvent. =C2=A0

Cramolin = =C2=A0Paste =C2=A0type Qc

bc =C2=A0thinks good = pics. =C2=A0(Show=C2=A0contacts=C2=A0well.)
=C2=A0But = ...

p.s. =C2=A0The solvent washes the carbon = debris in to the spaces
between the commutator contact and shorts them. =
=C2=A0That's=C2=A0why I asked about the geometry. =C2=A0Now I've
seen = it, my (the web page to which I thought I had referred)
warning is = inapplicable. =C2=A0Chalk is a mild (very) abrasive.
=C2=A0Before going = much further (purchase=C2=A0of the paste, etc.)
I'd try cleaning = the=C2=A0contacts=C2=A0well bending the leaf
springs for more pressure = and applying (liberally) a lithium *
grease. =C2=A0BTW? =C2=A0Are the = carbon brushes inside what
appears to be rectangular copper cases, or = are they the
carbon=C2=A0brushes? =C2=A0The carbon is barely proud if = so.
=C2=A0Does the contact force come from =
the=C2=A0phosphor=C2=A0bronze=C2=A0leaf=C2=A0springs or a coil
spring in = the cases. =C2=A0All this is not obvious from the = pics.

*I have a tube of lithium grease just for = its anti-humid properties.

Finally my = experience w/ the east coast is it has a very
unpleasant ambience. =C2=A0D= o you find the failures much more
often during the Summer or the same as = when there's = snow?



On 2009, Mar = 20, , at 13:31, Bill Norwood wrote:

Hi Taplers,
Re: trouble-shooting the contact brushes in our =
PASCO=C2=A0Driven Harmonic Motion = Analyzer ME-9210A
The geometry is attached = (photos)
(Only the copy that is going to Bernard has the = attachments.
Will provide you a copy on = request)
=C2=A0
I have = read most of the link Bernard Cleyet provided about
maintaining motor = brushes,
and see that silicon from a variety of sources can form = an
insulating film
But I learn from:=C2=A0=C2=A0that the = DeoxIT we sometimes use
on these contacts removes = silicon.
Description they provide: Caig produce two products = ideal for
audio and AV use, these are DeoxIT and ProGold. DeoxIT is a =
contact cleaner featuring a fast-acting deoxidizing solution
that = cleans, preserves and lubricates as well as improving the
conductivity = on all metal connectors and contacts. DeoxIT is
recommended for surfaces = that have oxidation or corrosion.
Even brand new audio or AV products = benefit from their
contacts being cleaned, as the connectors are often = machined
using silicon oil which is left to dry on after the =
manufacturing process.
BN?=C2=A0 = But why do the DeoxIT-soaked contacts still fail
after a few hours of = use or after a few months of sitting?
But Erich Burton = says,
Not sure about cleaning the brushes; I haven't had to do = that
in a while. I did have to replace a couple of the LEDs a while =
back, but I haven't opened one of those units up = lately.
BN?=C2=A0 Why doesn=E2=80=99t he have to clean his = contacts
regularly??
And Jerry Hester smells something = amiss,
Hmmm,
It seems that all kinds of electric motors use = carbon brushes
and run for years with no problems.
What is different = in your setup?
BNR: Certainly much lower speeds, = and the usage of steel and
brass as the rotating surfaces, and, perhaps = it matters that
they are used in only one lab which runs these machines = for
just a week 3 times a year.
And Bernard Cleyet = writes,
Do not use = solvents!...
I used chalk on amotor-generatorpowering a Beta-ray spectrometer
(cylindrical = type).
BN?:=C2=A0 What=E2=80=99s wrong with solvents? DeoxIT is = a
solvent? How does chalk work?
And LeRoy Frahm = writes,
Bill,
=C2=A0=C2=A0= =C2=A0 On all my rotating or moving electrical
contacts, I use a = product that is a conducting
lubricant = and cleaner to restore good contact and reduce
arcing. What I use is = Rawn
Aero 2000, Cleaner Lube. I get it from a local = electronics
supplier, I'm sure there = are
other brands, but this works great and made in a small = local
town (Spooner) in=C2=A0Wisconsin.
There = number is 1-800-826-6791.
=C2=A0=C2=A0= =C2=A0 All the Best,
=C2=A0=C2=A0= =C2=A0 LeRoy
BN?=C2=A0 Why would this be any = different from the DeoxIT in
our = application?
=C2=A0
Many = thanks for your brainstorming on = this.
=C2=A0
Bill = Norwood
U of MD at=C2=A0College = Park
=C2=A0
------------------------------------------------------------------------
From: = tap-l-owner@lists.ncsu.edu
[mailto:tap-l-owner@lists.ncsu.e= du] On Behalf Of Bernard Cleyet
Sent: Thursday, March 19, 2009 = 4:23 PM
To: tap-l@lists.ncsu.edu
Subject: = Re: [tap-l] Driven Harmonic Motion
Analyzer,=C2=A0PASCO, = Brushes
=C2=A0
I discover = I didn't attache the link.
=C2=A0
=C2=A0
On 2009, Mar 19, , at 11:09, Bernard Cleyet = wrote:
=C2=A0
Do not use = solvents! (I don't know the = geometry.)
=C2=A0
=C2=A0
I used = chalk on a motor-generator powering a Beta-ray
spectrometer (cylindrical = type).
=C2=A0
Here's a = rather detailed servicing of a motor generator. You
may be having a = problem w/ eccentricity. Note the instruction
for resurfacing. [Go to = cleaning slip rings.]
Note: improper pressure, if the brush is worn the = pressure may
be too low. I suspect proper pressure results in self =
cleaning. Is the ambience high = humidity?
=C2=A0
bc read = just enuf to think should send
=C2=A0
=C2=A0
On 2009, = Mar 19, , at 08:10, Bill Norwood = wrote:
=C2=A0
Hi = Taplers,
=C2=A0PASCO=C2=A0ME-9210A Driven FHM = Analyzer:
We must frequently clean the sliding = contacts,
which uses = up too much time and disrupts the = labs.
One contact is = carbon-to-steel (brush against rotating = shaft)
Other = contact is carbon-to-brass (brush against rotating
annular = ring)

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