fiber glass pencil & corroded contact terminals

[Kiriakos GR]

Share with the community your satisfaction level with those fiber glass pencils.

Personally I am a fresh owner ( six months old),  even show I have start to appreciate those pencils.

I got the most of their performance by cleaning gold plated contacts ( Digital camera memory cards), and softly corroded battery terminals (NiMH battery chargers). 

[Phyllomedusa]

Oh yes. You will really like these pens if you have to rework some corroded equipment.
As lots of our equipment runs automated in remote areas in Ecuador or French Guyana and isn't serviced you may guess how it looks when we bring it back home
The contacts are mostly gold plated but these show corrosion as well. As fibre pens helps a lot to clean them up.
For my camera I never needed one (Compact Flash)

[Kiriakos GR]

I just found one better picture from the pencil that I own.
It is a picture taken by me, I have post it in another forum and never kept a local copy. 

[Astroplio]

Hmm that is an interesting tool, I haven't heard of it before!

So how do you use it? You just brush gently over the contact you want to clean and the fibers take away little by little the rust/contaminants? Do you apply a solvent or you clean with a dump towel?

If I understand correctly it is a highly enhanced version of the humble toothbrush but with glass fibers instead of nylon ones?

Anyhow, it is a cheap tool, might as well get one on next chance, sure it will come handy for anyone working with electronics or even computers.

[Kiriakos GR]

Nice question, 
the key adjustment of this tool comes by controlling the free length of the glass fibers.

When this length is set to 1.5-2mm the glass fibers become hard enough to remove the hardest built-up corrosion.
The idea is that the glass fibers is capable to act as one knife which at the same time is incapable to damage or pollute the surface which needs cleaning with metallic particles (metal to metal abrasion).
In this setting the tools works as a pencil, and not as to was a brush.   

When this length is set to 3-4mm the glass fibers become a bit softer and they are almost capable to remove soft corrosion caused by a finger print over a gold plated surface ( Memory cards). 

When this length is set to 5-6mm The pencil has turn in to a brush which is capable to remove light corrosion, for example the one that is built-up in CPU sockets.

When the length of the fibers is more than 6mm it stops to act as abrasive and stops to be useful.
At this setting the fibers are capable for allot free play and it is possible to break off.

About the example with the tooth brush, just think this analogy: 1 Tooth brush hair =  8 glass fiber ones. 

   

[Astroplio]

Aha! That makes more sense now, thanks for the follow up!

Are those fibers eaten away rapidly? Lets take the case of a corroded AA battery terminal, is it possible that you have to use a whole brush just for that, before you need to replace the brush on the pencil with a new one, or the lifetime of the brush is much more than that? (A rough estimate).
Well, to make it more clear, in the bottom line, what I ask is how many replacement brushes should one keep in his toolbox at a time :-)

thanks!

[Kiriakos GR]

Those pencils are capable to clean just the surface of the metal from carbon deposits or soft surface corrosion, if the problem is large = the surface of the metal is not intact any more due corrosion by chemical agents, or burned-out due excessive sparks.
I this case the pencil is incapable to assist.

About the life expectancy of its one replacement( fiber cartridge), I will speculate that it will serve for 150 uses (repairs).

[Astroplio]

OK got you!

[Kiriakos GR]

So far I have use it with great results at:
a) Smart media memory cards ( Olympus camera)
b) Cell phone card
c) NiMH batteries and  battery contacts (battery housing)
d) INTEL CPU socket
e) Test leads ( tips cleaning)
f) PC Memory, gold plated contacts

Yes it does worth getting one. 

[Kiriakos GR]

I had started this topic at 2012,  now in 2015 even me I feel more wiser and have a tip to share by the picture bellow, this is good as demonstration of new cleaning applications for this fiber glass pencil in the sector of electrical test leads, and even for oscilloscope probes.

For me this pencil in the world of mOhm measurements with my LCR meter it did save me from frustration many times.
LCR Twizzlers is a sensitive tool and part of the big picture which called as accurate measurement, when there is unseen to naked eye accumulation of dirt, this it can damage the measurement. 
The cleaning of the contact area it does restore the tight specifications of this Twizzlers to their original value.

The oscilloscope probe tip point is another sensitive contact area, this add-on hook clip accessory which stays over it most of the times, it does cause soft oxidation, in my probes I did noted the creation of a black ring of dirt over the probe tip.
And again this fiber glass pencil saved the day.

Regarding alligator clips which are used in battery inspection and charging applications, it is very possible your clips to become contaminated by dry particles of battery acid.
This acid dust among with environmental humidity it will start damaging first the contact area of its individual teeth and this corrosion eventually will spread all over the clip.

In the world of car batteries this contamination with battery acid of any tools that touching the battery is a common problem.
Large size alligator clips they should be washed with soap water immediately if they come in contact with wet battery acid.
At normal use it is best those large clips to be cleaned after its use by a cloth which this have previously accumulate a portion of burned cars engine lubricants.

 
     
 

[Kiriakos GR]

I was unaware of how many scumbags they get involved, at making fiber glass pencil. 

I ordered one unbranded for eBay Europe, and I received a trash ....  it makes squeaky sounds when rotating top cover.
This came with a single refill, which seems as impossible to remove, with out permanent damage of the axle. 

So here is the story about these pencils.

There is top class of such pencils for professionals at watch & clock repairs
This is German production, not branded all times.  Brands selling tools for watch & clock repairs shops, they also carrying them in their catalog.

Second best .... fiber glass pencil branded, for the market of plastic and metal models, trains and airplanes.
The Chinese they cannot cheat here,  European importers add their brand and retail packaging,  while the pencil  mechanism seems perfect, smooth motion, the plastic axle holding the refill, this has Max life cycle of 7~8 years ( inner hard plastic degrades).

Third and last ....
What ever a Chinese factory can make so to cheat consumers.
Single pencil with refill = production cost 0.15 $ USD,  6 EURO at eBay (about 8 EUR with shipping).

After this new lesson, of four wasted Euros at eBay, I will also honor this Made In Germany design for professionals.

As soon I will complete this purchase, I will post more details. 

[Kiriakos GR]

Third and last ....
What ever a Chinese factory can make so to cheat consumers.


Here is of how they do it. 

1) Inner axle gets in place from the back with a hammer.
Outer plastic this is weak to tolerate the hammering, red plastic this gets white when crashed.
This pencil its full of crushing marks. 

2) They cheat at the refill, by using almost 30% less of fibers.
New refill this is covered with glue, and appears normal.
When you give a bath at this refill with plain water ( this is the recommended method before use), the glue gets away, and you have an 3mm refill instead of a 4mm wide refill.

3) Portion of glue, of a fresh glued refill, this gets in the refill holder.
They do not even wait so the refill glue, this to dry out.
The outcome... this refill base, it gets also glued over the refill holder.   

It is from the rare times that I do upload straight from the camera.
Select image, open in a new Tab,  and enjoy the Chinese technology of 2026.