[AMRadio] Best product for noisy potentiometers?

Mike Sawyer w3slk at verizon.net
Tue Apr 23 13:47:57 EDT 2013


Don (et al),
    They probably instituted keeping syringes under raps because of illegal 
drug use. That being said, you can get blunt tip syringes fairly easy. These 
are the ones that are not designed for intravenous injection but used for 
'irrigation' in the ER and other medical departments. They can get pretty 
fine without the worry of being stuck since there isn't any taper to the 
tip.
Just my 5 cents.
Mod-U-Lator,
Mike(y)
W3SLK
----- Original Message ----- 
From: "Donald Chester" <k4kyv at charter.net>
To: <amradio at mailman.qth.net>
Sent: Tuesday, April 23, 2013 1:39 PM
Subject: Re: [AMRadio] Best product for noisy potentiometers?


Something I have found very useful for injecting lubricant or contact
cleaner inside hard-to-reach places like the interior of a potentiometer, or
a single tab on a small rotary switch, is a medical needle/syringe assembly.
My wife is a nurse, and she used to be able to bring home as many (unused!!)
ones as I wanted.  But then the place where she worked decided to start
treating them almost like a controlled substance, and she would have got in
trouble for taking one out of the  building.  I think they can be ordered
on-line but I found a readily available local source, for a syringe and
package of 5 needles, all for about $3 at the local farmer's supply,  in the
animal care section. The ones sold for veterinary use  are identical to
human ones at probably a  tiny fraction of the price, and come in different
sizes.  They smallest size is 22 gauge, and the largest, 16 gauge, close to
corresponding wire gauge sizes.

The smallest size is ideal for stuff like WD-40 and de-oxit, because you can
inject a tiny drop just where you want it to go.  I have even used the
larger size for epoxy. I have a can of epoxy thinner and this works best
when it is thinned down to a fairly runny liquid, although I have succeeded
with the stuff at honey consistency. I think they make even larger  sizes,
but the local store only carries up to #16.

Depending on the job, the needle sometimes works best if you file off the
bevel tip, but you will probably need a small object that will go inside the
needle tube to de-burr it, since the burr will inevitably stop up the tube
at the end where you filed it.  Of course, when using it for epoxy, the
needle and syringe become a one-use item.  Also, be careful with certain
solvents.  I one had a plastic syringe to dissolve right in my hand while I
was attempting to use it.

Don k4kyv





More information about the AMRadio mailing list