[CAUT] Fwd: Does V S Profelt work in reverse?

[Mark Cramer]

I don’t know about the sizes in general David, just that initial (20 ¼).size
that many new parts come with. It’s likely a European standard. (?)

 

That’s not my beef though, (catch my last post) it’s the loose initial fit
of new parts. I can accept a supplier suggesting for instance that “their
standard is 1.8 grams”. 

 

Fine, I can work with that; if I want firmer, I’ll have to re-pin. However,
if I decide to work with the low friction, but the 1.8 grams ends up being
.5 grams or less before I even have the action buttoned up, and the pins are
walking by the end of the first semester


 

What I honestly hope for every time I have to repin new parts with the
.05025” pins David, is that I can simply go ¼ size to a #20 ½ (.0505”)
without any reaming or burnishing, get a perfect result, and all would be
forgiven. But it hasn’t happened yet.  

 

Regarding the inconsistency from side to side, I wanted to ask Roger if he
thought the *channel* might snag the bushing on the way in?  (yeah, I just
stopped to read Ron’s post.)

 

BTW, we have a little bench jig with a spring clamp that we use for testing
every center after re-pinning. I find it easier to make sure a center is
really firm, if I can quickly clamp the flange to something solid, then
grasp the shank about 1/3 of the way up and flex it side to side.

 

I’m indebted to my colleague Bert Picknell at the Banff Center for
demonstrating how much more sensitive a flex-test at a third or halfway up
the shank is, than at the very end.

 

Mark C.

 

PS Thanks Ron, I’m still in denial about what’s happened to the old
eye-sight in my 45th year. I had to hold the flange at full arm’s length
just to see whether the ends of the pins were polished or machined. Will
have to take your word about the channel until I can get over to the dollar
store fro a pair of them “readers”

 

  _____  

From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf Of David
Ilvedson
Sent: April 8, 2009 8:17 PM
To: caut at ptg.org
Subject: Re: [CAUT] Fwd: Does V S Profelt work in reverse?

 

I would seem the idea was to keep the center from walking, even if it was
too small for the birdseye.   Mark, do you find the Renner centers are in
between our center sizes?   I'm consistently finding tight on one side and
loose or Ok on the other...

 

David Ilvedson, RPT
Pacifica, CA 94044

  _____  

Original message
From: "Mark Cramer"  
To: caut at ptg.org
Received: 4/8/2009 6:02:07 PM
Subject: Re: [CAUT] Fwd: Does V S Profelt work in reverse?

A few years back I did a side-by-side comparison of CLP, Methanol and Wally
Brook’s mineral oil/naptha mix.

 

I was hoping to find a calibrated approach to ease those new centers that
are frozen right out-of-the-box, but swing wild the moment you treat them
with anything.

 

Unfortunately, short of meting out a micro-dose, there was no clear winner.
So I decided that to have a long, happy life with a set of action centers,
the safest bet was to treat them with CLP anyhow, and find out what I had
really paid for. Then, re-pin them to the (seasonal) friction I was after. 

 

My feeling is that some manufacturing processes result in an initial
(rotational) friction that is more a result of cloth tension than density.
So, when I take a new flange that won’t swing, hit it with some CLP, and
immediately it releases into 20 swings, the picture I have is of a bushing
coiled tightly around the pin, suddenly loosing its grip and releasing like
a coil of piano wire that
 oops.

 

I believe Wally once told me that Herberger-Brooks bushed parts were spun on
a long polished pin, against a fixed object, until the cloth was burnished
enough that the part fell off the end of the pin. Even if that method is no
longer in use, I’m wondering if even forcing/twisting in the long pin for
gang-bushing might twist the cloth and impart some tension. (?)

 

Anyhow, while I sit here and ponder all this can anyone explain the
necessity of that ridge/burr at the center of a Renner center-pin? 

 

Do we really need it to keep the pin from walking, or is it a self-destruct
mechanism designed to tear out the bushing, and keep the clever parts
counterfeiters guessing? (and just how long until the clever imitators learn
how to spell RENNER so they can laser it onto their very own dimensionally
correct product! ;>) 

 

Best regards,

Mark Cramer, RPT

Brandon University 

 

   

 

 

  _____  

From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf Of Tim
Coates
Sent: April 8, 2009 6:22 PM
To: caut at ptg.org
Subject: Re: [CAUT] Fwd: Does V S Profelt work in reverse?

 

Fred,

 

I concur with your findings.  I did the same test you did and obtained the
same results.  I wonder how others are applying the VS Profelt to increase
the friction?

 

Tim Coates

 

  

On Apr 8, 2009, at 11:06 AM, Fred Sturm wrote:

 

On Apr 6, 2009, at 11:33 AM, DCyr141833 at aol.com wrote:

 

Also am finding that it works ok on new action part centers that have 0
grams friction - hammer flanges and whippen flanges.

 

            This statement raised my eyebrows a bit, as it certainly doesn't
make sense based on my previous experience. So I tried it this morning on
four hammershanks (Abels). I didn't have any at 0 grams, but all four were
at about 1 gram. I applied a drop to each side. Three hours later, all four
are at 0 grams: the flange flops nicely in the breeze (hold the shank and
swing the flange, and it goes back and forth a couple times). So I would
strongly recommend against this application, myself.

Regards,

Fred Sturm

University of New Mexico

fssturm at unm.edu

 

 

 

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