Back to Ganoksin | FAQ | Contact

How Vigor RN-515 is used?


#1

Someone gave me a VIGOR RN-515. I’ve seen these before. How is it
used? I have all (I assume) the little wheels too.


#2

Its actually a specialised miniature rolling mill designed
specifically for rolling ring shanks to enlarge rings.

The “wheels” are rollers with different size/shaped grooves in them.
Choose a roller with a groove that matches the shape of the ring
shank, pull out the pin that holds the roller/gear assembly, replace
the existing roller with the one you have chosen, then replace the
assembly and pin.

Unscrew the handle until you can place the ring over the central,
fixed, post, then screw the handle in until the grooved roller is a
nice snug fit on the ring shank. Rotate (swing) the handle about the
centre post to roll the roller around the ring, and the pressure of
the roller will squeeze the ring shank to make it thinner and longer
and increase the ring size. Screw the handle in to increase the
pressure.

Be aware that the action is very aggressive and it is VERY easy to
overdo it and make the ring much too big. Do it a little, remove the
ring and check its size often.

Its a useful bit of kit. You can also use it to make D-shaped wire.

Regards, Gary Wooding


#3

Bobb,

The Vigor RN-515 is exceedingly similar to the ring stretcher sold
by Esslinger.

These machines accept rings with settings and can expand them without
influencing the setting. Using a roller of correct profile, you can
progressively roll the plain part of the shank to extend it.

Mark B
Fourth Axis
http://fourth-axis.com/


#4
Rotate (swing) the handle about the centre post to roll the roller
around the ring, and the pressure of the roller will squeeze the
ring shank to make it thinner and longer

Very timely! As it happens, I came across one of these where I teach
and tried it out just today. When I swing the arm around, the ring
stays in the same position relative to the moving arm, just rotating
around the inner post, so all it does is make a ding in one spot. I’m
not strong enough to hang onto the ring and keep it stationary
relative to the central post so that the arm travels along the ring
band. What am I doing wrong?

Noel


#5
When I swing the arm around, the ring stays in the same position
relative to the moving arm, just rotating around the inner post, so
all it does is make a ding in one spot.... ... What am I doing
wrong? 

Don’t crank the “micrometer” handle down so much. Start with light
pressure so it’s only rolling the shank a very little bit. You want
it putting just barely enough pressure on the shank so it’s actually
stretching it a little. If the pressure is so much as to actually
dent or ding the shank, it’s too much. If it needs more stretching,
increase the pressure just a little more and roll again. You can’t
take too much of a bite on one pass. Also, while tools in general
like being oiled, the center post on these things is an exception.
Make sure it’s clean and dry. By the way, taking only a slight pass
at a time with these stretchers is a good idea in any case, because
even a slight reduction in thickness of the shank can give you a
surprising amount of increase in ring size. It’s very easy to
overshoot the desired ring size. So just a little bit at a time, with
frequent checking of the ring’s size as you go. Doing it just a hair
at a time also helps you to feather in the rolled reduction so you
don’t get a strong step in the shank at the shoulders. On rings with
a tapered shank, start with pressure settings that don’t even contact
the shank at the bottom, but only just hit it where it reaches the
desired spot at the shoulder. Roll that part slightly on each side.
check size. Then again, slightly more pressure, but not rolling up
the side quite as far, etc. In many cases, you can stretch a ring a
substantial amount by only rolling the sides like this, so you don’t
have to reduce the shank’s thickness at the bottom, where it’s
thinnest, at all.

Again, the basic answer to your problem is “easy does it”. And be
careful. These stretchers are quite capable of doing a whole lot of
damage if you’re not careful. Go at it gung ho, and that size five
ring you wanted to stretch up to a six, will suddenly turn out to be
a size 10.

Peter Rowe


#6
When I swing the arm around, the ring stays in the same position
relative to the moving arm, just rotating around the inner post, so
all it does is make a ding in one spot. I'm not strong enough to
hang onto the ring and keep it stationary relative to the central
post so that the arm travels along the ring band. What am I doing
wrong? 

It would appear that you are missing a vital part. There should be
two little gear wheels under the fixed and moveable rollers: a fixed
one under the flat roller on the central post, and a removable one
under the changeable roller. The removable one has a little peg in it
that engages with a hole on the side of the changeable roller; its
purpose is to “lock” the gear and roller together.

When you screw the handle in to squeeze the ring, the two gears
should mesh together. When you rotate the handle the removable gear
rotates around the fixed gear which, in turn, rotates the roller. The
ring shouldn’t slide on the fixed post and it shouldn’t be necessary
to try to keep it still; the action caused by the meshed gears should
simply roll the the outer roller (the removable one) along the
circumference of the ring.

If both gears are present has the little peg broken off?

Regards, Gary Wooding


#7
When I swing the arm around, the ring stays in the same position
relative to the moving arm, just rotating around the inner post, so
all it does is make a ding in one spot. 

A couple of suggestions. First, you probably already did this, but
for the sake of thoroughness, make sure you are using the closest
matching die. No matter which die you start with, it won’t be a
perfect match. Because of this, at the beginning the profile die’s
ability to grip the ring shank is very limited so you have to be very
gentle with tightening the gap. Go back and forth a few time and
once the shank is more firmly seated into the profile, you can be more
aggressive.

It’s also important to hold the ring level as you swing the arm back
and forth. FInally if you happen to have one of the lower cost
knockoffs, be aware that the inner die and the outer profile die are
not as parallel as they ought to be. TO a certain extent, you can
compensate for this by frquently flipping the ring.

ed