Necklace that flips

My customer brought to me a necklace that had been created from a
flexable 4mm flat style chain with a 5.5mm bezel set diamond
soldered to both halfs of the chain in the middle. The chain is
soldered properly towards the top of the bezel.

It flips forward when she moves her neck. I believe that this is the
nature of this beast and nothing more can be done with it. I do not
believe lengthing the necklace so it falls lower would help, or
would it?

Anyone have any suggestions?

Thanks much,
Laurie

The nature of any necklace is to lie comfortably around owner neck
and follow any motion with natural suppleness. To achieve this
property, goldsmith must approach any necklace with a lot of
forethought and understanding of physics involved. The reason that
necklace flips is because it achieves the most economic mass
distribution in that position. In another words it was designed
badly.Few things can be tried, but none of them can be guaranteed to
improve things. Bad design rarely can be fixed at later stages of
fabrication.

One thing to try is to put necklace on necklace mandrel and work it
until it lies flat at each and every point. Another is to unsolder
bezel and attach it via flexible links. If there is variation in
flatness of soldered joints, it will trigger the flip, but to put
joints on the same plane is practically very difficult, so flexible
links is better solution. It may still flip after all this, so
client must decide if he/she wants to try to save the necklace, or
return to whoever made it for complete refund.

Leonid Surpin

As a shelf needs a proper supporting bracket, so your problem needs
a similar solution.

I suggest you add a circular loop of silver wire say 2mm dia
flattened when in the round, soldered to the chain back so it lays
flat on the chest, below the solitaire. I also suggest it is
eccentric with the larger part below the stone setting.

that will prevent it from tipping forward. No fee for this
solution!!.

Hi Laurie

I’d do a little tubular bail on the bezel set diamond and thred the
chain throught. I like the little tubes and they don’t flip back to
front. Barbara, on a little island where we have a multitude of
raindrops finally.

It flips forward when she moves her neck. 

I believe that this is the nature of this beast and nothing It needs
to be soldered around the top of the pendant, as you say. It also
needs to be soldered as near to the girdle line as possible, if not
above it. Center of gravity and all that…

It flips forward when she moves her neck. 

You know just reading this, makes me consider making a kinetic
necklace, that intentionally flips with a certain neck movement,
maybe revealing a message or a hidden stone… CIA

Hello Laurie, If when flat, the necklace forms a straight line; it
will never lie flat. Remove one side of the chain from the bezel and
reattach it so that the necklace is slightly “V” shaped. It will no
longer flip.

Have fun.
Tom Arnold

It flips forward when she moves her neck. I believe that this is
thenature of this beast 

That would be a dead nuts on assessment of that situation ! take the
opportunity to design something that she will love and does not flip
to gain a customer for life - goo

hi you could try a couple of extra jump rings between the fastners
connections this usually takes up the stress on the chain andgives it
a bit more movement. or you could also try altering the attachment
angles to the bezel a bit higher to alter its centerpoint a common
problem sometimes only remeied by fitting rings to the bezel as a
last resort.

ray blundell

I have had this happen before and I believe that if you resolder the
chain a bit so the bezel is weighted towards the bottom, it won’t
flip anymore. The other thing would be to put a little metal inside
and on the bottom of the bezel so it’s weighted that way it won’t
flip. It’s flipping because there’s nothing weighting the bezel in
place. Also, if the necklace is short, lengthening it might help.

I hope this helps and good luck.

Forgive coming in at the end… I assume this is probably a
Herringbone style chain that has the center bezel soldered in a 'V’
design in the center?

If I remember correctly this problem presented itself because the
necklace itself was too short and I believe we used to correct by
making it longer so that the design hung lower on the neck.

Sorry, it’s been a while since the repair days.

HTH.
MAK.

If I remember correctly this problem presented itself because the
necklace itself was too short and I believe we used to correct by
making it longer so that the design hung lower on the neck. 

Sometimes making it longer works, and sometimes it doesn’t. The
problem of flipping as follows:

Take standard chain of rectangular profile and 18 inches long. It has
right edge and left edge, both of the same length. Once such chain is
around a neck, the geometry completely changes. Instead of right and
left edges, it has inner and outer edges, and for the chain to lie
flat, these edges must be of different length.

Take 4mm width and 400mm length (approximately 18 inches). Inner edge
radius is 400 / 3.14 = 127.33mm, and radius of outer edge is computed
by adding chain width, which is equal to 131.33mm.

Calculating virtual length along the outer edge gives 131.33 * 3.14 =
412.38mm.

Since we only have 400mm the missing 12.38 mm have to be found
somewhere. Depending on type of chain and link flexibility, a chain
could accommodate by opening spaces between links on outside. It
depends on number of links and connection type.

Given 2mm link, it takes 200 links to make 400mm chain. To
compensate difference in length between inner and outer edges, links
have to be spaced 12.38 / 200 = 0.06mm, which is reasonable. Such
chain will not flip because there is no stress created along outer
edge. However if number of links halved, the requirement become
0.12mm, which most of the chains do not have. This creates stress
along outer edge, which makes inner edge pop up (chain is trying to
equalize forces along both edges). When person bends forward,
resistance created by contact with skin is lost and chain achieves
equalization by flipping at midway points.

Increasing length of the chain may reduce link space requirement and
prevent flipping. Here is why: 400mm chain with 4mm links must have
0.12m link space not to stress. Commercial chains usually tighter
than that. Let’s increase length of chain to 500mm. Inner radius
becomes 159.24mm and outer radius becomes 163.24mm. The difference
between inner and outer length will be 12.5mm. Number of links is 125
and link distances will be 12.5 / 125 = 0.1mm. So by increasing
length of the chain we reduced stress by 20%, and increased weight of
the chain is also beneficial in preventing flipping. Wether or not it
is enough will depend on weight of pendent and geometry of
attachment. To make the long story short, the stress may be present,
but it may not be enough to flip. The necklace will only flip if
forces generated by stress is enough to overcome weight of pendent
and in some cases the weight of lower half of the chain.

It should be clear from the above, that all these issues should be
dealt with in design stage, rather than in post-fabrication.

Leonid Surpin