Saturday, June 30, 2012

Tattomashine.The Springs


2 steel springs (in our application), when bent, serve 2 main functions: 1) They create
a resistance to the ‘downward’ pull that the coils exert on the armature bar, by
pulling the armature bar in the opposite ‘upward’ direction (rear spring) & 2) Control
the speed (front spring) and force the armature assembly will bounce back (after making
contact with the contact screw) to the coil (with the aid of the coil’s magnetic pull).
Springs usually are used in pairs; a rear spring and a front spring. Though a “one piece”
spring may be used (p. 51), the spring “pair” combination produces greater variability
and versatility in the intended uses of the machine and each (spring) has it’s own job to
do. Machines usually use a pair of springs, a front and a rear spring. These springs are
usually made from “close grain high carbon spring steel” or “strapping steel”. An excellent

example of a high cuality spring steel is found in automotive “feeler gauges”.

This is a set of feeler gauges ranging from thick to paper thin. These are generally used
for gapping spark plugs, another example of spring steel can be found in the steel
“straps” used to hold 2x4’s together, usually in shipping. The strapping steel has a ‘blue’
look to it, the steel these straps are made from are treated. This treatment affects the
rigidity of the material. Generally, springs made from this ‘blue’ steel, feel harder and
have less flex than a “feeler gauge” spring of the same gauge. Simply put- a blue .018
gauge spring usually will feel stiffer than a feeler gauge non-treated .018 spring. If you
have this type of spring as your only option, experiment with shapes that improve flexibility,
if the spring is too stiff (see “Spring width and shape” section p. 25). Be sure you
test the flexibility of the material before using it as a spring for your machine. Hold a
piece between both hands, about 1” between your thumbs and place your pointing fingers
on the ends of the material and bow it, see if it springs back. If it doesn’t spring
back and stays bent, it is not worth using as it may crack, or not have the resistance
needed for a smooth running versatile machine. Using low quality springs can cause the
machine to sound and run exactly the same way it would if there were electrical powersurges
going through it.This is a set of feeler gauges ranging from thick to paper thin. These are generally used
for gapping spark plugs, another example of spring steel can be found in the steel
“straps” used to hold 2x4’s together, usually in shipping. The strapping steel has a ‘blue’
look to it, the steel these straps are made from are treated. This treatment affects the
rigidity of the material. Generally, springs made from this ‘blue’ steel, feel harder and
have less flex than a “feeler gauge” spring of the same gauge. Simply put- a blue .018
gauge spring usually will feel stiffer than a feeler gauge non-treated .018 spring. If you
have this type of spring as your only option, experiment with shapes that improve flexibility,
if the spring is too stiff (see “Spring width and shape” section p. 25). Be sure you
test the flexibility of the material before using it as a spring for your machine. Hold a
piece between both hands, about 1” between your thumbs and place your pointing fingers
on the ends of the material and bow it, see if it springs back. If it doesn’t spring
back and stays bent, it is not worth using as it may crack, or not have the resistance
needed for a smooth running versatile machine. Using low quality springs can cause the
machine to sound and run exactly the same way it would if there were electrical powersurges
going through it.
24
Understanding spring gauges
The smaller the (standard) number on the spring stock, the “thinner” and more flexible
the stock, the larger the number, the “thicker” and less flexible the spring stock. A
machine will have to work harder to move a harder (thicker) spring (.019, .020, .021)
because the flexibility is limited, this can also happen when there is too much tension on
the rear spring. Generally, spring gauges used are inch measurements, the number .018
has an equivalent metric measurement of .457. A .017 spring has a metric equivalent of
.432, so in metric, it is the same, the greater the number, the thicker the spring gauge.
An .018 in front used in combination with a .017 in back may be ideal for the proposed
function of your machine. Maybe the drilling specifications on a particular frame may
require the stiffness of a .019 rear spring and a .018 in the front. The tension of the rear
spring will dictate the amount of compression on the front spring which, in effect control
the speed of armature bar/needle bar movement and force of needle penetration...
that is, if the front spring is a thin enough gauge to have some flex, and it should have
very little. If it doesn’t, it may be too thick of a gauge, we recommend to stay around .017
and .018 for a front spring (see Spring Tension test p. 60).
Remember, the power supply controls the force at which the needles will penetrate (not
the speed) when encountering resistance from the skin. When doing a black and gray
piece, a machine may run at a lower setting (on power supply) on the customer with softer
skin (to achieve a smooth perfect gray) and may need to run at a little higher setting
on someone with tougher skin, in order to achieve the same “smoothness” of shading.
The tension of any spring is affected by it’s thickness / gauge and will directly influence
the quality of penetration and resistance the needle grouping will encounter, controlled
of course by the regulated power supply. The goal is to regulate tension, (bend), gauge
of the springs, in conjunction with the pull from the coils magnetic field, which is controled
by the power supply’s dial.
You can make these springs yourselves or buy them already cut. To make springs, see
the “Cutting Springs” section, Chapter 4 - p. 29.
Spring / Armature bar assembly
The assembly of a spring / armature bar set up is as follows— bottom to top: armature
bar, rear spring, front spring, washer, screw.
TIP-any washer used directly on top of a spring should have any sharp edges gently filed
off, this sharp edge can increase the risk of a spring breaking in the particular area the
sharp edge pushes into the spring material, the movement of the armature bar and the
flex of the spring material, will speed up the breaking process.for proper function will vary according to the specifications
of the tattoo machine and weight of the armature bar / components associated
with the armature bar. Generally, we recommend a .017 or an .018 front spring and a
.018 rear spring combination...though different gauges may be used to compensate for
differences in frame design and drilling specifications, or weight of the armature bar.
The flex of the .018 spring (usually) has the standard ideal flex / stiffness for a perfectly
versatile and well tuned machine. Though, on occasion, an .018 may be a little stiff for
a rear spring if the spring saddle is very close to the back of the armature bar, where a
.017 gauge spring may be the ideal gauge to use. Generally, springs used will remain
between .017 and .019 for the rear spring and .017 and .018 for the front spring.
Spring width and shape
*A question: You have 2 pieces of spring steel stock, both are identical in thickness and
in width, but one is longer, which one will be harder to bend? The short one will be
“stiffer” and have less flexibility when bent by holding each end, the longer one will be
more flexible. This principle is important because in the tattoo machine application,
tension on the springs is created by bending or un-bending the springs, or
shortening them. If the distance between the spring saddle and the front of the armature
bar is too great, and the gauge of “rear” spring stock is not thick enough there will
not be enough tension / leverage to move the armature bar at a force acceptable for
proper needle penetration in to the skin, no matter how big of a bend you put in the rear
spring; remember the rear spring has to deal with the following: armature bar weight
(including it’s assembly components), needle bar weight, grommet weight, rubber band
tension, how many needles must be forced into the skin and the skin type. A thicker
spring gauge may be considered if needle penetration is not adequate.
*A second question: You have 2 pieces of spring stock, both are identical in thickness
and in length, but one is thinner in width, which one will be more flexible? Easy.
Using this principle, solve this problem: You have a rectangular piece of spring stock
which needs more flexibility. What could you do to this rectangular piece of stock to
increase flexibility? Change it’s shape-cut, file, hole punch...removal of stock on each
side of the spring will increase flexibility and reduce tension, as will removing stock from
the center (See illustrations on the next page).
This seems so simple yet a big percentage of artists cannot diagnose this
problem and would not know how to fix it. Do not be afraid to experiment
with different shapes and thickness of your spring stock. The springs are
possibly the most important ingredient in the function of a smooth and versatile
machine.

Spring Tension
Some artists say that bending springs may shorten the life span of the spring and cause
it to break sooner. We have all seen the armature bars with angles milled into them to
accommodate an unbent front spring. The same could be done to the spring saddle to
accommodate an unbent rear spring. The theory stating that “bends in the spring will
shorten the material’s life” may be true but we have no choice unless we use angled
spring saddles and angled armature bars. If you don’t use those bars, you must regulate
the tension on both springs by bending or unbending them. Another point to bring up
regarding these armature bars with angles milled into them, even though they are a
novel idea and very inventive (invented by Bill Baker of Eikon Device in Toronto,
Canada), it’s important to state that these require 2 screws and or 2 washers to secure
the springs to them…this adds weight to what the rear spring already has to carry and
may require a thicker rear spring gauge to move them correctly, so keep this in mind if
this your choice of armature bar, use the correct spring gauge!

Remember, the tension on the rear spring will decide the compression of the front
spring, and that the front spring will compress according to it’s gauge, the thinner the
front spring, the more flex it will have. This directly affects the application of the tattoo.
The gauge of the front spring is just as important as the gauge of the rear spring. The
front spring partially influences the movement of the armature bar which directly affects
the needle bar’s force of movement. So a thicker stiffer spring may work well for lining
with larger groupings as it causes more counter resistance than a softer, thinner spring
would, but it can also determine the abuse the skin may have to endure if there is not
enough flex to deal with the resistance the skin will produce against the penetration of
the needle groupings. A stiffer front spring will also limit the versatility of the machine’s
function to a strictly coloring machine or a power liner but will also make the machine
have to run at a higher setting on the power supply and may even cause the machine to
heat up. The technique to gray shade consistently and smoothly by turning the dial on
the power supply “down” will not work properly if the springs are too stiff, and if there
is too much tension on the rear spring. We believe that each machine should have the
capability to outline, shade and color with the particular grouping being used, including
a single needle. This enables the artist to excecute small tattoos with the same detail as
a larger tattoo, provided that he/she has the skill to use small needle groupings.
This brings up another problem. Being familiar with the armature bar and it’s
assembly, answer this question: You have a .016 or a .017 spring in front (these gauges
are used as an example based on the understanding that the .018 gauge spring is the
“ideal” standard spring to use) you can use the machine just fine with a 5 or 7 magnum
for black and gray shading or lining with a single needle and a tight 3, but cannot use a
larger liner grouping to line with it or color solidly with it, what would be the cause?
The resistance of the needles penetrating the skin causes the thin .016 or .017 front
spring to flex thus allowing the needle bar / grouping to “back off” from the skin upon
contact, and not allow the needles to penetrate the skin deeply enough to inject the color
solidly. You will need that front spring to be stiffer and don’t have and .018 to change to,
what can you do?... using the principles described above. Shortening the front spring by
cutting it and move your contact back is one way (be sure to set your stroke and tune the
machine after cutting the spring and moving the contact screw back) , why? Because a
wider, shorter spring stock will be less flexible in terms of leverage—front to back--tip of
the spring to the back where it is secured to the armature bar.
What else could you do? O-rings come in a variety of thicknesses and diameters. When
placed under the front spring and over the armature bar assembly screw or under the
front spring and behind the back of the armature bar, the ‘pull back’ on the front spring
can increase tension. A thicker o-ring will move the point of flexibility closer to the tip
of the spring thus shortening the available spring stock and increasing tension (lessening
flexibility) on that front spring. Though ideally, the spring should be changed to a
thicker gauge and an O-ring added. O-rings provide a shock absorber under the spring
and make for a smooth running machine-careful with the thickness of the O-ring.
When modifying a thicker spring gauge by slimming it down (removing stock in order
to increase flexibility and lessen tension) the flexibility of the .018 gauge spring usually
has the ideal flex to move and support the weight of the armature bar, it’s assembly components
(screw, washer, front spring, o-ring, grommet/tape/paper towel, needle bar,
needles) as well as resistance from the rubber band and the resistance from the penetration
of the needle grouping into the skin-suntanned or tougher skin will affect counter
resistance on the front and rear springs as well. The front spring deals mostly with the
resistance from the penetration of needles into the skin, more so than the rear spring,
though the rear spring is also affected. …why is your machine heating up? Maybe you
should check the gauge and tension of rear spring. Or maybe your rubber band is too
tight. Similar to an overheating car, a machine can heat up if it’s struggling to move the
armature bar due to increased resistance (too stiff of a spring, too much rubber band
tension and weight of the components (armature bar assembly). A machine heating up
may be a symptom of another cause as well…carbon build up on the contact screw interferes
with the flow of current and makes the machine work harder. It can also build up
on the clips on the clip cord, so watch for it and remove it if necessary. From constant
use, the metal clips will develop wear in the form of grooves worn into them, these can
be filed down to smooth these out but eventually, the clip cord clips should be replaced.
A clip cord is easy to build and maintain, as is the footswitch.





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