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K-Model Machine Tune-up

Tattilac Tune-up;
How do you know when your machine is tuned up? Most tattooers I talk to say they can’t tell me how they know, but they know it when they have it in their hand, and they’re probably right. In reality, knowing what makes a good tune-up is to understand a theory, not necessarily controlling every component in every way. There are so many variables to how a tattoo machine will run, and so many techniques on getting the pigment into the skin, it becomes impossible to pin point a specific tune up setting as the only one that is perfect. But, understanding this theory will help you run your machine with the right stroke length, and use the right needle group, for the artistic and technical effect you desire.
This tune-up procedure is described as though you are an experienced professional familiar with the tune-up procedures and requirements of a typical fixed spring tattoo machine. If you don’t know how to tune a machine, that’s fine, after reading this you’ll know how. Tuning a K model machine is similar in theory and is basically the same as tuning a fixed spring machine, but in reality is more simple and easy to do. Figure M1 and fig. M2 are illustrations showing the components of a complete tattoo machine, and the physical differences between a fixed spring machine and a K Model machine.

Fig. 1
The Swivelhead design is what distinguishes the K model Tattool machine from an old style fixed spring machine. The swivelhead, binding post swingarm, front and rear spring and armature bar swivels to reposition the spring and armature bar into any position you choose.

K model machines are almost exactly the same dimensions as all other respectable machines. The only difference is the range and ease at which it can be tuned.

The Worlds First fully adjustable Tattoo Machine.

The Swivelhead was invented by Kelly Miller in 2003
Patent Pending

Fig. 2 Some machine manufacturers have set the spring saddle at a verity of different angles, all trying to get the perfect angle that allows the machine to operate properly without having to bend the springs. This figure represents only the basic and most common situation.
A fixed spring machine is any machine that can not be retuned without bending the spring. I say retuned because the machine may run fine to some degree, just the way the manufacture set the spring saddle when they originally designed the frame. But most brand new fixed spring machines need to be fine tuned to the style and technical effect desired by the tattooer. In order to tune a machine that has a spring saddle that can’t be changed, the spring has to be bent to get a different stroke length. But, when the spring is bent to achieve the proper stroke length, the spring tension changes, it usually increases beyond the actual needs of the spring. Fixed spring machines are also known to have the front binding post arm attached to the frame in a fixed position, which means the stroke length is very limited.
This diagram represents a K model machine that has had the stroke length increased by adjusting the swivelhead assembly. Adjusting the spring in this manner, increases the stroke length a precise amount. While not changing the tension of either spring, or the angle of the front spring. The point screw adjustment range stays the same.
This diagram represents a fixed spring machine that has had the stroke length increased by bending the main spring. Bending the spring in this manner, increases the springs tension in an unpredictable amount, which means you have to deal with what you get, there is no going back once you have bent the main spring.
Bending the main spring also shortens the distance between the arm-bar and the binding post. Because the binding post arm on a fixed spring machine does not move, this shortens the range the front spring has to create a harmonic balance, which make these machines very hard to properly tune to begin with, and practically impossible to repeat a tune up. It is because of these limitations, fixed spring machines have never been able to properly run large groups of needles.

This tune-up procedure works for both shader or liner machines, they are both about the same depending on the technical effect applied. The voltage or your technique may be the only difference between a liner or shader machine.

In this case a 0.150 thousandths of an inch will be the stroke length, this is the distance between the armature bar and the coil post. (And remember, machine stroke length is different than the depth the needle penetrate into the skin. We’ll talk about depth of skin penetration later.) This stroke length works well for me as a - liner/shader - machine. I primarily run 14 rounds, 33,44, and 45 superflats with a stroke this length. But sometimes I’ll use this machine with a 7 round for shaded detail, or turn up the power, just a little, and work off the tip of a 3 round for precise detail. On the other hand, I will sometimes use this stroke length with a 60 or 75 needle superflat for solid to soft shading. This is a good all-a-round stroke length. Start with 18 volts and adjust the power up or down a little at a time until you have the right power for the skin condition. You can use this machine for just about any style or technique possible. Although a slightly shorter stroke makes better hard lines and solid shading, while a longer (0.150) stroke will help make soft shading a breeze.

Here is a description of the machine and components that we’ll be talking about. The machine has; 8 wrap x 1 1/4 x 3/8 core coils, 9 gram #3 armature bar, two piece 1/2w x 20 gauge springs w/ contact point, a 47 UF 35 volt capacitor, and one # 12 rubber band. The machine also has a 0.150 thousandths of an inch stroke length, with a K model superflat tube tip, with ink, on a 45 superflat needle group.

We’ll start the tune-up with the machine in your left hand, with needles on the left and the front binding post arm against the palm of your hand.
# 1- Loosen the point screw until there is a gap between the screw and contact point. Hold the machine in such a way that you can apply a slight amount of finger pressure on the top of the front binding post arm. See figure M4A.

(Applying slight finger pressure on the binding post arm, see fig M4A, assures smooth and precise movement when the bottom binding screw is loosened or tightened.)
#2 - Loosen the swivelheads top binding screw, fig M5B, a full turn or so, enough that the screw doesn’t contact the machine frame during the next adjustment.
#3 - Loosen the bottom binding screw, fig M5C, enough to allow you to gently pull the front binding post arm, fig M4, towards the coils until the armature bar slightly contacts the coils core.
#4 - While holding the machine as described above, with needle bar and tube in place as though the machine is ready to tattoo. Reposition your finger to hold the armature bar against the front coil post, fig M4B, and adjust the tube so the needle points are protruding from the tube tip the length you want the machines stroke length to be. In this case the amount of needle protruding from the tune tip should be 0.150 thousandths of an inch. fig. M4C. Tighten the tube vice to hold that position.
( 1/8 of an inch = 0.125 thousandths of an inch. The thickness of 2 new nickels is approximately 0.145 thousandths of an inch.)
#5 - To help insure precise movement of the front binding post arm, apply slight finger pressure to the top of the binding post arm. See figs M4A and M5A. With your right hand use hex wrench # 3/32 to tighten the bottom binding screw, fig. M5C, as you tighten the binding screw you will notice the front binding post arm rotating clockwise. This movement increases the distance between the bottom of the armature bar and the top of the coils post. The distance between the coil core and the bottom of the armature bar becomes the machines current stroke length.
As you tighten the bottom binding post screw, watch the needle points closely. When the swivelhead assembly has rotated just enough so that the needle points are inside the end of the tube tip, see fig M5D, tighten the top binding screw fig M5B, until slight contact with machine frame is made, don’t over tighten.

***Power Supply Update PDF ***

#6 - Hook up your power source to the machine, and set the voltage output to approximately 18 volts. Don’t worry if you don’t know the actual voltage setting, it’s okay, but you do need a power supply rated at 24 volts. Hook your power to the machine and set the power to approximately 3/4 max power. ***Power Supply Update PDF***

The next step. Step #7 is the hardest part of machine tuning to learn and to describe, but in reality is quite simple. Creating a complete harmonic balance includes your personal input, ie; hand speed, skin stretch preference, desired technical effects, needle size etc. And therefore, the perfect tune-up (harmonic balance) is a physical position of the point screw, but actually a personal choice of the sound and feel of the machine at the time of the tune-up. Once you understand this procedure you can easily adjust more than one machine to have exactly the same stroke length, but each one having slightly different needle force for different effects.
When you are using a K model machine or our Superflat needles for the first few times, you may have to tattoo a little then retune the stroke length and/or the point gap a few times before you find the sweet-spot that works best for the technical effects you’re applying.
If you’re not already familiar with using a adjustable stroke machine or large groups of needles, you will need to experiment a little to figure out the different possibilities, and how the machine and the working needles should feel in your hand when tattooing. (After reading this description, if you need more help understanding what the machine should sound and feel like, call our Tech-support, we’ll be happy to help.)

(Within 40-50 hours of tattooing with SM ART Tattools, you should have a good feel for your
K model machine and Superflat needles. That should also be enough time for you to see the difference in healing time and results, and the final artistic results of a few tattoos. To understand how to tune your machine for all of the effects that are now possible will take a few more hours of tattooing, but you’ll start understanding and get a good taste of your new potential within a few of hours of using these state of the art tattools.)

When you want to change the stroke or point gap setting(s) of an already well tuned machine, set the stroke first, then set or reset the point gap.You’ll need to find the “harmonic balance” for the new setting by making very slight changes to the point screw. While the machine is running turn the point screw very slow, (one way or the other) less than a quarter of a turn, the machine will run stronger or softer, depending on the technique you’re trying to do. In other words the needles will penetrate the skin under slightly different force or timing when a very small change of the point screw is made. It doesn’t take much of a change of the point screw on an already well tuned machine to make a good or bad difference in the operation of the machine, and or, the impact of the needles going into the skin.
With a trained ear you can hear when the springs come into balance, with a trained eye you can see it. Depending on the stroke length and the front spring tension and technical effects being applied, there maybe more than one point screw position that creates an acceptable harmonic balance. The longer the stroke, and or, the softer the spring tension, the easier it is to see and hear the different harmonic balance position(s) as you come to them while turning the point screw. The first balance point you come to after the points first connect will produce the softest “hit” of the needles to the skin. This is the one I’m talking about. When using superflat needle groups, this is the best position to use. You may also find that round needle groups work very well at this setting. I’ll describe other harmonic balance points in a couple of minutes. A little reminder; Anytime you reset the point screw or stroke length, you’ll need to adjust the tube tip to fit the needle points new position.

Recap step #6, then move to step 7

#7 - Step on the gas and tighten the point screw until it touches the contact point on the front spring. As soon as the points come into contact, the machine will begin running and the sound coming from the open and closing of the points will be very smooth. Tighten the point screw a little at a time. Around 1/4 turn of the point screw from first touch of the contact points, you will find the first harmonic balance position. Because there are so many variables, it is hard to pin-point the exact position that’s best for the machine being tuned. But this is where you start looking and listening for a slight change in the sound coming from the open and closing of the points.
In order to see the change take place, hold the machine on its side, armature bar side up and tilt the machine so you can see the prevailing light reflect off of the moving arm-bar and front spring. With the machine running, loosen the point screw until the machine almost stops running, and then slowly tighten the screw until the sound, coming form the points, change from an even hum to a slight clatter. At this point you’ll notice the arm-bar begins to bounce a little.
As you slowly tighten the point screw the sound and movement of the arm-bar will eventually become very rough and uneven, at that point or right after that you will hear the arm-bar begin to hit the coil post, but not every stroke. Don’t tighten the screw any further.
Now loosen the screw, very slowly until you no longer hear the arm-bar touching the coil post. Continue loosening the screw very slowly until the spring bounce almost stops and the motion and sound become quite smooth. If you watch the front spring, at that very moment, you’ll see and hear both the sound and the movement of the spring become very smooth.Tighten the jam screw to hold the point screw in that position. You have found the sweet-spot and brought the motion of the arm-bar to a harmonic balance. At this time you may notice an occasional, very slight bounce in the arm-bar. This is normal and to be expected.
Even when you find the sweet-spot, the sound the contact points are making as they open and close produces a stuttering, or an out of time sound. You’ll also notice the arm-bar will be bouncing, seemingly out of time. This is normal and actually a good sign the tune-up is accurate and almost complete.
Slightly touch the moving needle bar with your finger to simulate skin tension. With the slightest touch, the “bounce” of the arm-bar assembly will subside and the stuttering, or out of time sound will cease, and the sound and operation now becomes smooth and consistent. If the machine stutters to much, tighten the point a little bit. If it takes more than 1/4 turn of the screw to get the best balance, you may need to lengthen the stroke length a few thousandths of an inch. (any time you tighten the point screw you shorten the stroke length. Eventually you’ll need to readjust the stroke length to keep the balance and the machines high end performance)
The sound and needle force you should be paying attention to is the sound the machine makes, and the force needed to push the needles into the skin. Or, the sound of the machine and the force needed, when you simulate skin tension by touching the needle bar while the machine is running. The sound the machine makes while the needles are not under load is not the sound to judge your machine by.
( Because of the sound the spring bounce makes is so deceiving. Somebody in the recent past (less than 10 years) put an O-ring around the front spring and arm-bar and restricted the bounce of the arm-bar. This made the machine sound faster and smoother while the needles are out of the skin. But in reality, what actually happens is, the needles hit the skin harder and faster than necessary. This causes the tattooer to increase hand speed, which actually diminishes detail, and limits your style of tattooing to the most basic of designs and techniques. The sound of a fast acting short stroked machine is

actually more deceiving than the sound of bouncing springs, in the sense that you really can’t do as much with a fast acting machine set-up, as you can with a properly tuned machine. I recommend you leave the O-rings alone and learn to appreciate the spring bounce.)

You may need to loosen and tighten the point screw a few times to get the real feel of things, but once you see and feel the (sweet-spot) harmonic balance happen, you’ll be able to repeat the adjustment anytime.
Regardless of actual stroke length, any time you need to make a stroke or point screw adjustment, just follow the above directions, it really isn’t hard to see when the machine has become as “balanced” as is possible with that stroke length, spring tension, arm-bar assembly (including needles), and the magnetic force. Tuning the machine to this harmonic balance point will allow the machine to run very smooth when the needles are in the skin. The sound of the machine when the needles are in the skin is the sound that really matters.
#8 - Once you have adjusted the point screw to give you the best performance, you will notice that the needle points are protruding slightly from the tube tip. (If there is more than approximately 0.020 thousandths of an inch of needle point exposed, you may have over-tightened the point screw. One revolution of an 8 x 32 point screw is 0.032 thousandths of an inch.)
Do not adjust the tube length. You should loosen the top binding screw a half turn, then tighten the bottom binding screw until the needle point retracts back into the tube tip. This final adjustment will re-establish the stroke length to the length you originally set in step
number #4.
Tighten the top binding screw, but don’t over tighten. Fine tune the point screw to the first harmonic balance point one more time. The tune-up is now complete.
Most often one adjustment process will be sufficient, but you may need or want to adjust the stroke length and fine tune the point screw a few times. In fact I recommend you experiment. Run the machine for a while with a short stroke and then change to a longer stroke. After a few tune-ups, you’ll be able to make the machine run the way you want, and the way that gives you the results you want. ( Here’s a little hint; With a machine tuned this way, the hit of the needles to the skin is much softer than you are probably used to feeling. Continue tattooing the area until the skin is saturated to the degree you want it to be. The feel of the machine is not as important as the results.)
The machine is now properly tuned, but the main spring still needs to be broke-in. I recommend letting the machine run about 12 hours at low power and then retuned. Any time a new spring is installed on the machine, a break-in period is recommended. After the break-in period the machine will be easier to tune and run a much better. Although this is all there is to tuning a tattoo machine, there is much more to a machine than mentioned so far.

Setting the proper power.
My experience has shown me that most tattooers make adjustments to the voltage and spring tension in excessive amounts. These adjustments usually - over shoot - the sweet spot they’re looking for, and cause other problems the tattooer doesn’t have the experience to recognize. The key to controlling your needle points, is to control and make changes to the machine settings in small predictable and controllable amounts. By following these steps, with a properly tuned machine, your needle should be penetrating into the Dermis to the depth of 0.020 to 0.040 of an inch.

Hook the machine to the power supply and step on the gas, turn up the voltage enough to make the machine run, slowly increase the voltage until the armature bar begins hitting the coil post occasionally, but not every stroke. Your power setting will be approximately 18 volts.

At this point, if the armature bar is hitting the coils post every stroke you probably have to much power, or the stroke length is too short. It is important to note however, that when you’ve been tattooing for a little while, the machine will heat up, which increases electrical resistance in the machine. This resistance, and or, a change in skin texture or technique may require more voltage to keep the machine preforming as it did early in the setting, when the machine was cool and the techniques gentle.
This increase in power may cause the arm-bar to contact the coil post every stroke when the needles are not in the skin. Which is fine a long as the arm-bar doesn't hit the coil post when the needles are in the skin. The range of power (voltage) that can be applied to the machine during the course of a tattoo can sometimes be several volts. As long as you keep the needles from over powering the skin, you can work with any volt setting that keeps the machine running, within the proper power to the needle to the skin ratio.
18 volts should be enough power to start tattooing. If this power setting isn’t strong enough to push the needle points to the proper depth in the skin, turn up the voltage 1 or 2 tenths of a volt at a time until it is enough, but no more. If the power becomes too much, turn the voltage down 1 or 2 tenths of a volt at a time, until you get the right power setting for the technique you want to apply. If your power supply doesn’t have a readout, don’t worry. Turning up the voltage a little at a time until the armature just begins touching the coil post, but not every stroke, is a good start. When you then turn the potentiometer on the power supply enough that you can tell it has moved the smallest amount possible, you have made a change in the voltage. This very small change may be just enough. With a properly tuned machine it doesn’t take much of a change in power to make a significant change in the way the needles hit the skin.
Remember; When the needles are almost hitting the right depth in the skin, but not
quite, the needed adjustment to the perfect needle point depth maybe only one or two skin cells different. This is why it takes only a very small change in voltage to make a significant difference in the way the skin cells take the pigment. See page 61 fig.P1, for another description of depth of penetration.
Ultimately the exact voltage doesn’t really matter, what does matter is that you change the power in small increments, use only enough power to get the job done, but use all the power it takes to get the intended results with the least amount of passes of the needle. Try to get the most from each stroke of the needle.
16 -19 volts may or may not be enough power to do the job with your actual length of stroke, but 18 volts should be about right. Although 20 or more volts is not uncommon for some skin conditions and/or techniques being applied (especially when the machine is warm from being run for a while.
If you feel you need to rush your hand speed to prevent overdose spots, turn down the power a little. If you feel yourself “pushing” the needles into the skin to get the pigment to stay, you need to turn up the power or lengthen the stroke, or both, just a little. A properly tuned and powered machine should do all of the work, you just need to drive.

This next section isn’t the most technical advice I have mentioned, but may be the most important information in this catalog.
The sound of a properly tuned machine is very deceiving. With the machine running in your hand but not tattooing, the sound will be a little rough. You’ll be noticing a kind of stutter, or an occasional out of step sound.

What you’re hearing is the bounce in the springs. Don’t let this stuttering sound bother you, it is normal and a good sign that your machine is running strong enough to tattoo and soft enough to respond to the skins tension. (if you have a fixed spring machine that has an O-ring, you won’t hear this stuttering I’m talking about).
The sound you should be paying attention to is the sound of the machine when the
needles are buried in the skin to the tube tip. If your machine is set like the one described above, your machine will sound very smooth and constant. If the armature bar hits the coils post when the needles are in the skin, you definitely have too much power going to the machine for that stroke length. If the needle force is right, but you can still hear the arm-bar hit the coil post every stroke, the best thing to do is to lengthen the stroke just enough that the arm-bar stops hitting the coil post when the needles are in the skin.

When you are tattooing, you will notice a stutter in the sound of the machine when the needles exit, and while they’re out of the skin. This stutter doesn't effect the performance of the machine or the effects of the needles while they’re in the skin at all. It is perfectly normal. At this particular point the stuttering you hear is an indication that you are letting the skin influence the tattooing process.
(And again, if your machine has an O-ring, it is probably running to hard and the machine won’t have the stuttering I’m talking about)

The best indicator that your machine is tuned and running properly is when the spring bounce subsides when the needles are in the skin. When this happens you have established a harmonic balance between the machine, the medium and you as the artist. When your machine responds to the art medium (skin) like this, you can tattoo with any size of needle group, and expect great results. If your machine has never run like this, that’s too bad, you’ve been missing a lot. Just tune your machine like I’ve described, and enjoy the rest of your tattoo career working with state of the art tattools and techniques.

Here are a few other pointers to help you understand some other options.
Our spring theory says spring tension only needs to be strong enough to pull the needles from the skin. A well conditioned spring is not worn out until it is broken. Soft springs help create soft shading, smooth solid color and sharp detail.
The stronger the springs tension is, the faster your hand speed naturally increases. High hand speed diminishes detail, limits your artistic potential and creates other problems. Generally speaking, the softer the spring tension, the slower the hand speed can be, and smoother the shading effects can be. Soft spring tension and long stroke increases the time that can be spent on the detail. Without having to rush your hand movement less damage is done to the skin, which also contributes to quicker healing and brighter colors.
If you’re shading detail, use the largest needle group you can comfortably get into the areas being tattooed. Use slow hand speed and go over the area many times until solid color appears. Just look for the even texture of skin, as the skin becomes saturated with pigment, the texture will appear similar to brushed velvet. When both saturation and texture become solid and smooth, move on. If holidays appear too late to work-over on that setting, or for other technical effects, you can let the tattoo heal, and go over the area again to apply the same or different color There is nothing wrong with leaving intensional holidays. I call areas intensionally left as a holiday, Vacations.

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