xxx = Power Supplies and Needle Depth Aaron Williams EP 262 Power_Supplies_and_Needle_Depth__Aaron_Williams__EP_262 Fireside Tattoo Network

Tattoo Science: Power Supplies and Needle Depth Aaron Williams EP 262

Power Supplies and Needle Depth

Aaron Williams | EP 262

It's truly incredible when non-tattooers come together with artists in order to make the tattoo industry better for everyone. Aaron Williams of Tattcom just so happens to be one of those people. Over the past few years Aaron has been researching and developing new products to help tattooers reduce variabilities and be more consistent in their craft.

In this article we dive deep with Jake and Aaron to explore the physics and engineering of tattoos. From contrasting motors, gauging machine performance, to advocating for more research in tattooing. If you enjoyed our conversations about tattoo science, then this episode will be right up your alley! Join them as they try to uncover new insights into an age-old practice!

This episode was made possible thanks to:

Interview By Jake Meeks —

Wiritng By Daniel Pushcarich

Topics: tattoo science, ink in skin, Tattoo Science, Tattoo Physics, Machine Building, Tattoo Machine Power Supplies, Coil Tattoo Machines, Rotary Tattoo Machines, Tattoo Needle Cartridges, High Speed Camera, Tattoo Technology


Picture of highspeed needle depth puncture

Aaron Williams (@tattcom) is 10 year machinist and engineer who has worked in several industries, and is one of the owners of Tattcom, a tattoo technology company. Aaron’s goal with Tattcom is to bridge the gaps in tattooing and modern technological advances to give tattooers freedom and consistency with their equipment. Aaron also aspires to increase the amount of research being done in tattoo technology.

Aaron and Tattcom are based in South Carolina

Please enjoy!



  • Connect with Aaron Williams: | @themadscientist684 | @tattcom |


  • [01:40] A Brief History Of Aaron Williams
  • [04:49] Early Experimentation with Rotary Tattoo Machines
  • [08:37] Tech Progress! In Hardware AND Software
  • [10:04] Why Power Supplies? Transitioning away from Rotaries
  • [12:12] Working Towards Power Consistency in Tattoo machines
  • [13:05] Motormouth, Brushless and Brushed motor comparison
  • [15:26] Insight on “Bog” in Tattoo Machines
  • [19:23] What Makes These Tattoo Machines Feel Different?
  • [25:00] Do More Tattoo Research, Texas Taking the lead
  • [28:20] Just Below the Surface
  • [35:51] High-Speed Tattooing Footage
  • [41:21] Testing, Testing!
  • [44:52] How Do We Apply This to Tattooing?
  • [48:23] Taking the Guesswork out of Tattooing
  • [52:31] Achieving Consistency in Your Tattoo Equipment
  • [58:31] Tattoo Machine Not Just Make Ink go in Skin
  • [01:00:59] Needle Cartridge Catastrophe! Can we work around these issues?
  • [1:05:49] Tattoo Needle Air Draft Phenomenon
  • [1:10:24] Call to Action! What Would You Like to See?


 Insight on “Bog” in Tattoo Machines

“[15:26] So Bog, I would basically define as the speed of the machine slowing down…resistance, load, torque. That resistance of the skin is transmitted through the needle bar up to the cam or mechanism driving it.  And, that in turn is torque or demand on the motor. ”

— Aaron Williams

Let’s Define Some things here. Resistance is the opposition that a substance offers to the flow of electric current. Load is the force exerted on a surface or body. Torque is a measure of the force that can cause an object to rotate about an axis. Torque relates to the rotational force of an electric motor while speed refers to the rate that the motor can rotate.

The needles puncturing the skin creates resistance, causing strain on the components of a tattoo machine, this is called "bog" or "give". That being said, coil tattoo machines produce a particular type of “bog” or “give” that tattoo artists worldwide say is particularly useful for reducing trauma to the skin.

In many pen style machines and Rotary machines the cam needs to complete a full rotation in order to penetrate and exit the skin. There isn’t a lot of “natural” resistance from the pushing back on the needle so in many cases this can be more traumatic or damaging to the skin. Many rotary machine manufacturers add different mechanisms and membranes to attempt to induce this same effect.

What Makes These Tattoo Machines Feel Different?

“[19:23] This all comes down to the machine engineering and design and how efficient the mechanism is that's in there, because there's always going to be losses when you have bearings and other mechanisms put between the motor and the needle”

— Aaron Williams

Usually what determines how hard a rotary hits is the voltage of the motor, but that’s not always the case. In the video above Aaron describes how sometimes the power behind a tattoo machine is just from the engineering or the mechanism the machine is using.

Ink Machines pen style tattoo machine

The more features or points of contact you add between the motor and the needle, the more work or friction is created. Therefore, you have potential loss and a reduction in power.

How Do We Apply This to Tattooing?

“[44:42] if [you prefer] having it just by feel… but then you can put the numbers behind it, you can have a further, better understanding, and the knowledge to exploit these things, and say ‘[man] I want to run my machine at… [or] I’ll do my hand speed at…’ or achieve certain effects. Then, you know exactly what to do with ANY machine to get that effect. It’s not guesswork anymore”

— Aaron Williams

In the article, “Tattoo Hand Speed Calculator”, Aaron Williams writes::

The punctures made by the tattooing needle(s) need to be in perfect harmony with the reciprocation rate of the tattoo machine, as well as in sync with the artist's hand speed. If one of these variables [are] not in sync with the other, the needle punctures can be placed too closely together resulting in overlap which can tear the skin… If the needle punctures are too far apart, then the desired density and saturation is not achieved. 

With the right balance of hand speed and machine speed, one can find the “sweet spot” where the ink seems to be deposited effortlessly into the skin.

whats your hand speed

To obtain optimal saturation when lining, shading or packing color, there is an ideal ratio of hand speed variations and voltage that can be achieved. This "perfect" combination will allow you to achieve maximum impact without fail.

With that said, struggling to identify the "sweet spot" every time you experiment with a new technique can be tiresome. You can use these stats to find an average that works for you in between a range of numbers so that you’re at least getting a more consistent level of saturation. This would reduce the amount of guesswork trying out different voltages and machine setups.

Achieving Consistency in Your Tattoo Equipment

“[52:31] Just like…any problem, you need to identify your variables and any areas that you have control over first. In this formula I’m presenting, you have control over certain things…you could select a different needle size, but at the end of the day that’s outside of your control, and once you select it, it's fixed…”

— Aaron Williams

Tattoo artists and equipment manufacturers are always striving for consistency. To attain this, it is critical to minimize the number of variables in your set-up.

Coil tattoo machines have been a stalwart of modern tattooing since its inception. When properly tuned, they can be the difference between an unforgettable experience and a disaster. Unfortunately, their main issues--uneven weight distribution and daily adjustments--can become problematic for less experienced technicians who may not know how to diagnose problems quickly and efficiently.

The modern rotary pen boasts some impressive improvements, killing two birds with one stone. Not only does its weight balance offer hand fatigue relief and reduced nerve damage from vibrations, but the need for frequent tuning is nonexistent - eliminating many of the possible variables that coils tend to have. No more need to worry about how your machine is feeling that day…

Mo’ Efficiency, Mo Money, Less Problems

“[57:53] If you want to take a ritualistic time to set your coil machines up and do a piece, you could still use them. You can still do all that for sure…but at the end of the day, if you’re trying to run a business, and make money, and improve your efficiencies…having tools that require the least amount of maintenance, and things like that, which is the rotary”

— Aaron Williams

Just like a mechanic loves to work on his old beat-up Pontiac Firebird and get it running again, some tattoo artists love the feeling of tuning up their old worn down machine with a new spring or adjusting the armature bar and getting it to hit “Just right”. It’s a passion that a lot of tattooers share. 

But let's face it; some people prefer simplicity over complexity and just want to start their car without having to tinker around under the hood. There’s nothing wrong with either side of the equation. It’s like the difference between manual and automatic transmission, it just comes down to preference. Some people just like to get in and get to work. 




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