From: fredj@wang.com (Fast Freddie)
Newsgroups: rec.arts.bodyart
Subject: Re: tat gun question
Date: 21 Jul 92 21:32:17 GMT
Organization: Wang Labs, Lowell MA, USA

"Alan S. Ferrency" <af1x+@andrew.cmu.edu> writes:

>Hello.
>Can anyone explain specifically how a tattoo gun works, or how it's constructed?

It is a basic dorbell circut.  The voltage is usually between 6 and 14Volts
it goes through 2 coils (electromagnets) when the coils "energise" they
pull an armature bar.  The armature bar has a contact spring and the needle
bar attached to it.  The contact spring is a switch that enables the coils
to energise (one side of the coils circut is connected through the contact
points).  When the coils pull down the armature bar this breaks/opens the
circut (if the machine is set up correctly :-) ).  When the circut opens
the coils "relax" which causes the spring to "spring" the contact points
back together, closing the circut starting the process over again.  All the
mean while the needle bar is riding up and down in the tube as the armature
bar is going up and down.

>I haven't seen one close up (like, I can inspect it closely and turn it around
>in my hands), but it seems to have two solenoid/relay type things on it which
>make the needle move in and out.  I couldn't tell if they were solenoids or
>relays though.  Does the needle move out at the rate of the AC current (like,
>60Hz here or 50Hz in parts of Europe) or what?

The current is DC.  The speed is a factor of th number of windings and the
ammount of iron in the coils.  The mass of the armature bar, and needle
bar.  And the combination of the point gap and voltage.  Most modern
machines have a capacitor across the ciols and points so the points dont
spark much.  If the points spark they get pitted and have a carbon buildup
which significantly raises the resistance of the circut requiring more
voltage to sustain vibration (Sounds erotic almost :-) ).


>Also, I haven't seen needles close up either.  I understand they have 1, 3, 5,
>or however many needles, in a row, kind of like a comb, to make a wide line.
>What keeps this line of needles from acting like a calligraphy pen- so the line
>doesn't change width depending on which direction you're "drawing" in?

There are usually two categories of needles: liners (for the outline) and
shaders.  Liners are usually in a round configuration of 1 3 5 & 7 needles.
There might be more but i just haven't been exposed to them.
The shaders are usually in a line from 4 needles to 9 needles, although 4 &
6 seem to be popular.  There is also a 14 needle round shader, i think for
bigger areas.

The machines are also set up to be either a liner or shader.  The gap
between the points being the difference.  The thickness of a nickle for a
liner and a dime for a shader (i think).

That's why there seems to be more sensation when you get the outline done
as opposed to the shading.  Karl any comments regarding this??

When shading the machine is moved in a circular pattern (Usually).
Sometimes the angle varies as well around 45 degrees.  Though i've seen
more like 100 with some artists.

>Thank you very much for the info...
You're welcome
Fred Jewell
Fast Freddie
Newsgroups: rec.arts.bodyart