The frame is one of the most important parts of the machine. If the frame geometry is out of whack your machine will never run correctly. The above picture is of a decent tattoo machine frame with solid frame geometry.
This is the spring deck or, “saddle.” Notice how this deck is slightly ramped to effect the rear spring tension/stroke. You will see both ramped, flat decks, and decks that can be adjusted. Decks are set up this way with specific machine functions in mind. Note: A flat deck will add zero tension/stroke to the spring assembly; while a ramp will give it some extra tension and change the stroke a little. You want to look at the contact post and spring deck when building a machine for a task you have in mind. (If you need to know what a spring is click here.) (I’ll cover stroke in another article later.)
If the deck is not aligned with the coil heads, tube vice, or/and front binding post. Then it is garbage. This is true for every part. They must all line up. You must start with proper frame geometry or you will never build a machine that will function correctly. That’s what, “frame geometry” is.
The pictured frame above is not made from a magnetic material so it will need a yoke to function properly. (Short article on what a yoke is.)
Notice that this machine doesn’t need a yoke under the coils. That is because the iron frame acts as a yoke. Also, this machine has a flat spring deck when compared to the first machine frame. Iron is a good solid work horse material, but it is heavy. Iron also is more desirable than steel, as it has double the magnetic capacity and will not retain a residual magnetic field as bad as steel does.
If you look at different machines you’ll notice that the front binding post will be set more towards the tube vice, (A little past the front coil and higher up for a longer stroke.) Or back toward the spring deck, (More lined up with the front coil and lowered for a shorter stroke.)
This is because the position of the front post will help determine whether your machine frame would be better set as a shader or a liner. In the picture above the adjustable frame is set to a shading/color position. If you were to push the contact screw back over the front coil it would be a lining position. Of course you can get a machine designed to run as a shader to function as a liner; or a liner frame to shade; but it’s just easier to start off with a frame that was made for what you want to use it for. It’s also why adjustable sliding front posts are a nice feature.
In short: The front post position will effect the, “throw” of your machine. You must pair this with the springs you use, coils/cap, spring tension, and contact gap.
So how do you determine a good frame from a shitty one? Or the noob question, “What is a good tattoo machine to buy?”
Why is it a POS? It’s all dependent on the process used to create the frame. This frame was made by cutting sheet metal and bending it into shape by automated machines. If you look closely you can see how warped this frame is. The frame geometry on these frames will always be warped; making them worthless. Don’t go anywhere near these thin stamped POS frames.
This machine looks solid, but it is in fact a POS. It is made by drilling and bolting three cut pieces together. It isn’t noticeable in the picture, but everything on this machine is out of alignment. The holes are slightly off and the whole thing was carelessly bolted together. You’re going to have unscrew the bolts and get everything into alignment again, then tighten things down; hoping you got it right. Running the machine will vibrate the bolts and cause them to loosen over time. You can see where this is going…
When looking for a frame, start out by looking for a cast frame with a simple practical design. Cast frames carry some of the most desirable qualities. The only decision you have to make is what kind of material the cast frame will be made from. You have different deciding factors when choosing your frame.
EDM wire cut frames can also be good frames. If you’re buying your frame from a Chinese source it’s most likely going to be an EDM wire cut frame. Look for something with clean angles and a solid thickness. You will have a hard time telling a EDMWC frame from a cast frame. So beware of sellers claiming it’s a hand crafted cast frame.
The lighter the better. Having the lightest machine possible helps reduce hand strain. Although many people prefer a heavy frame, claiming that the weight absorbs the kinetic vibrations and steadies the line work. Get some machines in your hands and feel them after a needle and tube are loaded. Can you hold that machine for say, 2 hours?
A good shape is something well thought out for the machines intended use. Bull dogs, dials, and J frames are solid designs. Anything that has good solid cast construction and straight forward geometric angles. The design will also affect the weight; so go for the most minimalistic designs.
Over time steel frames will become magnetized. This can cause funky things to happen as the interfering fields can throw off the operation of the machine. This includes any metal that reacts to a magnetic field. It is also one reason why brass/copper is a commonly desired metal in frame construction. Steel is prone to much more Residual magnetism than iron. This is one reason why an iron armature bar and iron coil cores are so desirable. The magnetic field in iron reduces to zero more effectively than steel.
Durability of a material is common knowledge. Look out for materials that will rust or bend easily. One of the issues with machines made from non air craft aluminum.
Brass, iron, steel, copper, and aluminum are really the only materials you want to tinker with. It’s up to you to figure out what traits you want your machine build to have. I’ve seen really bad ideas like wood frames. I don’t think that porous wood with tons of places for bacteria and BBPs to hide should ever be used in a machine. Plus it will vibrate with the wood grain like crazy.
If you want a good quality machine out of the box for very little money I recommend these guys: https://www.internationaltattoosupply.com/
Of course you’re going to have to strip your machine down and set it up to run exactly how you want it to after it arrives. But the frame and all the parts are an incredible deal for the kind of quality they carry in their construction.
Note: I use a lot of pictures of generic machines because I don’t want to piss off the brand name guys. And remember the first thing you should think of when selecting/building parts is can this be sterilized?
NOTE: Yes you can build/find frames that are welded, bolted, etc… that will have excellent frame geometry. Casting is a solid piece that has little room for error when you are buying parts for construction. That’s why it comes out as the top choice.
Here’s a video from Underground Demagraphix that explains some things a bit more in depth: