10.C - Maintain Impact, Thermal, and 3DPrinters Flashcards
Describe an impact printer.
An impact printer strikes an inked ribbon against paper to leave marks.
List types of Paper used with impact printers.
Plain paper
Carbon paper (or impact paper) is used to make multiple copies of a document in the same pass (hence carbon copy, or “cc”).
Tractor-fed paper is fitted with removable, perforated side strips. The holes in these strips are secured over studded rollers at each end of the platen.
What are the two types of feeder mechanisms?
Tractor fed - continuous-roll paper with matching holes in the edges fits over the pins. The wheels turn and pull the paper through the printer.
Friction feed - uses two rollers placed one on top of the other. The rollers turn to force individual cut sheets of paper or envelopes through the paper path.
Describe impact printer ribbons.
They can be made as a complete loop moving in one direction only. The two-spool design requires a sensor and reversing mechanism to change the direction of the ribbon when it reaches the end.
Describe the printing process of an impact printer.
In a dot matrix printer, a moving carriage that contains pins sweep across the paper. The pins are fired by coils of wire called solenoids.
When a coil is energized, it forms a strong electromagnet that causes the metal firing pin to move sharply forwards, striking the ink-bearing ribbon against the paper.
A strong permanent magnet moves the pins back into their resting position immediately after firing.
What’s the purpose of a platen gap lever?
It adjusts the gap between the print head and the platen to accommodate different thickness of paper.
Higher end impact printers do this automatically
What are some maintenance guide lines for Impact printers?
Review the documentation for your specific impact printer model for information on the recommended maintenance tasks. lol
Describe 3 types of thermal printers?
Dye sublimation - used for photo quality output
Thermal wax transfer - used as an alternative to color laser
Direct thermal - used for high volume receipt printing
Term to determine print speed of thermal printers
Inches per Second
Typical Dots per Inch of a thermal printer
200 -300 dpi
Describe three components of a thermal printer
Thermal paper that contains chemicals designed to react and change color as it is heated
Heating element within the printer to create images.
Feed assembly, paper is friction-fed through the print mechanism by a stepper motor turning a rubber-coated roller.
Describe the printing process of a thermal printer.
Direct thermal printers have a heating element with heated pins that create an image directly onto special thermal paper.
Describe the 3D printing process.
The 3D printer imaging process begins with either a scan created by a 3D scanner or by creating an object using 3D modeling software.
From either of these methods, you end up with a 3D model created in software and saved to a 3D model format. This model is then sliced with slicing software into horizontal layers. The slicing software might be contained in the 3D modeling software or within the 3D printer.
The result is a print job specifying how each layer in the finished object is to be deposited.
The sliced model is then fed to the 3D printer over a USB or Wi-Fi connection, or by inserting an SD card containing the file into the printer.
The printer then melts the filament and extrudes it onto the build surface, creating layer upon layer based on the slices. The extruder (and sometimes the build bed) is moved as needed on X/Y/Z axes to create the build.
Describe components of Fused Filament Fabrication (FFF)
Print bed/build plate—a flat glass plate onto which the material is extruded. The bed is usually heated to prevent the material from warping. The bed must be leveled for each print job—this is usually automated,
Bed/build surface—a sheet placed onto the base plate to hold the object in position while printing, but also allow its removal on completion. The bed surface material may need to be matched to the filament material for best results
Extruder—the equivalent of a print head in an inkjet. A motor in the extruder draws filament from the “cold end” through to the nozzle (or “hot end”), where it is melted and squirted onto the object. Different size nozzles can be fitted to the extruder.
Gears/motors/motion control—enable precise positioning of the extruder.
Fan—cools the melted plastic where necessary to shape the object correctly.
What are two popular plastics use for filaments?
Polylactic Acid (PLA)
AcrylonitrileButadiene Styrene (ABS)
