About 3D Printer
Previously, 3D printer was a topic as dream technology that may change the world.But now the fever has been cooled down. Because, many people realize that it's a illusion making everything, I think. Many people think 3D printer can make everything. Actually it chooses parts that it can make. There are available parts and unavailable ones. And you may think it can make parts rapidly. It needs many time for doing. The surface of printed parts is not smooth. It is very rough. You have to polish it in many time by your hands. But other methods have another restrictions as well. It's no problem if you know good points and weak points. In addition, the noize is important issue. If you cut alminum plates by electric thread saw and bend it by hummer, it's very noizy. 3D printer is quieter.
What's the difficult model for 3D printer?
General 3D printer is Fused Deposition Modeling FDM method. Heated resin is discharged from a nozzle and deposited.
Could you image building a bridge piling up bricks? It's necessary to support between the bridge girder and the bridge girder. If you want to build a bridge, you must make an arch or place a support.
It's same on 3D printing. The support of 3D printing is removed by hands. The material PLA is hard. You have to shave with a file.
The size of general nozzle is 0.4mm. The depositing pitch of cheap 3D printer is approximately 0.1mm. 3D printer cannot model small shapes. And it cannot make thin shapes as well.
In case of printing a model that height is larger than the area of the bottom or the area of the bottom is large and thin parts ,the model warps. The raft is a countermeasure. It is removed by hands.
It's important to understand the 3D printers characteristics. And the design the shape that doesn't need to add any supports and rafts is good design.