Changes

Jump to navigation Jump to search
m
Line 104: Line 104:  
#Surface: The surface finish of a part is a rather complex subject. In 3D printing, and for typical applications of 3D printed parts, it mostly refers to the mean (statistical) difference between the height of cusps and valleys on a part and their deviation from that mean, at a macroscopic level. The most important consideration is that when 3D printing, most surface finishes are quite rough (deviate significantly from the mean), and thus are sanded down considerably to knock out the cusps left by the printer. This post processing can negatively affect the form of the final part.
 
#Surface: The surface finish of a part is a rather complex subject. In 3D printing, and for typical applications of 3D printed parts, it mostly refers to the mean (statistical) difference between the height of cusps and valleys on a part and their deviation from that mean, at a macroscopic level. The most important consideration is that when 3D printing, most surface finishes are quite rough (deviate significantly from the mean), and thus are sanded down considerably to knock out the cusps left by the printer. This post processing can negatively affect the form of the final part.
 
Note that ''<u>a proper mechanical fit between components demands a good tolerance on form, feature position, and surface finish</u>'', such that it is typically impossible to obtain a proper fit when 3D printing, and that if you are considering the 3D printing of critically interfacing components, 3D printing should not be used unless post processing <u>''is built into the design''</u>. For mechanical designs, you will notice that a main application is brackets. This is because brackets only need good positional tolerance on holes and mating faces, which 3D printing can almost always provide (the tolerance on form for holes is not that important since they are typically clearance holes). However, since some brackets are easily laser cut, 3D printing brackets is only done under certain specific conditions. It certainly has shown its commercial use in cost cutting by replacing intricate multi-part assemblies by ''generatively designed'' (we'll say computer generated for now) parts, as shown in the picture below.
 
Note that ''<u>a proper mechanical fit between components demands a good tolerance on form, feature position, and surface finish</u>'', such that it is typically impossible to obtain a proper fit when 3D printing, and that if you are considering the 3D printing of critically interfacing components, 3D printing should not be used unless post processing <u>''is built into the design''</u>. For mechanical designs, you will notice that a main application is brackets. This is because brackets only need good positional tolerance on holes and mating faces, which 3D printing can almost always provide (the tolerance on form for holes is not that important since they are typically clearance holes). However, since some brackets are easily laser cut, 3D printing brackets is only done under certain specific conditions. It certainly has shown its commercial use in cost cutting by replacing intricate multi-part assemblies by ''generatively designed'' (we'll say computer generated for now) parts, as shown in the picture below.
[[File:Poor-surface-above-supports.jpg|alt=Poor surface finish over supports|thumb|Picture showing the surface likely obtained over supports. As can be seen, the finish is extremely coarse.<ref>Simplify3D (2022). Poor Surface Above Supports. Accessed on 05-05-2022 at https://www.simplify3d.com/support/print-quality-troubleshooting/poor-surface-above-supports/</ref>|left]]
+
[[File:Poor-surface-above-supports.jpg|alt=Poor surface finish over supports|thumb|Picture showing the surface likely obtained over supports. As can be seen, the finish is extremely coarse.<ref>Simplify3D (2022). Poor Surface Above Supports. Accessed on 05-05-2022 at https://www.simplify3d.com/support/print-quality-troubleshooting/poor-surface-above-supports/</ref>]]
 
===Supports===
 
===Supports===
 
As explained in the 3D printing page, supports are sometimes required to support overhanging sections of a print. Due to the downsides of supports discussed below, it is typically better to avoid supports altogether when designing for 3D printing.
 
As explained in the 3D printing page, supports are sometimes required to support overhanging sections of a print. Due to the downsides of supports discussed below, it is typically better to avoid supports altogether when designing for 3D printing.
Line 113: Line 113:  
====Hard to access supports====
 
====Hard to access supports====
 
Support removal should always be an important consideration whenever using them. Unless of course you are fine leaving your supports in your print (in which case you might as well enclose that volume and have it be an infilled volume), you will have to remove your supports at some point, and such, you should have them be easily accessible with at the very least some snub nose pliers. While soluble supports are an option, they are practically never used in our Makerspace for prints unless the surface finish and form of the print over a support is critical. While soluble supports are cool and all, most designs can avoid containing supports that are hard or impossible to reach.
 
Support removal should always be an important consideration whenever using them. Unless of course you are fine leaving your supports in your print (in which case you might as well enclose that volume and have it be an infilled volume), you will have to remove your supports at some point, and such, you should have them be easily accessible with at the very least some snub nose pliers. While soluble supports are an option, they are practically never used in our Makerspace for prints unless the surface finish and form of the print over a support is critical. While soluble supports are cool and all, most designs can avoid containing supports that are hard or impossible to reach.
  −
   
[[File:Big Print Split.svg|thumb|A big print is split to ease printing.|alt=]]
 
[[File:Big Print Split.svg|thumb|A big print is split to ease printing.|alt=]]
 
===Build plate adhesion===
 
===Build plate adhesion===
295

edits

Navigation menu