On Wednesday 03 June 2020 14:54:31 Chris Albertson wrote: > You problem finding a setting in Cura might be that Cura is not > showing it to you. By default you get a very "dumbed down" list of > settings. But look undr "prefferences --> Settings" and there is a > long list of setting and checkboxes. If you check the box Cura will > show you the setting. Most of these you wil never touch but some are > "must haves". > > You absolutely ned to be able to control the wall thickness and the > skin thickness. > You likey want to be able to control the kind of infill, lines, > triangles or Gyroid. I use the latter mustly > The pulley teeth are very low density, mostly air with a filament bridge at a 45 degree angle. How do solidify the teeth? What I'm getting would cut up an XL belt in an hours work, its that sharp.
> I run an informal strength testing program when printing racing > quadcopter bodies I intentionally broke some parts. Here is a rule: > Strenght is mostly in the skin but you need enough in-fill so the > skin does not deform when the part bends. In PLA deformation equals > breaking. PLA is like building with glass. Use large tubes filled > with air and it will be strong like a coke bottle. Thin sheets are > weak like window glass. The coke bottle does not get its strength > from the air inside the bottle but by its shape. Use PLA as it it > were glass, not as if it were aluminum. > > Given the above the best PLA designs are "puffy" and thick. Doing > this with aluminum would be expensive but PLA is filled with 20 to 30 > percent density foam inside. With PLA parts the cost is mostly in > the surface areas, not so much the volume. > > Also like the coke bottle make every surfave curved and non-flat. The > compound curves are strong. Like the hood of a car is stong only > after the sheet metal is stamped into a compound curve. > > It takes a while to get your brain around the fact that PLA is not > metal or wood and very complex shapes cost nothing. At first we > design stuff as it if were machined but we can do better. > > One thing I want to learn is to use "generative design" tools. This > is basically a shape optimizer an will re-design parts based on the > loads and other constraints. The software comes up with shapes no > human would ever think of but turn out stronger and lighter. > https://www.autodesk.com/solutions/generative-design > > On Wed, Jun 3, 2020 at 3:13 AM andy pugh <bodge...@gmail.com> wrote: > > On Wed, 3 Jun 2020 at 07:27, Gene Heskett <ghesk...@shentel.net> wrote: > > > 50% fill makes very strong parts, but 20% fill is strong > > > > > > > too. I usually use 20% or 25% infill. If I want stronger parts > > > > I'll increase the number of outer layers. > > > > > > I'll have to ask how you do that with cura? > > > > Presuming that the part has been placed on the bed in Cura. > > Then in the bar at the top, where is lists the printer, the extruder > > / material and the quality, click the quality section, and you will > > seee a drop-down of all the settings. > > > > Then in the "Shell" section you can choose how thick you want the > > wall, and how many lines. > > > > I think that if your printer can print at 100% then it is probably > > under-extruding. There should be only barely space for 100% fill, > > and so you would expect cumulative oozing errors to build up. > > > > I typically print at no more than 25% fill, and for foundry patterns > > I am down at 5% to save time. > > > > -- > > atp > > "A motorcycle is a bicycle with a pandemonium attachment and is > > designed for the especial use of mechanical geniuses, daredevils and > > lunatics." — George Fitch, Atlanta Constitution Newspaper, 1912 > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
