{"action":"created","issue":{"url":"https://api.github.com/repos/daid/Cura/issues/771","labels_url":"https://api.github.com/repos/daid/Cura/issues/771/labels{/name}","comments_url":"https://api.github.com/repos/daid/Cura/issues/771/comments","events_url":"https://api.github.com/repos/daid/Cura/issues/771/events","html_url":"https://github.com/daid/Cura/issues/771","id":28942106,"number":771,"title":"Holes on top surface (pillowing)","user":{"login":"luotinen","id":6695329,"avatar_url":"https://avatars.githubusercontent.com/u/6695329?v=3","gravatar_id":"","url":"https://api.github.com/users/luotinen","html_url":"https://github.com/luotinen","followers_url":"https://api.github.com/users/luotinen/followers","following_url":"https://api.github.com/users/luotinen/following{/other_user}","gists_url":"https://api.github.com/users/luotinen/gists{/gist_id}","starred_url":"https://api.github.com/users/luotinen/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/luotinen/subscriptions","organizations_url":"https://api.github.com/users/luotinen/orgs","repos_url":"https://api.github.com/users/luotinen/repos","events_url":"https://api.github.com/users/luotinen/events{/privacy}","received_events_url":"https://api.github.com/users/luotinen/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/daid/Cura/labels/Bug","name":"Bug","color":"e10c02"},{"url":"https://api.github.com/repos/daid/Cura/labels/SlicingEngine","name":"SlicingEngine","color":"fbca04"}],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":31,"created_at":"2014-03-07T07:04:26Z","updated_at":"2015-06-10T21:43:54Z","closed_at":null,"body":"On default settings Cura makes pretty sparse infill. On topmost layers the bridging of these large gaps is difficult. Observing the process the following appears to happen: part of the material sticks to the edges of the holes and forms cantilevers. Due to fan cooling the top and heat radiating, conducting and convecting from below part, the cantilevers bend upwards. After a few passes they act as wipers and result in gaping holes in the model or weakened and thinned centers of the holes.\r\n\r\nIn other software, the bottom and top infill can be set separately and the problem may be avoided in the slicer. The hardware solution is a stronger fan. For Cura I have some suggestions:\r\n- enable infill settings for top and bottom regions\r\n- automatic pillowing prevention (automatically start making more denser infill when approacing top layers and set fan on high)\r\n- enable fan boost for top layers\r\n- warn users about the consequences of using sparse infill\r\n\r\n![wp_20140306_004](https://f.cloud.github.com/assets/6695329/2354643/9d88830a-a5c6-11e3-9064-a6f752c21d5e.jpg)\r\nPillowing in top column (worse) and bottom flat regions (uneven quality) using default settings and layer height of 100 um.\r\n"},"comment":{"url":"https://api.github.com/repos/daid/Cura/issues/comments/110923163","html_url":"https://github.com/daid/Cura/issues/771#issuecomment-110923163","issue_url":"https://api.github.com/repos/daid/Cura/issues/771","id":110923163,"user":{"login":"nophead","id":566149,"avatar_url":"https://avatars.githubusercontent.com/u/566149?v=3","gravatar_id":"","url":"https://api.github.com/users/nophead","html_url":"https://github.com/nophead","followers_url":"https://api.github.com/users/nophead/followers","following_url":"https://api.github.com/users/nophead/following{/other_user}","gists_url":"https://api.github.com/users/nophead/gists{/gist_id}","starred_url":"https://api.github.com/users/nophead/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/nophead/subscriptions","organizations_url":"https://api.github.com/users/nophead/orgs","repos_url":"https://api.github.com/users/nophead/repos","events_url":"https://api.github.com/users/nophead/events{/privacy}","received_events_url":"https://api.github.com/users/nophead/received_events","type":"User","site_admin":false},"created_at":"2015-06-10T21:43:54Z","updated_at":"2015-06-10T21:43:54Z","body":"Print thicker layers or wider tracks so that the filament doesn't snap when\nit tries to bridge the gaps. I.e. keep the filament cross sectional area at\nleast half the nozzle area.\n\nOn 10 June 2015 at 22:35, M. Vondano <notifications@github.com> wrote:\n\n> Just my two cents: When I did my first 3d prints I encountered the 'wart\n> problem' quite often. I elminated it by reducing speed and print\n> temperature. If I look at it now, I don't think that the bridges (alone)\n> were the problem, but the junctions of the infill (were there is twice as\n> much material each layer). I think whenever I had warts during prints the\n> printhead came too close to the surface (at these junctions) or even\n> scratched it on higher prints which caused them to bend up and prevent a\n> good bridging.\n>\n> —\n> Reply to this email directly or view it on GitHub\n> <https://github.com/daid/Cura/issues/771#issuecomment-110921613>.\n>\n"}}