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I have had a 3d printer for a while now, and I have a lot of the quality settings dialed in pretty well, but one thing that constantly bugs me is removing the raft from my finished prints. I am using Repetier and I have set the air gap to 0.2 mm. That led to much better results than the default 0, which were impossible to remove at all, but it is still not great. Are there any settings I should look at changing to get easier to remove rafts? Does the filament affect this? I am printing in Hatchbox PLA at high temps. I have a heated bed, and reducing the temp on that did seem to help. Maybe it keeps the layers on the raft from fusing with the layers on the part? Any help is greatly appreciated. Thanks.

Matthew
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    Not an answer, but: Why do you use a raft at all? Most people don't. – Tom van der Zanden Sep 27 '17 at 22:08
  • I thought that was what everyone did to make sure the print stuck to the bed. I am a newb, there wasn't a whole lot of thought behind it. lol – Matthew Sep 28 '17 at 01:47
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    Probably the raft density is too high. This rafts should be like supports 40 or 50%, I had the same problem when I started to print but I never use this parameter due the part gets sticky on masking tape. – Fernando Baltazar Sep 28 '17 at 05:28
  • @FernandoBaltazar Make an answer? – Tom van der Zanden Sep 28 '17 at 06:10
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    MatthewFegan as TvdZ said - using raft is not so common. Try paper glue or hairspray, personally i use paper glue and it's just incredible, it's also clean (as hairspray spreads itself everywhere) and it's also cheap nad easy to cleanup (i use warm water). i would use raft only for object with very very small footprint. – darth pixel Sep 28 '17 at 07:44
  • Thanks for the support guys! I tried printing a few things without a raft today and they worked perfectly! – Matthew Sep 28 '17 at 18:57

3 Answers3

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As comments suggest, a raft is not all that popular. Consider using a brim/skirt instead. I've had excellent luck with a 4-mm skirt, printing onto blue painter's tape. (Unless you consider it bad luck when I have a devil of a time getting some parts to release :-) ). Skirts are trivial to cut free from the object.

In a similar vein, if you run into trouble getting support structures to pop off the object cleanly, try to make them as thin-walled as possible.

Carl Witthoft
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I have been able to get rafts that peel off by editing the g-code after the raft has finished and adding an M104 set temperature command telling my printer to cool the nozzle down to about 40 degrees and then another M104 command to tell the nozzle to heat back up again. This gives the raft enough time to cool and then the raft doesn't weld to the rest of the print. If you are using a heated bed I would suggest trying the M190 command and turning that off after the raft and then back on after the first layer as well.

user802599
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    Is letting the nozzle cool and heat up again just a hack to get the printer to pause? In that case, you could just use `G4 Sxx` where `xx` is a number in seconds, instructing the printer to wait. – Tom van der Zanden Oct 23 '17 at 06:23
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I use raft almost always for ABS and PLA. My favorite setting for gap is somewhere between 0.11-0.13 mm both for 0.1 and 0.2 mm layer height.

By using 3-4 layers of raft I always get predictably good quality of a lower layer and not have any issues with removing prints from the surface which I had without using raft (especially with large or weak prints)

Mikhail Z
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