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3D Printer Essentials? (Or maybe better named as "Adventures in Newb 3D Printing" )

lcdguy

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While I have people's attention... anybody ever use one of these USB ISP burners for flashing firmware? If so... I'm assuming the power should be removed from the board that's being flashed? Can I go so far as to uplug the board completely (other than the flasher of course.... ;) ).

i didn't have one of those when i did my mod, i just used an arduino. but it's probably safer to try it with no power first and have nothing happen, then to have power applied and something exciting happen. :)

Also this is the filament i use mostly now a days, never had a part snap but then again never really tested the tensile strength either.

 

Entz

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How thick are the walls? It may simply be there isn't enough meat holding it. Z direction is the weakest, things break at layer lines pretty easily.

I am curious if you tried colder (say 230) or hotter or no cooling if it fixes it. I don't have experience with that brand.

Regarding the programmer no sorry :( . I update mine directly over USB via the Arduino IDE.
 

sswilson

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Heh.... but letting out the magic smoke is always an interesting time.... :)

Just realised that turning off my cooling fan will probably result in crappy overhang which will affect my current print... think I'm going to tune it back up to 50% once the first few layers get printed.

As far as walls go.... the cube that snapped on the bottom is a 2mm base with default print settings (.8 X4 ?)
 

lcdguy

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Heh.... but letting out the magic smoke is always an interesting time.... :)

Just realised that turning off my cooling fan will probably result in crappy overhang which will affect my current print... think I'm going to tune it back up to 50% once the first few layers get printed.

As far as walls go.... the cube that snapped on the bottom is a 2mm base with default print settings (.8 X4 ?)

what about infill % and infill pattern (if less than %100) ?
 

sswilson

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20% Cura default and I believe "line". That said... this same print is rock solid printed in PLA so I don't think it's the slice settings.... either my cooling, the printing temps, and/or the filament itself.

The extrusions feel almost "brittle" and behave like you'd expect improperly tempered steel to behave.
 

lcdguy

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not sure then, could be a temp issue or maybe some bad filament i know it has happened in the past where filaments end up being brittle, though it's rare. Might be worth while trying some different brands as well, or if you have the link to what your printing to test and your temps w/ other print settings i can try printing one on mine and see if i get the same result though i would be using a different printer and brand of petg.
 

lowfat

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How thick of a part are you talking about? If you are trying to break something that is only like 1mm it absolutely will explode when it is stressed passed its limits.
 

sswilson

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Thanks for the offer, and I might hit you up after I run some more tests myself, but I'm still focused on the fact that the print works fine in PLA and am going to try some different temps/cooling settings.

Even the support pieces seem weird. I can easily snap them and the walls/infill seem awfully thin.... maybe there's something off with the Cura Generic PETG settings.... I'll try a brand name setting to see if it makes any difference.

How thick of a part are you talking about? If you are trying to break something that is only like 1mm it absolutely will explode when it is stressed passed its limits.

In the case of my 3 sided cube.... it's a 2mm base and again, there's no way I can snap my PLA cube(s) the way I managed to snap the PETG one. Maybe I'm looking at this too hard, I'm just concerned because the parts I'm currently printing are partially structural to the head and I wouldn't want them to fail.

edit: and yes... the second part to fail was definitely a thin walled part (it was the wire guide from the bullseye base) that was stressed with a zip tie so I'm not overly worried about it.
 
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sswilson

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Yeah, the thing that stands out on that one for me is the fact that fan speed is set to 30% max 50% which corresponds to the information I was seeing before posting in here. The Cura default settings (just looked) are pegged to 100%.
 

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