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3D Printing a rounded base - Problem.

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I got this strange dripping artifacts on the bottom of my 3d model. I know is cost by overhands but is there a way to fix this problem like temperate or print speed? I tried speed 30 and Temperate at 200 using PLA. I also notice that from the start of the bottom print. The nozzle is pushed into the printed base as it slowly print up from the bottom of the rounded base. Is my print bed set to close to the nozzle that it does not have enough space for the filament to set?

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The only really good way to deal with overhangs is to use good cooling, do you have that on your printhead?

If you cant get proper results with that, you use support structure under the overhangs to give them something to build on, the cut them away after the print is done, and sand and polish the "scar"...

You can create the supports yourself in your modeling program of choice, generate som clever ones using eg. meshmixer, or let your slicer generate some (less clever ones) for you...

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The only really good way to deal with overhangs is to use good cooling, do you have that on your printhead?

If you cant get proper results with that, you use support structure under the overhangs to give them something to build on, the cut them away after the print is done, and sand and polish the "scar"...

You can create the supports yourself in your modeling program of choice, generate som clever ones using eg. meshmixer, or let your slicer generate some (less clever ones) for you...

I did use meshmixer for this print but as I found out there will be alot of small bumps as its generated to support the rounded base. Has anyone successfully printed something like a sphere/ Xmas ornament in one print? Good cooling? You mean it has to cool the PLA faster to get a nicer shape? How do I mod my ultimater2 for this? I got limited resources...

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It could also very well be the heat radiation coming from the heated bed.

I am assuming you have an Ultimaker 2?

Try to slice it at 60micron, a low printing temp like 190º and 35mm/s (if this works depends on each color or filament manufacturer, so tweak at will) and turn off the heated bed. Instead, use blue M3 tape for adhesion.

Rotate the part with the overhang towards the (for the viewer) left fan, that may also help.

Good luck!

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It could also very well be the heat radiation coming from the heated bed.

I am assuming you have an Ultimaker 2?

Try to slice it at 60micron, a low printing temp like 190º and 35mm/s (if this works depends on each color or filament manufacturer, so tweak at will) and turn off the heated bed. Instead, use blue M3 tape for adhesion.

Rotate the part with the overhang towards the (for the viewer) left fan, that may also help.

Good luck!

Yes SandervG! Im using Ultimaker2. How do I set 60micron in Cura? 0.06mm? Hmm... I will try that. What about the other problem? I notice the nozzle been pushed against the printed object like rubber. Is my print bed set to close to the nozzle?

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What settings do you mean?

For the Ultimaker Original+ you can select all the settings you need in Cura. So usually you shouldn't need to change anything prior to a print.

But if you must know, you can create your own profiles in Cura.

Most settings are saved from your previous slice.

Depending on what settings you want to tweak you could also create 'a new machine' with your special settings.

For the plug in, if you enter 6mm, the pauze will be at a 6mm height.

For you you can not yet click on a place in your 3D view to select the spot where you want it to pauze.

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What settings do you mean?

For the Ultimaker Original+ you can select all the settings you need in Cura. So usually you shouldn't need to change anything prior to a print.

But if you must know, you can create your own profiles in Cura.

Most settings are saved from your previous slice.

Depending on what settings you want to tweak you could also create 'a new machine' with your special settings.

For the plug in, if you enter 6mm, the pauze will be at a 6mm height.

For you you can not yet click on a place in your 3D view to select the spot where you want it to pauze.

By default, My print temperature will always go to 210. But I want it to always start with 200 or lesser. How do I do that in cura?

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Well, based on the drawing and subscription I would say it sounds like over extruding, but that doesn't really happen that often.

Are you printing with Ultimaker filament?

What filament diameter did you set in Cura?

Is your flowrate (in the tune settings) still 100%?

Does it only look like so when printing, but in the end the surface quality is good?

- or does it also leave strange artifacts on your surface?

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What settings do you mean?

For the Ultimaker Original+ you can select all the settings you need in Cura. So usually you shouldn't need to change anything prior to a print.

But if you must know, you can create your own profiles in Cura.

Most settings are saved from your previous slice.

Depending on what settings you want to tweak you could also create 'a new machine' with your special settings.

For the plug in, if you enter 6mm, the pauze will be at a 6mm height.

For you you can not yet click on a place in your 3D view to select the spot where you want it to pauze.

By default, My print temperature will always go to 210. But I want it to always start with 200 or lesser. How do I do that in cura?

5a330d2978cee_Schermafbeelding2015-04-29om16_22_03.thumb.png.631ccbcf536ccdae1d8c803f939f8233.png

In Cura you can set the temperature for your print. If you look at the image you can see I have set it to 200ºC in this case. When this print starts it will auto heat to 200ºC instead of 210ºC. These settings can be accessed through full settings.

5a330d2978cee_Schermafbeelding2015-04-29om16_22_03.thumb.png.631ccbcf536ccdae1d8c803f939f8233.png

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Well, based on the drawing and subscription I would say it sounds like over extruding, but that doesn't really happen that often.

Are you printing with Ultimaker filament?

What filament diameter did you set in Cura?

Is your flowrate (in the tune settings) still 100%?

Does it only look like so when printing, but in the end the surface quality is good?

- or does it also leave strange artifacts on your surface?

So far. Most object I printed are ok as it has a flat base. I only notice this problem when I start printing my own model ( round base object ). Yes the flowrate is 100. I think i am using Ultimaker's filament ( my first roll ). I not sure about the diameter :p I will need to check tomorrow. Over extruding? but after it printed to a high, it start to look normal.

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Ok, I think I already know.

What you are most likely seeing is the following:

During printing the printhead needs to build up pressure in order to extrude.

When you are printing an overhang, the pressure can push the shell down a little bit because, in contrary of a wall straight up, it is only partly supported by the previous layer. Printing thinner layers could help.

Sounds like a complicated explanation, hopefully it makes sense!

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It is possible to set the temp in cura but it's MUCH easier to simply modify your PLA settings on your UM2. Go to the filament menu and choose CUSTOMIZE. Change the temp to 200C then scroll to the bottom and save it and then choose where to save it to: PLA. That last step is not obvious (choose where to save it to).

Then always in the future it PLA will have a new printing temp. Note that if you print on tape (which you don't) 200C is much too cold for the bottom layer but with a heated bed even 180C is plenty warm enough.

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The bad quality you see on overhangs is a problem with all FDM 3d printers. You can get better results with higher quality filaments. Overhang ability varies greatly by filament brand. corners are the worst (overhanging corners like the bow of a boat). You should be able to get absolutely perfect looking overhangs if they are at 45 degrees. As you get closer to horizontal it gradually gets worse - you get a raised lip starting near the corners of your overhang or the entire edge in your circular case. Each layer is worse than the last until some of the filament is pushed out over the edge. It's possible to remelt the lower layers if you slow the head to 5mm/sec but that's not a reasonable solution (although some have tried it on every other layer and it makes a better quality). Increaseing fan and lowering filament temp is a better solution. Try a small desk fan and blow it right on the print from outside the printer. Make sure it isn't so strong it cools the nozzle (not likely). Make sure your fans are at 100% within the overhang region (by default they aren't up to 100% until 5mm up).

The basic problem has to do with the nature of PLA - it cools very fast but it doesn't solidify until well below 100C. So it because this stretchy liquid rubber band material (like snot) and pulls inward on outer corners. For vertical walls the layer below holds it in place but for overhangs it gets pulled inward and upward.

Some brands of PLA are MUCH worse than others.

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To set temperature in Cura you can switch the machine settings to "rep/rap" mode but I strongly don't recommend this. You can also use a plugin that changes temp on different levels but that won't get you control over the starting temp.

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I can over-right the default PLA temp? I will try it tomorrow! I think I going to off the heated bed first and maybe applying the glue stick to try the rounded base print.

Still... now Im puzzled by why I dont have the temperature setup in my cura?

 

It is possible to set the temp in cura but it's MUCH easier to simply modify your PLA settings on your UM2.  Go to the filament menu and choose CUSTOMIZE.  Change the temp to 200C then scroll to the bottom and save it and then choose where to save it to: PLA.  That last step is not obvious (choose where to save it to).

Then always in the future it PLA will have a new printing temp.  Note that if you print on tape (which you don't) 200C is much too cold for the bottom layer but with a heated bed even 180C is plenty warm enough.

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There are two ways to produce gcode files: reprap or ultigcode. reprap mode is the older method and includes 6 or so settings that ultigcode does not. This is because those 6 or so settings are set on the printer. When you switch to reprap mode those settings are ignored on the printer and it uses the values in the gcode. The point is for portability among printers and filaments.

Those settings are (I probably forgot some): nozzle temperature, fan, bed temp, retraction distance, retraction speed. These settings should all/mostly be settable in the filament settings on the UM2 or in Cura if you tell it your machine is a reprap style printer.

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Here is a video I shoot. Was trying to print a 5cm size sphere. I set the print bed temperature to '0', print speed at 20 and fan at 100%... as you can see its still may give that deform bottom... I know I may have to break my model into parts to solve this problem. But I just trying to find ways to minimize the need for that.

Tried the customize temperature setup. Nice! I did not know that. Still which to have cura have the temperature setting back in. I sometime forget to set the temperature first before i start to print. I dont want to change it half way as it will easily break on the lay that the temperature was changed.

 

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