# Specific 3D Printers, Scanners, & Hardware > CTC 3D Printers >  Upturned corners, strings, and prints that look like they're melting.

## TiredJuan

I've been changing settings (and leveling the bed) like a madman, but I can't make any progress. I had gotten semi-decent results with some minor ringing:
20151230_114807-1.jpg (bad photo, but it gets the point across.)

In an attempts to defeat the ringing effect I mounted the base the printer is sitting on to the wall using one angle brackets and a few screws. But my prints immediately became worse:
20160102_095614.jpg20160102_095533.jpg (This isn't the original attempt, I lost that one in a fit of rage)
In the first print that failed like this, his arms had little strings between them, and he was warped like this. After some Googling and trial and error, they never really became better. The picture above is attempt No. 9.
The print head has been leveled about 4 times during these prints and it doesn't seem to help much (but it did help slightly.)
Changing the temperature changed very little, above was printed at 175C where the original was at a much higher temperature.
I bought a caliper to test filament diameter, and was pleasantly  surprised to find it was fairly uniform at 1.72 +-0.01

The problems seem to start at higher layers? Perhaps it's only more noticeable because of the rounded edges?
Guides like this is where I've been going to try and diagnose my prints (but I don't use Simplify3D, I'm hesitant to spend the money when I haven't had but 1 or 2 almost decent prints.)

I don't know where to go from here. Any help would be appreciated.

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## TiredJuan

Here's what's going on while printing, if it helps any.

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## ServiceXp

What is the Material being used?

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## curious aardvark

if he's printing at 175 - then it's pla.  I never print pla that low - 210 is my standard temp for pla these days. 
I find that as long as you have active cooling the higher temperature gives much cleaner and stronger prints. 
That said I'm using very good quality filament most of the time, but the cheap white pla I've got in my right extruder also works well at that temperature. 

What temp is the build plate ?

Looking pics - you need to change several things. 
1) change your slicer - that raft looks like the one from rep-g - the worst slicer there is. 
2) you need active cooling on the print area itself - this will fix most filament issues with 3d printing pla and quite afew with abs as well. 
3) with pla you don't need rafts. so switch them off and give your printbed a few coats of pva with a gluestick and run your buildplate at 50-60c.

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## TiredJuan

Sorry, it's PLA. The prints pictured are .27 per layer at 30mm/50mm for speed settings. 10% fill and 1 or 2 shells (amount of shells didn't make much difference in quality)

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## TiredJuan

Bed temp is ~40. I was having issues with the first couple of layers collapsing and the suggested fix was turning bed temp down. As far as slicers go, I've yet to get anything but repg and makerware 2.4 working. It's got an older firmware (7.2 is reported)  that I can not for the life of me get to update. 
As for the cooling: I don't think that's the issue. In fact the print from the video cooled enough that shortly after it came into contact with the head and popped off of the bed (this was a first).

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## bigo93

Just updated my CTC printer and this video guide tells you exactly what to do!




Pressing the update button and the button on the back of the printer does take quite a few goes.
I found the best thing to use was the spare fuse I got with the printer to press the button on the printer.
But even then it took me like a dozen times before it updates.

As the video says, when you do the update, just tip the printer back a bit and see if the green light starts flashing.
If it doesnt and you just see the normal red light on, wait for the program to say update has failed and try again.

Again, dont forget to stop makerware services when using repg
And apparently best to stick with 7.6 even though there is a 7.7 out, as there are sd card problems with 7.7 or something.

You can get the lates sailfish regp from http://www.thingiverse.com/thing:32084/#files


It hasnt however fixed my circles coming out as ovals  :Frown:

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## Alibert

I am still convinced it it a cooling issue. In the vid you see the plastic bending up and down as it is still quite rubbery. This points to the fact that it doesn't cool off enough to become rigid enough to withstand the dragging force of the nozzle pulling molten plastic over it. This is most evident when the nozzle makes a curve movement.

 PLA has a very low glass point (temp where it becomes rubbery) of around 65 C. This is why when printing PLA it is usefull to have a cooling fan. Remember that the nozzle is radiating heat as well, so with a small object and the nozzle hanging over it all the time the PLA will cool slowly. A plastic like ABS has a glass point around 105 C and you never use a cooling fan there. The cooling fan is not the one you see on the front of your extruder as that one is intended to cool the heatsink and not the printed object.

There is an easy test to see if it is the PLA cooling and that is to do the same object in ABS. Use all the same settings (and with raft), only use a nozzle temp of 230 C and a bed of 95 C. Your printer most likely came with a free spool of ABS as well? You can use the other nozzle to load the ABS.

If the ABS also comes out wrong, then one must look elswhere such as z-axis steps/mm and extruder steps/mm. But I doubt that the problem lies there.

If you want to stick with PLA, try printing two objects at the same time with some distance between them. Load the object twice and place them a bit apart on the bed. Then slice it. This way the nozzle will move alternatingly to both objects. This more than doubles the cooling time per layer per object, and also the nozzle is only over the object (and radiating heat to it) half of the time. It might introduce stringing between the objects though.

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## TiredJuan

I've updated the firmware (using Arduino methods) which has introduced other issues, most of which I have worked through. I can't test ABS due to the location of my printer, and lack of filtering/venting in that area. I will be moving to ABS after things warm up outside and leaving it in the garage won't be an issue. I will try printing multiple objects when I get off work, and report back after that. 
As for the reason I don't think heat is the issue, it's due to just how much the corners are pressed during that video. It may be hard to see, but it looks like it presses them down 2-4mm which leads me to believe the extrusion multiplier or z-steps are the cause. Either way, I will try multiple object prints to see if that helps. 
If heat ends up being the issue, where can I purchase a cooling duct for a fan? I realize I could print one, but it would be nice to purchase one as my print may fail yet again.

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## EagleSeven

I keep a long bladed knife handy to push-down those warping (Up-turning) overhangs, when they start.
(Push them a little Past level, then they spring-back to level, before next layer is extruded)
I call it 'High-speed Sculpting'  :Wink:

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## TiredJuan

This might be a good way to get a fan shroud printed (so I can again print a better shroud.) Thanks for the tip.

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## TiredJuan

Alright, so heat is an issue. I intentionally spaced them semi-close to see if the shoulders that were closest would be problematic (They weren't.)
That being said, they weren't particularly great, and I had to press the corners down as suggested by EagleSeven, but it's definite progress.
20160103_093716.jpg20160103_093729.jpg20160103_093818.jpg20160103_093848.jpg
For those curious: this was printed with 10% infill, .27 layer height, with a single shell. Feed 30, travel 40, temp 190.

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