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I have been trying to print an object that is 4 inches tall. About at 3 inches it falls off the bed. I am using tape on the heated bed and right before the print I am wiping the bed with rubbing alcohol. After the first time I tried hot gluing it to the bed when it was mid way through so that it wouldn't fall off but that didn't work. I am printing at 185°C and the bed is 55°C. I am using PLA to print. Should I increase the temperature of the bed or is there something else that is wrong?

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  • $\begingroup$ Possible duplicate of Can't get print to stick, no matter what I try $\endgroup$ – Carl Witthoft Feb 21 '17 at 16:53
  • $\begingroup$ It's all about levelling and setting z-zero. $\endgroup$ – Carl Witthoft Feb 21 '17 at 16:53
  • $\begingroup$ I thought at first that it was a leveling and zeroing issue, but the problem, per the post happens after a couple inches has printed. That points more to temperature than to calibration issues. If the bed is nearly the right temperature, the hot filament will transfer some heat to the bed, but it might begin cooling to a "release temperature" by the time it reaches the problem point. $\endgroup$ – fred_dot_u Feb 21 '17 at 22:44
  • $\begingroup$ @fred_dot_u Should I raise the bed temperate? $\endgroup$ – Loanb222 Feb 22 '17 at 0:30
  • $\begingroup$ Tell us what tape you're using and if it's not blue painter's tape, consider to change to that. Yes, also consider to raise the bed temperature by 5°C between test runs. $\endgroup$ – fred_dot_u Feb 22 '17 at 0:35
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Even though knowing the model of printer is slightly helpful, it's not critical to making your print work. Your PLA manufacturer should have recommendations for both the bed temperature and the nozzle temperature. Is your print bed glass or metal?

As an example, my bed is glass and I set the temperature to 70°C for PLA, but the real temperature at the bed is slightly lower than that.

I'm using 3M brand blue painters tape. What type of tape are you using? It will make a difference. I originally used cleaner on the tape, but found it was not needed. Blue tape means parts stick so well that you have to get them free before the bed cools too much, or you'll have to remove the tape to get the part free.

My PLA nozzle temperature settings range from 190°C to 230°C, depending on the filament. I use the manufacturer's figures and vary them five to ten degrees depending on the results.

Too hot at the nozzle will burn the filament possibly causing a clog, while too cold will cause extruder feeding problems. You did not reference having feeding problems, which implies your nozzle settings are acceptable.

Consider to change your tape and to increase the bed temperature. At a 55°C starting point, you could jump five degrees at a time until you get a good bond.

Also be certain that your bed is level and properly calibrated. The first layer should apply in a slightly "squashed" manner. Too close and the nozzle tears up the tape, but too far and the filament will sit on top and not properly adhere.

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You might also try tweaking your settings to add a "raft", which is a wider area surrounding the first layer of your print. The added area is more area to "stick" to the build plate (or tape, or whatever). I've found that often helps.

I've tried using crazy glue in a pinch, to glue down a corner that's coming loose, but as you reported for hot melt glue, it's a long shot. I did get it to work once or twice.

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Well, I had the same problem like you. I tried some raft but the result was ugly and a little hard to remove it from final part.

I notice that autolevel works fine but, if your printing on top lines are over warping the nozzle will collide until the part fall off the printer. So is needed to minimize this warping controling speed and temperature, maybe the PLA is getting glued to nozzle and creating the warping.

I have set the printer from 185 and 190 to 210 for first layer to increase the adition to tape, the heat bed to 32 degrees to allow the first layer get cold faster to avoid PLA warping. This may vary depending on city climate

Remember the heat bed is to control room temperature close the part, not to mold or to print the part. At least, that you are printing a turkey to be finished and cooked.

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If you have a dual-extruder printer, your second nozzle could be hitting the part. As the print grows taller, each hit with the nozzle has more chance to knock the part off the build plate.

This can happen from some of the following reasons:

  • Nozzles aren't level to each other
  • Build plate is not level
  • Material oozed and solidify on second nozzle. (Similar to nozzles aren't level)
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Check your Z-calibration. I have a similar problem that I'm about to investigate. I have a feeling the Z-axis pulses per mm may need to decrease ever so slightly. The cumulative error may lead to the extruder poking at finished layers as the part gets taller.

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