Why did it not stick to the bed?

[ppolla 6]

So I wanted to try an overnight print. Let it start its 14+ hour journey yesterday evening and upon waking up at 7am this morning this is what I found....

Print size: 78/45/101mm...so a bigger robot!

Robot was moving around on the heated bed....it didnt stick. As you can guess I didnt use the glue....

Any idea why this happened?

Could it be room temperature that caused it? We dont have heating overnight and I did leave one window a little open. Overnight outside temperature drops to 4-5C.

Please advise.

In mean time, I started another print.

Thanks!

...no idea why its turning the photo...

Edited January 23, 2016 by Guest

[Dim3nsioneer 557]

Operating temperature of an UM2(+) is 15-32°C. At 5°C ambient temperature you cannot expect the layers to stick together.

[ppolla 6]

Operating temperature of an UM2(+) is 15-32°C. At 5°C ambient temperature you cannot expect the layers to stick together.

 

sorry....5C was outside and window was only open maybe 7-8cm...

ambient was for sure above 15C

[Dim3nsioneer 557]

OK. Well, 15°C is not ideal, but it should work somehow. Usually you get angel hair when the adhesion to the last layer is lost. This happens if you suddenly print in thin air (skipping of the x or y motor) or if you had a temporary underextrusion. This could be caused by some additional resistance at the feeder (filament entangled?).

[ppolla 6]

OK. Well, 15°C is not ideal, but it should work somehow. Usually you get angel hair when the adhesion to the last layer is lost. This happens if you suddenly print in thin air (skipping of the x or y motor) or if you had a temporary underextrusion. This could be caused by some additional resistance at the feeder (filament entangled?).

 

So in winter, how do you get proper ventilation if the window is not open? By doing this temperature will drop....

I have lots to learn, and honestly I dont know how to avoid the above situations you mention. I have not closed the window and am trying again...

[Dim3nsioneer 557]

Well, as long as you are not printing ABS but PLA or e.g. XT there is no harm from nanoparticles or fumes in a non-ventilated room.

btw: there are ventilation systems with heat recovery. They should exist even in the land of energy waste (called USA ).

Edited January 23, 2016 by Guest

[ppolla 6]

Well, as long as you are not printing ABS but PLA or e.g. XT there is no harm from nanoparticles or fumes in a non-ventilated room.

btw: there are ventilation systems with heat recovery. They should exist even in the land of energy waste (called USA ).

 

haha....am sure there are. As a european I can say there are good and bad things about the USofA!

Edited January 23, 2016 by Guest

[yellowshark 153]

Lol well I have printed PLA the last three winters (and summers) with the window closed and I am still living, I think.

[JohnFox 25]

You really must use PVA glue for PLA and the heated bed.

Once the object starts to move around that's the end - you get the tangle.

Don't think it was the room temperature, I often run at 15C.

Simply the first layer not sticking to the bed. PVA glue solves this 100%. At the default 60C bed temperature and glue, you simply cannot pull the object off the bed.

[yellowshark 153]

Ok I am going to go in a different direction. I am surprised you think the ambient did not go below 15c, I actually doubt that. I am guessing you were probably circa 10hours into the print. Therefore to me it is extremely unlikely that it came off the bed due to temp. unless it really did drop to a low temp. I never print below ambient of 20c so I have no idea what would happen.

3d prints can develop spikes. These normally happen at corners, or if there is retraction they can happen where the extruder leaves the model or enters the model. I have not really studied it but I suspect printing too hot or fast will increase the probability of it occurring ( I guess not running fans may contribute too). Once they start they just get bigger and bigger; to a point where the extruder finally hits the spike when it is solid and the model is knocked off the bed. There have certainly been times when I have baby sat a print, using a screwdriver to push down the soft deposited filament each time a layer is printed.

[ppolla 6]

i have no idea what happened...but after restarting and using the glue that I received with the printer things are looking better...

in past few days I printed many things without the glue without any issue!