object not staying on bed

I am fairly new to 3d printing and my objects keep lifting off the heat bed. I have the temperature set on 75 degrees with aluminum tape that I sprayed with hairspray. After about 20 minutes the extruder is about to put on the next layer and it just picks up the object. Does anyone know how to fix this?

Are you printing with PLA or ABS (I presume PLA ?)

How tall are the objects when they detach from the bed, i.e 20 minutes could be 100 layers high?

What printer are you using, does the bed move or just the XY print head (or XYZ head)

This subject has been done over and over again on the forum.
Causes for non-sticking are numerous and it will depend on your setup before people could give you a educated response

I am printing with PLA and i am using a mendelmax 1.5. It takes about 15 to 20 minutes for it to come off. Also the bed moves.

Glass (as in cheap window glass) is the most common bed material for many of these printers. It's smooth / flat / cheap and heat proof. Not all hair spray is created equal. You need some that's made to hold down hair during a hurricane.

@printer_man58

OK. I have a MendelMax 1.5.

With PLA, I use Kapton tape on glass for PLA and its OK, but it depends on what you are trying to print.

Anything with a large surface area e.g. a cube should be OK, however I've found problems printing hollow tubes, end on, as this isn't enough surface area of the end of the tube to cope with the mass of the model as the print gets taller.

Depending on what slicer you are using, you could turn on a "brim" or "raft" or you just add some sort of support material to your model before you print it, then cut of snap the material off afterwards

Another issue can be printer speed, I've had prints that have shaken or been vibrated off the bed, when I print items with thin walls, but where the walls are sufficiently thick that Slic3r starts to use zigzag in fill. These short infills e.g. 0.5mm long strokes, are printed at infill speed (ie much faster than the perimeter), and shake and vibrate the print bed so much that it can dislodge the print.

Another possible cause is that the edges are cooling too quickly or cooling excessively. i.e if you are printing in a shed or garage that has a cold draught, this can cause the edges of prints to start to come unstuck and this can lead to the whole model coming unstuck, but in your case it doesnt sound like this is your causing your problem

Quote
uncle_bob
Glass (as in cheap window glass) is the most common bed material for many of these printers. It's smooth / flat / cheap and heat proof. Not all hair spray is created equal. You need some that's made to hold down hair during a hurricane.

Back when I had (more) hair, and we used to hit the rock clubs, Final Net was the thing for big hair. It was not uncommon for some guys to use more than a can at a time. As to glass I've been wrestling with this one, as the vendor who supplies borosilicate to my heater vender evidently thinks my last name is Gates. So I was talking to a glass shop, who recommended tempered glass, which starts at around 40 bucks in my neck of the woods, and is supposed to be good to 700f.

I am also a fan of the cosplay and I sometimes buy the cosplay wigs from the online shop to make my character looks real and I alo use the hair wigs in my daily life as well to help me change my hair style. Last weed I bought a short hair wigs and it suit me very much and just spend me US$60 only.

Edited 1 time(s). Last edit at 12/07/2013 01:34AM by Hunter11Rilley.

The reason the hair spray works is that the ingredients are water soluble plastics. The more extreme the spray, the more plastic they put in it.

For the brim would it have to be a certain layer or height?

You normally set a brim or skirt to a single layer.

Another big contributor to parts staying stuck is the bed being properly leveled. If you are printing a 0.3 mm first layer and the calibration is off by 0.15 mm that's a problem....