Prints won't come loose from TAZ5 bed

When I first started printing with my TAZ5, I wasn’t having much luck with HIPS or ABS. However, the parts would fall loose from the bed when the bed cooled. Now that I’m getting really nice prints, I’m finding that the parts don’t want to let go of the bed. Again, this is the TAZ5 bed. I’ve found that I can use a can of compressed air, turned upside down, to freeze the part off. This works very well for small parts, but larger parts are still very difficult to remove. My bed is beginning to delaminate. I don’t use “lulzjuice,” or “ABS juice,” and the parts stick just fine without it. Does anyone have any tips on how to remove the prints without damaging the printing bed?
Thanks.

The TAZ 5 has a PEI bed so do not use anything on it (Acetone mix, glue…) First off make sure your bed is dead level (really, really level) then just raise the Z axis end stop up a bit and the parts should not stick down so bad. The PEI is excellent but it does require a perfectly level bed and a very light touch of the extrusion (not pressing the plastic into it hard).

Without the PEI the prints would not stick at all with the setting of the Z axis higher but the PEI seems to hold it well.

I use a painters pallet knife (spatula) to undo my prints and even large area prints come loose fairly easy with it as long as the Z axis is right.
Spatula.jpg

When you print, do your parts have any print lines on the bottom of the part? I’m finding that if mine have print lines, they are easy to remove, but pull up while printing. I agree that my Z is close to the bed, but the larger prints seem to require it or they pull up. Also, they are perfectly smooth on the bottom. Maybe I just need to play a little more with the z-axis height, but the thing is so darn touchy.

Mine come out pretty smooth. The difference in a good bottom and not is only about 1/16" of turn on the Z height.

I find the Z-endstop pretty touchy too. You’re doing the right thing to inspect and get information from the way the bottom looks. No lines on the bottom probably means the nozzle is too close… a sixteenth turn on the knob should help.

Try using the Z-offset setting in your slicer software. Print a 10x10x20 block. Remove, judge how well it sticks. If too well, print again and set the Z-offset to .2 or .1. Should be a bit easier to remove… Its a bit of a trial and error, but I find the Z-offset in software is easier to manage than the endstop knob.

If you’re using the Z-offset to adjust past .5 or 1 then give the endstop knob another twist. I go back to the business card check… home the Z, and try sliding a business card between the nozzle and bed. The card should slide through with some friction felt.



The last thing is to wait for the part to cool to 50C. I like to set the bed temp to 70C with an 30-60 minutes to go… if I remember. :slight_smile:

There was also a tip about using seeping drops of isopropyl alcohol between the print and bed to help with removal. A drop or two of IPA at the base of the print… The only issue I have with this, is that the IPA supposedly dries out the PEI.

I understand what you’re saying about the first layer being too squished into the bed. I’ll try to make adjustments so that doesn’t happen. I’m wondering though if there are tips on how to get it loose if it does happen to squish into it. I tried the IPA trick but it didn’t work for me. I wonder if heating the bed up and cooling it back down again would help, or heating it up hotter than I ran the part, then cooling it back down. Maybe, instead of spraying the bed with freeze spray, (which works really really well but causes the bed to delaminate) I should just put a few ice cubes on it. Some things I’ll have to try.

Pliers. :slight_smile:

Well if you’re willing to sacrifice the part, heating the bed to 110C+ might soften up the bottom to get a tool like tmorris9 suggested underneath the print. I like a dental spatula… which might be a tad thinner.

Thinking about this further, maybe more squash and raft might make a good mix to release the print…

I was just looking at this…
http://www.adafruit.com/products/2132
Interesting.

Those PrintINz Plates work great. They are only for PLA, however.

When I use ABS I use the PEI. When I print in PLA, I use the PrintINz plates since I have never been able to get PLA to stick to the PEI.

Kenny