Corners warping

[naturalstate720]

I'm new to 3d printing and am having trouble figuring out why my corners are warping. Is it likely a bed adhesion issue?
I'm printing PLA w/ 215 nozzle & have tried many temps on bed 40-85. I've tried the elmers purple and frutis. And about 15-30 minutes into a larger architectural prints w/ big simple bases, the corners always warp. It's usually the same corner that is always the worst.

The skirt and first layers always stick fine, it's just later in the print that the corners eventually come up.

We bought the machine pre assembled. I've checked the gap, and from as far as I can tell it is .006 with good resistance. I printed the squares and changed the multiplier to .92 based on caliper readings.
The table is a little shaky that we have it on, could that be the problem? Or is it likely a bed adhession issue, or could it be that my bed is actually unlevel. Getting frustrated, I didn't realize this printer was going to be so difficult to learn how to use.

I've attached a couple photos of the corners.

Thanks for any help.

[Jules]

In addition to your other post, (where I put most of the suggestions), take your nozzle temperature down to about 205C. It will also help to reduce the differential.

[naturalstate720]

Sorry, I didn't realize I was waiting approval for new registration and just thought my post wasn't successfully posted.

[Jules]

No prob. Welcome to the group!

[3dPrintingMD]

I'm assuming your printing on glass.

I am new to all of this, but I have printed a ton of things so far.

The answer to your questions is hairspray or glue stick. Pick your poison.

Hairspray is messy and harder to remove from the glass. But does not leave any noticeable residue on the printed item.

Glue Stick will hold it down, and hold it down but good. You will normally have trouble separating the item from the glass afterwards until it really cools. However unless you get a perfectly even coat of gluestick, it will leave a residue on the item.

When I started having warping issues, I went to glue stick, since I had it in house. But I have since moved over to hairspray.