PETG filament problem

I know this is not the correct forum but my machine is a corexy.
I have been printing for a few years with PLA and decided I should try PETG. -- disaster --
What settings do I need to alter for PETG?
I have raised the temp by 5 degrees and turned off cooling.
The filament will not stick properly to the glass
The layers are not bonding enough
I am getting stray blobs

Can anybody help or direct me to relevant information.
Thanks
Paul

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My PET-G prints are always flawless. Actually I make more mistakes with ABS and PLA.

Here's the details:

- filament is Devil Design
- print speed max is 100mm/sec
- cooling is always max after the first layer
- the bed is PrintBite (search this forum)
- bed temperature is 65-70 degrees C
- hotend temperature is 240 degrees C

Edited 1 time(s). Last edit at 10/18/2017 06:03PM by sigxcpu.

First layer speed should be slow ( 20-25mm/sec)
The nozzle surface should be clean, otherwise the filament sticks to it.
Depending on your print surface the 1st. layer "squeeze-factor" should be lower than with PLA.

I find PET-G to be quite forgiving. I've had success with bed temperature between 50 and 70 although I do use 3dLac. I have printed it as low as 200 deg C but find 220 is best on my machine, with my hot end etc etc. I only use cooling on fine detail and bridges.It is does have a tendency to stick to the nozzle if it isn't clean and also a tendency to be stringy requiring a bit more retraction. It does absorb water so needs to be kept dry. For me ESun PETG was an absolute disaster but many people get on fine with it. Mine printed like it had been immersed in water for a week even though I used it straight out of the vacuum packing. Probably just a bad batch but it's put me off using their filaments for life. It can get ground away by the extruder if you print something with a lot of retract/unretract cycles but this is more of an issue with a mixing hot ends where the filament may not be moving forward. I've had good results using FilaPrint PETG as here [forums.reprap.org].