OK, so I have tried to search the forum and internet for detailed instruction on how to print ABS without a heated bed. I have a lot of information but the best advice would be from someone with experience using the same printer as me (Gmax 1.5 XT). If anybody would be kind enough to give me a best practice (from the start) guide on how to improve adhesion or possible modifications for printing good quality ABS, I would be very grateful.

Thanks so much
It is on our schedule to work on the troubleshooting and tips portions of the forum this week and we will be giving tips on how to print with ABS. Here's some tips from an email we sent to hold you over:

Found this post in the forum that answers my question. Hope this new post is easier to find for future questions.

Quotes from Gordon:

"As for ABS I recently experimented with zen toolworks bronze ABS with much success. I tried several methods including heating the bed/print area with a heat fan (which I don’t recommend since it causes the extruder parts to warp due to the plastic getting so soft) and the best solution is this:

1. Sand the bed and clean it with alcohol or acetone to make sure its oil free.
2. Print your model with a single layer raft to ensure great adhesion. You can go for a thicker raft if you like.
3. Make sure the print is about half the speed of a PLA print. You can simply turn the knob on the LCD screen during a print to speed up or slow down the print speed which is very useful.
4. Do not change the print speed throughout the print or you will see a very clear line where the filament cools differently. (see our recent tweets)
5. ABS shrinks a LOT as it cools and I had a few models literally split apart as they printed. Its best to make sure you have dense infill (40% and above) and you turn off the extruder fan during a print. Since we do not have a heated chamber what you want to do instead is cool the print as slowly as possible which is why you want the fan off."
I have also found that you need to reduce your print footprint (amount of filament to bed contact) as much as possible. so orientate your print so the smallest side is on the bed. Sometimes this requires more support material but really helps in the end. I have had luck with printing a 6 mm brim as well as having 3 raft layers. My temp has been the standard 235 with fan off.