Help. Fans and radiator installation problem obsidian 1000d

how to install a push-pull radiator in the front panel of the obsidian 1000D? what screws should I use?

The thread depends on what brand of radiator you are using, for example EK, XSPC and Magicool use UNC 6-32 thread, while as Alphacool and Watercool use M3 thread.

 

For the bolts connected to the fan tray I'm using 1.5" long button head allen key bolts, however I'm having to space them with a neoprene washer about 2mm thick and 2 small steel washers (about 0.6mm and 0.5mm thick). Maybe 1.25" long bolts might reach. With no washers they seem to take 2mm going through the tray, which might leave 3mm or possibly less to screw in the radiator.

 

For the inside fans I think you'd want them 1.25" long. It is recommended to check if you need to space them with any washers to avoid screwing into the radiator core.

As indicated, it varies a bit based on radiator type. Corsair radiators are 6-32 machine screws as well. The length can be the trickier part. The fan is 25mm (usually), you want it to go 2-3mm into the radiator hole but short of the fins, then there is the case or mounting flange thickness. On cheap cases it’s almost negligible. On more expensive cases it can be a measured quantity. Then there is the question of whether you are using any additional fan dampeners etc. Most people will end up with 28-30mm length. Go longer if needed and use rubber washers to move the screw head off further and keep the tip from piercing the fins.