Hi,
I’ve built 2 cereal dry boxes for my non-AMS A1 printer where I can print directly from the box with a bowden connector.
I’m just wondering if it’ll be a good idea to install a vacuum connector to remove the air from the box ? …less air then less humidity
…by using a pump like that ?
I think you’ll find those cereal bins have seals that are far from hermetic and any vacuum you put them under will quickly leak back to ambient. I wouldn’t bother. Get a filament dryer and dry before printing. Use the drybox to feed the filament so it stays dry while you’re printing.
Store it so that humidity isn’t totally uncontrolled, but otherwise forget about it.
Even if the seal is initially good enough to limit air exchange, creating a vacuum will collapse the container and probably pop the lid off when it distorts.
IP67 won’t do it. That’s a rating for only 3 foot water depth. You add 0.445PSI for every foot. So the equivalent vacuum pressure it’d be good for wouldn’t even be 2PSI lower than atmospheric. If you draw a decent vacuum, the pressure inside is going to be 10LBs or so lower than the pressure outside. Quite a bit bigger a pressure differential. The air might even make a whistling sound as it rushes back in. 
IP rated container is not a bad idea, though. I think you’d want something with an IP68 rating and a manufacturer’s spec saying it was good for at least a 10PSI (> about a 20ft depth) pressure delta.
While this may seem like a good idea, it is only really a great way to waste time and money. If you want the TL;DR version, one needs heat to get the water to escape. While less air may reduce the amount of moisture, as @RocketSled has noted, there isn’t enough of a seal to maintain a vacuum.
Here are some real world comparisons for using a vacuum chamber compared to a food dehydrator for drying filament.
That slide came from CNC Kitchen who performed real tests. If you want to see his video on the subject of vacuum drying, Here’s the full video that may help you decide.
Thanks guys for the replies!
Just bought a Polydryer so after transferring to my existing dry box; I thought why not removing some unwanted air… 
