Headline: a 6x6 gridfinity base similar in capabilities to the ultralight base from DBT85, that can be printed in vase mode with just 7.3g of filament in just under 8 minutes (not counting ~6 minute calibration) on my A1. Without spiral mode, it using 10.7g of filament and takes 11 minutes to print. It is also fairly reliably able to be printed in ludicrous mode, cutting those print times by ~40%. And it can be printed in a stack with PLA and PETG inferfaces: a stack of 10 6x6 grids with ~135g of total filament (PLA+PETG combined) in 2 hours and 34 minutes printing time at standard speed on my A1. All times don't count the ~6 minute standard A1 calibration before a print.

Description:
I really liked the ultralight gridfinity bases of [https://makerworld.com/en/models/1226917-ultralight-gridfinity-bases](https://makerworld.com/en/models/1226917-ultralight-gridfinity-bases) of DBT85, but I found two problems. 1) When printed at higher speeds (ludicrous for instance on my A1), it would sometimes struggle with the overhangs etc. 2) while it printed fast and still worked great with a big 0.8mm nozzle and 0.56mm layer heights (I wanted fast!) printing many of them wasn't fast in practice. There was about 12 minutes of printing, but 6 minutes of bed leveling, nozzle wiping, etc. that happened on the A1 every time, and because they couldn't be stacked, I had to babysit the printer and cool the bed, peel off the grid, and reseat the bed and hit print again every time, which added time and hassle.

After analyzing the gridfinity spec, I realized that really, all the side-to-side lock-in was created by the 2.5mm tall vertical segment that forms the inner curve which the utralight grid creates with it's shells at each corner. 

Here, I've simply discarded everything else. Each grid is a square lattice of 42mm x 42mm cells a variable (I find 0.8mm to be a great balance) thick and 2.5mm tall. Curved pieces in each corner provide the curve that holds the bins in place and prevents them moving side to side. See above for mass/speed. However the major win is the stack, which I include a standard version of in the .3mf file with 0.8mm thick walls on a 6x6 gridfinity grid 10 sheets high. It prints in 2h 40m at standard speed, no babysitting required and uses 135g of filament, or an average of a total (all in, PETG+PLA+purge) of 13.5g of filament and 16 minutes per 6x6 grid.

To compare to the ultralight base, it takes 13.5 minutes to print a 6x6 with the same printer configuration, and uses 9g of filament, but actual print time is just under 20m after including calibration, and one has to babysit the printer. I'll happily trade an extra ~nickel's worth of filament per 6x6 layer for a 20% faster maximum print speed that can be set and forget for nearly 3 hours at a time, hands down. Postprocessing the stack took me about 20-30 minutes to peel off the layers and PETG and clean up the bits of PETG whisps that were clinging to it, but that's probably about as long as I'd've spent handling beds.

I haven't yet optimized all the print settings, and have only tested with the 0.8mm nozzle.