BM1397 registers here :
https://github.com/GPTechinno/bm1397-rs

also the Saleae application Logic has a BM1397 extension that can be loaded from within the app

i think the "sanding" is to flatten the prior solder remains, when retrofitting the mono heatsinks, then termal paste is used for isolation

here is esp32s3 rust hal if You have not seen it already
https://github.com/esp-rs/esp-hal/tree/main/esp32s3-hal

myself is targeting rp2040 = pico and are using "embassy" that has great async using a task executor,
https://github.com/embassy-rs/embassy
"embassy" has some esp32 in pipeline as i understand is "work in progress"
https://github.com/embassy-rs/embassy/issues/745

the BM1937 chips to PCB are soldered with  ≈ 183C melt-point and heat-sink to chip is using ≈ 130C in repair manuals from bitmain.

We would need make a design or 3 -and draw it / test print

-i see a bottom base plate with a 0.8 * 0.8 * depth(?) indentation.

-and a lid where PCB-breakout is mounted, the lid could have a overhang with sides when placed over base, the overhang-sides could have m3 machine screw adjustments ? if the 3d-print could not be made exact, the threads for the adjustment-screws would be made after print.

-no hinges for lid ? , but weight of lid could maybe be sufficient make contact ? or the overhang sides of lid could almost meet the base where magnets could pull.

well any design that works will float my boat ...

then maybe a esp32 with display to drive some test confirming chip is operational

also if somebody here is handy with 3d-printing ? well even answer if it could be done with a 3d-print.

i am looking at a BM1397 PCB breakout
https://www.pcbway.com/project/shareproject/Socket_BM1397.html

and if a pressure mount 3d-printed holder for the bm1397-pcb could be made for testing chips without soldering.

RE:
"Once the design settles down a bit, we'll do an at cost group buy of assembled PCBs so people can start hacking on them. Stay tuned!
Finding a reliable (and affordable) supplier of BM1397AG for this is on the to-do list!"

hi,

regarding recycling BM1397 chips, there is a "lot" for sale of "need repair" s17+ (65 chips per hashboard * 3 hashboards per machine) in Dallas.

If somebody is local and can inspect corrosion of the hashboards maybe we could do a group buy . i can take 10 machines myself (600 in lot).

when sourcing BM1397 AD AG AH AI now they are on offer for 15-27$ each as new and around 6.5$ each as used, need ship from China.

the chips are sorted in production into bin numbers, a hashboard has a label of version(AG AH AI) and bin of chip + a Line number of hashboard, bin numbers are allocated on errors in frequency testing and Line number after assembly testing of hashboard.

so it is best have matching "bin" of chips in a assembled Bitaxe, (bin is not labeled on chip but after in sorting, but can in case of recycle from hashboards be deducted from label.)

i am thinking bid 20USD per machine for all with pickup on site in Dallas, today's price for a s17+ would be around 150-250usd depending connection for a working machine, these are in need of repair and for them its scrap and if somebody take all We could probably bid at 20 ok say 21.

guesstimate 33% of chips not working, would leave about 130 chips to be saved per machine.

if we can not buy the lot of 600 maybe we could give an offer of x machines at price y, count me in for 10.

but first need understand if dampness in farm has corroded the machines so we need a inspection, and after sort out logistics.