As i’ve said below, trying to solder a pre-flashed chip isn’t a good idea. Unless you’re quite experienced with SMD rework, you WILL kill your board.
Flashing can be fiddly and it’s very dependent on timing which is quite likely what your issue is. There were, a few years ago, some boards which came without the arduino bootloader and those are not serial flashable from replicatorG. That’s unlikely though so first, check some things:
1. Verify your USB connection really is working - can you connect to the printer from makerbot desktop, replicatorg or whatever host software you’re using? If not, you may have some driver issues that you need to resolve.
2. Verify that your reset button works. Bear in mind it’s recessed quite a lot and you’ll need something that can push it firmly. Pressing the result button successfully (don’t try and flash right now) will reboot the printer, and you’ll see on the LCD that that is happening, so you can verify and satisfy yourself that the reset button works.
If (1) and (2) are good, then you really ought to be able to flash. For me, what worked was to press the button on the PC to start the flash, and then IMMEDIATELY (i.e. within less than a second) press the reset button on the printer.
There isn’t really any feedback to let you know it’s working, apart from the LEDs on the board near the USB port will flicker a lot more than normal. Flash takes probably a minute or so, from memory.
If you really really can’t do it, or if your board really doens’t have the arduino bootloader, there is, of course, another way - that doesn’t involve soldering.
There are two ICSP ports on the mightyboard. One is for programming the 8U2 micro that handles usb comminications (ignore this one) and the other is marked 1280 ISP - that’s for the main microcontroller.
If you get yourself an AVR programmer (e.g. tinyisp, see ebay) then you can plug it in to the ICSP port and then use arduino ide (or avrdude) to flash the arduino bootloader, or you could skip the arduino bootloader and just flash sailfish itself.
Getting an ISP programmer is 1,000 times better an idea than trying to resolder the chip.
