Geeetech i3 Pro B and shorter heat break

[peter887]

I've been attempting to service one of the aforementioned Geeetech printers for a friend and I'm running into an issue I'm hoping someone has encountered and dealt with before, given it seems like the kind of thing that's likely to present itself.

From factory, these printers ship with a 38mm PTFE-lined heat break. Or, rather, they should - turns out this specific unit lacked the tube entirely, which is why it wasn't working (I at least was able to remedy that). I had already ordered a replacement bi-metal break, since I figured it would be less maintenance in the long run and that's going to be of benefit to the user. Said bi-metal break is only 26mm long, however, which represents a problem.

If you've not used one of these printers before you might think you could just lower the Z stop and all would be well. I know that's what I thought. Turns out, at least without modification, that the longer break is required to get the tip of the nozzle to extend past the plate the whole hot end/extruder assembly mounts on. So lowering the stop is all well and good, but that plate is going to touch the bed well before the nozzle does. As such I need to find a reliable way to drop the whole assembly and/or shave some off the bottom of the carriage, such that an extra ~10mm of travel is made available.

Is there anyone who's encountered and solved this particular problem already?