Is your Lubuntu computer a laptop? Is your friends IDE a 3.5 inch HDD? If so, I think the problem here may be that your USB connectors cannot provide enough power to spin the drive for extended times. I had this problem when I was trying to spin a 2.5 inch on a Raspberry Pi (not good...not...good). Here are some solutions that may help if this is the problem (which is what it looks like):
- Try on a Desktop Machine - Desktop machines provide much more amperage through their usb ports. They are almost always capable of spinning 3.5 HDDs.
- Save as much power as you can - Darken your screen, unplug other devices, turn off wifi and blutooth, and pray to God that you have enough power to spin the drive on your laptop. You may also look at
powertop. This measures power usage from multiple devices and can disable/change certain devices' power consumption.
- Try on another laptop - It may be your machines is just too efficient when it comes to power production. Another laptop may have better luck.
This is about all you can do. I would bet 95% that the problem you are experiencing IS power related. Your system can spin the disk for a bit, but after too much speed, the system cuts off connection to the USB to preserve the core system components. After the amperage builds up again, it allows connection again. This is why you would experience disconnecting/reconnecting happening, especially with large file or large system scans.