Bad Drive = ~300GB
Image Drive = ~1TB
Final destination Drive = ~300GB (identical to bad drive in size)

I set the bad drive up side down, put a huge 400CFM centrifugal fan on top of it to keep it cool. ddrescue'd the data to an image on the image drive. I had zero errors for the process (blew me away as I tried dd before, without fan cooling or flipping the drive over and I had errors in the copy, only recovered a small amount of data).

Now I've removed the bad drive, ddrescue'd the Image file to the Final destination drive, but I'm getting errors. I don't understand what the problem is. The 1TB is brand new (few months old but hardly used or powered on). The data cable and power cable are a tight fit on this drive and I was thinking that might be a problem. I had issues detecting the drive after swapping the new destination drive in and removing the old source. I unplugged and adjusted the serial and power cables and got the drive to be recognized and got the data to copy.

It had some errors here and there until 50G when it just crapped out and claimed the remaining 250G had bad blocks.

None of this was reported before when copying from original bad drive to the image drive.

Suggestions? Ideas?

It's splitting failed sectors now and could take forever. So if this is a cable connection issue I'd like to resolve it.