I have an old IBL ball screw. I took it apart to repack it and one of the 3 returns is in sad shape.

It looks like it's melted on the outside and there is a hump on the inside.

I've never repacked a ball screw before so I don't know how much of an issue this is.

IBL (International Ballscrews Limited) were bought by Danaher (who also owned Thomson) and were known for a while as Thomson-IBL. It's not clear to me if there is a current connection with ThomsonLinear. I asked ThomsonLinear and they basically said we need to see a company website before we'll talk to you.

One option that occurred to me is to just grind out the hump with a micro dremel bit and try and reinforce the back side with some kind of filler.

I sent an email to ablservicesltd.com (UK) as their page says "A B Linear was born of the demise of Thompson IBL and therefore has an ingrained understanding of the product with over 20 years within their manufacturing team. A B Linear has an extensive stock of Thompson IBL ballscrews and parts and can carry out prompt and timely repairs for all Thompson IBL ball screws." We shall see. They may only do mail in repairs and this is something I feel I can just fix myself with new returns.

Again, this is the first time I've ever taken a ball nut/screw apart so I'm learning. If something above is idiotic on my part, apologies :-)