Cutting leadpipes

[Nomsis]

Some time ago, I wrote about the leadpipe on my Shires Pro Select. I was having problems with response and articulation, and it turned out that the leadpipe had a small crack at the end. I shortened the pipe myself using a simple hacksaw. It wasn't pretty, but the trombone played much better afterward.

In the meantime, I found proper replacements. In fact, I got two used Shires leadpipes. One is a No. 2, which I'm currently using. The other is a 2.5, but I can't get it to fit. Should I use more force?

My main question, though, is about the original leadpipe that had the crack. I'm thinking about having it properly cut. What is the recommended amount by which to shorten a leadpipe?

[baBposaune]

While I don't generally recommend shortening a leadpipe since it was designed to respond a certain way with the original length and venturi, if you must do these experiments the proper tool is a Jeweler's Saw with a fine blade lubricated with Beeswax.

As to your 2.5 which sounds very tight I would try polishing the bottom end with 0000 steel wool, thoroughly cleaning after with soap and water, drying it and then apply a thin tuning slide grease. Don't force it.

[harrisonreed]

How are you expanding the cut end?

[Nomsis]

Thanks for the tips, I will try it.
As the pipe isn't original anyways my plan was to convert it into a proper short type pipe. So if anyone can recommend a length it would be appreciated. So far I cut only a tiny (~0,5cm) bit so the crack was removed.
As for expanding the cut end I don't get why this should be necessary? All the leadpipes are cylindrical at the end AFAIK. I don't plan on cutting the pipe in half.

[baBposaune]

No need to expand the end in this case. Correct.