Bad compression tubes

[FPoole]

Might be something in that...



Problem is, my perfectionism shows up with cylinder honing too.. Those flexible hones does not correct out of spec tubes, they just follow existing imperfections.
The only really good way to hone a tube for us amateurs, is to lathe turn a brass rod to fit the comp tube and spin it in the tube covered in fine grinding paste and oil.
It works, but is a bit more tedious than using a flexible cylinder hone.

The brass rod thing won't be accurate either. You need a pin fitting hone. Sunnen makes the good machines here. You can buy a mandrel and use your own lathe, I suppose. I had a TX tube honed on said machine, years ago. The operator sets the thing up for the 1" bore and makes a very few seconds of strokes, to test the pattern before going all the way. Puts a beautiful crosshatch on the cylinder walls just like AA tubes have. My tube was perfect except for some marks where the bear trap notches are cut in. There is also the spot on the inside of most TX tubes opposite the cocking shoe slot, but this is never in the stroke of the seal. As long as the extreme spread for a shot string of 20 or so doesn't exceed 15 fps, I wouldn't worry. A barrel can also make the velocity spread change, so how do you know which it is?

[Shed tuner]

the ABT slot in TX tubes can sometimes cause tight spots in the tubes. Also had a tight spot on a BSA standard, but then that had a massive dent on the outside too.. took some metal off with a file, smoothed with wet n dry, power went up by 2 foot pounds. A brass mandril and some polishing paste is generally a good way to remove tight spots.. bulges are obviously harder work...

[evert]

The brass rod thing won't be accurate either. You need a pin fitting hone. Sunnen makes the good machines here. You can buy a mandrel and use your own lathe, I suppose. I had a TX tube honed on said machine, years ago. The operator sets the thing up for the 1" bore and makes a very few seconds of strokes, to test the pattern before going all the way. Puts a beautiful crosshatch on the cylinder walls just like AA tubes have. My tube was perfect except for some marks where the bear trap notches are cut in. There is also the spot on the inside of most TX tubes opposite the cocking shoe slot, but this is never in the stroke of the seal. As long as the extreme spread for a shot string of 20 or so doesn't exceed 15 fps, I wouldn't worry. A barrel can also make the velocity spread change, so how do you know which it is?

Professional honing tools are obviously the best solution, but they are not available to most of us. Many have access to a lathe, so fitting a brass lapping plug is a more likely option.

Its not only about velocity fluctuations, its about guns that tear up seals, dont make power, leak lubricants past the piston seal and burn up piston seals fast.

[FPoole]

Professional honing tools are obviously the best solution, but they are not available to most of us. Many have access to a lathe, so fitting a brass lapping plug is a more likely option.

Its not only about velocity fluctuations, its about guns that tear up seals, dont make power, leak lubricants past the piston seal and burn up piston seals fast.

Most of our local auto machine shops have the equipment in our area. It was really easy for me because the machinist was a good friend.

[dvd]

Just wondering, will a professional hone machine reach right up to the plugged cylinder bottom without leaving a step?
They are made to hone open ended engine-block bores, no?
Thanks.

[Barryg]

Just wondering, will a professional hone machine reach right up to the plugged cylinder bottom without leaving a step?
They are made to hone open ended engine-block bores, no?
Thanks.

The TX is open ended anyway its not a one piece cylinder like some are.

[evert]

Paul Watts is known for good work, and he uses one, so I guess they do the trick:
https://www.youtube.com/watch?v=OUSJgZQnkC4

I have a gun he tuned and honed the tube on, but dont really want to take it apart.. But I'm curious!