A warning on pipe-cutters

[wickedbob]

Damn I had the same thing happen to me, I thought the kh tolerances were a bit goofy since I had an 07 post in the new long neck. The seat post now has rings all around it, bare alu from scratching or something. I'll be using a hacksaw from now on.

[john_childs]

Originally Posted by GizmoDuck

For the record, I did file the post after using the pipe cutter. Quite a lot of filing in fact, but obviously not enough.

The pipe cutter causes the bottom to flare outwards due to the pressure from the pipe cutter roller. So it means you can get it into the frame easily enough, but when you try to pull it out, it's like a rachet- it cuts into the seatube and stops you from pulling up.

It's almost welded itself into the frame now. I'm going to take it to the bike shop to use a vice and a blowtorch.

Ouch! I never thought about the possibility of the seatpost getting stuck because of using a pipe cutter to cut it.

I have always used a pipe cutter. Gives an even cut. The one thing I do when using a pipe cutter is to make sure that the roller is on the side that I want to keep. That way most of the mushrooming happens on the side of the pipe that I'm going to throw away. I still need to file some, just not as much.

Good warning though. I'll have to rethink my preference for using a pipe cutter rather than a hack saw.

[GizmoDuck]

Originally Posted by john_childs

Ouch! I never thought about the possibility of the seatpost getting stuck because of using a pipe cutter to cut it.

I have always used a pipe cutter. Gives an even cut. The one thing I do when using a pipe cutter is to make sure that the roller is on the side that I want to keep. That way most of the mushrooming happens on the side of the pipe that I'm going to throw away. I still need to file some, just not as much.

Good warning though. I'll have to rethink my preference for using a pipe cutter rather than a hack saw.

I'm not sure what you mean. The pipe cutter was an industrial one with rollers on both sides.

We spent an hour wrestling with the frame, and heating it up with a paint stripper. We moved it about 2cm, and then gave up.

I'm getting another KH frame. The alternative was to take it to an engineering workshop to see if they can drill out the seatpost, but the problem is that I don't have the time to faff around with that, and also, by the time they charge for labour etc, it probably would just be easier to buy a new one.

I've had a bad day

Ken

p/s if anyone doubts the strength of the KH frame, I can vouch for the welds. We gripped the top of the seatpost in a vice, and basically bashed the $@#! out of the frame for over an hour. We also torqued the fork arms with a very large piece of wood, and wrestled with them until my knuckles turned white.

No sign of any cracks in the welds, or bent fork arms as far as I can tell.

[unicyclist.ca]

maybe i could muscle it out at my house... or give it a good home...

[john_childs]

That would be a bad day.

The pipe cutter I have has rollers on both sides, but there is a trough on one side that allows the metal to mushroom more on one side of the cut than the other.

I'm going to get myself a good saw guide and then hide my pipe cutter.

[GizmoDuck]

Originally Posted by john_childs

That would be a bad day.

The pipe cutter I have has rollers on both sides, but there is a trough on one side that allows the metal to mushroom more on one side of the cut than the other.

I'm going to get myself a good saw guide and then hide my pipe cutter.

I think if you filed it down enough, it might be ok.

But please note that I actually did a lot of filing before sticking it in. And it still managed to weld itself in there.

[adelman]

Originally Posted by GizmoDuck

We spent an hour wrestling with the frame, and heating it up with a paint stripper. We moved it about 2cm, and then gave up.

I wouldn't give up on that frame just yet. Is this one of the frames that allows you access to the seatpost through the bottom of the fork crown? If not, cut the seatpost off the frame, leaving approximately 1" sticking out (for purchase to pull on, later). Then take a raw hacksaw blade and go at the seat post from the interior, cutting a slot in it from the inside outward. If you're patient, you can do this with very minimal damage to the frame. Once the slot is through the seatpost, when you tug on it the circumference will collapse into the blade slot you made and it should come out. If you can access the post through the fork crown, I would concentrate only on the bottom inch or so, since we presume that is where the binding is.

If you do get it out, I'd carefully inspect the frame for any burrs or similar damage that might stick the *next* seatpost. They can easily be cleaned up with a ream, or even a rat-tail file.

[GizmoDuck]

Originally Posted by adelman

I wouldn't give up on that frame just yet. Is this one of the frames that allows you access to the seatpost through the bottom of the fork crown? If not, cut the seatpost off the frame, leaving approximately 1" sticking out (for purchase to pull on, later). Then take a raw hacksaw blade and go at the seat post from the interior, cutting a slot in it from the inside outward. If you're patient, you can do this with very minimal damage to the frame. Once the slot is through the seatpost, when you tug on it the circumference will collapse into the blade slot you made and it should come out. If you can access the post through the fork crown, I would concentrate only on the bottom inch or so, since we presume that is where the binding is.

If you do get it out, I'd carefully inspect the frame for any burrs or similar damage that might stick the *next* seatpost. They can easily be cleaned up with a ream, or even a rat-tail file.

No, it's a frame that is sealed at the bottom.

I don't normally give up easily, but I'm also not silly. Spending several hours on something to just save a few dollars is not worth it. I have no attachment to the frame...because it's new. If it was my Coker frame then that's a different matter altogether. That has sentimental value, and I'd happily file it down with sandpaper before I gave up on it.

It really is depends on whether there are any KH frames in stock.

[lunicycle]

Ken how large was the pipe cutter you were using? From what you say re filing, it sounds like it was too big for the job causing excessive flaring of the metal. The pipe cutter I use can only handle up to 30mm dia, with a narrow cutting wheel - see pic. Haven't had any problems, no need for filing, just a light sand.

Not that it helps much now, but didn't it feel unusually tight when you started to put the seat post in?

[GizmoDuck]

Originally Posted by lunicycle

Ken how large was the pipe cutter you were using? From what you say re filing, it sounds like it was too big for the job causing excessive flaring of the metal. The pipe cutter I use can only handle up to 30mm dia, with a narrow cutting wheel - see pic. Haven't had any problems, no need for filing, just a light sand.

Not that it helps much now, but didn't it feel unusually tight when you started to put the seat post in?

It was about 3 1/2 times bigger than that.

[saskatchewanian]

Originally Posted by saskatchewanian

Sheldon Bown's page 15 Ways To Unstick a Seatpost.

I would really try the CO2, ammonia, and/or the hacksaw blade technique before forking over the cash for a new frame.

I had to use the hacksaw blade technique on an old road bike that I found. It took a long time but it eventually worked.

[unicycledood]

I just hold it and use a hacksaw....

[Chrashing]

Originally Posted by john_childs

....I'm going to get myself a good saw guide and then hide my pipe cutter.

With a hacksaw, I couldn't cut a tube straight if my life depended on it. So I thought that parktool guide was a great idea. But that tool has a minimum size of 1.25 inches (32mm). That's bigger than any seat tube I work with. Darn, and I haven't found another guide.

[Chrashing]

Originally Posted by Chrashing

With a hacksaw, I couldn't cut a tube straight if my life depended on it. So I thought that parktool guide was a great idea. But that tool has a minimum size of 1.25 inches (32mm). That's bigger than any seat tube I work with. Darn, and I haven't found another guide.

OK, found a guide that fits smaller tubes.

[harper]

Ken-

Some options:

1.) Bring it to me. I'll get it out in no time and then we can go out for Thai food. No charge.

2.) Tri-nitro-toluene

3.) Sheldon Brown's hacksaw blade technique. Hacksaw blades in a frame have the teeth oriented to cut on the forward stroke. When using a blade that is not in a hacksaw frame, reverse the teeth so the cut is in the pull direction. Otherwise the blade is like a noodle during the cut stroke. Hold the section of hacksaw blade with vice grips or a c-clamp. Use plenty of light oil or WD-40 to lift the slurry as you cut.