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Used a pipe-cutter on a seat post, now the cut end is flared. Tool to fix this?

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Used a pipe-cutter on a seat post, now the cut end is flared. Tool to fix this?

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Old 11-19-14 | 11:24 AM
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Used a pipe-cutter on a seat post, now the cut end is flared. Tool to fix this?

Noob problem: I used a small pipe-cutter to shorten a seat post, and the cut end is now flared enough that it will not fit in the seat tube.

1. Is there a tool I can buy that will fix this, while giving the cut end a smoother edge?

2. Is a hacksaw the correct DIY tool for this job? (short of using an expensive power tool)

Thanks
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Old 11-19-14 | 11:26 AM
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number 1... A File.
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Old 11-19-14 | 11:37 AM
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A file will remove the flare.....A hacksaw will cut without a flare.
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Old 11-19-14 | 11:45 AM
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Thanks guys. I thought the flare might be too wide for a file and didn't attempt it. I will tonight.
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Old 11-19-14 | 12:46 PM
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Or a sanding block (piece of wood & sandpaper)
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Old 11-19-14 | 07:29 PM
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A fine tooth hacksaw is OK for cutting a seatpost. You can use a hose clamp as a guide for a straight cut.
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Old 11-19-14 | 07:44 PM
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Originally Posted by Reynolds
A fine tooth hacksaw is OK for cutting a seatpost. You can use a hose clamp as a guide for a straight cut.
Right. The main issue with a hacksaw is that without a technique for ensuring a straight cut, you are likely not to get one.
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Old 11-19-14 | 08:17 PM
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Straightness doesn't matter too much for a seatpost. Steerer tubes should be pretty close to straight.
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Old 11-19-14 | 08:18 PM
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Originally Posted by JanMM
Right. The main issue with a hacksaw is that without a technique for ensuring a straight cut, you are likely not to get one.
Unlike a steerer, the bottom of a seat post doesn't have to be cut at exactly a right angle so cutting it by eye is adequate. A perfectly straight cut may be desirable for your own satisfaction but the seat post will work just fine without it.

To the OP: A file will do a good job of removing the flair and, in fact, you should continue to file until you form an inward bevel at the cut end. That will make installing the seat post even easier.
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Old 11-19-14 | 08:38 PM
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Originally Posted by HillRider
Unlike a steerer, the bottom of a seat post doesn't have to be cut at exactly a right angle so cutting it by eye is adequate. A perfectly straight cut may be desirable for your own satisfaction but the seat post will work just fine without it.

To the OP: A file will do a good job of removing the flair and, in fact, you should continue to file until you form an inward bevel at the cut end. That will make installing the seat post even easier.
Absolutely correct that a funky cut would not affect a seat post but it would bother many people no end. More of a real (mostly aesthetic) issue with a handlebar end than the bottom of a seat post.
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Old 11-19-14 | 08:43 PM
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Originally Posted by JanMM
Absolutely correct that a funky cut would not affect a seat post but it would bother many people no end. More of a real (mostly aesthetic) issue with a handlebar end than the bottom of a seat post.
Yeah, no question a straight cut is more satisfying even if nobody but the owner knows it's there. I use a steerer cutting guide to shorten seat posts and would certainly use one to shorten a handlebar but neither application absolutely requires it.
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Old 11-20-14 | 06:34 AM
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You can use one or two worm-drive hose clamp(s) as a saw guide; I use two as protection in case the saw jumps out of the slot. I clean up the cut edge with a belt/disc sander and clean up the ID (unnecessary but OCD-compliant) with a rat-tail file.
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Old 11-20-14 | 09:09 AM
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At one shop, we used this -- the other side had blades on the inside of the cone and would fit around the outside of tubing:




Current shop, we use one of these de-burring tools:




At home, I just use a file.
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