Hey guys,
I recently was given a reynolds ouzo pro 1" full carbon fork, but stupidly cut the steerer down using a pipe cutter I used a saw blade for the very last bit as I couldn't get the pipe cutter to go all the way through and I tightened the cutter very slowly. How likely is it that the fork has sustained internal damage at the steerer? Should I not risk riding it? are there any tell tale signs that the steerer is toast? there aren't any visible cracks on the outside but when i stick my finger down the 1" steerer I can feel small vertical lines running down 1-1.5cm - I think caused by the saw blade flaying the inside somewhat.

Help would be greatly appreciated.
P.S - this is for a steel road bike build using a vintage 4130 crmo frame.

So, now you know. You cut CF forks with a fine hacksaw, or coping saw. Use light pressure and fast strokes. Then finish the end with sandpaper wrapped around a block.

Meanwhile, not seeing the damage or having any idea how hard you cranked the tube cutter I can's speculate on the condition of the fork.

I wouldn't have gotten into your situation, but if I were, I'd clean up the end find an expansion plug which supports the end and put it together and ride. Then keep an eye on it by removing the plug from time to time (no need to loosen the stem), and look inside with a bright light.

Another option would be to bond in a thin steel tube then fit a star nut below the base of the stem, and catch it with a long top cap bolt. One brand of fork (Cervelo, maybe?) uses this system, and the thinking is the steel tube buttresses the fork a bit, plus can act as a safety net of the CF fails. The safety net consideration is why I suggest pushing the star nut (only with a steel liner) below the stem, so the top bolt is anchored to below any likely break.

Thanks mate. I'm quite paranoid when it comes to CF so I'm thinking I might just stick with steel forks, will be about 350-400g heavier but at least i'll have peace of mind.

Sorry about the fork, but I wouldn't toss it. You may want to revisit using it sometime later.

For future reference, tubing cutters are for plumbers. When bike mechanics need to cut something, the right tool is a hacksaw fitted with an appropriate blade.

There are homemade hacks, but a cutting guide is useful as well. Park makes one.

Post a photo of the cut area(looking down into the steerer tube).

The fraying you described is common after drilling CF tubes(like when mounting bottle bosses/cable stops). If it's not very deep into the tube's thickness, you might be okay. Steerer tubes are quite thick compared to the main frame tubes.

FTR, a diamond blade chop saw is best for cutting steerer tubes, but most people get acceptable results with a fine toothed hacksaw.

Don't have permission too

Hold on one tick actually

ok, so here are the pics --

https://ibb.co/g776mQ

https://ibb.co/meykfk

https://ibb.co/jwQy0k

https://ibb.co/cEUDY5

I took the fork into a bike shop and they said apart from the fraying/poorer cut it shouldnt be an issue to use. The guy said I can file the inside of the steerer to get it nice and smooth to allow for a plug to fit nicer. However I wasn't too sure how credible these guys were because he was talking of star nuts :S Speaking of the plug, I also took the plug that I got with the forks (second hand NOS) and the guys told me they're for handlebar ends and not steerer tubes. I did mention that when fitted they are nice and snug and they do tighten the whole headset but I don't know now :S what do you guys think?

https://ibb.co/dCWhRQ

I wouldn't hesitate to use that fork. the cut isn't great, but the fraying isn't a big deal. DO NOT use a file on the fork, but a little fine(320 grit) sandpaper should clean it up as needed.

I would buy a new expanding plug though.

^ +1. There's nothing wrong with that fork.

And if you used a pipe cutter with the wheeled cutting blades ( the way it was designed to be used) you probably didn't put much crushing force on the tube anyway.

Pipe cutters don't cut. The wheel flows metal out of the way in a wedging action similar to how the bow of a boat pushes water to the side. It takes a fair amount of concentrate force to keep the wheel from simply climbing out, which is why we see the large burr left over when tubing is cut.

However CF doesn't flow that well, so you get a fracturing process. It's OK early in the process when the material is thick enough to support the work zone, but as you reach the end, the force delaminates the inner layers, compromising the structure.

I agree that this fork may be OK if the fracturing is limited to the zone that will be supported by the stem and expansion plug anyway. However, if the delamination spreads to about 2" beyond the cut, the fork will be compromised in the critical zone below the stem.

So, it's up to the OP to make his own judgement about the extent of damage he caused(or seek an expert opinion), but the takeaway is that pipe cutters are the wrong tool for the job.

Yeah - I realise the wrong tool was used and kinda bummed by it should've done my research before doing what I thought would work.

With regards to the pipe cutter, yest it's a type that has the circular roller and two other roller/guides on the other end. I didn't cut all the way through, I used a saw for the final cuts to get all the way through, which I think could have caused the fraying on the inside. I used a little super glue along where I made cuts and also a little inside the steerer tube, but will use a fine grit sandpaper tomorrow to smooth out the insides.

The bike store guys told me the fork is fine and as there are no visible cracks on the surface it should be fairly stable but I'm just so paranoid of a catastrophic failure. I use the bike for commuting and can't afford to have it snap/crash on me.

Also the plug I got was the one the guy gave to me and he said it would work, was he right? I can't seem to find any compression plugs online for a 1" carbon steerer... they seem quite rare.

FSA Compressor 1" Black Expander Plug > Components > Headsets > Star Nuts & Compression Plugs | Jenson USA

Here's a link to a bunch of plugs. If yours looks similar to these, it's correct. However, you may wish to buy one of the longer plugs which extend deeper and will help buttress the steerer. The fork may not need it, but it will add to your peace of mind.

I wouldn't sand the inside, because there's nothing to be gained, so the only potential is to worsen the issue (not that it will).

Just use some nail polish or similar to seal the end of the tube after you've cleaned it up with fine sandpaper.

FBinNY, didn't Reynolds use a glued in plug on some models back then?

I remember seeing a company that included a piece that was glued in after the cut was made.

Yes, a few companies did, which is why I referenced it in my first post. I guessed based on vague memory that it might have been Cervelo, but Reynolds and Alpha Q are more likely possibilities.

There are also long plugs of a similar design that are split and expand, the the OP will find them among the types pictured in the link I provided.

The longitudinal fibers on the inside surface of the fork may have been torn loose. That happened to me on an old seat post I cut that way just to see what would happen. I smeared a little epoxy over the inside surface and it is fine.

I'd ride it. Get a plug that has better coverage. I like the enve plug: Enve Compression Plug Steerer Tube Expander.

I rode with a cracked carbon steerer tube before and it's really apparent when the crack gets to be an issue. It'll creak whenever you put pressure on it. It occurred whenever I climbed and would stand up and put some pressure on my bar.

noodle soup's recommendation for a plug is good. And are you saying you Googled "1" fork compression plug" and didn't find anything. I get a whole page of them.

Ok so i know you can get 1" comp plugs, the bike store even had some. Issue is that most kf them are for aluminium steerers which have a bigger center hole and after trying a couple they didn't seem to fit into the hole of the reynolds fork. So I'm looking for something made specifically for a 1" carbon steerer.

The guy at the lbs told me that if I'm paranoid I can just keep checking on the steerer by removing the top cap/stem and if it doesn't get worse then it'll be fine.

If you are really worried about it being damaged, throw it away and start with a new fork. I wouldn't worry about it though.

You aren't making sense. Expander plugs aren't used in aluminum steerers, only carbon. If it is for 1" steerer, it should fit.

Hmm ok none of the ones I've seen so far seem to fit :S

Some of them may arrive partly expanded. You have to back off the expansion bolt, and sometimes massage the expanding section smaller again before fitting it.