Frame drilling disasters?

Had a man interested in a bike I was selling but didn’t like the fact that I had drilled for a dropper.

Cant he do it himself, if he's that bothered?

I (personally) wouldn’t like it either, I wouldn't drill one myself and I wouldn't buy one that had been.

Do I think it would be a problem? Not especially, but I've met plenty of people who consider themselves perfectly reasonable mechanics that I wouldn't trust near a bike frame with a knife and fork, let alone a drill.

I don't think I'd buy a frame that had extra holes drilled in it, just because...

I'd drill one myself, it looks easy enough when I've looked into it. I'd want to inspect it though if I was buying a frame that had been DIY drilled.

I drilled the frame on my commuter bike about three years ago for a Di2 cable to run through. Absolutely no problem with it so far.
I guess it depends on the size and location of the hole.

It might be fine, but the buyer has clearly decided that they want one that hasn't been drilled. No bother, just re-advertise it including that you have drilled it.
Fwiw, I have drilled a few bb's before, no issues. Even spoke to one of the manufacturers and they told me it was fine to drill the bb. Not drilled a seat tube though.

 Absolutely no problem with it so far.

Oh, I've drilled holes into my own frames, it's fine. I just wouldn't buy a 2nd hand frame drilled by somebody else.

just re-advertise it including that you have drilled it.

This. It's possible someone will be more interested in it for exactly that reason.

I don't have a problem with the buyer's decision, I was just interested to hear if one had ever failed.

Had a man interested in a bike I was selling but didn’t like the fact that I had drilled for a dropper.

Cant he do it himself, if he’s that bothered?

Oops, not reading the OP properly fail....

Well no, but people who died when their DIY drilled frame exploded into a ball of firey baby Robin faces don't tend to talk much.

In seriousness though, people will bitch and moan about the manufacturer's poor customer service/production/paint not looking pristine after they rode through a sandstorm etc because its someone else's fault. They're much less likely to shout up and say "oh yeah, I'm a moron, I trashed my prefectly god frame by incompetently drilling a hole in a weld"

Yes, had someone who'd drilled his bottom bracket for drainage (as advised in many locations).

Unfortunately i think he'd hammered the drill bit through the shell, then not put any protection on the bare aluminimum, and used the bike as a daily commuter for two or three years.

The bottom half of the shell corroded away completely.

Drilled two now without issue. I sold the first one a while back and did say I had drilled it and included a picture of the drilling. I was careful to do it well away from the welds. IMO its makes the frame much more usable but I understand that someone else might not want a frame with an extra hole.

I've seen a picture of a seat tube that cracked across a dropper cable hole. It was on a steel custom frame and the hole was put there by the frame builder, not by the owner. I believe the frame builder replaced the tube and repainted the frame as you'd expect.

Ive drilled one, rode it for a few years, didn't die, clearly stated it was done by me when advertised and sold....
can understand why you might be put off by that, but never heard of anyone with a problem.

Maybe it would depend on the frame?

If there was an owners facebook group with tens/hundreds of frames drilled with the same size bit in the same place with no issues then maybe. I'd be wary of something less tried and tested though.

Do I think it would be a problem? Not especially, but I’ve met plenty of people who consider themselves perfectly reasonable mechanics that I wouldn’t trust near a bike frame with a knife and fork, let alone a drill.

Also this.

My brother's bike has a large dent in the downtube near the BB from a rock strike, he can't do anything about it and it's been fine for years afterwards so isn't an issue. I wouldn't buy the bike second hand knowing about the dent but I would ride it currently as I trust that it's ok.

There's a difference between being happy with your own bodge and trusting one by someone else.

I would expect there to be dodgy frames all over eBay if there were DIY disasters

Nah, that's what gumtree and FB are for.

I’d drill one myself, it looks easy enough when I’ve looked into it.

You can't look into it until after you've drilled the hole

Surely a great big heavy battery would cause more potential problems than dropper drilling?

It's the flex in the tube in the area of the hole that causes failures, prob more than what the hole is for / carrying etc. There's a lot of strain in the lower seat tube area and not much on the upper DT area. Metal tubes with holes in certain areas need thicker walls to pass tests than non-holed tubes and it's one reason I dislike internal cable routing in general. I assume you're talking abut a drilled metal frame, not CF 🙂

Unless you've seen stress/strain FEA for the frame under pedal and impact loads I'd be wary of a home-drilled frame tbh. No warranty and a lottery on lifespan. Even brands get guide placements wrong, look at how many Ti frames with internal routing guides have cracked as an example.

No warranty and a lottery on lifespan.

For you or the frame?

^ well if you're clumsy with a drill, both?