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Good evening fellow pedallers,
I was riding my old hardtail at the weekend being in the mood for retro riding. I'm normally very good at caring for my Kona 7005 Alum frame, but while parked against iron railings, it slipped, and a long and deep 'scratch' was gorged out of one side of my top tube. I say deep meaning I can feel it easily with my fingernail, and estimate it at about slightly under 1mm deep for about a 10cm length.
Because I am not clear on exactly how thick a 7005 frame typically is along the top tube, I'm wondering if I should be concerned? Is this likely to develop weak spots?
If not, I will just carefully spray paint over and forget about it.
GBR
Kona alloy frame...tough as ol' boots.
Needs a pic mate, but sounds nowt.
I'm not sure about tough as old boots! A steel frame yes, but a softer 7005 frame? A pic will not do what I'm describing justice, as it is the DEPTH into the frame I am concerned about. It's dug well beyond the paintwork exposing bare metal.
I'm surprised that such a relativaly gentle tap and scrape against an iron post, scraped so deep and so easily!
(My next frame will be definatly steel!)
GBR.
Put a sticker over it
As I said in my first question, I am not concerned with cosmetic looks (I can respray paint). I am concerned with structure and mechanical fatigue developing..?
Does anyone know how thick such 7005 top tubes are? I can't find any info about them.
GBR.
But a sticker will provide structural strength...
It will be fine.
plenty thick enough... dont panic. be glad its not steel, alu corrosion is self limiting.
"Is this likely to develop weak spots?"
Sorry to say, but who knows? [url= http://www.cycle-frames.com/bicycle-frame-tubing/35-X-610-7005-TOP-TUBE.html ]This one[/url] is 1.3mm thick at the ends, and 0.8mm in the middle
It's likely to be difficult to repair too, a weld could damage the heat treatment for example
🙁
If the scratch really is 1mm I'd say it's a scrapper. I do have a doubt it's actually 1mm though.
Post a pic trying to show the profile of the scratch and I'll cast a professional opinion on it.