Wisdom needed here!
My lovely 4 year-old Inbred,which looks like this:
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has got some rust at the end of the gussets on the top tube and down tube.
This is what it looks like after I've sanded it and treated it with Q-rust.
Down tube:
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Top tube:
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Should I be worried about the rust I can't see underneath the gussets or is it likely to be just superficial stuff with no significant implications for structural integrity? I'd love an excuse to get a new one but I can't bring myself to replace a perfectly good frame.
I wouldnt worry about it fella, if there was any major rust under the gussets they'd be warped and pushed up/out of shape.If I were you id warm it up with a hair dryer to dry any moisture out then put a bit of car body filler in any open seems and wack on 2 or 3 coats of paint to keep moisture out, job done!
If you've not waxed it already, maybe try seeing if you can poke a needle or similar into and under the gusset, it could help give an indication of how far advanced the rust is? If it is at all advanced that is.
If you can't poke about at all it's probably okay.
Tim
Thanks guys. I've tried sticking a Stanley knife into it (while I was paring off the paint, not just for fun) and couldn't get in. Guess it'll be OK.
I'd be a bit concerned by the pitting on the down tube, tbh.
It will be the death of the frame eventually, the rust has pitted the metal significantly - if you had it 'blasted' it would more than likely go through. You will proably get years out of it yet though.
fastindain - no no no! Body filler is not designed to go over open seams, it will crack and mositure will get in. 'Seam sealer' is what you need, it remains felxible and is designed for the job. The amount of cars I see where filler has been used over unwelded seams - shocking, they always rust out. Sadly for you, thelegsdontwork, the horse has laready bolted so to speak. www.peterflynnclassiccars.com
If you had some boutique type frame, then I guess ther would be some mileage in getting the frame blasted and repainting, sealing the horrible gusset gaps but................
You mean I'll have to have a new one? Oh dear, oh dear.
if thats a brazed joint which i'd assume it is then there are two structural issues - inadequate penetration (ooh err missus) and probably linked as looks like poor workmanship flux hasn't been cleaned off after doing a bad job of the brazing and this has caused the corrosion
i'm not a frame builder or a welding/physical metallurgist (production metallurgist by qualification with some experience of looking at material failures)
but my a little knowledge is a dangerous thing says that frame sucks and probably shouldn't have got out the door
would be interested in a frame makers opinion and yes i'm aware on one has an excellent reputation and good products so i guess this was possibly just a friday afternoon error or user abuse and i'm prepared to be corrected
User abuse???? Moi?
If it was me I'd asked, I'd wonder if it was because I had it powdercoated a couple of years ago and the new paint covered over the gap, trapping moisture inside.
I'm sure that's just how they were finished, certainly the onone's I've seen have been finished with the seam left open. Some seam sealer prior to painting would have taken seconds to apply and cost pence, would have prevented that.
I think they are welded not brazed - far too labour intensive for a frame of that price.
It looks ok to me.
The gussets are left open ended to prevent stress risers i imagine. If you welded the end over then you'd just get a huge build up of stress in that area, which would make the gusset completely pointless