paint cracking?

Andy M-S said:

First off, I have a steel road frame, lugged/brazed construction with
rather fragile paint.

In what sense, fragile?

Quoted message said:

I acquired it new, and have about 1,200 miles
(or so) on it. I weight about 200 pounds.

Today, I noticed a couple of cracks following the bottom sides of the
seatstay/seatlug join.

My LBS suspects it's paint, and I've talked to the fellow who has the
frames built and imported, and he suspects the same thing (but will
supply a replacement frame if I'm concerned).

Why would they suspect it was paint? Are there other cracks like that in
less critical areas? I would be very suspect of such cracks, and would not
believe they were paint only. Scratch away some more paint and see if the
crack continues into the metal.

Can you post a link to a picture?

--

David L. Johnson

__o | Do not worry about your difficulties in mathematics, I can assure
_`\(,_ | you that mine are all greater. -- A. Einstein
(_)/ (_) |

Andy M-S said:

First off, I have a steel road frame, lugged/brazed construction with
rather fragile paint. I acquired it new, and have about 1,200 miles (or
so) on it. I weight about 200 pounds.
Today, I noticed a couple of cracks following the bottom sides of the
seatstay/seatlug join.
My LBS suspects it's paint, and I've talked to the fellow who has the
frames built and imported, and he suspects the same thing (but will
supply a replacement frame if I'm concerned).
Here's the deal. Has anyone else with a conventionally-built frame
(standard seat-lug, not a separate collar) noticed paint cracks in
this vicinity?
I'm just trying to get a sense of what's happening here. Paint chips,
scrapes, etc...that's not a big problem. But if the stays are breaking
away from the lug, *THEN* I'll be concerned...

Could very well be brazing flux that was not properly removed prior to
painting. Some fluxes are glass-like after brazing but will absorb water
slowly and "bloom", destroying paint.

--

Luft could be right but the frame was dipped first? SOP?
Dave scores also.
but frames do flex
flexing may cause some paint's cracking.
there was an ongoing discussion of this some time ago- a year ago?

i ride a six mile section at 20-25 mph(tailwind) over a smooth path
carrying 40 pounds or so on the rear rack with me at 165. I'm
cautious: no ramming.
The paint was rusto dayglo (not recommended-the dayglo as it unglows
or degassses set in a closet)and at the seat stays only at a gross
visual level-dry lake dry mud cracks more or less around an 3/16ths
inch wxl.
i am told natural material's tend to crack in 90 degree angles like
these seat stays.
whereas flux may fall off in a chunk
or metal fatigue wud center around the under flex
not along the bendable length.
[censored]!! get the belt sander!