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potential rust inside steel frame(16 posts)

potential rust inside steel frameRob Margolies
Sep 25, 2001 5:29 AM
I was cleaning my Bianchi a couple of days after riding in the rain, and I noticed rust around the small holes at the end of the chain and seat stays. I believe these holes are to allow the hot steam and gas to exit the frame when it is being TIG welded. What is the potential for water getting inside the frame? Should these holes be plugged or just squirt some WD-40 inside. Thanks in advance
don't plug them!!!!alex the engineer
Sep 25, 2001 6:51 AM
If you do, any moisture inside will remain there forever! Also, unless you also plug the stem, seat tube, steerer, etc, you will be only plugging the exit for that moisture.
WD40 will likely end up in the BB, and will dilute the grease there, causing bearing failure. Even cartridge bearings are not truly "sealed".
If you ride in the rain alot, then buy a can of framesaver. Tear the bike down to the frame. Squirt it in the little holes when you do the entire frame. If not, then just keep it in a dry place and don't worry about it. The MgMo steel of better frames (even cheaper CrMo) doesn't rust too quickly. Aluminum oxidizes even slower.
addendum:alex the engineer
Sep 25, 2001 6:55 AM
If you are worried that water is getting in the holes, try to find some little hoses to fit in the holes, about 1" long. It may look stupid, but that should keep the water from getting in, while also allowing air through.
ridiculousnm
Sep 25, 2001 11:43 AM
nm
Bogus Advicegrzy
Sep 25, 2001 1:28 PM
There's a product out there called "Frame Saver" that is highly advised for just this purpose.

Alex - what kind of engineer are you anyways? I find that you've been handing out some very dubious advice lately - and I'm not alone in my thoughts.
says who?alex the engineer
Sep 26, 2001 5:15 AM
I was the first to suggest using framesaver, so THAT isn't bogus. Do you suggest that plugging holes is the correct thing to do? Do you do that to your own bike? If you do, then you are an @$$.
As for the small tubing idea, it was just that-an idea! Several years ago, while working in the repair shop of a Merceded Benz dealer, I noticed that Mercedes autos used just such a system on their rocker sills. The idea was to keep water out, while allowing air in. Small surgical tubing probably would accomplish the same thing. Have I actually done this? No. I'm not that worried about frame corrosion. Could it work? Sure it can.
If you have any problems with any advice I give, please be specific about just what you wish to challenge, rather than resorting to ad hominems.
Megrzy
Sep 26, 2001 11:01 AM
You qualified using "framesaver only if you ride in the rain a lot". I didn't catch that you were refereing to the actual product Frame Saver, vice some generic home brew using WD-40. You don't need to ride in the rain a lot to get rust. I guess we all have to make assumptions about what you meand/don't mean since you can't seem to make it clear on your own. funny - I just thought you didn't know....

The use "eustation tubes" on all sorts of things, particularly boats as well as cars. Problem isn't mass quantities of liquid water entering, but rather water vapor (a gas) and associated condensation on unproteced bare steel. Something that is different on a car which is painted all over. Tubes won't address this problem one wit. This is probably why I said your "idea" was bogus. You could also keep a pressurized bottle of clean dry nitrogen to purge through the tubes leading into the holes, but this would be pretty dumb ass also. I don't think you spend enough time thinking about the real world before you reply.

Holes need to be there - it would be pretty stupid to plug them. Why do this? Even carbon bikes have them - to let the water out.
rightjacques
Sep 27, 2001 5:05 AM
grzy is right. Most of the rust formed inside the frame tubes is generated by condensation. This is made worse by air conditioned storage. Every time a bike is moved from a cool, dry air-conditioned room to the hot, humid outside, water forms on the inside of the tubes.
says who?Nessism
Sep 27, 2001 5:57 PM
Lots of frames are vented with a hole/slot in the bottombracket shell. If vented this way I don't think there is much reason for the small holes in the stays. The holes are there to vent the tube during brazing and don't serve much purpose otherwise.

For rust proofing I use a product available at Nissan car dealerships called "Rust Preventative". This material is designed to be applied to raw steel and does a good job of protecting the metal from corrosion.
ways to prevent rustDog
Sep 28, 2001 5:37 AM
*Pack the entire frame with grease
*Have the frame chrome plated, inside and out
*Have the entire frame sealed with helium gas inside
*Ride only in desert climates
*Replace it before it can rust
*Have the frame made from stainless steel, or better yet, aluminum, carbon, or titanium

BTW, I've never heard of WD40 getting inside the bb and destroying it. Seems like that would take a whole lot of WD40. I've used it in my 1980 Bianchi, and the bb is as smooth as new, no rust, either (but I live in the desert).

:-)

Doug
Negativegrzy
Sep 28, 2001 8:53 AM
Holes are in the stays to let the water out formed from condensation. You've got to get all of the "dead legs" or this is where you'll have problems. If they weren't really necessary after brazing they'd be plugged. Even the stays on a carbon bike have holes and they don't rust nor are they brazed.
Negative - NOTNessism
Sep 28, 2001 7:58 PM
If you want I can send you a fax of the pages in my Paterek Framebuilders manual where it instructs the builder to drill these holes for brazing vents.

I would imagine that even a carbon frame would benifit from venting during the assembly process for the same reasons as a steel frame - to allow heated air inside the tubes to excape. I also could imagine that some framebuilders would not fill these to allow some frame venting. A vent hole in the bottombracket is a better idea however since this is the low point on the frame and water tends to collect here if it slips past the seatpost.

As a side note the Independent Fabrications Crown Jewel touts the virtues of their "Fully sealed tubeset to protect against the elements". Imagine that.
why worry?jacques
Sep 29, 2001 3:01 PM
Just curious - does anyone keep a bike for so long any more that inside frame rust actually becomes a problem? The mere suspicion of rust eating away at my frame while I sleep used to keep me awake at night, but when I stopped to think about it, I sold every one of my "this is the last bike I'll ever buy" bikes long before the frame rusted through.
I agreenee Spoke Wrench
Sep 29, 2001 7:05 PM
I put rust worries in the same catagory with "You can have a damaged frame tube replaced if you have a lugged steel bike."
I have a 1980 BianchiDog
Oct 1, 2001 5:42 AM
Bought a Columbus steel Bianchi in 1980. No rust (well, some very, itsey bitsey spots), but keep it touched up and oiled inside. 21 years; yup, it could have rusted.

Doug
Negative - NOTgrzy
Oct 1, 2001 8:44 AM
Oh yeah - whole lot of heat getting applied to carbon frames in an autoclave.

Problem is where's the low point on the rear upper stays and fork and how does the H2O get to the BB? Why don't more manufacturers put drain holes in the BB area.

Ultimately frame builders will continue to push their art for a variety of reasons - some technical and some asthetic. Kind of interesting that you have one reference saying holes should be drilled, then close with reference to IF where holes aren't drilled. Which is "correct?"

Why aren't the holes closed after the brazing process - they're no longer needed. why are they even put in a composite frame?