delcrossv

OK , would you like 800 series tubing better? IIRC Specialized uses 6065 for their better frames.
Care to share your favorite tubing?

BTW I like bikes from the 70's.

fietsbob

Anodizing is a layer of partially oxidized aluminum electroplated on aluminum

its a different thing from the corrosion of riding your bike through the winter, on a salted plowed road.

Wilfred Laurier

oh dont get me wrong
i like 531
although i only have one bike made from it
which was made in 1976

if i were shopping for a steel bike today
i would likely get one made from 853
but unless they make a thick walled touring tubeset
i suspect it would be a little too flexy for my liking

please tell me a bike currently being made with 531
and I will retract my snarky comment

fietsbob

The 4 digit number indicates what the alloy composition is ..



My Koga is 7005 . the better chainrings are made of 7075 ... adding T6 indicates a heat treatment process .

2xxx Copper
3xxx Manganese
4xxx Silicon
5xxx Magnesium
6xxx Magnesium and silicon
7xxx Zinc
8xxx Other element
9xxx Unused series

GENERAL ALUMINUM INFORMATION from Aircraft Spruce

4130 is a industry wide designation for a specific Chrome Moly alloy steel ..

numbers on specialty bike tube sets are more their own numbers for various products.

delcrossv

I'd like really like a 900 series bike, but I doubt I could afford one. Can't think of a production bike in 531 offhand,(not that I've looked) but they're selling it for custom makers.

delcrossv

4130.

fietsbob

NOTE: I edited it while you were racing to your gotcha thrill .

what the hell is 900 series ?

Wilfred Laurier

different because gritty salty road spray
clears away the oxide layer
but where the oxide layer is left undisturbed
as on most of the outside of the frame
and all of the inside
the oxide layer arrests further corrosion

as for the abused parts of the frame
ie back of the seat tube
and under the down tube
paint or a powder coat
is your first line of defense

Wilfred Laurier

the new high end stainless tube sets from Reynolds

953 is the super beautiful one
and its slightly poorer cousin
is 921

delcrossv

Apologies.- just innocent teasing. 900 series is stainless.
Polished 953 Mmmmm

fietsbob

OK, know ANSI numbers for that particular stainless steel alloy ?

You seem to use the product numbers from Reynolds catalog.

delcrossv

Just like everyone else.

It's proprietary to Reynolds so I don't have an ANSI number for it. If you can find it, good for you.

It's martensitic, as a hint...

bikeguyinvenice

It depends on what the bike would be used for. For my fast fitness rides I want a light fast responsive bike. If I every buy a bike just for touring I'd want a steel framed bike to smooth out the bumps on the road.

MKahrl

Regardless of frame material if you're looking for a bike for errands or commuting you should consider how easy it will be to mount racks and/or fenders. 1 or 2 hole sets by the rear dropout and at least one set on the front dropouts. More threaded mounting holes higher up the seatstays are handy as well. Fenders need both these holes and generous tire-frame clearances near the brakes.

Some modern bikes can be really ill-suited to mounting racks and fenders on. Sometimes the only answer is a seatpost mounted rack and clip-on fenders of marginal usefulness.

Probably the reason so many forty year old steel bikes are still being used for commuting is they are easy to configure for different uses. And they haven't started rusting yet.

chaadster

Hahaha!

knobster

Yeah, I'd agree with this. Most of these bikes you'll be looking at that are typically marketed as commuters will allow larger tires. Put the largest flat resistant tires you can on it and suddenly frame material won't matter. It'll ride smooth as silk then. Get something that's as versatile as possible and what it's made out of is irrelevant.

Nightshade

There is but one sane choice for a comfortable , long lasting, bike.........steel is real whereas aluminum is great for bike parts & accessories.

cyccommute 

Yes, both metals oxidize but the way in which they oxidize is different. Aluminum is a reactive metal that oxidizes on the surface almost instantaneously. Scratch the metal and a very shallow oxide layer will from in microseconds. The aluminum oxide layer is that is extremely tough. Corundum is one of the forms of aluminum oxide as are rubies and sapphires. On the Mohs hardness scale, corundum is 9 which is one step below diamonds. It's tough stuff and it forms each and every time that you expose new material and it is water insoluble. As an insulator, it keeps electrochemical reactions from happening in the presence of water.

Steel can set up an internal battery where one part of the steel is an anode and the other is a cathode. The corrosion will continue as long as water is in contact with the metal. The water splits into hydrogen and oxygen so that the oxygen can combine with iron atoms which forms iron oxide and free electrons. The free electrons flow to electron poor portions of the piece of steel.

Aluminum and iron can both undergo corrosion in the presence of chloride ions (road salt is just chalk full of them). In aluminum, the chloride combines with the aluminum atoms and makes water soluble aluminum chloride. This keeps the aluminum oxide layer from forming until the source of chloride is exhausted. However iron undergoes a similar formation of iron chloride which is more soluble in water than iron oxide so the iron washes away as well. Chloride can also move along the grain boundaries of steel which moves the reaction further into the body of the metal and enhances water corrosion by opening the structure. The result is called "chloride cracking"

cyccommute 

Anodizing isn't a plating process. It is an oxidation process that is similar to the oxidation that a freshly exposed aluminum surface undergoes naturally. It is just thicker than the natural process. It's also tougher than paint.

Salt will cause some corrosion on aluminum but once it is washed off, the aluminum will naturally oxidize and protect the surface. A steel surface that has been exposed to salt won't be protected by self oxidation.

fietsbob

Uses electricity

cyccommute 

Having made contact of the dangly bits with aluminum bike frames, I can assure you that aluminum is just as "real" as steel.

As for making bike parts out of it, if you are worried about "what you would rather have under your butt at 30 mph", why would you roll on aluminum wheels?

Wilfred Laurier

sometimes theres no point in arguing
considering his sig line states his opinon
that anything that used to be better
will always be better

cyccommute 

So? Just because it uses electricity doesn't mean that it is a plating process. Plating requires a salt dissolved in solution that is reduced to the metal. Chromium plating, for example, uses chromium salts in the bath which are reduced to chromium on the surface of the part. It adds new material to the part. And it is done at the cathode where the chromium salts are reduced in charge to zero (metal)

Anodizing aluminum increases the thickness of the oxidized layer on the aluminum part without adding any material to the part. The process oxidizes some of the bulk material and, as the name says, occurs at the anode where oxidation takes place.

fietsbob

You wrote a PhD thesis on this, link to it.

cyccommute 

No need. This is stuff they teach in high school chemistry. It's fairly easy to understand.