Mainly for fixed gear mixed urban with really bad roads commute.

If you don't mind the frame weighing a couple of extra pounds, there's nothing wrong with hi-ten. Because hi-ten doesn't have the ultimate tensile strength and yield strength of chromoly and more sophisticated steel alloys, the tubing has to have thicker walls to prevent bending and breaking in use - which means more material - and will therefore be heavier.

All steels from 1010 plain carbon steel to the latest high strength alloys have the virtually the same density (~0.28 pounds per cubic inch), and the same "stiffness", or Young's Modulus (~200 GPa).

tnx for replying. is hi ten the same with pipe steel? if no, whats the dif?

The thing is the strength goal for normal service .. with a Higher Tensile Strength Steel Alloy ,
you need less of it to achieve the needed strength,

with a Lower cost steel alloy You add a Bit More for Safety Margin ,

either achieves the goal of making a functional, in this case, Bike frame.



The Steel Industry uses a Number system to indicate which minerals are combined to get the desired properties of a steel alloy

Thus the 1010 is one mix, and 4130 another ..

https://en.wikipedia.org/wiki/Alloy_steel

tnx bob, so at this day and age, for general all around city usage slight off road, theres nothing wrong bout hi ten steel frames?

Another difference between bicycle tubing and general plumbing pipe is the finishing that it gets before being made into a frame. While the lower cost Hi Ten bike tubing (and some pretty nice 4130 bike tubing) is usually seamed (like generic plumbing tubes are), the after welding the seam finishing is FAR more then plumbing tubes get. So the roundness and evidence of the welded seam is pretty much gone (on the outside). The residual stresses from the seam will be much more "worked out".


All steels are graded/defined with SAE numbers, here's a link to a description https://en.wikipedia.org/wiki/SAE_steel_grades


Remember that these qualities are prior to any actual fabrication (being done on test samples) and after welding, brazing, bending that a bike frame goes through when made. So the real differences between frames of different grades of steel are more about weight, resiliency then strength (as a structure). Some might say that the lower grades of steel (and with their thicker walls) make for a frame with greater ability to survive the test of time. Andy.

I'd say No,

In fact because the Tube wall thickness is Greater It will not dent as easily

when you bump things Or Lock it up.

and if nicked you did not spent much on it.

I like hi tensile steel just fine for the uses the OP describes. My primary commuter is a very basic Bridgestone BB-1 which has a bottom end chrome moly plain gauge main triangle and a hi tensile rear triangle. The frame cost me all of $30 and the parts came out of my parts bin. It is a superb commuter and winter bike.

So, who used 10-20 steel frames, 20-30 , Any 20-40 high ten used? Raleigh was the only one I know that used 20 -30. My old Sekai 2000 used butted Hi ten Tange steel. Any others? Does that make Raleigh's or Sekai's the best non Chro mo frames?

that sounds like marketing designations for tubing to me. More of a subject for the Classic and Vintage forum.

"Best" is a subject for C&V. The designators 1020, 2030, 4130 et cetera are actual information still used today by engineers to choose what materiel to make a gadget out of. So it belongs here.