I am thinking of having a steel frame built and was wondering what type of steel to use. The 2 types of tubing I have access to are reynolds 853 and 631. What are the major differences in reynolds 853 and 631 tubing? (Weight, durability, maintainence, quality, and so on) Thanks!

the reynolds website will have the information you seek.

Thanks and ps
I am not building the bike myself which would explain my lack of knowledge on this topic!

i'd have it built out of black sabbath myself.

I would head over to the frame builders forum. There is a fountain of information in there.

your best bet is solid iron bars. then you could compete with the Hummers and Suburbans.

To be serious for a moment: I ride an IRO Angus made of 631. I like it, does the trick. 853 is going to be lighter and...that's all I have to say (I don't have any experience with it).

why not consult with the frame maker? Perhaps they would know better than anyone here about the characteristics that would best match you as a rider...

maybe to framebuilding forum will have some input here...

Nothing. 631 is 853 without any heat-treatment. Butting profiles, tube sizes etc are identical otherwise.

What are the benefits of the heat treating?

Heat-treatment raises the yield & ultimate-strength of the tubing. These are the load-points where it takes a permanent set (bent) or breaks completely. Heat-treatment however, doesn't change the modulus or stiffness of the material, it will still deflect the same amount given the same load. It will be able to take a higher load and deflect more before permanent damage

As far as those qualities listed and the differences between 853 and 631, I doubt you'd notice the any difference at all. Fully-optimized frames from each one might result in a slight weight-savings, I'd say about 1/4 lb max.

I don't know why your chosen builder isn't advising you on this. What's next? Will you have to suggest a filler wire and weld sequence too? And why do you only have access to two Reynolds tubes wen there are over a dozen easily available tubesets**********????

Confusement!

He hasn't said he has chosen a builder, just ruled himself out, so far. Also contrary to popular belief framebuilders aren't infalible or consistent in their preferences. Sometimes you have to sort out the validity of what they are saying for yourself. To quote Sy Simms "an educated consumer is our best customer".

Well, if he's not building it himself, I think it's safe to say someone else is, and if he is an 'educated consumer' you'd hope that the person that IS building it would know about such things and be able to advise him over and above some tubemaker company propaganda or a bunch of self proclaimed experts on the Web.

I don't think Sy Simms is advocating consumers that know more about the products than the people selling them!

I think it's cool that the OP has an inquisitive mind and is asking the right questions. However ultimately material choice lies with the builder and sometimes people get into trouble thinking they know more about a material than a guy that works with it every day.

I'm just being devil's advocate.

Yes you are.

Information is power. The more you know the more you can make an informed decision.

In a nut shell, 631 is not heat treated so the tubes are not as thin as 853 which is. The thinner 853 tubes will be lighter but more flexable. Some builders (but not many) balance these two factors - for example, using a larger diameter thin tube in place of a thicker but smaller diameter one. The devils in the details which make the comparison very difficult without knowing which exact tubes are going to be used.