I wanted to play with milling machines, lathes and TIG torches; but college steered me toward playing with words and images instead. There's a space in my shop where a Bridgeport will probably never sit. =sigh=

6000 Vs. 7000 Alum. Frame,,,
 

So What Is The Difference In My 6000 Series Frame And A 7000 Series Frame?

1,000.

Rather than plagiarize this site's chart, I'll just give you the link:

http://www.brucescycleworks.com/tips/tip18.html

(BTW, he misused the phrase 'begs the question' :D)

100% of the conflicts with him would be avoided, if sombody were to choke him out. I'm not an advocate of this type of behavior, I'm just pointing out a fact.

Don't get rid of Hank, I find him funny.

Your deep-rooted feelings of inadequacy would end if someone were to make you sleep with the fishes. I'm not an advocate of this type of behavior, I'm just pointing out a fact.

I would first need to have a feeling of inadequacy, for this to be a fact.
BTW, Pete, have you found a therapist to help with your Narcissism?

I had a job for 12 years where I "played" with and old bridgeport mill,an old lathe(kompf I think),MIG,TIG, stick welding and trouble shooting.Lots of fab work as well. Now I swing a hammer building multi-million dollar custom homes. I've been lucky to have jobs I really like. I love the fact that I learn something every day. You should get that mill you would love it. I have learned a lot about differnt metals and welding over the years but I don't feel qualified to give my opinion on frame building.:o

Bi Ti. Bicycle Ticycle. You'll never regret it.

6000 series is alloyed primarily with Magnesium and Silicon. Usual range of strengths are in the range of 300MPa yield. 7000 series is primarily alloyed with Zinc, Magnesium, Silicon and Copper. Usual range of strengths are 480-550MPa yield.

6000 is tougher, and far easier to weld. However both need proper heat-treatment after welding to restore strength to the weld zone.

Either the mods should lock this thread down like they with others Hank has been involved with or lock him out. The mods on this forum are inconsistent. There is no reason we all should be derailed by Hank's foolish behavior. It is contrary to of the DISRUPTION portion of this forum's guidelines. Why have rule if they are not followed?

I suspect Hank Rearden has contributed more to this thread than most are aware of.

If you can't handle the hardship of reading carefully, typing carefully, and thinking critically, there are two other easy options you may choose: 1) Don't get emotionally involved with an internet discussion board or 2) use the ignore button.

As Hank would say, not true (without presenting any facts to back myself up).

It isn't a matter of handling anything. If the mods don't control Hank or me, I and others have alternative forums to be involved with. No emotions at all. If I can't get some worthy discussion regarding frame material on this forum (I should), I know I can elsewhere, and I willl. I persume the mods of this forum would like good discussion regarding frame material and not have it disrupted and degrading into pissing matches. That is why the disruption clause is in the guidelines.

BTW, the ignore button makes swiss cheese out of a three page thread if I were to ignore Hank.

The best and most detailed series of articles on the topic
 

http://www.bohemianbicycles.com/materials%20science.htm


I wouldn't really talk about this subject before reading that series of articles.

I've seen that one around a number of places. It's an excellent, and not too impenetrable approach to materials for most cyclists. Some of its a little sensationalist, and a few statements aren't quite right, but otherwise, I liked it the first time I read it.

So scandium makes the welds stronger, as strong as the alloy frame material.
However, isn't it also put in the frame alloy as well? If so, what is the point of being in the frame material and not just in the welds?

Here is what Salsa has on their website:

With Scandium tubing, frame engineers are able to use smaller diameter tubes, thinner cross sections, and shaped tubes to tune the ride characteristics of each frame while using less material.
Scandium frame tubing also has increased fatigue life and improved failure modes when compared to traditional aluminum frame tubing

Yes, it is. The reason is simple. You do not weld stainless steel with mild steel filler wire, and if you want a homogeneous bike frame, you do not weld a tube with a disimilar filler. This is exactly the reason I am unhappy with Reynolds' approach to 953. They have made that mistake, and it demonstrates they don't know what they're doing.
In the case of Sc alloyed aluminium alloys, you add Sc to the tube to ensure there's no weld-pool dilution of the alloyed filler wire with parent metal, to below the point it has any effect. You don't alloy the tube for the tube's sake, you alloy it for the weld's sake.


And that's just bullshot. It's about as metallurgically sound as the 'welding non-"thermophilic" steels weakens them'.

Here's a cool quote from that website:
I never knew this.

This has been a interesting discussion. If you feel that Hank is trolling then just don't answer. You must feed a troll for him to be involved. I did not say that I thought Hank was trolling I just gave a way to deal with it. I think that Hank gets very involved in his hobbies and learns as much info on the different aspects of that hobbie as he can. Yes,he does use that to push buttons sometimes but a lot of it is misunderstanding. I could be totally wrong on this but it sounds good.

For those of you who don't not understand that metals deform by dislocation glide, please skip to the last paragraph :)

The fun bit about fatigue is that is is intrinsically linked to crystallographic orientation. Perfect metals - those with a face-centred-cubic crystal structure and the maximum possible slip modes do not have a fatigue life due to the ease with whihc you can deform them: It doen't matter what defomation vector or combination of vectors are applied, they will continue to platically deform until the materil runs out of dislocations.

Hexagonal metals, and body-centred cubic metals have a defined fatigue life because below certain dislocation glide stresses, the dislocations present within the metal will not budge. Either they are locked by having a limited number of directions they can move through the metallic lattice or insufficient stress to activate them has been applied.

Hexagonal metals have limited dislocation directions, but low activation stresses, body-centred-cubic metals have high activation stresses below certain temperatures, and limited dislocation directions. As an aside, this is what makes ferritic steels brittle at cryogenic temperatures.

Skip to: Magnesium also has a fatigue life, no matter what that article says. It's hexagonal, with a high c/a ratio. It's just a very low stress limit fatigue life.

Thanks Falanx - brilliant comments!

Once again, great information.
How about Gunnar frames with OS2 butted tube sets, featuring True Temper OX Platinum air-hardening steel alloys? I believe they used to use 953?
Falanx- what do you think is the best material for a mountain bike frame over the long haul?

I have always preferred cromoly frames, until I purchased a Cannondale with a 7005 aluminum frame.

I rode that bike into the ground, and never had a problem with it. It survived through numerous crashes and wrecks, constant bashing, and large drops.

My new bike has a 7005 aluminum frame, and I feel perfectly confident in it.