Question about aluminum

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Hey all, I know it's been like forever, 2 weeks, 3 days, and about an hour and a half since I last visited this forum, but I would like to revisit an old question that we discussed here eons ago. I am wondering about building a Delta Wolf out of aluminum. With the advances that have been made with the aluminum/zinc "welding rods" it looks like it might actually be feasible these days. As I recall, there were A LOT of people back in the day who completely distrusted even the hypothetical idea of it. I have recently watched several videos on YouTube where they torture test the welds and it always ends with the aluminum failing while the "weld" remains in tact. I have even seen some videos where the welder beat the weld with a hammer and severely deformed the 2 pieces of aluminum while the weld remained completely in tact. Watching these videos has rekindled my interest in wanting to build a bike, or 3. I still do not own a welder or even the knowledge of how to use one, nor do I even know anyone who does.
 

Radical Brad

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Welcome back!

Aluminum is a fickle beast. Not only does it suffer something scary called "work hardening", but when it fails it does so completely.
Work hardening happens from constant vibration, essentially making the joint brittle.
Unlike steel, a failure results in full separation and your face on the pavement.

Nothing I make is suitable for aluminum in any way shape or form.
Every frame I have made is designed with flex as a buffer for road vibration.
This makes all of my designs even worse for aluminum.
I warn you not to try. You MUST completely redesign, and know your enemy first.

I would NEVER build anything from aluminum or carbon fibre, and I actually know how.
Not worth it.

Also, if you are worrying about the extra 5 pounds, loose it on your waistline rather than the frame by getting a good workout, which is one of the primary goals of a human powered vehicle anyhow! Dang, I can drop 5 pounds in a day just by cutting back on my salt!

Brad
 
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And you want to start by welding up an alli trike ?

Leave alli to the experts.
I said it has rekindled my interest in wanting to build a bike, or 3, I never said I was about to start. If building one of these bikes is not meant to be for me, then I guess I have no choice in the matter.

EDIT...........thanks for your (cough cough) "support" and words of encouragement.
 
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Twinkle

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No words of support , only good advice , l only know of one former forum member in California who had ( past tense) a alli frame delta , it spent more time in the shop than it did on the road. Having built about 20 machines , with steel we are trying to guide you on the path to a good and reliable trike build.
 
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georgia usa
Although Brad might not be saying what you want to hear it would be irresponsible of him to encourage you to do something he thinks would fail. Same when I asked about carbon fiber I wanted an honest opinion on if it would work not encouragement to do something probably destined to fail.
 

Radical Brad

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I did work as a welder in a fab shop for several years.
I was the guy they gave tough jobs to like cast or aluminum repairs.
I can tell you that welding either is a fool's game when it comes to anything structural.
Once they had me repair a cast crane boom for resale.... yikes!

I am not the kind of person to build anything that will "hold up in most cases".
It's when you least expect it that a 100% failure will come to get you.
The gains to be had with aluminum just don't seem to be worth the risks on a DIY bike frame.

Brad
 
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To the OP, you really would need to be some kind of Wizard to do a build in ally - not for the feint hearted. I'm not into football really, but it's a bit like comparing Sunday league (steel) to Premiership (ally) - no way would you jump from one to the other and expect good results.

I've never done ally welding, doubt I ever will. I'd need a new welding box and different consumables, sourcing materials would be a real pain, then there's all the heat treatment to be done post-weld. The level of difficulty is many times more that good 'ole steel.

Sorry you've taken a bit of a bashing on this one, hope you still do a build on here for us all to enjoy............(y)
 
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