Aluminium frame + Dremel = How many grams lost?

Discuss light weight issues concerning road bikes & parts.
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by audiojan

audiojan wrote:If you're unlucky you can save 1135g. I wouldn't start chopping it up without understanding structural integrity.

Of course! There is a risk of messing up.
The welds on the frame look well done with generous fillets all round, they are actually quite smooth already, I 'm talking about removing the parts where there are imperfections and clearly excessive amounts of weld - not digging in too deep.
I've done a bit of research on weld smoothing and if done correctly, it can actually strengthen the frame by removing "stress raisers" ... ooth-welds

This thinking is wrong in so many different ways... first, you're assuming the manufacturer did no stress relieving to start with, which is quietly likely not true. Second, you are assuming you can remove material to reduce stress, which again, is not true. Aluminum is a finicky material... done right it can be light and strong, done wrong and it can be light and very brittle... or heavy and brittle for that matter.

Leave your frame alone... if you want a lighter frame, buy one.
"Suddenly the thought struck me; my floor is someone elses ceiling" - Nils Ferlin

by Weenie

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by cadence90

When I was a kid, I wanted to grow up to be a weight weenie.

Now that I'm grown up, I just want to be pragmatic and responsible.

I used to marvel at drilled chainrings, etc. The thought of drilling a frame never once crossed my mind. I think it is a completely crazy idea.
"Gimondi è un eroe umano, che viene sconfitto ma che continua la sua corsa fino a tornare a vincere." - Enrico Ruggeri

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OK, my idea of enlarging the "vent holes" in the head tube is a definite no-no! ... es.105466/

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by mike

do nothing to the frame. keep it as a trainer/travel bike or bad weather bike. you will regret it once you start cutting holes into your frame.

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by victorduraace

Dont do it, needless to say, you will void the warranty.

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by kulivontot

I love how you guys are so concerned about the resale and warranty of a $400 no-name frame. Wreck your frame all you want, just don't sue us for telling you do it.
And when you've given up, PM me, I've got a 52cm NOS 2011 Scott Addict frame I'll sell you.

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by TheKaiser

If it currently has a thick enamel paint job you can save 100g+ by stripping it. Get it anodized rather than repainting it to save the most weight. I'm not quite sure what an average powder coat weighs, but that could be a middle road.

That'll save you a lot more weight than any dremeling. If you were curious to answer your original question you could measure the wall thickness and surface area of the zones you wanted to dremel and sand and get a (very) rough estimate of the total weight loss potential, but I'd say do the paint and call it good.

I've seen pics of Cannondale "smooth welds" being sanded down with a belt sander so I don't know that you were totally off base in your supposition that it could be done safely, but probably just not worth the time/effort.

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by eric01

Ahh brings back memories of "drillium". I heard a couple horror stories of drilling frames too aggressively and some serious accidents. But that was pre internet so all just stories.

I once took a drill to the underside of a plastic saddle when I was a kid. But that's as far as I went.
AX Lightness Vial Evo, Carl Strong Titanium

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by darnellrm

kulivontot wrote:And when you've given up, PM me, I've got a 52cm NOS 2011 Scott Addict frame I'll sell you.

Buy the Addict!! Miles ahead weigh-wise and they are GREAT frames!! If it is an HMX carbon frames, it should be well under 800g from the factory.

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