K2 / Proflex Riders Group
General => Tech Forum => Topic started by: will on July 27, 2005, 02:03:05 am
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Interesting experience in the shop got me thinking about extra weight from a powder paint job I got last year.
While trying to strip the white powder coat off the strut on my old 856, I discovered it was roughly 0.1" thick!
Using some rough math, I figured the whole bike frame is about 400 square inches (incl swingarm & strut). This means - if the paint is really 1/10th" - that's about 40 cubic inches of paint!
Now 40 cu inches is roughly 650 cc. So, if this paint is half as dense as water, that's 3/4 of a pound of paint!
I've gotta believe the paint is actually well over a pound because it's nearly as dense as water and there seems to be a lot of paint built up in the cracks.
Time to strip the paint! Then again, I could skip dinner and lose two pounds... :-[
Wow...
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Will.
interesting calculation.
I have an extra weight discovery every morning in the shower. seems this belt of fat appears around my midsection. quite a bit of extra weight! (at least 10 lbs. at this point!)
[smiley=groucho.gif]
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This is absolutely true. Paint weighs a lot and is a major consideration for racing cars and for things like the Forth Bridge in Scotland!
callum
rds
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I concurr,
my back ground is sailing one-off racing yachts. Builders / designers spend alot of time avoiding the weight of paint. All the weight you can save from paint and filler can go into the low part of the keel to make the boat "Stiiffer" (more powerful) for the same overall weight.
As a result they use female moulds for one-off construction race boats (very, very, very expensive) - this minimises the need for fillers on the outside for a smooth, fair hull and they don't paint the inside - just leave bare black carbon. Horrible to live in but you only sleep and eat there so what's the problem!
Sprucey
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Sprucey,
I sail on a kevlar hull boat built by Clarkson's in NZ. Its tan on the inside, so a bit brighter than a carbon boat. Its a 41 ft. Farr-designed IMS boat.
however, at 5'8", I can just about stand up in it. its a bit unusual being kevlar instead of carbon, but it was built at a time when kevlar hulls could be cured at a higher pressure than carbon hulls. Interesting, hun?
also, back in the IOR days I sailed on a 37 footer that the owner had painted red since he figured out that red was the lightest color.
so, paint can be a significant contributor to weight. especially if one is talking about large objects, like boats. however, on a bike, I still think that one's body weight is waaaay more important than the weight of the paint on the bike.
[smiley=groucho.gif]
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Non-racing boats are classic repositories of tons of paint. We used to joke on my first ship (Keel laid in 1935) that the paint was the only thing holding it together. The joke wasn't really that funny in 1985!
Anyhow, I checked that paint density. It's slightly more than water; it sinks!
So... there's about 2 pounds of paint on my old 856! (That's 1/7th stone, right [smiley=evil.gif]??)
Sprucey, don't know how you can tolerate conditions on those stripped down racers. One sailor to another, that's a hard ride!
Cheers guys, it's back to the paint stripper!
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What the #@*&!!(&^&&&^?
2 lbs. of PAINT? Where did you go for that PowderCoat job? Seriously, that is a lot of paint.
Reminds me of Cannondales. Kids ask why they grind the welds down. The first impression is to lose weight.
Terry
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i think you guys are sniffing to many paint fumes.....Whilst paint is heavy (pick up a 250 or 500ml can of paint,,,,i just cant beleive there is that much paint on a bike...
Will review your figures here........
I think maybe you missed out a zero somewhere,.A tenth of an inch is 2.54 mm!!!!That means the paint has increased the diameter of the tubes by 5mm!