I think Wiki's a bit off on the metal densities. This chart: http://www.simetric.co.uk/si_metals.htm
says brass is on the order of 10% heavier than stainless steel. That would make sense, as both copper and zinc (the two elements that make up most of brass) have higher atomic numbers and atomic weights than iron. This page: http://www.onlinemetals.com/brassguide.cfm shows yield strengths for brass around 50-60,000 psi, stronger for a given thickness than 304 stainless steel (31,000 psi) or 6061T6 aluminum (40,000 psi), but weaker than 316SS (60,000 psi) or 7075 aluminum (73,000 psi). IIRC the heat-treated 'super steels' used for lightweight bike frames (like the Reynolds 753 in my Riv's) are up around 120,000 psi - strong stuff! I don't know about fatigue life, but depending on the alloy used brass fenders should be as strong as stainless ones (Berthoud, VO), but a bit heavier. Aluminum fenders (Honjo, VO) have the advantage of being able to be twice as thick as steel or brass ones, which should make them both lighter and stronger. Aluminum fatigues, though, so Al fenders should probably be mounted to minimize flexing due to vibration. I know there are wooden fenders out there. Does anyone make titanium fenders? Carbon fiber/kevlar/Spectra composite? Bill On Jan 14, 7:13 pm, benzzoy <benz...@yahoo.com> wrote: > On Jan 14, 3:56 pm, PATRICK MOORE <bertin...@gmail.com> wrote: > > > I'm no metalurgist: how sturdy -- ie, resistant to dents and to permanent > > bending -- is brass compared to aluminum? The alum fenders I own are very > > stiff and dent resistant. > > It depends on how thick they make the fender. According to the chart > provided on wikipedia.org(1), brass deforms more easily than 2014-T6 > aluminum. However, I doubt the Honjo fenders are made of such a high > strength aluminum alloy. They are probably made from a lower strength > alloy that shouldn't be that different to brass in term of yield > strength. > > > I suppose that brass would be closer in weight to steel than to aluminum? > > The density of brass is about midway between aluminum and steel; it's > actually closest to titanium: > > Al = 2.7 g/cm^3 > Ti = 4.5 g/cm^3 > Brass = 5.3 g/cm^3 > Steel = 7.8 g/cm^3 > > (1)http://en.wikipedia.org/wiki/Tensile_strength --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To post to this group, send email to rbw-owners-bunch@googlegroups.com To unsubscribe from this group, send email to rbw-owners-bunch+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en -~----------~----~----~----~------~----~------~--~---
