ebrinkman

Hello everyone!

I really love my Surly Big Dummy, but now I'm looking into ways to remove some excess weight. And the deck on the rack is way too overbuilt for my usage as I only load bulky, but light, things on it.

The deck I have is this one, Cargo | Parts and Accessories | Surly Bikes, it's made out of 4mm (5/32") aluminum.

My plan is to replace the deck with four pieces of stock aluminum with a cross section of 3x25mm (1/8x1") connecting the racks, using the racks old screw holes.

Does any one see any problem with this? Surely there isn't any diagonal forces on it? I'm planning a trip to Iceland and don't want this to fail in the middle of nowhere...

I'm not sure if my sketch is just confusing everything or making it clearer, but here it s anyway ;-)
https://s16.postimg.org/n6oga7s4z/P_20150201_190524.jpg

John Lesar

How much weight will this remove? It cant be much.

ebrinkman

It should save somewhere about 1kg (2lbs) when I'm making some quick calculations.

ebrinkman

I think I shouldn't use stock with a simple 3x25 mm cross section but an L or U section instead to increase the strenght.

fietsbob

there are even lighter materials if you look for the aerospace stuff .. Carbon honeycomb Hexcel with Carbon fiber faces.

In Sweden the Baltic birch ply i've found from there, is one of my Favorite materials

Around here the peeler Logs are Mostly Firs.

stripping the Philippine hills of mahogany is making even cheaper Ply sheets s in export markets

2:01

Are the Xtracycle plastic decks any lighter? I have a Flightdeck and seems to be light enough. But either way, say if you're right about the 2lbs. Loaded weight for your trip would be what? 40? 50lbs? Just a drop in the bucket. Take a dump before you go and you've got your 2lbs right there.

ebrinkman

Yes, I could use lighter materials, but I don't find it worth the cost with carbon fiber for this application. Wood would defintly work, but I don't like the idea of the board collecting water even if I use some good coating.

This seem to be the same discussion that they are having in other forums, but there they are taking about 1/10 of this weight. I prefer to both have a light bicycle and taking a dump beforehand


But anyways, I made the rack yesterday! I used U shaped profiles that was 20x10mm (25/32x7/16). The weight saving was 1,0kg (2.2lbs), cost US$ 2.4 and took me two hours to make (spray painting not included).

The pictures shows it after and before.

fietsbob

Lost the seat to carry your Date, but You Knew That.