Ultralight Pannier Platforms / Supports

Once components and wheels have been taken care of in the process of transforming a used bicycle into a high-performance tourer, the fun begins.  It's fun to me because it involves a little bit of creativity, and because the results are truly extraordinary.  The fun is in creating an ultralight gear-carrying system.  An incredibly lightweight, ultra-stable system is comprised of two parts, a platform that is rigidly attached to a touring rack and a stuff-sack pannier, which is locked in place and compressed very, very tightly against the platform in a highly secure manner with two or three straps.  The platform of the stuff-sack pannier system functions like the top platform of a touring rack (think of how tightly you can strap gear, length-wise, to the top of a rack with three straps) or the stiffening plate in the rear side of a pannier.  It can be made much narrower than a pannier stiffener as a stuff sack pannier is  much narrower than a pair of panniers.  The first platforms that I made were only a couple of inches wide.  I made them of wood, aluminum and plastic.  One of the first ones was actually just a hunk I cut off of a 60”aluminum ruler (too heavy).  Through the years I've made many different types, including ones of tubular steel and aluminum, and ones of wood ranging from laminated exotic hardwoods to some made out of scrap plywood.  The ones in the photos are of inexpensive  plywood purchased at a hobby-craft store.  Both are very lightweight.  The one on the left is so lightweight (a little less than 2 oz.), and because I mounted it in the way that I did, I used a large but very thin fender washer as a reinforcement at each of the places I connected it to the rack.

A very, very lightweight wooden platform. One of many types that I have experimented with over the past few decades, and a design that requires careful, and very rigid mounting.
Two of the fundamental keys to making wood platforms effective is to seal them from water penetration correctly, and to use a material that is both strong and rigid, yet lightweight.  In long-term use wooden stiffeners cannot get wet.  They must be properly coated.  I've coated them with different types of sealers quite effectively.  They may be painted with a latex enamel-based house paint.  I've used poly urethane sealers and epoxy resins as a protective coating as well.  If I were to use wooden platforms on an around-the-world trip I wouldn't take any shortcuts.  I'd use a very lightweight fiberglass cloth and resin and I'd create extremely rigid, totally impenetrable platforms by fiber-glassing them.  When I coated the ones in the photos I just used several coats of some french polish I'd mixed that day as I happened to be sealing a bunch of custom violin parts that I had just made ( I was curious to see how french polish would hold up in the elements).  In the process of coating wood side platforms I'm careful to seal the edges and the holes for the mounting hardware, especially if they are made of thin plywood like the ones in the photos.  The mounting holes are exceptionally vulnerable in wood.  The best way to make the holes durable and water-tight is to drill a 1/4" hole, seal it with epoxy, and then drill the hole once again with a 3/16" drill bit (or a smaller hole if 6/32 screws are used) so that the epoxy seals the edges of the plywood.

A very rigid wooden platform typical of those that are extremely easy to make, are very lightweight and that are highly effective as part of an extraordinarily inexpensive high-performance gear-carrying system.
In terms of making the platforms function well in a gear-carrying system, it is essential that they be quite rigid, that they are large enough to provide effective support when stuff-sack panniers are compressed against them, and it is important to mount them very solidly.  The platform in the photo to the left is about as wide as I ever make them (3.75 in.) but I make them longer when they are used with longer stuff-sack panniers.  To achieve the most solid mounting of the platforms I use three or four mounting points (always two at the top which are spaced as widely as possible) and I extend the top of the platform up to the top of the rack and square it off as in the platform on the left that is of a trapezoidal shape. 

The rear side of a support. The webbing and fasteners, which locate and fix into position the pannier compression/mounting straps, were firmly attached with epoxy resin.
A very important part of the design of the platforms is the mounting/compression system for the panniers.  To the rear sides of the stiffeners I attach plastic rectangular loops, sewn to 7/16th in. webbing, in which compression straps may pass through.  For home builders the webbing which holds the loops may be first sewn to the loops and then attached to the platforms with epoxy resin (wood or metal platforms) or with Aqua Seal, depending upon the material in which the platforms are made.  The loops keep compression straps from moving up and down and also hold them in place to facilitate mounting the stuff sacks.  It's important to do a good job of attaching the loops and compression straps because they are a very critical part of the mounting system for the stuff sack panniers.  They will ultimately provide the mechanism to stabilize all of your touring gear.