DIY luggagerack extension
 

I'm thinking of making a DIY luggagerack extension to put my duffle/drybags on it.

My first option is a plastic/polypropeen cuttingboard and the other option is one made out of wood.

Any thoughts on which material is best etc?

Depends how it's supported.

If it's hanging on it's own weight the plastic/wood may fatigue and break with the bouncing.

Aluminium is the usual material but again if it's bouncing, it will break.

Mild steel is a good material. It has natural flex, is easy to work with and can easily be welded.

Depends what you are good at IMHO:

Wood with proper glue and technique can be fantastic. Go look at old aircraft and be amazed at how light and strong it can be. The trick is lots of ribs and box sections, the skill is getting glue to stick.

If you need bolt together you might want to consider modular shelving or suspended roofing systems. Watch stuff designed for indoor use it often has no corrosion resistance. In a similar vein, steel wiring conduit can be tapped and bent using hand tools. I’d avoid plumbing stuff, they like their copper which is soft.

The breadboard could be strengthened with ribs cut from another superglued down the back?

Be sure to leave one side flat, it'll make cutting bread on it easier. Also, cut a logo in it and you might be able to sell the breadomatic dual purpose rack for a few hundred quid a pop : ROFL

Andy

Cheap plywood
 

To add:
Modern wood glues are stronger than the parent material.

Plywood is a very versatile "engineered" timber product which has much the same properties in both rectilinear directions (just a techo term for you).
There are outdoor specifications for plywood = WBP (water and boil proof) which use the right glue in their manufacture.

It comes in various thicknesses of course; you could try a simple construction of that and cable tie it across your existing luggage rack; this is not my "new" idea - I have seen such contraptions while out on the road.

Lots of detailed and technical info, tnx.

I don't have the skills or facilities to weld so a wooden or plastic rack would be the best solution.

But if i understood correctly, WBP/plywood would be a good option. Even better than a plastic one?

So is the existing rack just too small or is there something else (like a top box) on it taking up the space?

I have a friend who's just done something similar on his KLR650 but at the sides and in aluminium. It did require some reinforcing underneath though. I'd have thought that some waterproof plywood held in place by some (hefty) cable ties - as others have suggested- would be perfect. Get it thick enough (8-10mm) so it'll take a bit of abuse / overloading and drill a few extra holes as strap fixing points. Easy to remove as well by just cutting the cable ties.

The thought of using a plastic chopping board appeals but I wouldn't trust any of the half a dozen or so we have were - too thin, too bendy etc. We've got a nice wooden one that would probably do but if you have to buy something plywood would certainly be cheaper.

Not quite sure what you're aiming for, but maybe this will help.

I made a rack extension on my DR650 a few years ago that worked quite well. I carried a spare rear tire through Turkey and into Central Asia on it.

I built the rack from an old fibergass/wood cross country ski- very strong with a little flex in it. The ideal material, I think and easy to work with. It was u-bolted to the stock Suzuki rack. The idea was to keep the tire on the bottom of my gear, without taking up too much room on my seat, and to keep it from blocking the view of my taillight, not to mention, out of the hot exhaust gases.


http://i831.photobucket.com/albums/z...tivinCZ005.jpg


Here it is in action in Slovenia.

http://i831.photobucket.com/albums/z...lnikSLO023.jpg

............shu

As you outline, timber is easy enough to work, especially if you are not too bothered about the final finish/appearance.

I guess it depends on what plastic you have in mind; plywood is very robust and not especially susceptible to fatigue loads.
Even if it does get damaged through usage, it is easy to replace also.
You may even get spare pieces that are big enough for your purpose from "offcuts" left over from DIY centres or from disposal points/skips.

The occasional times I have seen plywood used, it has been as a simple square shaped "platform" tied onto the top of existing luggage racks.

That's what its for. It's for on top of my existing stock rack and to put (an extra) drybag on.