I've been thinking about building a better mousetrap for a camping clothes line for some time. We started with the little coleman reel type that has the nylon string. Didn't like that the string got more and more shredded the more you used it and often would sag to the point your clothes were on the ground.
We looked at some of the ones you can buy to attach to the back of your camper from CW and other stores but many needed a 4" square bumper to mount on or a ladder, neither of which I have. My bumper is flat "C" channel plate steel that basically caps the I-beams frame on both ends and runs the width of the camper.
I'm a big believer in working smart, not hard and wanted something that was quick and easy to setup but sturdy enough that I would not be messing with it during the trip until it's time to pack up.
I saw a couple DIY mods that used the adjustable flag pole mounts for this type of mod or others such as awnings, flags, light poles, etc. and thought those would be the best mounting bases for what I was trying to do.
Next I thought about the poles and initially was going to go with PVC but had some of the adjustable shower rods with the spring tensioners inside. They just twist to make them longer or shorter, whatever you need. They were free and gave me a little flexibility if I wanted to adjust the angle of the flag pole mounts and needed to make the poles longer or shorter based on whats behing the camper at any given campsite.
Had a couple of eyehooks so I screwed those down into the center of the larger end of the pole which had a little plastic insert that acts as a spring stop for the internal spring. Hollow down the center so it worked beautifully and keeps the eyehook shank from wobbling around in the pole.
Next thought was did I want to use clothes line or rope or something else. With those two, you have the often inherent sag and if they are cotten, the chance you will have wet rope to roll up and store in your storage compartment or trailer. I had an old 2 man tent that was ready for the trash can and it had one busted and one working colapsable shock corded pole. I put it together and it was just longer than the width of the camper and gave me about 18" extending through both eyehooks. PERFECT!
It seems much stronger than the rope method would be and should not pull the two rods towards each other like rope would. There is a little sag as those shock corded poles are made to bend slightly but by putting clothes on the outside of the poles as well as the inside, it minimized sag and stayed pretty straight. I tested it with 2 heavy canvas painters drop cloths and a couple wet bath towels I had from morning showers and it did very well.
The main thing as I stated at the beginning is that it is strong and can be assembled and disenbled in about 30 seconds and I won't be tweaking it all weekend every time the wind blows or someone needs to hang some wet, heavy clothes or beach towels up to wind dry. I'll update after we have used it plenty this summer if it don't work out and needs modification.