What is a whiffle tree?

[mn_308]

I bumped into this photo/video pictorial and thought it was informative (newb that I am…)

I’m confused on Page 7, what is that?

[dimurrrw]

I think I can answer your question, at least as it would apply to page 7. Look at the page again. Notice the block of metal with the threaded rod going through it. As the rod turns, the block of metal moves up and down it's length, like a nut on a bolt. Look at the picture one more time. Notice the two wire cables on the opposite side of the block of metal from where the the threaded rod enters. They are attached to adjustment bolts, which also run through the block of metal. The nuts on the cable adjustment bolts (look at the picture again) are turned, usually while the cable is not under load, until the cables are equally tensioned. Then, as the block of metal moves along the threaded rod, which is turned by a motor or crank, EQUAL pull is exerted on each cable. As with all things mechanical, keeping such a mechanism clean and lubricated ensures proper operation.

A common use for such an arrangement, in the realm of camping, would be to raise the top on a pop-up. The cables which transmit the lifting force to the four corners of the top must apply equal force to each corner simulantiously. Otherwise the lifting mechanism would bind. Gravity takes care of the return trip. Pulleys are also involved in this specific application, but that is another discussion.

[mn_308]

Richard,

Thanks for the response.
That explains and makes sense.

I saw that and started thinking 'WHAT? Another item I need to check and maintain?"...didn't understand it from the description, function, or location.

Once again, demonstrating my newb-ness to TT ownership.

Thanks again!

[flagstaff]

mn308 Don't feel bad about being new and not knowing what a wiffle tree was. After 30 years it's the first I've heard it called that. I did know I didn't have one anymore though.