Um, I'm not a sailor, but just wondered if sailors might be able to help with a treehouse problem. I have a pulley and a bucket, so the kids can haul stuff up, but I suspect I need some sort of brake, so they won't lose control of the rope. Would a ratchet block do the job? Any suggestions would be GREATLY appreciated. Everyone I've asked gives me a blank look, and says "pulleys are a lost art."

well... a ratchet block will not stop the line from running free, only slow it a little.

An Oxen block would, but... I think they're ~$150 and that might be over kill for a tree house. You could get a single block with cam cleat.

Something like the H231
http://www.apsltd.com/Tree/d261000/e260621.asp

matched with a triple block would give them some purchase.

Or something like a H187
http://www.apsltd.com/Tree/d261000/e260627.asp

Sadly though, none of these are really cheap options.

A ratchet block would sort of work as a brake, as long as it is running the correct way.

Ratchet blocks tend to work better with more rope wrapped around the wheel part though, more friction between the rope and pulley.

It'd be better than nothing if you need a brake.

Find some guy with an ancient old Hobie 14 or 16 and buy the main blocks off it You could give them a 4:1 pully system with a really nice cleat!

If I were you, I would buy a simple pulley and a horn cleat. You kids will love tying off the the horn cleat and both should be available at your home center for less than 10$ total.

Horn Cleat:

http://www.homedepot.com/webapp/wcs/stor...ocStoreNum=8125

pulley:

http://www.homedepot.com/webapp/wcs/stor...3&langId=-1

I would let the kids figure it out for themselves. Why are you helping with their treehouse?

Because he is a cool Dad who passes on some info while letting them learn some too.
Go Dad!
Second hand boat bit pile. Grab them some stuff. Do the basic, can't kill little sister set up and them let them ramp it up.
Anything with a cam cleat is safest as it can be used quicly and can be trusted.
BUt then a horn cleat should be used to tie off.

I would have guessed that Kellie is a mom.

He? Little sister?

However the cam cleat is a good idea.

I am with Mary on this.
Cam cleats do not control the load. If the load gets away from them, the cam cleat is of no use.
What is traditionally used is some sort of Belaying Post, Dead Man or Snubbing post. That is, a post between you and the pulley and load which you wrap the rope around and the angle of wrap or number of wraps allows you to control the descending load with a light hold on the tail end. Trees come with these, and after fighting to tie off, and untie a load a few times, your kids will have invented this for themselves.

"Ratchet blocks tend to work better with more rope wrapped around the wheel part though, more friction between the rope and pulley"
i don't get that, surely there would be more friction than we have on our mainsheet ratchet blocks? [assuming that the ratchet was at the top and the bucket was being pulled up from the ground]

How about a $19 trailer winch? <img src="http://www.catsailor.com/forums/images/graemlins/ooo.gif" alt="" />