critterhunter

I've never used a prop saver but saw the need for one on my latest homemade foamie Mustang build. There were no instructions with the GWS prop saver I bought at the local hobby store and, after various web searches, I can find no useful information on how to use the thing. I guess I must be stupid because it must be so easy that nobody bothered to write clear instructions for it. I'm one of those people who prefers not to guess when doing something such as launching my hard sweat and tears onto it's first maiden. I don't want a $2 piece of plastic that I didn't hitch up right to be the cause of a crash.

Sure, I've found some "general" instructions on the net with distant pictures that don't tell you much. Call me crazy but I want a little more than that. I've also got no less than three different versions of how to use one when I asked local people. So, keep in mind I've about had it with my two day GWS prop saver information quest and figured somebody on here might be able to help God's less gifted.

First Question: There were four or five adaptors in the pack. The smallest doesn't seem to want to fit my 3mm shaft. The second size up seems a little loose. Not sure which to use since GWS also had the great idea not to mark the diameter on the stinking things. Which is for 3mm?

2nd Question: Does the first nut to be screwed on have to go all the way down to the bell on my outrunner? I hope not because I need it to clear the nose cone.

3rd Question: Which way does the nut go on? It has a rounded side and a squared off side. The net instructions and pictures of course never made this clear. Hey, why should they...

4th Question: What goes on next? I'm going to guess the prop saver. Which Way does it go on? From the few pictures I can find I'm going to also guess like this "]", where as the motor would be on the left side of that "]" shape.

5th: What goes on next, the other nut or the washer? And, if it is the nut, which way does it go on (rounded end or square end first)?

6th: Is the washer next or are we going to use that? In the various hack job stories I've heard on how to use a GWS prop some mention not even using a washer.

7th: Is it prop time yet?

8th: I've heard some say cut the prop shaft off to where the prop will pop off the shaft on a hard hit. What exactly does that mean? Does the prop just ride on the nut or does it need to seat on the shaft to keep it straight? If there is supposed to be some shaft sticking into the prop then how much?

9th: GWS also had the great idea not to include any O-rings or rubberbands. Which should I use, how many of them, what size, where do I get them, and how do you wrap it around the prop.

Excuse the sarcasism but after dealing with a Tower Pro ESC that had no programming instructions and now this I've just about had it with poor documentation that a lot of RC products seem to come with, if any. I guess they just assume everybody has done it all like them. That's very poor customer relations in my opinion.

jdetray

I've never used the GWS prop savers, but from what I've seen of their instructions, I don't see how they can possibly be effective if used as they describe. For a prop saver to be effective, the shaft can not protrude through the prop!

Here is the first example of a prop saver I ever saw, and it remains a good explanation of the concept:
http://www.rcgroups.com/forums/showt...threadid=20421

The key point is that the prop must be free to swivel off the shaft if it strikes something (such as the ground). If the shaft protrudes into the prop hub, it's the same as if you had no prop saver at all. I think the GWS prop savers will work, but like any prop saver, they must be installed near the end of the shaft. The shaft can be shortened as needed.

- Jeff

Edit:

1. O-rings can be purchased in the plumbing department of a home center such as Lowes or Home Depot. The size of the o-ring depends on the exact nature of your prop saver, the size of the prop's hub, and power of your motor. For a small prop and motor, a 3/4" diameter, 1/16" o-ring may be adequate. More powerful motors need bigger o-rings. I feel prop savers should not be used much above 100 watts, though I know people do it.

Rubber bands also work, by the way.

2. There is another type of prop saver known as a "wobbly adapter." These have the advantage of working with a wider variety of props. You can see some wobbly adapters here:
http://www.allerc.com/index.php?cPath=36_61

Here is a page showing how the wobbly adapters are used:
http://www.allerc.com/ac-propacc.htm

3. It's OK for a little bit of the shaft to protrude into the prop hub. But if the prop won't easily tilt aside when you push on the blades, there is probably too much shaft inside the hub.