RND props

**Duane Scarborough** · 03-26-2009, 11:12 PM

Hi all,

I've just got off of the phone with Robin Blankenship of RND props in Blakely, Ga. He seems like a nice guy, and seems to know what he's talking about, but does not have any experience with a 4A084 application.

Has anyone here had any experience with him or his props?

Thanks,

Duane

**Wildfowl** · 03-27-2009, 10:09 AM

Good morning Duane, Ahhhhhaaaa….the best part of waking up is….waking up.

Hope someone has had some direct contact with Robin. If not you can find some folks on the SA forum who have. Just go to the forum and in the upperish, rightish, corner there is a magnifying glass/search button. Click on that and type in rnd in the top search field. You will get a few research-and-development posts but also quite a few about RND Propellers. All of the summaries were positive. There you will find a link to a video of a mini running the RND.

I always wondered about the small propeller manufacturers. Had a bad accident next door with a home made prop in the late 60’s. A couple of guys built one and tested it in the door of their shop and it spun real fine. Took it out to the river, launched, fired it up, and on the first full throttle push the prop blew apart. For the sake of young eyes let’s just say that day was a tragedy.

You will never-ever find me, a friend, or a loved one standing in line with a spinning prop. Never Ever !

Anyway after doing some research and learning how wood props are made I have a lot of confidence in them. All my props are wood with the exception of one tractor I pulled off an abandonded Corvair project. I sure do like the benefits of the new carbon fiber and would lean that way myself. Than again there are some that will say for your motor go wood.

The props I have seen are made on a wood replication machine. Kind of like a giant vertical key cutter. You can see the process here(lower left corner) : http://www.culverprops.com/culverintro.php

I am kind of a fan of metal leading edges. I have never owned a prop that didn’t have something fly into it…but than again I have well over a thousand hours running time.

Good luck with the links.

imported_Papee · 03-27-2009, 12:19 PM

Robin is a good guy, I have dealt with him before. With that said, in our lower horse power applications, each small prop adjustment makes a noticeable difference. Each prop manufacturer makes his own shape/style prop. This difference would make the same size and pitch prop perform different on the same motor under the same conditions.

What I am saying is that each manufacturer has to test these props in each of these situations to get the right match for a prop. A formula will get you close but without testing there is no sure way to test the match of the prop to the motor.

If I were making a choice in a fixed pitch prop I would go with a proven prop for my specific application. You may find that a prop that is made using a formula and untested for your application may not be the most efficient prop.

I have tested many different props on my different engine setup from wooden props to two or three blade adjustable carbon fiber props. If you want a bolt on prop getting the best results, go with one that has been used before on your engine setup.

This is only my opinion, other user opinions may vary.

In short, if you are on a budget, talk to others that are running the same setup and see what they are using. This will save you the cost of experimenting with prop configurations. Some of us are low budget, but I fall in the no budget category.

**Wildfowl** · 03-27-2009, 03:32 PM

Sound advice for a limited budget! Very sound!

Wait...does sound advice belong on the noise page? :P

**Duane Scarborough** · 03-27-2009, 05:42 PM

Good advice all. Robin admitted that he had no experience with the 4A084. But he was pretty informative. He even went so far as to suggest that I consider going with an Arrow Prop, since that's who built the reduction drive.

Thanks,

Duane