Homebuilt ROVs Forum

Hi all,
I have purchased the 3 blade 50mm Robbe propellers that Steve and a few others have used to modify their bilge pumps. Problem is that I dont have a lathe etc.
So, does anyone know of a commercially available prop adaptor that will work for these? I would prefer not to have to buy another set of suitable props if possible.

Thanks alot
Mg

I have used this kind. Perhaps you have to use a different dimension:

http://viewitem.eim.ebay.se/40B-mm-Prop ... 96233/item

How do you use these with the Robbe style propellers, as they are "closed" on one end? Do you still use the conical shaped end of the adaptor, or do you just Loctite the propellor to the thread?

To use an adapter like that you would either have to use a prop with a hole completely through it at which point the cone part would then screw on to hold the prop on,

or......

you would remove the cone part and just thread the prop (such as the threaded Robbe's) onto the threaded adapter part. (you should thread a nut on first then the prop and then tighten the nut back against the prop to hold it on so it doesn't come of when the thruster tuns on in reverse. Lock tight will help keep the prop on but with out the nut it will still come off in reverse.

The only problem with those adapters is the 4mm part of the description is referring to the part that slides onto the motor shaft and not the threaded portion. Finding an adapter with a threaded 4mm shaft is the hard part.

-Steve

Yes, that is what I am finding. No 4 mm threads! And, like you said, these style of adapters still need a workaround. Since I do not have the tools, I have just purchased the Traxxas props

I've been looking for a commercial made adapter for years that fit these props but still haven't found one that fits the bill. I looked into getting some of the ones I make manufactured in quantity to sell but I would have had purchase a 100 or more at a time to keep the price reasonable, and I just don't have the money to shell out several hundreds of dollars on something I'm not sure I would be able to sell all of to get a return on the initial investment.

I also thought of making them myself to offer for sale but again for the amount of time it takes to make a few I would have to charge like $10 a piece just to cover my time. The closest work around I found can be seen in THIS THREAD, but you still need a drill press and the right type of vise to make.

-Steve

How much would people be prepared to pay for adapters?

I need to make about 6 so will get a few more made if people wanted them.

I'm using Rule motors as well. A 4mm threaded prop will slip onto the 1/8 Rule shaft. with a set screw on the flat spot they hold perfectly, no adapter required. The problem is that they are small props 1 7/8" is about as big as it gets. Perfect for a Rule 360 as a vertical thrusters, pointless for a 750 or 1100.

What we need is a 1/8 coupler to a 1/4 drive dog with a threaded post, a 3/16 DD would be acceptable as well. As long as the overall length is short 1-1.5" max that would allow for some nice 2.5-3.0" three bladed props or screws if you want to be a nautical d-bag!

I'd buy 6 to 10 for sure!

dont no if this will help but you could thread lock some thread into the prop then screw it onto the adapter, then fit it to your motor.
adam




http://www.ebay.co.uk/itm/3mm-Shaft-Mot ... 337861fbf3