What Size Running Hardware

[Bonehead]

Hello all,

I'm coming to near completion of my Dumas Drag'N Fly 20. Now I need to get the running hardware.

What diameter should I be using for the flex shaft? Should I use .150 or .187 (3/16) size cable?
The original called for a 3/16 solid shaft, so I'm assuming that I should stick with that size for the flex cable.
Also, how do I install the flex shaft though the hull? Do I use a stuffing tube with bushings/needle bearings at the ends? Or do I use a Teflon tube and run that through a stuffing tube? Or just the Teflon liner goes through the bottom of the hull? Too many ways to do this I guess. Any input from anyone who has installed a flex shaft though the bottom of the hull would be very appreciated.

I want to keep this boat as stock as possible with regards to the strut. The original strut was to be mounted underneath the boat forward of the transom. All the strut hardware I've see from other manufactures mount the strut to the transom. There is only enough room to mount the rudder on the transom. I've check out Prather and Octura hardware and they all seem to mount on the transom. Dumas is the only manufacture I've seen that will mount the strut under the boat (it comes up through and attaches between 2 brackets).

Turn Fin?? What size should it be? Lenght I mean. Dumas makes one, but does not show the size. Just wondering what size from other manufactures would work.

Oh, and the engine that I will be using will be an O.S. .15 CV-MX. I know I will need a flywheel for this as well as a collet for the flex shaft. Any idea about who makes a collet for this engine?

Thanks in advance for all your help!

[jetpack]

Hi Bonehead,

I'm gathering what I need for mine. I haven't started anything yet but I've been looking at hardware also.

This hull isn't an easy one to figure out hardware for, but the information I've collected its better to stay with an outboard style strut. It gets the prop out behind the transom more, which helps lift the back of the boat up out of the water for more speed, and allows the prop to surface.

I wanted to go with an underwater strut also, but after thinking about this I am not sure if thats the best way to go, especially with the lack of availability for that kind of strut like you found out.

The transom mounting area on the hull (width) is another handicap. There simply is no room to mount a strut bracket, and another one off to the side for a rudder bracket.

This only leaves one choice really, and thats going with an Octura Strut and Rudder combo, where they are both in-line with each other. This seems fine but what gets me is the strut they offer for those seems too deep. Hydros like shallow prop depths, just like tunnelhulls do. It should allow the prop shaft to be adjusted so the centerline of it can reach the bottom of the hull.

This is just my thinking. I hope someone can stand in and point out what is better for this hull...a submerged prop or a surface prop setup, but I am leaning towards a surface drive setup to get more speed and rpm's out of the motor. This is an area where I am lacking knowlege, and it is a very critical point to the boats entirety.

[charge1(ds)]

www.finedesignrc.com They have some inline strut/rudders that should work well for you. I would stick with the standard rated sizing. As for the setup. Its teflon sleeve in stuffing tube. THrough hull. THe teflon tool acts like a lubricant against the tube and the shaft. As for turn fin. www.mhzusa.com Sells them by size of boat. As for surface piercing or not I am not sure what hardware is made for that must don't specify from what I've looked at. I am getting setup to build a Electric Fountain 25.2" vee mysefl.