correct parts?

[chrisb2e9]

Hi, I am in the process of building a boat from scratch. on my first boat I simply had a drive shaft inside a stuffing box that exited the keel at about a 25 degree angle and was directly connected to the prop. Because of this the prop wasn't exactly 100% effective at moving the boat. What I want to do now is have a motor connected to a flex cable that goes through a stuffing box and then goes through a strut and is then connected to the prop. Again the stuffing box will exit through the keel. I have selected a strut

http://www.rocketcityracing.com/pilot.asp?pg=products&specific=jokrdrr8

and a flex cable

http://www.rocketcityracing.com/pilot.asp?pg=products&specific=jnnogrm8

Not the most expensive parts but i need 2 of each so I am trying to save money.
Heres my question, aside from a prop, a motor and a universal join to connect the motor to the flex cable, what other parts will I need to set this up? I've been looking for days for a good diagram but I cant seam to be able to find one. So if someone could point me to a link where I can find a diagram or explain to me what other parts I will need, I would appreciate it.
for examply, will the prop simly screw onto the drive dog on the flex cable?
or will i have to do something else to attach the prop to the drive dog. I think its called a drive dog anyway, remember I am new to all of this.

One more thing, the flex cable that I am planning on getting is much too long. with these cables are you able to cut them? I cant see it being too much of an issue as the end that I cut will be pushed into the universal joint anyway. I am just worried that it will cause damage to the cable that will get worse over time.
Any information that anyone can provide is more than welcome.

Thank you.

[Rex R]

what size/type motors are you planning to use? if you have a drive dog fitted to the 'hard shaft'(also known as a stub shaft) the sequence/order from the strut is drive dog, prop, some type of prop nut, end of shaft.
cutting;
wrap a piece of tape around the shaft(to cover the area being cut) then fire up your cutter(try to avoid unraveling the cable), remove tape when done, then silver solder the cut end. this (hopefully) keeps the cable from crushing(and generally spoiling your day) inside the coupler and pulling free. hth

[chrisb2e9]

I have a 550 motor right now. problem is that I plan on having 2 so I will need to get a second, but the store where I bought it from cant get any more in.
So I am thinking about getting 2 500 or 600's.
From what you said can I assume that the drive dog and the prop nut are what hold the prop on the stub shaft?

Can the flex cable just run through the stuffing box and the strut on its own or does it need something like this:

http://www.rocketcityracing.com/pilot.asp?pg=products&specific=joiqmph0

to protect it. or is that simpy to reduce friction?

[Rex R]

yes, quite right drive dog & nut hold the prop.
reason I asked bout motors...while that size(dia) should handle anything that a 550 can throw at it, it is also a good bit larger than what is typically used. usually .098" or .130" dia is used for 500-600 motors. er you do know that you shouldn't use counter-rotating props with flex cables right?. think most folks here would suggest that if you need that sort of power then go with a one 700 series motor.
some swear by teflon...while others swear at it, you just have to adjust components to accomidate the extra thickness (or lack of) that the liner takes up.

[n.h.schmidt]

Rex is right.
You don't need anything as large as .187 flex. That is way overkill. .130 is about right for anything you are likely to do .Also ,you don't us a uinversal coupler on flex shaft. A Octura Flex hex or a solid aluminium coupler from Offshore Electrics is what is needed for that. What kind of boat are you going to make? n.h.schmidt

[chrisb2e9]

i've been looking around but I cant find any sites that sell the .130. Is it the same as the 3/16th" in inches?

[n.h.schmidt]

No .187 is 3/16" .130 is just a little over 1/8". Give Offshore Electrics.com a try. They should have what you are looking for. n.h.schmidt

[chrisb2e9]

No .187 is 3/16" .130 is just a little over 1/8". Give Offshore Electrics.com a try. They should have what you are looking for. n.h.schmidt

I thought that I checked that site but I guess I didn't Thanks for the help guys I should be able to take it from here. but if I need any help I'll be sure to come back.

Thanks again

[Ron Olson]

Running 550 can motors you really don't need the 3/16" flex cables. Number one, it's much cheaper and easier to use 1/8" cables and secondly, with those motors you really won't be able to turn over the props that fit the 3/16" shafts.
Avoid twin engines or motors unless they are absolutely needed. Getting either are hard to get an exact match for.

[chrisb2e9]

ok, so I decided to put pics of the boat online. As you can see its small and completly made of balsa wood. So its not exactly that heavy.
I've decided to go with the 1/8 or .130 cable. Since I am having 2 motors what would you guys suggest for a motor/prop combination?
The pics are here:
http://users.eastlink.ca/~chrisb2e9/index.html
I took them by my keyboard so you can tell how big it is.

This also isn't a finished version of the boat. I still have some work to do on it before I finish the hull.