Speed master strut and rudder for Blackjack 26

[fly2mike]

Hi, this is my first post here.
I just recently bought aBJ26 on e-bay as a parts boat.I had planned to use the stock drive gear, but when I saw how broken up the U-joint was I realized it would never do.
I bought the Speed master strut and rudder here at OSE. I have several questions.
(1) I have been reading about strut bushings and how to install the strut, and some of it doesn't make sense to me. The model boats I have built in the past used teflon or nylon thrust washers in front of the drive dog. I was under the impression that the thrust from the prop is transferred to the boat via the strut. If that's not the case then the thrust must go up the flex shaft and applied to the motor shaft to drive the boat forward through the water. This doesn't seem right to me.
(2) It looks to me like the bushing is a nice light press fit into the rear of the strut,(flush with the rear) then the .250 brass tube slides in from the front, (how far?) then the Teflon sleeve slides in to butt up against the forward edge of the bushing, and the heat shrink goes on over the brass tube between the existing stuff box(brass tube) and the new piece protruding from the strut.
(3) I had planned on using the existing hole for the rubber boot/servo linkage for the rudder, but it looks like the rudder will need to be mounted lower and to the right?
(4) I bought the brass bullet nut for the prop shaft. Do need to use a lock nut in front of the brass nut?
So, am I wrong about the strut set up? Does anyone have experience with this type of hardware set up? Can you give me some advice? How critical is the rudder height, prop thrust angle? What about adjustability of the strut? Pictures would be awesome!
I know I will have many other questions in the future, but those are the main ones for right now.
I understand the need for grease.
Oh yeah, and one more question; what does it mean to de-tongue a prop?
Thanks in advance, fly2mike

[fly2mike]

Why have I gotten zero response to my questions?

Maybe I need to limit my questions to one at a time? I figured out the rudder mounting, and the prop question, but I still do not understand how the speedmaster strut can be assembled to work well with a gap between the front of the drive dog and the rear of the strut? Does the stock Black jack motor have a thrust bearing capability for the flex shaft to bear against? The stock outdrive was designed to accept the prop thrust obviously. Do some of the high performance electric motors have thrust bearings built in to the rear shaft bearing? What is the theory behind all this?

[Steven Vaccaro]

I've always left a gap between the drive dog and strut, then let the motor take the thrust or a thrust bearing between the motor and the coupler to take the thrust.

The 1/4 slides all the way into the strut, the speedmaster bushing rides inside the stuffing tube.

The bullet can be used by itself, just make sure its tight. :-)

To de-tongue a prop is to remove part of the tongue.

[fly2mike]

Thanks

Hi Steven, Thanks for your reply! I think I will try running my boat initially with a thrust washer set up in front of the drive dog, just to see how it works.
You mentioned a thrust bearing in between the motor collet and the shaft? How do those mount, and do you sell them on your web site? Do you have a pic of a set up like that?
Another question. Was I supposed to grind a small flat on the prop shaft where the drive dog set screw secures?
I am planning to build a couple of other electric model power boats, so I am really interested in this stuff. I have built two other Dumas kits years ago ( Sk-Daddle too, and a Deep vee 20, both with gas engines) I may try to upload some pics of those.
Thanks very much for your info.
Mike

[Jeff Wohlt]

You REALLY need to leave some space between the dog and strut. You can snap flex shafts if not.

Thrust bearing goes between the flex coupler and the motor. Also, leave a double papers width of space so it is not tight against the motor and coupler.

[Steven Vaccaro]

Sorry I dont have a picture. But Jeff is correct. They are listed on with the couplers. Or you can search for thrust.

A small flat spot will save many problems with the drive dog coming loose.

[Jeff Wohlt]

Here it is

This is a thrust bearing

[fly2mike]

Awesome!

OK, I think I finally get it
I found a good link with some pics. I still need to see exactly how to fit the thrust bearing to the motor shaft, but I get the basic idea. I better order a bearing.

http://www.rcboataholic.com/hardware/thrust%20bearing.htm

Here is a couple of pics of the Black jack and some boats I built years ago. I will remove the thrust washers from the strut, and put a bearing on the motor shaft in front of the flex collet. I still need to balance the prop, etc..

[Rex R]

perhaps not the best shot...steven you may use this if you wish

[Jeff Wohlt]

I have plenty of them if you need one.

And sharpen that prop on the leading edge. Always file the edges facing the hull...convex side.

[fly2mike]

Excellent!

Thanks for the replies.
Jeff, I looked for a thrust bearing on your website, but did not see one, so I ordered one from Steven.
I have a question about the "couple of papers". I can see no perceptible end play on the motor shaft on the Pro boat motor. If the thrust bearing is going to accept the end load before the radial bearing, then does it not need to be a zero clearance fit between the collet and the end bell plate on the motor?
Thanks again, Mike