What do you think?

[Don Templeton]

I made these two ball bearing struts some time ago for a center rear sponson non adjustable .12 rigger strut. It gives room for the flex shaft to contract. One is brass and aluminum and the other is S/S. I also brazed a fin on one of the S/S struts so it could be adjustable. I think Glenn used ball bearings on one of his .12s and would like to know your opinions on this set up and especially Glenn's comments.

Thanks

Don :unsure:

 

[Slideblues]

If memory serves me, Glenn Q's were made by Rod G.

Nice work Don !!!

Gene

 

[Ron Olson]

Nice work Don! This might be the trick for squeezing out some more power. I've noticed a little resistance in my Led-Teflon bushings and a setup like this would eliminate that problem.

 

[Kevin_R_Clark]

Very nicely done. But I have a question about contact area and drag from side loading. Would not needle bearings be the way to go?

 

[TimD]

It might pay to oil those bearings every run to prevent them seizing. Looks good tho'!

Tim.

 

[Paul Pachmayer]

Hey Guys,

In FE we've been using bearings in the strut for a long time. Although I don't know much about nitro I would imagine on a .12 size engine your using a .130 or .150 cable so adjustable struts are available done up with bearings from BBY.

As far as trouble with the bearings, I've had no problems with them. Several of my boats are on their 3rd season of racing with the same bearings. I'm also not sure of nitro prop rpm but a couple of my setups are in the 35K range at the prop, 70K at the motor. (gear reduced)

Paul.

 

[Glenn Quarles]

Don, this looks just about the same way I have done mine. On the 12 boat I just use different sizes of brass tube to go from the stuffing box size to the size needed for the bearings (1/4 ID tube for the 1/4 OD bearings). The pieces of tube were soldered together with about a 1/2 inch overlap between the stuffing box and bearing tube, with about 1 inch of the bearing tube behind the stuffing box. On the 12 boat I use two bearings about an inch apart (with a brass tube spacer to keep them apart). I also drill a small hole in front of the front bearing to lube (I use Slick 50) between every run. By putting the lube in front of the front bearing it lubes both the cable and the bearings.

On my latest 21 SAW boat Rod G made me a piece of aluminum that holds the bearings and fits on to the end of the stuffing box.

I have tried needle bearings several time in the past, but have never got them to feel as free as the ball bearings and I have never had a problem with the bearings in either 21 or 12 SAW boats...just make sure to remember to oil the bearings at the end of the day to get the water out!

Glenn

 

[Don Templeton]

Paul: Do the BBY struts use one ball bearing at the rear or two to support the stub shaft? I have seen some before that let the stub shaft front rest in the stuffing box or bushing and I don't like that idea. In mine the shaft never touches any thing but the inner race of the bearings and has about 3/16" clear space before the flex shaft enters the stuffing tube.

Thank's Glenn,

I also made one totally out of aluminum. I made these for a .130 flex shaft with 3/16" ID x 5/16" OD bearings. I started out some years ago using needle bearings in a solid shaft Crapshooter but later changed to these same bearings. Your right, they are much much better and never gave me any problems. I like the idea of the lube hole in front of the bearings. That should work great.

Thanks for all the input guys,

Don

P.S. I use Permatex Sleeve Retainer to attach the flex shaft to the stub shaft. Real neet and clean. (3000 PSI shear strength) Anyone else use this for nitro? I picked that up from an electric forum. What do you guys think?

 

[Mark]

Wow Don, I'm surprised that the permatex holds. What size engines have you tried this with?

 

[Paul Pachmayer]

Hello Guys,

P.S. I use Permatex Sleeve Retainer to attach the flex shaft to the stub shaft. Real neet and clean. (3000 PSI shear strength) Anyone else use this for nitro? I picked that up from an electric forum. What do you guys think?

LMAO! Guess who wrote that artical on building the flex shafts using this method. I've been doing my own flex shafts like this for years without a failure. For example in my Super Sport 45 running a v955 or a x460/3 on a .150 cable I could bring the boat on plane from a dead stop in about 10 feet. It'll hold.

Don, I personally don't use the BBY struts so I can't say but I have my own and converted Hugheys to use bearings. (2)

Paul.

 

[Guest]

Ya Mark, I was very suspecious about joining the shaft that way but I guess a lot of the electric guys over at Rum Runner Racing have been doing this for some time and from what i hear with no problems. Also you don't have to worry about overheating the shaft while soldering. I've done this on my latest .12 but have not tried it yet myself. That's why I brought it up!

Don Templeton