Floating strut bushing

[ezhitz]

Hi
When using a floating strut bushing how much play is ok. How often should they be replaced.

[grsboats]

I've been using speedmaster bushing for years on my heat boats(nitro/Gas) and honestly never replaced one .....on my Fe models lead teflon bushing.Gill

[rol243]

Gill, why don,t you use the floating bushings in the FE,s ?

[grsboats]

In my opinion floating bushing produce much more drag than lead theflon ones reason I prefer them but this is me.Gill

[rol243]

I thought it would be the opposite , got me thinking now Gill .

[urbs00007]

I thought it would be the opposite , got me thinking now Gill .

how about someone testing both with onboard tachometer?

[grsboats]

John I never did this test but it's easy to see that a pair of lead teflon bushing has less friction area and drag than a floating one.Recently I'm working with ball bearings on the strut of my saw riggers and its clear they are fast than bushing in few miles.Gill

[urbs00007]

John I never did this test but it's easy to see that a pair of lead teflon bushing has less friction area and drag than a floating one.Recently I'm working with ball bearings on the strut of my saw riggers and its clear they are fast than bushing in few miles.Gill

hi gil. the ultimate low drag is straight shaft in precision ball bearings. I used a short piece of flex shaft from the motor to a coupler made from steel, drilled to fit cable from engine to straight shaft on the other end. loctite held the flex, setscrew held the straight shaft. did a gas rigger with 1/4" and rigger with 3/16". driving the gas rigger was almost funny because there was no lag when taking off from a launch, the boat took off instantly. all power from motor to prop is transfered. you should try it. you just have to be able to increase aoa on front sponsons to compensate for negative shaft angle. motor needs to be inline with shaft for no drag. best way to describe it, it's like the boat is running on ball bearings it has such little drag. try it.

[rol243]

urbs, do you have a pic of this set up ? sounds interesting.

[urbs00007]

urbs, do you have a pic of this set up ? sounds interesting.

P1000963.jpgP1000965.jpg first pic shows octura u-joint setup. didnt last, so I built the cable to straightshaft coupler shown in second picture.

[grsboats]

John I'm using piano wire as shaft and my strut has micro bearings instead of bushing,on my gas riggers just a traditional 1/4 flexshaft driveline supported by speedmaster bushing...the last time I had a boat with a u-joint was in the 80's when we used to run FSR monohulls...anyway thanks for sharing.
Gill

[rol243]

urbs, are you using a solid drive shaft on the gas rigger ?

[grsboats]

Looking to your pics I see the ball joint held to the flexcable????? U joint are only allowed to be held to rigid shafts reason you had an issue due to vibration.My very first rigger a Crapshooter .60 had rigid shaft and boat was fast at that time but today I see lot of benefits having an adjustable strut.Gill

[Shooter]

I switched over to the old lead tef pressed in bushings a couple years ago on all my heat boats. No complaints so far. Simple. Limited play and limited drag.

[urbs00007]

Looking to your pics I see the ball joint held to the flexcable????? U joint are only allowed to be held to rigid shafts reason you had an issue due to vibration.My very first rigger a Crapshooter .60 had rigid shaft and boat was fast at that time but today I see lot of benefits having an adjustable strut.Gill

hi gil. the u-joint and the flex shaft to coupler were 2 different ways to connect to a straight shaft.

[urbs00007]

urbs, are you using a solid drive shaft on the gas rigger ?

yes

[rol243]

yes

Piano wire type shaft or solid straight shaft ?

[grsboats]

Thanks John got it.Gill

[urbs00007]

Piano wire type shaft or solid straight shaft ?

solid 1/4" shaft running in precision ball bearings spaced every 4 ". ceramic/stainless hybrids, the bearings were from boca bearings rated to over 50,000 rpm's if I remember correctly. all the motor's power is directed to the prop. puts a smile on your face.