Revolt 30 - bushing question - 1st post!

[martin]

With less of the stub shaft in the bushing it possibly could cause the shaft to tip in the bushing loading it up more.

[4mulafastech]

With less of the stub shaft in the bushing it possibly could cause the shaft to tip in the bushing loading it up more.

That makes sense.

[steveo]

Maybe try leaving a very small gap just enough where u know the bushing flange would still be seated in the strut I am assuming 2mm . I can only think that the flange has exited the strut and the lip is forced against the strut edge not allowing it to spin as the force drive dog holds it there causing friction. Ose has a replacement strut bushing with tighter tolerance maybe look into that as well

[tlandauer]

That may be the reason that the solid part is shorter and the winding is deeper/closer to the floating bushing. I understand the problem, I think the stuffing tube is not long enough all the way to give the entire length support for the bushing, on top of that you have manufacturing sloppiness so when the collar backs out you have wobble. On the SpeedMaster we typically run the stuffing tube the entire length of the strut bore and when you insert the bushing , the collar is stopped by the stuffing tube outside ( at least that is what I have come to understand and done on my builds) , the wobble is detectable but I would think it should be less than the amount you described.

[4mulafastech]

Thanks guys. I took a few more measurements and pictures. The first pic shows the how far the stuffing tube is from the back of the strut (5.5mm) and the second pic shows the bushing pushed all the way in.

In the third pic I slid the bushing out and put a little side load on the collar with my finger and tried pushing it back in the strut. The sharp edge of the collar would catch the inside edge of the strut. There is enough play since the bushing is pretty far out of the stuffing tube and with the loose tolerance. I'm not sure, but I think the longer prop shaft of the stock flex cable may help a bit in preventing this situation. I am also going to slightly chamfer the sharp edge of the collar so it is less likely to catch the inside edge of the strut and definitely look into the bushings offered here on OSE.

[tlandauer]

Length of the shaft and also the exact measurement of the diameter of the shafts. Could be the up-grade shaft is just a hair tighter in the bushing and it turns the bushing more along with the spiral winding direction of the cable which is "pushing" towards the drive dog. The spiral ( when turned counter-clockwise) is like a screw, it pushes liquid back, thus pushing the bushing out. This may be very insignificant but in theory I think it is possible. I grease my cable that way: I turn counter-clockwise so the grease comes back down when I see excessive grease coming out the stuffing tube at the collet end.
Seems to me that since your collar can go all the way into the bore, can you "extend " the collar by cutting a short piece of brass tube and slide it over in front of the collar? that way you can still have the "mandatory" gap and when the bushing slides out there is that extra collar to "center" the bushing.
Just difficult to find a brass tube that will fit inside the bore yet slide over the bushing. I don't know what measurement AC uses, seems a piece of 1/4" K&S tube with just 2 mm length would do.
Had a long week, please excuse the

[siberianhusky]

My solution to this exact problem was to change over to Octura lead/teflon 1/4 od bushings. Trimmed the stuffing tube slightly, too some measurements to see how far into the strut the stub shaft goes, drilled the strut out to that depth with a 1/4" bit on a drillpress. Pressed in the bushings and away I went. Took about 15 minutes to do this mod. If you were very careful you could do it with a hand drill more than likely. A small drill press is super handy in this hobby, mine in the basement shop is just a small home depot cheapie.

[4mulafastech]

Length of the shaft and also the exact measurement of the diameter of the shafts. Could be the up-grade shaft is just a hair tighter in the bushing and it turns the bushing more along with the spiral winding direction of the cable which is "pushing" towards the drive dog. The spiral ( when turned counter-clockwise) is like a screw, it pushes liquid back, thus pushing the bushing out. This may be very insignificant but in theory I think it is possible. I grease my cable that way: I turn counter-clockwise so the grease comes back down when I see excessive grease coming out the stuffing tube at the collet end.
Seems to me that since your collar can go all the way into the bore, can you "extend " the collar by cutting a short piece of brass tube and slide it over in front of the collar? that way you can still have the "mandatory" gap and when the bushing slides out there is that extra collar to "center" the bushing.
Just difficult to find a brass tube that will fit inside the bore yet slide over the bushing. I don't know what measurement AC uses, seems a piece of 1/4" K&S tube with just 2 mm length would do.
Had a long week, please excuse the

No need to appologize, all of that definitely makes sense! I ordered a spare flex cable from Kinetic Racing which (from the pictures) looks like it has the same length prop shaft as stock. At this point with the stock flex and this bushing there are no need for modifications and I am very happy with the performance. I am going to look at getting a spare bushing. If I do run into problems like this again, I think the idea of having a spacer as you described to just keep the bushing from floating too far out is a good one and something I will look into if needed.

[4mulafastech]

My solution to this exact problem was to change over to Octura lead/teflon 1/4 od bushings. Trimmed the stuffing tube slightly, too some measurements to see how far into the strut the stub shaft goes, drilled the strut out to that depth with a 1/4" bit on a drillpress. Pressed in the bushings and away I went. Took about 15 minutes to do this mod. If you were very careful you could do it with a hand drill more than likely. A small drill press is super handy in this hobby, mine in the basement shop is just a small home depot cheapie.

Thanks for the tip.

[4mulafastech]

You can change the length of your teflon tubing to position the bushing where you what it to sit. I also use a very short section of water line that goes inisde between the collet and teflon tube. It keeps the water out and the tefon in place never any trouble Grim grease every new set of batteries.
I hope this helps you.
Mike

Thanks Mike. You know, you are one of the reasons I ended up deciding on the Revolt! I definitely like your strategy of getting the most out of a stock set-up. When I saw it has the potential for 50+mph with the right tweaks and prop, I was sold. Other than this little mishap I am VERY pleased with the Revolt.

On another subject, I have a couple questions about your Revolt. I was looking through your pictures and like how you made the strut support. What kind of epoxy did you use?

The tie-rod connected from the rudder mount to strut mount, is that a custom piece you made? Did it make a difference in handling?

I don't have a gps to put in my boat, but with the 45x68 S&B and two 4200 mAh 2S, it has to be in the mid 40mph range. I raised the strut .080" from stock which was straight with the bottom. I estimate this angled the prop shaft up 1.7°. It really loosened her up (sometimes too loose, but I kinda like that...) and picked up significant speed. Still playing with CG. By the way, I have an Octura x642 on the way!

[4mulafastech]

Definitely post some pictures of your time trials. It sounds like a lot of fun. Good luck!

I like the thru-transom water outlet fitting you have. Is it the aero-2011 sold here on OSE?

[properchopper]

My solution to this exact problem was to change over to Octura lead/teflon 1/4 od bushings. Trimmed the stuffing tube slightly, too some measurements to see how far into the strut the stub shaft goes, drilled the strut out to that depth with a 1/4" bit on a drillpress. Pressed in the bushings and away I went. Took about 15 minutes to do this mod. If you were very careful you could do it with a hand drill more than likely. A small drill press is super handy in this hobby, mine in the basement shop is just a small home depot cheapie.

I agree 100%. I do this and never had problems.

http://www.offshoreelectrics.com/pro...od=oct-oc6ltsb

[AustinWolv]

On a related note:

Ran my Revolt for the first time this morning. Completely stock on 4S. Motor was around 100-105, and ESC was very cool, batteries were in the upper 120s as I recall it.

Regardless, the bushing on mine comes out of the strut a little bit also. Not all the way out.
It and the flex were greased well before the run. I kept 4.5-5mm between the dog drive and the strut.

As others have mentioned in another thread, I proactively ordered the OSE upgrade assembly to have it in hand if the stock one breaks.