Help me out a little...making my own flex shafts

[kfxguy]

You must use hardened steel shafts for needle bearings. Why use those when a caged bearing is better abec 5 and 7 bearings can withstand 60,000+ rpms? I have sold many. You want to lube them?....just remove both inner shields of each bearing and drill a small hole in the strut to use a needle oiler to fill it up. Octura never designed anything to withstand high rpms. Many will disagree that a bearing strut does not help...but eventually with torque on the brass sleeve of these struts it will go and get sloppy. I still do not like a brass sleeve bearing spinning in the stuffing tube...just me. Anything will last a while with enough grease on it. The inner spinning sleeve was designed for nitro guys years ago....most of their boats was a motor and a mess from grease everywhere...they generally never ran teflon either. I had my share of nitro messes. Then I found plettenberg...still have 5-6 of them...man they could suck the amps out of round cells...burned many and then came Aveox brushless!!

Agree 100%.

[Jeff Wohlt]

You must use hardened steel shafts for needle bearings. Why use those when a caged bearing is better abec 5 and 7 bearings can withstand 60,000+ rpms? I have sold many. You want to lube them?....just remove both inner shields of each bearing and drill a small hole in the strut to use a needle oiler to fill it up. Octura never designed anything to withstand high rpms. Many will disagree that a bearing strut does not help...but eventually with torque on the brass sleeve of these struts it will go and get sloppy. I still do not like a brass sleeve bearing spinning in the stuffing tube...just me. Anything will last a while with enough grease on it. The inner spinning sleeve was designed for nitro guys years ago....most of their boats was a motor and a mess from grease everywhere...they generally never ran teflon either. I had my share of nitro messes. Then I found plettenberg...still have 5-6 of them...man they could suck the amps out of round cells...burned many and then came Aveox brushless!!

[78MaicoRider]

Ok so can stainless be hardened to work with needles.

There are many different types of steel and stainless steel. 300 series stainless cannot. 400 series can be hardened. The material used for stainless steel bearings is what you would want to use.

[ray schrauwen]

Good info Martin, thx!

[martin]

Aeromarine stub shafts are hardened & ground to .0001" tolerance that can be used in needles, they sell just the stubs or complete welded flex assemblies.

[ray schrauwen]

In the needle bearing setups, Is the stub shaft the inner race? If so are you using hardened (Rc60 min) stub shafts? The needles will eat up steel that is not hardened. If the stub is stainless, it is difficult to get stainless hard enough to run needles directly on and last.

I'm guessing that some stubs are stainless and some are not. The less you pay,....?

Hughey stubs were hardened steel I think?????

[srislash]

Ok so can stainless be hardened to work with needles.

[kfxguy]

In the needle bearing setups, Is the stub shaft the inner race? If so are you using hardened (Rc60 min) stub shafts? The needles will eat up steel that is not hardened. If the stub is stainless, it is difficult to get stainless hard enough to run needles directly on and last.

I didn't want to say anything about that and it was on my mind the whole time when needle bearings were brought up.....glad someone else did :) but I agree.

[78MaicoRider]

In the needle bearing setups, Is the stub shaft the inner race? If so are you using hardened (Rc60 min) stub shafts? The needles will eat up steel that is not hardened. If the stub is stainless, it is difficult to get stainless hard enough to run needles directly on and last.

[kfxguy]

Speaking of shafts... Any of you guys know where I might be able to find 6mm shafts drilled for spring steel wire (2mm or 2.5mm) ?

Also, do any of you guys use Speedmaster or MTC struts for Twin Cats? I was thinking to use the flat bottom ones one of my cats... but it seems like they can prove to be a bit annoying to adjust and to keep water out (was thinking to maybe use a rubber hose of some sort between the strut tube and the transom stuffing tube and do the same in the area between the flex cable, collet stuffing tube to keep the water out...)

I've been hunting for some good quality flex cable lately-- came across 5mm Gundert (is this 4.75mm?), 4.75mm MTC (Model Center Lorenz), and the hydromarine.de 4.75mm cable.
Which ones do you guys think is best and strongest cable out of all those?

I would create your own thread for some of those questions. We are kinda getting off topic lol

[dmitry100]

Speaking of shafts... Any of you guys know where I might be able to find 6mm shafts drilled for spring steel wire (2mm or 2.5mm) ?

Also, do any of you guys use Speedmaster or MTC struts for Twin Cats? I was thinking to use the flat bottom ones one of my cats... but it seems like they can prove to be a bit annoying to adjust and to keep water out (was thinking to maybe use a rubber hose of some sort between the strut tube and the transom stuffing tube and do the same in the area between the flex cable, collet stuffing tube to keep the water out...)

I've been hunting for some good quality flex cable lately-- came across 5mm Gundert (is this 4.75mm?), 4.75mm MTC (Model Center Lorenz), and the hydromarine.de 4.75mm cable.
Which ones do you guys think is best and strongest cable out of all those?

[ray schrauwen]

I used needle bearings in my Cheetah on 4s and so far I like them. Again, like Terry, not high rpm. 1900kv on 4s.

The reason I used them was because the large Octura strut had the perfect ID for them and the bearing ID was 3/16", perfect for my driveline. It was convenient.

[T.S.Davis]

Using the needle bearings in a big strut with a 1/4" drive. So RPM are lower than you guys run. I've been up to a 462 on that setup. Never thought about a high RPM setup on those. Hmmmmm Have to think on that some.

Edit.......I don't have a lot of laps on that setup now that I think about it. It might be premature for me to say it's stellar.

[srislash]

I've done it a multitude of ways. From .032 wire to .098 on a gear drive. Ball bearings. Sleeve bearings. Over sized struts for bigger bearings. All kinds of stuff. I even have a strut with needle bearings. That one is really cool. Tuff as nails that one.

Alright we(Chris, Travis? and myself) were discussing needle bearings as I would think they would be tuffer than rollers provided a dead straight prop shaft is used. And here you are with proof? Excellent! So oversize strut? Limited RPM.?

[kfxguy]

You're too sensitive on this Travis. You asked about my bearings. I shared how I do mine. I don't have 20 years of boating experience either but I do have thousands of laps and a hand full of SAW passes under my belt. Doesn't mean a thing I know but don't assume I haven't tried umpteen different shaft setups.

I've done it a multitude of ways. From .032 wire to .098 on a gear drive. Ball bearings. Sleeve bearings. Over sized struts for bigger bearings. All kinds of stuff. I even have a strut with needle bearings. That one is really cool. Tuff as nails that one.

Don't mean to come off as being sensitive. Just had good intentions with my post and it sounded a little like your were getting sensitive with the "what you do vs what I do" comment. I just wanted to stop any argument or ill feelings before they started. We just became "cool" with each other instead of always bumping heads. I think we have more to offer each other not being at each other's throat all the time. That being said, I've learned a lot from you guys, and I try to give it back any time I can. Maybe I shouldn't because some people get offended when some "new" guy or "outsider" comes on their forum and tries to lend advice. (Who the heck am I to do that anyway?! Lol)