Advancements in drive hardware?

Lonnie Hyde · May 16, 2022

Hello. My name is Lonnie Hyde. I am getting back into the hobby after a very long absence. Before I left the hobby over 20 years ago, some of the boaters were starting to experiment with solid drive shafts and small "U" joints instead of the flex shafts. Did anything develope with this, or did it just go away. Have there been improvements to the flex shaft systems? These are some of the things that I need to catch up on, as not to make serious mistakes as I start over in the hobby. All suggestions with this topic will be greatly appreciated as with all the new kinds of hardware in use today. Please advise when you can. Best regards, Lonnie Hyde.

Daniel's Racing · May 17, 2022

The solid shaft with joints came/left just before the flex shaft. Hardened shafts in needle bearing log with pin and socket joints at engine end or at both ends. The advent of the flex shaft is what made the solid drivelines obsolete to this day. The solid drives almost certainly required solid engine mounting too. Today many of the engines are supported with rubber isolators since the flex will allow for some movement along with the slightly oversize tubing we run them in gives some play at the end too.

That transition to flex cables started just over 40 years ago.

Depends on the power but anything less than a inline twin gas engine a welded stub cable is fine with proper maintenance and a close eye on fatigue at the joint each time you pull it and clean it up for fresh grease. For the inline gas engines we run hollow stub shafts that the cable goes up in so the transition is many times stronger than a butt welded stub type cable.

There are square drives where one or both ends of cable are crushed with hydraulic force to turn the ends square and then they drive in square collets on engine or on the driveline with square drive ferrules. Lots of ways to configure them.

There are also wire drives as they call them where a solid rod is flexed to get out the bottom to the stub shaft.

Lonnie Hyde · May 17, 2022

Thank you for your reply Daniel. I only got into boats in 1975 and the flex shaft was the predominant drive at that time ,although some of the boaters perhaps, were going back to the older way. I was not aware that they had been used before. Thank you for the information. I was recalled back to active military duty at that time, so I never knew anything more after that. The wire drive you mentioned sounds very interesting. I know that a lot of the boaters then ,were concerned about the flex cable chatter causing vibration in their boats, which in time caused damage to the boats. Just getting back into the hobby, I was hoping that this problem might have been eliminated by now. Does the wire drive reduce or eliminate this condition? I am very interested in reducing or eliminating as much as possible, any or all of the vibration in the boat. I have seen the long term vibration results and it is very bad for the boats. Back then we all had wood built kit boats, I do not know how it affects the fiberglass boats of today. I am very interested in stopping or reducing the vibration as much as possible. If you could please advise me little more on how to do this it would be greatly appreciated. Thank you again Daniel. Please advise when you can. Best regards, Lonnie Hyde.

Grimracer · May 17, 2022

Lonnie,

Cables have been the standard' for some time now.. yes.. they can "buzz" when not supported correctly and YEP.. thats bad.

Vibration isolated motor mounts ARE the best option for eliminating vibration to the boat.

Now days.. we use more epoxy then before and wood boats are still quite the norm..

Also.. our radios have "surface mount" components.. so they do a MUCH better job of handing vibration.

and as you know.. a well balanced prop is going to be your BEST prop..

I have developed wire drives for the smaller RC boat industry and they can work is even some of the larger boats.. in the end and after all that's involved.. you will find a cable is just hard to beat with a piston engine boat.

Grim

Danny King · May 17, 2022

Yeah until about 5 yrs ago pretty much everyone ran cables. They are easy and Plenty strong and a bit more forgiving.
The 3/16” solid drives have been a rare sighting mostly the last 20 yrs.
In the last 5ish yrs wire or smaller solid shafts that can sustain some bow in them have become more popular. But flex shaft are still most common. And work fine.
Since your just getting back into the hobby I’d suggest flex shafts as you will have plenty of learning curve in general. You can always later on switch to wire. 21 and 45 Boats use 3/16 flex cables and 67 up to gas use 1/4” cables.
Brent makes great set ups for wire drives from 21 up to gas engines. If you choose that route. He offers .098” and .125” wire/solid shafts.
Brent Byers
[email protected]
That’s his contact.
But flex is a easier way for someone just coming back to the hobby. In my opinion. And I run Brent’s stuff on 10 of 12 of my boats.

SayMikey · May 17, 2022

Danny King said:
Yeah until about 5 yrs ago pretty much everyone ran cables. They are easy and Plenty strong and a bit more forgiving.
The 3/16” solid drives have been a rare sighting mostly the last 20 yrs.
In the last 5ish yrs wire or smaller solid shafts that can sustain some bow in them have become more popular. But flex shaft are still most common. And work fine.
Since your just getting back into the hobby I’d suggest flex shafts as you will have plenty of learning curve in general. You can always later on switch to wire. 21 and 45 Boats use 3/16 flex cables and 67 up to gas use 1/4” cables.
Brent makes great set ups for wire drives from 21 up to gas engines. If you choose that route. He offers .098” and .125” wire/solid shafts.
Brent Byers
[email protected]
That’s his contact.
But flex is a easier way for someone just coming back to the hobby. In my opinion. And I run Brent’s stuff on 10 of 12 of my boats.

10 of 12 you are a STUD Sir

Lonnie Hyde · May 17, 2022

Thank you Grim, for you kind reply. Yes, I pretty much expected that the cables were still in use as the main drive today. I was just trying to find out what is being done differently today. The new motor mounting system is a large difference then what we had back then, and yes a well balanced prop is always needed. You mentioned a well, correctly, supported cable system. Is it done differently today then it used to be? We used to support the shaft tube completely form the hole in the bottom of the boat to just before the coupler, with just enough room to tighten or loosed the engine coupler to the cable and alligned the engine and shaft tube as closely as we could possibly get it. This was done prior to glueing the cable shaft into place. I realize there much better materials today then we had then, especially the new epoxies and other adhesives. Some of the hardware has vastly improved, but still doe the same job, only better. Most of the experience I have is old school, but it still seems the the basics remain pretty much the same, but just a little different. You know,"the old dog new trick" thing will most likely will still apply. I really enjoyed boating a lot back then and am looking forward to doing it again. Thanks for your advice and best regards, Lonnie.

Lonnie Hyde · May 17, 2022

Thank you Danny and SayMikey, for you reply. I just saw it after after I replied to Grimm. I appreciate any and all replies. It all helps me to get started again. Thanks to all for your advise. Best regards, Lonnie Hyde.