Wire Drive

[dwilfong]

I have bin battling tail weight and over all boat weight. The 3/16 drive seams to be a good place to try and lighten up the boat.

What are the thoughts and experiences with a wire drive in a 21 rigger.

David

 

[Chris Wood]

i know the electric guys use it.. i think glenn quarles has been playing with it.. BUT i don't know if the weight of our nitro motors and boats vs the electric stuff is the reason it is harder to keep the wire drive together... i know the electrics can dia up ALOT more HP than nitro so i know that isn't it.

can you get away with smaller hardware.. smaller strut.. and strut and rudder bracket.

what about the MAIN stuffing tube that is glued into the boat.. what about using alum instead of brass.

how much tail weight are you talking about..

as for over all boat weight.. alum screws, small throttle and needle servo's.. drill out anything you can.. that is what i do.

let me know

chris

 

[dwilfong]

i know the electric guys use it.. i think glenn quarles has been playing with it.. BUT i don't know if the weight of our nitro motors and boats vs the electric stuff is the reason it is harder to keep the wire drive together... i know the electrics can dia up ALOT more HP than nitro so i know that isn't it.

can you get away with smaller hardware.. smaller strut.. and strut and rudder bracket.

what about the MAIN stuffing tube that is glued into the boat.. what about using alum instead of brass.

how much tail weight are you talking about..

as for over all boat weight.. alum screws, small throttle and needle servo's.. drill out anything you can.. that is what i do.

let me know

chris

I started cutting down the ruder bracket and the strut bracket and got the tail down to 374g. Want to try aluminum screws but they are quit pricey

Trying some fiberglass carbon composite boom tubes for kits. This made some stiff tubes.

Have bin whittling away at it for some time but it comes off slow. The drive seams to be where the most head way can be made.

Moved the steering servo forward and have small servos for the throttle and 3rd channel. Went to a 4 cell AAA pack also. Even had to take your dads muffler off and went with a internal stinger.

There is a lot of weight in the drive. Have plans for a liter build but want to try thing on this tub first.

David

 

[TinoAlmanza]

One of the long time FE guys was saying he thinks it's the pulses the combution engines make that seems to disagree with wire drive. No real proof just theories.

 

[Hydro Junkie]

That's my thought as well. The electric drive has an almost constant speed coming out of the motor while the nitro motors rev and slow each time the engine goes around. I know the flywheel is supposed to minimize it, but inertia can only do so much

 

[Glenn Quarles]

David, unless you can get a wire setup much stronger than the ones I make I would discourage trying it. I have been having so-so luck with them in my .12 boat. They run really good and are super easy to take care of, but I have broke them in a bunch of different ways (I keep chasing the failure points and hope to have a dependable one soon). You will have to use wire bigger than the 1/16" I using and if your stuffing box has much bend in it you may have to much drag with a bigger, stiffer wire.

If you need any more detail let me know.

Glenn

 

[dwilfong]

David, unless you can get a wire setup much stronger than the ones I make I would discourage trying it. I have been having so-so luck with them in my .12 boat. They run really good and are super easy to take care of, but I have broke them in a bunch of different ways (I keep chasing the failure points and hope to have a dependable one soon). You will have to use wire bigger than the 1/16" I using and if your stuffing box has much bend in it you may have to much drag with a bigger, stiffer wire.

If you need any more detail let me know.

Glenn

Glenn

There is very little bend in my tube. You said that 1/16 would be too small. What is out there for wire and how much clearance is needed in the tube.

Would a Teflon liner help or would it just melt.

I will give it a try just need some more info. The local hobby shop has all the Ocutra stuff in stock in the way of shafts and couplers.

I am gearing up for a SAW boat and think this would be the way to go. I am planing on a thin balsa tub with a epoxy carbon fiber overlay.

David

 

[TinoAlmanza]

Jeff Wholt online store

Mr. Wholt is a very good wire drive builder. He is a good person to ask anything wire drive.

 

[BB Mods's]

David, get with me next week, I have something you need for this endeavor.

 

[Glenn Quarles]

David, yes get with Jeff Wholt! He knows WAY more about wires than I do. I think the size wire that you will want is .078 (not sure). I'm still not sure it will stand up to a .21 motor, but it will be fun to see! Jeff may use better stuff to build his wires and there may be no trouble at all.

I use the same size stuffing box for the 1/16 wire as I do for the .130 cable (3/16 OD) and I have never seen signs of whipping or anything. You may be able to get by with the same stuffing box you already have. I would try it before you make any changes! No on the teflon liner. Oh yeah...you will be pushing against the strut with the wire (no more cable shrinkage to deal with) so you will need to get some king of good trust washer to put between the drivedog and strut. Does Octura make a wire size coupler for a 1/4 X 28 thread? That would be cool! If not let me know and I can tell you how I use to handle it before they started making these for my .12's.

Glenn

 

[dwilfong]

David, yes get with Jeff Wholt! He knows WAY more about wires than I do. I think the size wire that you will want is .078 (not sure). I'm still not sure it will stand up to a .21 motor, but it will be fun to see! Jeff may use better stuff to build his wires and there may be no trouble at all.

I use the same size stuffing box for the 1/16 wire as I do for the .130 cable (3/16 OD) and I have never seen signs of whipping or anything. You may be able to get by with the same stuffing box you already have. I would try it before you make any changes! No on the teflon liner. Oh yeah...you will be pushing against the strut with the wire (no more cable shrinkage to deal with) so you will need to get some king of good trust washer to put between the drivedog and strut. Does Octura make a wire size coupler for a 1/4 X 28 thread? That would be cool! If not let me know and I can tell you how I use to handle it before they started making these for my .12's.

Glenn

Glenn

I run a square drive now with a Teflon thrust washer with good results, have never had to change the washer yet.

I had a 62 tempest with a solid drive shaft that ran in a arc under the car. I think the trick is to bend the tube in a constant arc and not touch the tube.also I think bearings in the strut would help with the side load at the strut. Using a small tube I am thinking would cut down on drag in the water.

Octura makes some very small strut setups may try one and see what happens. Will keep you posted on the results.

David

 

[dwilfong]

David, get with me next week, I have something you need for this endeavor.

Tommy

Let me know what time is good.

David

 

[Glenn Quarles]

David, yes get with Jeff Wholt! He knows WAY more about wires than I do. I think the size wire that you will want is .078 (not sure). I'm still not sure it will stand up to a .21 motor, but it will be fun to see! Jeff may use better stuff to build his wires and there may be no trouble at all.

I use the same size stuffing box for the 1/16 wire as I do for the .130 cable (3/16 OD) and I have never seen signs of whipping or anything. You may be able to get by with the same stuffing box you already have. I would try it before you make any changes! No on the teflon liner. Oh yeah...you will be pushing against the strut with the wire (no more cable shrinkage to deal with) so you will need to get some king of good trust washer to put between the drivedog and strut. Does Octura make a wire size coupler for a 1/4 X 28 thread? That would be cool! If not let me know and I can tell you how I use to handle it before they started making these for my .12's.

Glenn

Glenn

I run a square drive now with a Teflon thrust washer with good results, have never had to change the washer yet.

I had a 62 tempest with a solid drive shaft that ran in a arc under the car. I think the trick is to bend the tube in a constant arc and not touch the tube.also I think bearings in the strut would help with the side load at the strut. Using a small tube I am thinking would cut down on drag in the water.

Octura makes some very small strut setups may try one and see what happens. Will keep you posted on the results.

David

Yeah the ball bearings in the strut are the only way to go!

Glenn

 

[TinoAlmanza]

Mr. Wholt sells those too.

I think I should ask for an advertising fee lol.

Liners are fine. As for stuffing tubes I don't even run one. I have about a 2" piece that exists the hull. I run a teflon liner to the strut just because it's easier to make the hull water tight.