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Boaterguy
06-20-2011, 10:03 PM
I was wondering what the difference is between the two, wire drives are thinner, does that make them stronger? what application is either better for?

NativePaul
06-21-2011, 03:52 AM
Wires are only suitable for relatively shallow bends whereas a flex can take quite a tight bend as in an outboard, if you have a long driveline a wire is better as you need a stuffing tube the full length of a flex to stop it tying itself in knots but a wire only needs a couple of inches of stuffing tube to get it through the hull. setting them up is different too, I take the thrust at the motor with flex shafts but take the thrust at the strut with wires. Either can be stronger depending on the size, the fatter the stronger for both, I would say 1.6mm wire is an equivalent to .130 flex, 2mm wire half way between .150 and .187 flex, I've never tried 2.5mm but would guess its getting on for as strong as 1/4" flex.

Wires are perfect for stepped monos with the motor placed forward of the step, good for monos, cats and hydros if the motor is placed up front, and bad for any hull with the motor at the back. Flexies are perfect for outboards, any hull with rear or mid mounted motors but inferior for most hulls with front mounted motors.

FighterCat57
06-21-2011, 04:44 AM
I was wondering what the difference is between the two, wire drives are thinner, does that make them stronger? what application is either better for?

Wires are great for high RPM, where less resistance is desired.

I've used the wires in an apparition & genesis, with a decent bend. Had some break, but most last quite a while. Best is for use in a v-hull or twin cat with minimal bend. The cat's are great for wire drives. .078 is good for a 447 prop on 6s...

Also, they don't shrink under load, so no need for thrust bearings.

:cool2:

sailr
06-21-2011, 07:53 AM
My first foray into wire drives was in my 1/10th scale hydros. They have held up exceptionally well. I'm contemplating switching to wire in some of my other boats because I'm sick and tired of twisting off flexshafts!. Just curious about sizes readily available. Biggest I have seen is .072 which is only 1.8mm.

iamandrew
06-21-2011, 08:05 AM
can someone point me to a guide for bending a 3/16th drive setup?
im about to remove mine out of the genesis and change it to the 3.16th size
e.g. do i bend the tube with everything inside it?

FighterCat57
06-21-2011, 08:14 AM
can someone point me to a guide for bending a 3/16th drive setup?
im about to remove mine out of the genesis and change it to the 3.16th size
e.g. do i bend the tube with everything inside it?

I typically lay the brass flat on the bench and gently bend it with my thumbs and fingers twisting my wrists and working my way down the tube with a little bend at a time eventually making the entire bend. If you have a cable to keep inside, it won't hurt, but don't think it will prevent kinking.

The most difficult part is using just enough pressure as not to king the tube and just bend it.

I'm hoping there's a better way that someone can share.

Diegoboy
06-21-2011, 08:19 AM
Here's (http://www.offshoreelectrics.com/info-pages/bend-brass-tubing.php) some info

Boaterguy
06-21-2011, 09:30 AM
that's what I was going to say too, OSE has many good articles.

oscarel
06-21-2011, 10:04 AM
Wires are good for twins also because you don't have to worry about what direction they spin.

iamandrew
06-21-2011, 06:33 PM
ah ok I checked it out, ive got a camping stove which might be allright to bend it, the genesis hull only requires one gentle bend so it shouldnt be too much of a problem.

NativePaul
06-21-2011, 08:36 PM
I think .078 is the standard large wire its just under 2mm but close enough that i can use 2mm wire thats available here in Europe with a quick spin in 1500 grit wet and dry, ETTI make 2.5mm wire shafts for their mono2 not that its needed for the power but its a dead straight run with no stuffing tube as a centre bearing and wires need a little bend they tend to whip if straight. Jeff also makes some bigger wires for SAWs .09something i cant remember.

i bend all my stuffing tubes whether for wire or fles over my thembs without annealing and havent broken one yet, IMO K&S brass is plenty soft enough already.

bbosncali
06-26-2011, 10:48 AM
I use a small pipe bender from homedepot but as I learned from my first 2 tubes bend it with everything in it this will help it from kinking. I had to bend my stuffin tube fr my genesis build and went through 2 stufing tubes before I figured it out but either way use very small bends at a time. P.s. thanks fightercat for having extra stuffing tubes in stock lol

Boaterguy
06-26-2011, 06:26 PM
I will anneal mine, I think I will make a template out of cardboard and make bends based on the template, I may solder on caps and put salt in, although salt + heat = ?

tanasit
06-26-2011, 06:43 PM
With the flex cable left inside, I slip a piece of spring that is just big enough to go over the brass tube and gently bend between 2 thumbs and 2 index fingers.
If you push too hard, it may still kink though.

LarrysDrifter
06-26-2011, 07:19 PM
Anneal the tubing. Let it cool. Cap off one end with a vaccum cap, fill with salt, cap off that end. Bend tube over car tire or other round object. Bend a little at a time and check. Using the salt method does not require annealing. It can be done either way. No need to put the flex in the tube while you bend it. Salt keeps the tube from kinking. Look in the tips and info section for how-to's, they are helpful and really work.

Boaterguy
06-26-2011, 07:39 PM
alright, I just want to make sure I do it right, I'll anneal and put the flex in, and bend it with my hands.