motor shaft couplers

[pjdog]

There's got to be a better way to couple the motors to the shafts on these subs. Dumas dog bones leave allot to be desired. They are noisy, a pain in the butt to line up when connecting to the S/D and they break. Some one must make a good rubber connection with brass fittings on the end. I've seen them but I'm unable to locate them now. I find lots of possibilities but they are always over seas some where. Does anybody on the forum have any info they can share.

Jack

[He Who Shall Not Be Named]

There's got to be a better way to couple the motors to the shafts on these subs. Dumas dog bones leave allot to be desired. They are noisy, a pain in the butt to line up when connecting to the S/D and they break. Some one must make a good rubber connection with brass fittings on the end. I've seen them but I'm unable to locate them now. I find lots of possibilities but they are always over seas some where. Does anybody on the forum have any info they can share.

Jack

Not that I know of. You can simply put a rubber tube between the motor and propeller/rotor shaft as illustrated below.

To make installation easier I've put a 'telescoping' section between two dog-bone halves that permits me to insert the intermediate drive shaft between the SD and the propeller/rotor shaft with the SD mounted. Use square section brass tube here so that the unit can expand contract but not spin upon itself when presented with torque. A spring between the two sleeved sections of square tube pushes the unit apart so the dog-bones fit tightly into their respective couplers.

David,

[pjdog]

I did what you've shown on the type VII/C but had the rubber hose on the motor end rather than the shaft end. It works but doesn't look very nice. At high motor speed I do get some vibration. By filling the hose with aluminum it did reduce some of the vibration.

I found on ebay a 'SAB 2004' that is a brass fitting with an 1/8 shaft hole and a grub (set screw). The fitting had lots of grooves in it. That would be perfect to fit hose on sense the grooves would hole on to the hose. But it's in Australia. I can't find any in the good ol' USA. I tried a internet search and could not find any. The fitting is for a u-joint. The fitting goes in each of the u-joint. Nuts. I also found a web site that shows how to make a flex shaft out of a spring.

http://www.fastelectricrc.com/assembling-radio-control-boat-flex-shafts/

This might be an answer to my dilemma.

I'm still looking for a good solution.

Jack

[Rick Teskey]

Can you not use a standard u joint?
loloyal hanna carries a nice splined u joint
Rick

[Kazzer]

Here is one from Raboesch. I think I have a few around. The brass insert can change from 1/8" - 3/16"

[Rick Teskey]

Thats the kind I was thinking of , did not know you carried them.
Another soluition would be use some wheel collars of the shaft size needed slip a piece of tubing over them and drill a hole in the set screw location and use longer set screws that will be flush with or protrude past the o.d of the tubing , this will give a positive "drive dog" effect and prevent slippage
Rick

[He Who Shall Not Be Named]

Thats the kind I was thinking of , did not know you carried them.
Another soluition would be use some wheel collars of the shaft size needed slip a piece of tubing over them and drill a hole in the set screw location and use longer set screws that will be flush with or protrude past the o.d of the tubing , this will give a positive "drive dog" effect and prevent slippage
Rick

Hey! ... I like that.

David,

[Rick Teskey]

Bon Jour Grand Formage!
Standard fuel line for autos could be used altho a bit stiff or clear poly tubing .
How about some cast up collars with nipples/ studs and a length of tubing maybe slide some ferrals on , a new D&E / Caswell product line ( at this rate you will never see the light of day , you will be locked away forever if Mike see's this as yet another viable product line too force you too make )
Tor
P.S. the wife thinks I look more like Jackie Coogan ( uncle Fester)

[He Who Shall Not Be Named]

Bon Jour Grand Formage!
Standard fuel line for autos could be used altho a bit stiff or clear poly tubing .
How about some cast up collars with nipples/ studs and a length of tubing maybe slide some ferrals on , a new D&E / Caswell product line ( at this rate you will never see the light of day , you will be locked away forever if Mike see's this as yet another viable product line too force you too make )
Tor
P.S. the wife thinks I look more like Jackie Coogan ( uncle Fester)

Rick,

Honestly, that's a very good idea you have there -- with your permission I'll pursue refinement of the design and put it into production. Does this mean I have to be nice to you?

(for those looking over our shoulder: I joked once that Rick looks a lot like Swedish professional wrestler and grade-D movie star, Tor Johnson. Here's a shot of Tor in his prime: http://us.imdb.com/name/nm0426363/ ).

David,

[redboat219]

What about rare earth magnets like you got in the Kli-cons?

[pjdog]

I'm going to try these on my Revell type VII.

I think they will take any bind off the motors.
They telescope.

jack

[He Who Shall Not Be Named]

I'm going to try these on my Revell type VII.

I think they will take any bind off the motors.
They telescope.

jack

Mike .... I like it. What do you think?

David,

[Rick Teskey]

Dave go right ahead run with it , as far as being nice too me , why start now?
Rick