Whos making these wire drive coupling systems?

[eXoNerated]

2a09d0ef-a433-4e13-bbd9-2b38151882d4.jpg

Can you help me? I'd like to make a few or buy a few whichever comes first. Is there a link to the original thread from which this came?

Thanks
Hubert

[Dr. Jet]

Not exactly the same, but similar: http://www.rcraceboat.com/StoreCoupler.html

[eXoNerated]

Hi Dr. Jet,
I have all those and they work well but this style is to said to have a TIR of .0001 That would be better than anything seen and as long as there is a slight interference fit the grub screws wont match its gripping power. It also wont mar or dimple the drive line. The modified mill collets carry more weight than I want to on the rotating assembly . I want something light and with a powerful grip and as true as possible. To ensure concentric all from the same end with out removing the workpiece you do the large bore first and the smaller 2nd. The bores are all done from one end and as u can see it is simply one piece with the splits and the counter bored cap heads to clamp the motor shaft and wire. Obviously if you are building it then u can make it for any size wire. I even wounder could a wire ferrule be made this way then props can be saved in the event of a snap. The standard wire bores available wont cut it I'm afraid.

Regards,
Hubert

[Dr. Jet]

The GP-1 connectors I used in the 1/20 scale hydros were of the same design concept and you are 100% correct about grip strength and non-marring. It's a simple enough machining project, but there would be a lot of time invested to make a small quantity. I will follow this thread to see if you find such a creature.

I like the idea of a prop ferrule, but it's probably only plausible for applications larger than I generally tend to use.

[bhorowitz]

Ask Tyler Garrard. I believe he is the one who posted that picture. He is on here a lot.

[bhorowitz]

He goes by RacemechaniX

[RaceMechaniX]

Hello Hubert,
Those are special SAW couplers we made in a small batch for several of us. I am not sure who made the original design, but Jochen at MBP was producing something similar for a while, but not in the size we needed so I designed the one in the pic and they were machined in Germany. They are intended for 8mm LMT motors and a specific 2.5mm wire.

-Tyler

[eXoNerated]

Hi Tyler,

For my next scale I want to move away from bent flextshaft or wire to a long straight one pushing the motor into the canopy. Do you know of any source of rod tru and strong enough to do the job with big motor torque? 4mm ASTM A228 spring steel?
Thanks for your time and patience.
Hubert

[Dr. Jet]

Do you know of any source of rod tru and strong enough to do the job with big motor torque? 4mm ASTM A228 spring steel?

https://shop.sdp-si.com/catalog/?cid=p466&filter=a93%3A2%3A4%20(-.004%2F-.012)&sort=undefined&view=table

[eXoNerated]

Hi Dr Jet,
No luck as they are all too short for a 1200mm scale hydroplane to mount the motor beneath the canopy. I think the carbon spring steel will work. Just wondering is there a more consistent rod than what K&S offers.

ASTM A228
1590 - 1760 MPa
@Diameter 6.35 mm 231000 - 255000 psi
@Diameter 0.250 in
1640 - 1820 MPa
@Diameter 5.26 mm 238000 - 264000 psi
@Diameter 0.207 in
1690 - 1860 MPa
@Diameter 4.50 mm 245000 - 270000 psi
@Diameter 0.177 in
1740 - 1920 MPa
@Diameter 3.81 mm 252000 - 278000 psi
@Diameter 0.150 in
1770 - 1950 MPa
@Diameter 3.56 mm 257000 - 283000 psi
@Diameter 0.140 in
1800 - 1990 MPa
@Diameter 3.18 mm 261000 - 289000 psi
@Diameter 0.125 in
1870 - 2070 MPa
@Diameter 2.54 mm 271000 - 300000 psi
@Diameter 0.100 in
1940 - 2150 MPa
@Diameter 2.00 mm 281000 - 312000 psi
@Diameter 0.0787 in
2020 - 2230 MPa
@Diameter 1.60 mm 293000 - 323000 psi
@Diameter 0.0630 in
2090 - 2310 MPa
@Diameter 1.30 mm 303000 - 335000 psi
@Diameter 0.0512 in
2170 - 2410 MPa
@Diameter 1.00 mm 315000 - 350000 psi
@Diameter 0.0394 in
2250 - 2490 MPa
@Diameter 0.810 mm 326000 - 361000 psi
@Diameter 0.0319 in
2350 - 2600 MPa
@Diameter 0.610 mm 341000 - 377000 psi
@Diameter 0.0240 in
2500 - 2760 MPa
@Diameter 0.400 mm 363000 - 400000 psi
@Diameter 0.0157 in
2600 - 2880 MPa
@Diameter 0.300 mm 377000 - 418000 psi
@Diameter 0.0118 in
2750 - 3040 MPa
@Diameter 0.200 mm 399000 - 441000 psi
@Diameter 0.00787 in
3030 - 3340 MPa
@Diameter 0.100 mm 439000 - 484000 psi
@Diameter 0.00394 in

Modulus of Elasticity 210 GPa 30500 ksi
Poissons Ratio 0.313 0.313 Calculated
Shear Modulus 80.0 GPa 11600 ksi

Thanks,
Hubert

[RaceMechaniX]

Hubert,

You need to tell us more about your boat and power system so we can recommend a driveline.
Generally I do not recommend wire drives over flex cables unless you are running SAW or have an application like a mono with front mounted motor and barely any bend in the shaft.
Brent Byers on Jim's RC Boat Dock does build 3mm wire drives for gas motors which are very durable, but you will need a special collet to couple it.

If you are running a truly high torque/high pole count motor a 1/4" flex cable is hard to beat. If 1/4" is not enough I believe some gas model boat supply shops are building 5/16" flex cables.

so first let's hear about your power system.

[Dr. Jet]

Yeah, the longest shaft I saw there was 350mm. They do have longer lengths in larger diameters (I just gave a link for 4mm shafts). Maybe two 350mm shafts with a pillow block bearing and a flex coupling in the middle? I have another thought: The driveshafts on our (RWD) vehicles is a hollow tube with a U-joint at either end. Maybe an appropriate length 4130 aircraft tubing would make a decent shaft, then you could get somebody with a lathe to make appropriate ends for it, braze (or TIG weld) it all together and chrome plate it. Don't know if it would be true enough for the kind of RPMs needed.... Maybe intermediate bearings?

See: https://www.aircraftspruce.com/catal...clickkey=39109

Here is an 8mm precision ground 420 stainless steel shaft that is 1 meter long: http://shop.sdp-si.com/catalog/produ...0PX0MCHS08-A00

[eXoNerated]

4 wing bud2.jpg
strut from the bottom.jpg

I want to run a straight shaft with a low angle of attack between 3 and 4 mm with the motor all the way up in the canopy of the boat. I found some precision shafts in Germany up to 2 meters in bearing grade stainless. A 8 mm one meter shaft would be a great alignment tool, but its larger than I would need. Surge Power is in the 10-20kW range. 4mm should be enuf 3 would probably work. Here's my friend from Germany's <1000mm T4 boat as an example. Here can see the 4mm shaft of carbon spring steel coupled to a 2215 Neumotor.


Regards.
Hubert

[RaceMechaniX]

Hubert do you have a motor selected yet?
I would opt for 5mm straight shaft if you really want to run one. This would allow you to pass the shaft through a ball bearing supported strut and mount the prop directly on the shaft assuming you are running a 3/16" or 5mm prop. If you run 1/4" bore props you will need a precision stub shaft. Perhaps you can use a stub shaft from the large cats.

[eXoNerated]

Hi Tyler.
About the OEM motors. It seems our bodies put the 15XX Neu at a disadvantage slating it against any 22xx s lehner or 370 in scale FE unlimited hydro.

Section J Fast Electric Rev. 2019

e. Only one brushed motor of any type or one brushless motor from the following types, Lehner22xx series, Neu 15xx series and Plett 370. Any other brushless motor is subject to technical approval.

Is this also the case for S&T sport hydro?

Those last two motors are larger than even the 1530. The new FE scale powerplant rules confuses me even more. It says the added motors cannot be used for speed trails? Not that id want to run one of those added but why? Wat determines if a motor would be approved or not. The idea of "excessive hardware" is worded in there somewhere.

Is there a reason brass sleeves equally spaced wont work with the 3/16 wire? The other issue is how to fasten all this on the prop end. Any ideas?

Thanks,
Hubert.