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[Ghost14]

Hey guys,

In the past, I have used solid, non flexible, prop shafts for my models.  I am thinking about using a flex cable for my drive train for my new model but I don't know much about them.   Am I able to shorten these cables if the ones I'm looking at are to long??  I've never held one or worked with one so I'm not sure if it something that can be altered.  The one I'm looking at can be found in the link below.  It says its 13.75" (~305mm) long but I'd like to cut it down to to roughly 200mm.  Thanks for the help!

-Ghost-

http://www3.towerhobbies.com/cgi-bin/wti0001p?&W=000355169&I=LXVXS5&P=K

[andyn]

Put in in a vise, tighten it so the grips just touch it, then saw it to size with a fine toothed saw blade, you'll need to hold it. Go very slowly, and make sure the metal doesn't 'blue'. When I cut one up yesterday, I stopped when it got warm and ran it under cold water.

[Ghost14]

So cutting the flexible part of the drive cable has no impact on its physical properties in terms of function.  In other words, the cut end won't deteriorate if I clamp it to the drive shaft?  Thanks for the assist.

-Ghost-

[Martin (Admin)]

I don't know if it's the best way buy I cut my flex cable by I filling the cutting area with soft solder and used an abrasive disk type cutter in a Dremell type drill.

[Rex Hunt]

I don't know if it's the best way buy I cut my flex cable by I filling the cutting area with soft solder and used an abrasive disk type cutter in a Dremell type drill.

Beat me to it by about 8 minutes!

It is exactly what I did with my Bowden cables.


Rex

[poll]

Hi Ghost14.     I do believe the flex drive is designed to run one way. Just a thought if it was for a tug.

John

[andyn]

So cutting the flexible part of the drive cable has no impact on its physical properties in terms of function.  In other words, the cut end won't deteriorate if I clamp it to the drive shaft?  Thanks for the assist.

-Ghost-

Not at all, though if you are using a grub screw type coupling, I like to have a brass collar on the end, that is soft soldered on.

Flexishafts are for one way use only, they unwind if you run them too fast in the opposite direction.

[Ghost14]

Thanks for all of the info guys.  Just for your reference, this was the coupling I was planning to use.  If you see any issue with that, please let me know.  My shipment of balsa came in yesterday so I'm excited to start building.  

http://www3.towerhobbies.com/cgi-bin/wti0001p?&W=000355169&I=LXMWA8&P=K

[andyn]

Coupling should be ok, we've found that you really do need to do those up tight otherwise they undo themselves. You won't need a collar on the shaft with that coupling.

What you will need, however, is to get a length of plastic pipe a couple of inches shorter than the shaft, with the end blocked off. This needs to be filled with oil. Hang it in a corner of the shed and keep the shafts in it after each run. You want to then before each run coat the shaft with this stuff:

http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_246319_langId_-1_categoryId_165705

If you don't keep a flexishaft well lubricated, they make a horrendous scratchy-screechy noise when you run them in the boat, which will inevitably lead to them snapping.