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        Discussion Newbie help to attach propeller

#1 rightnow Nov 18, 2012 06:59 AM

Newbie help to attach propeller
 
Hello guys and girls,

I got an RC airplane when i was a kid, that crashed on the first flight. Now 15 years later i have started to repair it. Im almost finished but cant attach the new propeller.

I'm sorry, but im a newbie.

The engine has an axle, on to that im supposed to put a adapter of some sort (see my pictures). This one should be squeezed tight using a cone shaped (inside) nut.

Problem is, i cant get the nut onto the cone shaped adapter. I dont know how to push it on. It needs a big amount of force it seems? Please help

http://i47.tinypic.com/oa205y.jpg

http://i48.tinypic.com/288m7f6.jpg

http://i50.tinypic.com/vdmfmg.jpg

#2 jackerbes Nov 18, 2012 07:17 AM

It looks like what you need is a "collet style" prop adapter or a "grub screw" type prop adapter. Those have to be sized to the shaft so you need to measure the size of your shaft. Here is a page full of prop adapters:

http://www.headsuprc.com/servlet/the...ers/Categories

and here is one of each type:

"collet style" prop adapter - http://www.headsuprc.com/servlet/the...r-3.0mm/Detail

"grub screw" prop adapter - http://www.headsuprc.com/servlet/the...for-4mm/Detail

If they do not have the size you need there, there are probably other dealers that will have one that will work. Post the size here and we will tell you where you can get it...

Jack

#3 RedLine19k Nov 18, 2012 07:18 AM

http://thumbs1.ebaystatic.com/d/l225...ncpZ5pMwpw.jpg

the nut and washer hold the prop, which pushes the backing plate/cone and compresses the collet onto the shaft. it will never be tight until the prop/spinner/nut is added. The back "nut" with the cone inside is just so you can keep it from spinning when the prop nut is tightened. Most of the cone parts are round.

more google images

#4 rightnow Nov 18, 2012 07:38 AM

Quote:

Originally Posted by RedLine19k (Post 23298301)
http://thumbs1.ebaystatic.com/d/l225...ncpZ5pMwpw.jpg

the nut and washer hold the prop, which pushes the backing plate/cone and compresses the collet onto the shaft. it will never be tight until the prop/spinner/nut is added. The back "nut" with the cone inside is just so you can keep it from spinning when the prop nut is tightened. Most of the cone parts are round.

more google images

Yeah i have all the stuff like that! I have the washer and nut. Problem is when i try to tighten the nut and washer, everything spins with the engine. Also the "nut with cone inside".

#5 jackerbes Nov 18, 2012 07:41 AM

Quote:

Originally Posted by rightnow (Post 23298390)
Yeah i have all the stuff like that! I have the washer and nut. Problem is when i try to tighten the nut and washer, everything spins with the engine. Also the "nut with cone inside".

Does the collet (the tapered part that slides over the shaft) fit the shaft closely? And does it clamp down on the shaft when the nut on the front of the prop is tightened?

Jack

#6 rightnow Nov 18, 2012 07:49 AM

Quote:

Originally Posted by jackerbes (Post 23298404)
Does the collet (the tapered part that slides over the shaft) fit the shaft closely? And does it clamp down on the shaft when the nut on the front of the prop is tightened?

Jack

Yes it fits very closely. If i put that cone-nut over it before i put it on the axle, i would never be able to get it on. But when i try to tighten the nut, the cone-nut slides over it.

Maybe if i can do something with that screw that it screwed in at the end?

#7 jackerbes Nov 18, 2012 09:51 AM

The screw at the end is to hold a spinner on.

Imagine the collet and inside of the nut as having matching tapers. When the "nut" (the proper name for the nut would "collet closer") is forced back towards the motor and larger end of the taper, it causes the fingers of the collet to clamp down on the shaft.

If the nut is not going back far enough to close the fingers, it is probably because you also need to have a washer-like piece (called the prop hub/collet closer in most cases) between the back of the prop and the nut or closer.

Then, there would be another washer on the front of the prop, then the nut goes on the exposed thread on the end of the prop adapter. You can see all the parts on the adapter's shaft/collet here.

http://aircraft-world.com/shopexd.asp?id=5120

The parts are, from left to right, prop nut > prop washer > prop hub/collet closer > collet gripping fingers

When the nut on the front of the adapter is tightened it forces the washer, prop hub, and prop hub/collet closer back twoards the motor and the tapers cause the fingers to grip the shaft.

You want to take all the slack out with you fingers, hold the prop blades and prop hub/closer against turning, and then tighten the nut to take all the play out. When you use a wrench, you only want to apply a light clamping force or it will stretch the aluminum where the threads are and break the shaft.

So tighten it lik 1/8th of a turn and see if the collet slips on the shaft. it if does, only tighten 1/8th turn more and test again. When it will not slip you are done.

If the shaft is highly polished you can take 300-400 grit emery cloth and slide it lengthwise down the shaft to create some small striations on the shaft. That will improve the collets grip on the shaft.

Also, degrease the shaft and inside of the collet with alcohol or acetone or a good degreaser.

Jack

#8 rightnow Nov 18, 2012 11:21 AM

Quote:

Originally Posted by jackerbes (Post 23299123)
The screw at the end is to hold a spinner on.

Imagine the collet and inside of the nut as having matching tapers. When the "nut" (the proper name for the nut would "collet closer") is forced back towards the motor and larger end of the taper, it causes the fingers of the collet to clamp down on the shaft.

If the nut is not going back far enough to close the fingers, it is probably because you also need to have a washer-like piece (called the prop hub/collet closer in most cases) between the back of the prop and the nut or closer.

Then, there would be another washer on the front of the prop, then the nut goes on the exposed thread on the end of the prop adapter. You can see all the parts on the adapter's shaft/collet here.

http://aircraft-world.com/shopexd.asp?id=5120

The parts are, from left to right, prop nut > prop washer > prop hub/collet closer > collet gripping fingers

When the nut on the front of the adapter is tightened it forces the washer, prop hub, and prop hub/collet closer back twoards the motor and the tapers cause the fingers to grip the shaft.

You want to take all the slack out with you fingers, hold the prop blades and prop hub/closer against turning, and then tighten the nut to take all the play out. When you use a wrench, you only want to apply a light clamping force or it will stretch the aluminum where the threads are and break the shaft.

So tighten it lik 1/8th of a turn and see if the collet slips on the shaft. it if does, only tighten 1/8th turn more and test again. When it will not slip you are done.

If the shaft is highly polished you can take 300-400 grit emery cloth and slide it lengthwise down the shaft to create some small striations on the shaft. That will improve the collets grip on the shaft.

Also, degrease the shaft and inside of the collet with alcohol or acetone or a good degreaser.

Jack

Thanks Jack! I did like you said it and looks like it slipped on all the way this time. Thanks alot!

#9 jackerbes Nov 18, 2012 12:55 PM

OK, l didn't realize it was not going onto the shaft. That is definitely part of the equation on these working well, to have as much of the shaft length engaged as possible.

Good luck with the revival!

That must be a brushed motor, and it probably used NiCAD or NiMH batteries. If you get it going and it seems worthwhile, maybe it will be a candidate for an upgrade to a brushless motor and more modern battery.

Jack

#10 RedLine19k Nov 18, 2012 01:21 PM

looks like one of the kyosho stratus or soarus variations. here's some more info if the op wants to do a conversion. it could definately use more power


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