Return to REVIEW Page

HOW TO INSTALL A PROPELLER

By David Teer

When installing your prop, special techniques must be employed. Just tightening up the prop bolts one time won't do it! You will lose your prop on the second or third flight otherwise! When you lose your prop, you lose your spinner too!!

Proper procedure for tightening prop bolts:
1) Obtain thin steel washers and place them under the heads of the socket head screws. The heads of the socket head screws without the washers will gall the aluminum spinner hub and will prevent full tightening of the socket head screws.
2) Tighten the screws a little at a time. Tightening one screw as much as possible without the others being tight will cause uneven pressure on the prop hub. Tighten one screw some, then go to the screw 180 degrees from it and tighten that screw. Go around and around several times. Don't over tighten so that you crush the prop.
3) Fly the plane for 5 minutes. You can leave off the spinner cone (of course have the back plate in place).
4) Land the plane and retighten all the prop bolts. (Not too tight!)
5) Fly a standard length flight.
6) Retighten all the prop bolts
7) Fly one more time
8) Retighten all the prop bolts. If they don't move this time (they should not). Then you have two options: a) leave it alone or b) remove one screw at a time, put on some very light thread locking compound (not too strong!), and reinstall the screws one at a time. It is not necessary to use thread-locking compound, but if you lost a prop before and now you are jaded, this is your extra insurance.
9) Check the bolts every once in awhile, though the prop should never loosen if you followed the above procedure.


HOW TO INSTALL (& REMOVE) A CF SPINNER

When installing your CF spinner, special techniques must be employed. Just tightening up the screws won't do it! You will lose your spinner after a few flights otherwise! If you over tighten the screws, the spinner cone will come off leaving CF donuts under each screw. When you lose your spinner, you may damage your propeller too!!

Proper procedure for installing the spinner screws:
1) Install the spinner cone after you have completed the installation of your propeller! See how to install your propeller first!
2) The spinner screws are 4-40 button head screws, which use a 1/16" allen wrench. If you replace these screws with 4-40 socket head screws you will use a much larger 3/32" allen wrench. The larger wrench allows for higher tightening and (more importantly) higher loosening forces. The socket head screws do protrude up so you may not like the appearance. Socket head screws are not required! It just makes things a little easier.
3) Install the spinner cone and be sure that it does not touch the propeller. There is no need for balancing the spinner cone. Follow the HOW TO CUT YOUR CF SPINNER instructions (below) if you have interference.
4) Install all 6 screws about 1/2 way.
5) Tighten all screws very gently.
6) Remove each screw one at a time and use a very light thread-locking compound. Do not use RED!! Tighten, but not too tight or you will crush the CF. If you crush the CF, the cone will come off leaving donuts of CF under all the screw heads. It's not easy to over tighten the button heads, but it's very easy to over tighten the socket heads.

Proper procedure for removing the spinner screws:

1) Assuming you have screws installed with thread locker, then heat an allen wrench red hot with a propane torch.
2) Insert the red-hot allen wrench into a screw. (Don't slip and touch the spinner!!)
3) Apply light pressure on the screw to loosen the screw. It will take 5 seconds for the heat from the allen wrench to transfer to the screw. The heat will loosen the thread locker and the screw will come right out.

Proper procedure for removing stripped spinner screws:
1) Assuming you have tried removing screws held in with thread locker and stripped out the allen head screw, first cut a slot in the screw head with a dremel.
2) Using a propane torch, heat a flat blade screwdriver, which fits into the slot you just, made.
3) Insert the hot screwdriver into the slot and apply pressure. When the screw moves out a little, immediately remove the screwdriver to stop heating the screw.
4) The screw should come out normally now that it's loosened.
 


HOW TO CUT A CF SPINNER FOR A PROPELLER

When cutting your spinner, special techniques must be employed. CF does cut pretty easily, especially compared to aluminum! There are two methods. One is to ask me to do it for you, the other follows. :))

WARNING: When you are cutting CF, don't get the dust on you. Especially don't breathe it. Do it outside even if you have a vacuum cleaner! While it won't kill you, your skin will itch and drive you nuts! If you breathe it, you will cough for the rest of your life and you will want to die! REALLY!!

1) Bolt the propeller in the proper position to the backplate. You will need a 10mm bolt about 75mm long. Rotate the prop so that the trailing edge (TE) is just a tad in front of the screw tabs. See below.

2) Mess around cutting a piece of heavy paper so that it looks right on the prop. Leave a little gap. See below.
3) Mark the position of the forward mounting screw on the paper as shown below. You will use this mark as a reference to transfer the slot to the correct position on the spinner by putting this mark onto the hole in the spinner cone. See below.

 4) Transfer the slot onto the cone using a heavy black felt marker. Don't screw this up! :)) See below.
 


15) Get a rag, a dremel with the two different sized sanding drums (9/16" and 5/16"), and a fan. Go outside and set up the fan. Hold the spinner in the wind of the fan and use your large drum, grind away! Wipe the dust off the spinner with the rag every so often so that you can see what you're doing.
16) Once you've ground up to and including the line (using the small drum sander if necessary), then test fit the cone onto the backplate with the prop bolted to it. Fit and sand and shape as necessary to get an even gap all the way around.
17) Order new cone and try again.


It's actually not that hard. It should take you about 2 hours the first time and 30 minutes the second time.

Thanks