I went to the feild tonight and the spinner and prop fell off, now I need to replace the nut that holds the prop on. Can some tell me if they know the nut size. Its the OS FXi 46. The hobby store is closed all weekend so I hope I can get it at a hardware store.

Thanks for any help.

Justin

You don't want to buy one at the hardware store unless you can find a steel nut. The hardware that you can buy at the hardware store will strip out as you tighten it down.

Ken

The prop nut and prop washer that come with the engine are EXTRA hard so they can take the tightening they need to NOT come loose like yours did. USUALLY the parts are caught inside the spinner when they come loose but you need to be careful not to drop in the grass or let them fly away. Check with your LHS and get the correct parts. Part numbers are in your engine manual.

Fotr the weekend - I believe it's a 1/4 x 28 nut.

1/4-20 prop nut: http://www2.towerhobbies.com/cgi-bin...?&I=LXCT54&P=Z
Washer: http://www2.towerhobbies.com/cgi-bin...?&I=LXCT71&P=Z

Like the other guys have said, be careful buying something at the hardware store. Most of what you'll find there is very soft. The threads in the nut will distort or strip and the washer will bend. This could possibly lead to the prop coming off and hurting somebody. If you have a fastener supplier or hardware store in your area with a good selection, you may find a hardened nut and washer but I wouldn't try it unless you were absolutely sure.

I still have the washer, just cant find the damn nut!!, I just want to have a nut to fly on sunday, untill after the holiday and get down to my LHS on Tuesday for the proper one!

Justin

Know anybody who won't be flying? Most engines in the .40-.50 range from various manufacturers use a similar hardened 1/4-20 nut. Maybe you could convince them to cough up the nut until you can get the replacement. I know exactly what you mean about it being the weekend and wanting to fly. I've been up until 2-3AM on Friday several times so I can have something finished in time for the field the next day.

Don't freak... Forget every one above. You should be able to get a steel washer that WIll work at a Car parts store (ie. O rielly , Pep boys.) ; If it's strong enough for car purposes It will work for your plane. (I've tried it) If they aren't nearby you can try Home Depot... Before you think their nuts won't work... look for steel nuts I'm positive they have them. As far as the size Just measure it in mm and then with the ruler you bring to either of the stores measure the inside of the nut. Worst case scenario you have to buy 2 50 cent nuts because you can't tell wich one it is.

Good luck
Electrolight

PS Try a car shop first (they are however more expensive ( it might be 60 cents a nut))

Go with a Grade 8 nut and you`ll be fine.

If you are not quit sure on the hardness, put two nuts on - washer then one nut then tighten the other nut on the first one.

hobby world is open on the weekend

at leat it should be

what has changed??

GRADE 8 will get you by for the week end. I like alum hubs 'cause I can see the beggars and they don't pop off as easily.
I believe there is a force that effects plastics hubs (pains in the arses) I believe it is related to the force that trailer parks have on tornados????[:-] good luck and happy flying.

Electrolight, go back to electrics. The prop nut needs to be a strong steel, Grade 8 is fine. A standard hardware store nut is usually mild steel that may not tighten properly and might cause your prop, washer, AND drive washer to fly off in flight. Then you'll be in a real pickle. Not only might you lose a prop, but the driver washer as well. Also, it might fail at just the wrong time, like right after takeoff. The extra RPMs the engine turns after the prop comes off won't do it any good, either.

Don't skimp pennies in this hobby. Don't risk your engine or plane on a twenty-five cent part just because you just gotta fly this weekend. Use the right stuff.

Overkll? Maybe. Overly cautious? Possibly. But there are risks, and there are foolish risks.

Dr.1

An auto parts store should be able to provide you with a useable prop nut. Automotive nuts are usually heat treated to various levels of hardness depending on where & how they are used. Also the pitch diameters vary for the same reasons. I believe Insanemoondoggie is correct about #8. ALSO, make certain the thread is correct 1/4-28 versus 1/4-20 or 5/16-24 versus 5/16 - 18, or for that matter not metric, as they are close in size. A hardened nut of incorrect pitch when forced onto a th,d crank shaft will probably have you replacing the engine c/shaft.

Fredsedno