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I am missing the reverse thread nut that fastens the Optima limiter gear. Does anyone have a good online resource for finding these type of nuts? Am having a hard time finding a replacement. Thanks.

I think Your best shot would be a hardware store or an old model aviation shop that carries Graupner or Robbe spares.

You use a M2,5 polyamid nut and force it on.

German ebay has a set of M3 links and rechts mutter, one of each, but this is not lock nuts.

Or You could buy a M3 links gewinde tap (reversed thread) at the german ebay.

I´ll check my local hardware store monday and see if they stock any reverse threaded lock nuts.

Don't force a metal nut on there because the shaft will break If you can't find anything, the best thing to do would be to use a nylon nut (losi 4-40). The nylon ones from kyosho are too soft (and small) and may not hold. The PRM versions may work as well.

Polyamid is plastic

@DennisM, @Highwayracer

Thanks for the ideas guys. I hadn't considered a nylon nut. Can't seem to find the reverse thread M3 nut anywhere, even specialty shops.

They are not nylock... but

http://neweramodels.mybigcommerce.com/3mm-threaded-turnbuckle-nuts-set-of-six-6-pairs-total-of-twelve-12-nuts/

https://www.fastener-warehouse.com/product-p/293550.htm

-still searching-

Chris

McMaster Carr has some left hand nuts
http://www.mcmaster.com/#left-hand-threaded-finished-full-hex-nuts/=oiyrom

http://www.mcmaster.com/#left-hand-threaded-hex-nuts/=oiytu8

You can alway take a normal nut and deform it just a bit to make it a lock nut.

highwayracer wrote:Don't force a metal nut on there because the shaft will break If you can't find anything, the best thing to do would be to use a nylon nut (losi 4-40). The nylon ones from kyosho are too soft (and small) and may not hold. The PRM versions may work as well.

x2 best bet for sure IMO.

Hey thanks for those links. Will check them out.

Appreciate all the great ideas guys. Just trying to get the nut so I can use the part.

One thing I forgot to mention is that the RPM nylon nuts aren't threaded. They can be used for 4-40 or 3mm in either standard or reverse thread

I have an ot-74 limiter gear, and its fixed with a philips head screw. Is this not the same gear set? Were there different productions of the same part?

There were a few variations of that shaft and gear

That doesn't sound right; there should be a threaded shaft protruding through the limiter gear, with the gear attaching with a gold-colored reverse-threaded nut. The original Optima gear (not the Turbo's OT-74 Limiter Gear assembly) is just a sold single part with the gear fused to the shaft, so no nut or screw. Also note that there are 2 kinds of OT-74; some had a thick, beefy spring while the other had 3 or 4 little spring-washers. They did the same thing but I've heard the beefy spring one was the better one.

More discussion on this gear setup is here:

http://www.rc10talk.com/viewtopic.php?f=30&t=17162

I've never owned the OT-74 with the spring-washers, though...only the thick spring kind.

Pics stolen from eBay

Ahh, go figure, that's the variety I never owned, and the pic I found of it only shows the side view.