SP140 Swing arm bolt replacements

I decided to swap out my SP140 swing arm bolts with something with a little more meat on it:

Now, the original bolts seem like they are good grade 12 bolts, so they should be fine.

The replacement ones I picked up have a lot more shoulder and are designed for that shoulder to have things rotate on it so it should be pretty perfect for this. They are a little bit shorter than the provided bolts but do thread all of the way into the nylon lock nuts. If I ordered again I’d probably get the ones that are 5mm longer and some lubricant filled nylon washers. Here’s where I ordered them in case you want to pick some up for yourself: Same-Size Thread Alloy Steel Shoulder Screw but seeing the price of $6.50/each suddenly makes it clear why these aren’t the default.

If any of you have the Iris quick release hub, I also grabbed these bolts: Black-Oxide Alloy Steel Hex Drive Flat Head Screw to replace the ones that were included with the hub because the ones with the hub are just barely too long and will bind up on the motor.

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Can you add a pic of the quick release hub with the bolts that were an issue? I’ve been flying with the bolts it came with and haven’t had any problem with the motor. I wonder if we got sent different ones.

Thanks for the update and doing the research, I got the Iris PPG prop adapter and my bolts screws were binding as well.

I don’t see any reason why not to have the bolts for the swingarms on hand to replace after a while once we start seeing wear indications.

Would you have a link cor the nuts to go with the Same-Size Thread Alloy Steel Shoulder Screw Thanks.

I used the same nylon lock nuts that the original swing arms fit into.

Here’s that photo:

The zinc ones are the original, and I went with black oxide ones for the replacement because they looked cooler.

The original ones worked when they were just hand tight, but when I torqued them down to the 13.4Nm as specified in their manual they ended up binding.

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Since I’m not going to be flying for a bit (I promised the Doctor in my family to not do anything risky for the next month because of the rona), I decided to order the next size up shoulder bolt along with some lubricant filled washers and since I now know that the nylon locking nuts are one-time-use I got some replacement locking nuts.

I’ll update you all once I get them at the end of this upcoming week about how they fit, but to let you all know, I’m a software guy that just happens to watch a little too much This Old Tony. So if you have some actual experience and think you know more than me, you probably do.