Hi... wondering if some people could tell me what you guys do for mounting engines. Basically, do you use bolts with nylon nuts or screw them into the mount, or tap and thread? I have an adjustable motor mount and want to install a TTPro 46.

Thanks for all the info you guys have graciously been giving to all members....
great place,
pete

My prefernce is usually bolts with nylon locknuts

I too use bolts with nylon lock nuts... the instruction for my mustang said to tap and thread the mount but I'm sticking to the nuts n bolts.

I usually tap and thread. There is no mechanical reason for me to do it other than that is what I prefer. I usually put a little blue thread lock when I bolt down the motor.

I also like to tap engine mounts. Many plastic mounts and some aluminum mounts don't have arms that are parallel top and bottom. If you use a nut then it will bend the bolt when it is tightened. That could cause the bolt to break and isn't good no matter what.

For plastic mounts I usually drill all the way through but only tap about 1/4" or so less than the bolt will go in. That turns the mount into a sort-of lock nut.

But if you have a mount that has parallel arms then there's nothing wrong with drill all the way through with a clearance bit and then using a lock nut.

Any time you mount the engine you should check it after the first few flights to make sure everything is still tight. Once the bolts have been tightened 2-3 times they should take a "set" and stay tight. If you're using wood mounts you should continue to check frequently because a wood mount can compress over time which loosens the bolts.

[link=http://airfieldmodels.com/information_source/model_aircraft_engines/mounting.htm]Engine Mounting[/link]