Electric flap weldement “play”

[nohoflyer]

Final post on this….

Well third install was a charm. I spoke to builder support for some other ideas.

1. I both sanded the weldement and the blocks a bit.

2. I loosened the torque on the attachment bolts. Vans said the normal torque values are for securing metal and in this case we are compressing plastic and that some distortion may occur if you crank on the nuts. So I backed off a bit.

3. Used white lithium grease on the ends and the blocks.

The end result was a much smoother movement. After reading some posts on flap motors going bad I had a bad feeling about all the friction. Thanks for all the suggestions !

[grayforge]

Originally Posted by nohoflyer

Final post on this….

Well third install was a charm. I spoke to builder support for some other ideas.

1. I both sanded the weldement and the blocks a bit.

2. I loosened the torque on the attachment bolts. Vans said the normal torque values are for securing metal and in this case we are compressing plastic and that some distortion may occur if you crank on the nuts. So I backed off a bit.

3. Used white lithium grease on the ends and the blocks.

The end result was a much smoother movement. After reading some posts on flap motors going bad I had a bad feeling about all the friction. Thanks for all the suggestions !

This is the exact info I was just looking for: I find that torqueing bolts through UHMW plastic blocks tends to distort the blocks. Good to hear that we can go lighter on the toque.

[swisseagle]

UHMW cant be opened up with emery cloth ...
The hole in the UHMW are not absolutely round ...
The tubes are not absolutely round ...

Suppose the largest diameter tube comes onto the smallest plastic diameter during the partial rotating and vise versa. high friction is generated.

Measure the tube and plastic work with the emery cloth on the high-points of the tube and on the smallest positions of the plastic (but also on the tube).

Plastic should not be lubricated with mineral oil-based lubricant! It will swell the plastic (with time), look for a special approved plastic lubricant.

[JonJay]

UHMW is self lubricating. If your weldment is binding or has a high friction component, fix it. Lubricating is just masking the problem and sets up another maintenance item.
These journals should be maintenance free for life when properly fitted.

Also, those flap motors are geared and a lot more powerful than one thinks. I haven’t heard of a flap motor failure due to overload. The common failure used to be grease migration interfering with the commutator in the motor.

[kentlik]

Mine were tight as well.
In a previous work situation, we used a lot of Delrin(UHMW). You can sand it but it just makes it grow hair and often makes the issue worse. I don't like grease either.
Reduce the torque on the bolts.
If you find it is binding address that first and if you still need a little help add some graphite. I wouldn't use anything that attracts particulate, like grease myself.

My $2 worth of advice.