Cowl hinge securing clarification needed

I'm trying to decide how to secure my upper and lower cowls. I've looked at a lot of posts and discussions about this but I still have some questions.

For those of you that have used a pair of cover plates on either side, what is going on under these plates? Is the pin coming through a slightly enlarged slot between halves? I would think that to do this, you would have to line up the eyelets with the slot which would be visible from the sides of the aircraft. Not preferable.

So, to correct this, you would shift the hinge up or down slightly but that would mean a larger hole would need to be carved out under the plates to allow for the offset of the pin. Is this what all are doing?

Are the pins secured to the plates at all or just floating around on their own? I suppose this can work since the plates are blocking their exit from the hinges.

I'm also kicking around a homemade Carbinge type system using an Allen screw.

Thanks

Hi Kelly...

....if the cover plates you're talking about are the small plates in the forward area of the cowl split line on either side, they're simply hiding the hole through which the hinge pin is removed. Some guys get really creative with skulls, half dollars, etc for plates.

The pins don't move so no worry about them.

Regards,

One Way....

ArVeeNiner said:

For those of you that have used a pair of cover plates on either side, what is going on under these plates?

Click to expand...

I opened the hole large enough so the cowl hinge pin can be easily reached with a pair of needle nose pliers. What is not immediately apparent in these photos is that the .125 thick cover plate that I fashioned is also bent to conform to the cowl curvature. Each screw is attached to a nutplate affixed to the cowl hinge half opposite it. Because of the horror stories I've heard about hinge pins working loose and trashing a propeller, I gave the location a bit of additional thought. Because of where I chose to terminate the hinge pin and install the cover plates, there is virtually no chance the hinge pin can migrate. Even if there was no cover plate to hide the open hole, at worst the pin could only move forward an inch or so...and it would still remain safely captured inside the cowl.



Here is a scrapped cover plate I discarded for one reason or another. The curve is obvious. It was easily formed by securing the cover in a vice, then thwacking the tip of it with a rubber mallet.

I tried to do what Rick did in the previous post but I could not get a good fit making them out of Aluminum. So I made some fiberglass plates that I molded in place.

My glass ones are not a sharp looking as the one's Rick made but they accomplish the same task.

There was a thread a while back called something like The Good, The Bad and The Ugly that had many examples pin securing methods.

Another option is to insert the pin from the cabin area, using a guide tube that gets things lined up inside the FW.

Just extend the tube so the end of the pin is easy to reach without having to crawl under the panel.

Thanks for the info everybody!!

Here's some good ideas too, taken from w1curtis.

Phil


http://wcurtis.nerv10.com/HingePin/index.html

Cowl hinge pin RV-6

I'm not sure how common this technique is. The builder design it into the vent and with a 90? bend 3/4 inch long that plugs into a hole to lock it in place. It works very well. I will Email you a picture.

Tony