Cowl Fit Problem -- fixed pitch RV 6 to constant speed
So we finally got to mounting the new hartzell CS prop.
We then held our breath while fitting the upper and lower cowling.
Dang, not enough clearance from the spinner backing plate to the cowl. Actually, there was no clearance.
Our expert EAA advisor is saying in a perfect world, we need 3/16' spacing between the cowl and the spinner backing plate. Agree.
Here are the three possible solutions:
1. Cut off the front of the cowl about 1/4 back. Trim 1/4" from the upper and lower cowl front, and then re-layup the front of the cowl.
2. Cut off 1/4" from the back of the cowl( essential the piano hinge and other dsuz fasteners.
3. Remove the 3/16" spacer separating the prop hub from the spinner backer plate. The would move the backer plate forward 3/16". We would then also move the mid spinner attachement plate also forward 3/16" by moveing the 3 x 1/16" washers to between the prop hub and the mid spinner attachment plate. We will also have to remove some more material from the backer plate, so the plate will not rub against the prop hub as it gets 3/16" closer to the hub.
You can see the spacer in this picture:
This last possibility is likely how we will proceed.
I appreciate any and all comments, especially if there is a better way.
So we finally got to mounting the new hartzell CS prop.
We then held our breath while fitting the upper and lower cowling.
Dang, not enough clearance from the spinner backing plate to the cowl. Actually, there was no clearance.
Our expert EAA advisor is saying in a perfect world, we need 3/16' spacing between the cowl and the spinner backing plate. Agree.
Here are the three possible solutions:
1. Cut off the front of the cowl about 1/4 back. Trim 1/4" from the upper and lower cowl front, and then re-layup the front of the cowl.
2. Cut off 1/4" from the back of the cowl( essential the piano hinge and other dsuz fasteners.
3. Remove the 3/16" spacer separating the prop hub from the spinner backer plate. The would move the backer plate forward 3/16". We would then also move the mid spinner attachement plate also forward 3/16" by moveing the 3 x 1/16" washers to between the prop hub and the mid spinner attachment plate. We will also have to remove some more material from the backer plate, so the plate will not rub against the prop hub as it gets 3/16" closer to the hub.
You can see the spacer in this picture:
This last possibility is likely how we will proceed.
I appreciate any and all comments, especially if there is a better way.
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