Wheel Pant Alignment and Cutout

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6643
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Re: Wheel Pant Alignment and Cutout

Post by 6643 »

6896 wrote: Sat Dec 01, 2018 11:47 pmMy Cleveland kit came with the bleeder screw on the top side for the left side,
How can you tell which one is the left?
6896
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Re: Wheel Pant Alignment and Cutout

Post by 6896 »

I ran into a small issue in trying to use the carbon mounting plates I purchased from one of the club members who made them for me a few years back. I think the 10-32 screw nutplate locations on the mounting plates are designed for the C140 swept forward gear configuration, but my project has straight gear legs. You can see this in the attached photos. I got some dimensions from the plate manufacturer on approximately where to locate the center of the axle on the wheel pant (it should be about 10.5 in from the pant leading edge and 3.13 in up from the bottom of the pant). This centers the wheel in the pant so there is adequate clearance on the front and back. I have confirmed these dimensions myself by blocking the wheel inside the pant. Also, one has to worry about the minimum edge clearances between the upper and lower nutplates. The upper nutplates need to stay below the longitudinal rib on the pant so the head of the machine screw clears it after mounting. On the bottom, per standard practice, there should be 2 diameters edge clearance (3/8 in for 10-32 screw). It looks like to make all this work, I have to drill out one of the rivets on the lower, forward nut plate so I can flip it around and redrill its center. This will allow me to rotate the mounting plate so the gear leg is perpendicular to the pant longitudinal rib. The pant should align with the streamlines in level flight.

In my situation, it looks like I will need to locate the axle center 2.88 in up from the bottom of the pant vs. 3.13 in up. This means the wheel will stick out of the pant a bit more, but there still should be adequate clearance of the wheel between the front and back of the pant. Once I locate the axle center on the pant, then I am set to cut out the inside of each pant to clear the landing gear and brakes.

I set the photos up for the right wheel pant, but the plate is on the wrong side just for illustration purposes to show the issue. It is easier to show the issue from the outside of the pant vs. the inside.

I am contacting the builder of the mounting plates to confirm my analysis.
Attachments
Plate Pattern for Straight Geatr.jpg
Plate Pattern for Straight Geatr.jpg (42.6 KiB) Viewed 4119 times
6896
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Re: Wheel Pant Alignment and Cutout

Post by 6896 »

More photos
Attachments
Wheel Pant & Plate Appears to be Swept fwd gear.jpg
Wheel Pant & Plate Appears to be Swept fwd gear.jpg (75.91 KiB) Viewed 4119 times
6896
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Re: Wheel Pant Alignment and Cutout

Post by 6896 »

Plate has the bottom three holes in line
Attachments
Plate hole line.JPG
Plate hole line.JPG (142.87 KiB) Viewed 4119 times
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Re: Wheel Pant Alignment and Cutout

Post by 6896 »

These photos are what I got for setting up the location of the plates. These are not my pants because I have not made the cutouts yet, but you can see that the bottom #10-32 holes are located in a line the same distance from the edge, which as my prior photos show, would but the landing gear at at an angle to the wheel pants. This is why I concluded that the #10-32 nut plate pattern on the plates I got are set up for the swept forward gear.

Not a problem though as I plan to drill out a rivet in the forward nutplate so I can rotate the nutplate 180 degrees. This will allow me to get the mounting plate set up so the pant is perpendicular to the centerline of the straight gear leg.
Attachments
Pant 5.jpg
Pant 5.jpg (76.81 KiB) Viewed 4118 times
Pant 4.jpg
Pant 4.jpg (64.39 KiB) Viewed 4118 times
Pant 1.jpg
Pant 1.jpg (63.78 KiB) Viewed 4118 times
6896
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Re: Wheel Pant Alignment and Cutout

Post by 6896 »

The Cleveland brake cylinders are symmetrical, so there is no right or left. All I am saying is the one that I chose out of the box for the left gear leg ended up with the bleeder being on the top rather than the bottom
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Re: Wheel Pant Alignment and Cutout

Post by 6896 »

Also, here is a photo of what happens when you try to spray Polyfiber's UV Smooth Prime on too heavy--runs. Six light coats required with sanding between the third and fourth coat. The filler is easy to sand and gives proper UV protection for composite parts. Seal with Polyfiber's EP-420/430 epoxy primer after filling is completed.
Attachments
UV Smooth Prime sprayed on too heavy.JPG
UV Smooth Prime sprayed on too heavy.JPG (127.56 KiB) Viewed 4118 times
6896
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Re: Wheel Pant Alignment and Cutout

Post by 6896 »

0.032 2024T-3 Alclad aluminum doublers for pants. The doubler is used on the side where the long axle nut attaches to the wheel pant with an AN6 bolt and lock washer. I plan to use a doubler on the inside and one on the outside. There is going to be a little extra clearance between my axle nut and the pant so the doubler will help fill the gap.
Attachments
Wheel Pant Doublers.JPG
Wheel Pant Doublers.JPG (147.51 KiB) Viewed 4118 times
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Re: Wheel Pant Alignment and Cutout

Post by 6896 »

Thanks Mac and Ray!
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Re: Wheel Pant Alignment and Cutout

Post by 6277 »

Once again, precise and excellent work. The cylinders are, as you say, symmetrical. If you had chosen the other one out of the box, wouldn't the bleed screw be on the bottom? ;)
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