Posted for "William Rumburg" <lancair403@verizon.net>:

> John -
>
> There's an easier and more elegant solution:
>
> The Lancair-supplied middle gear door attach bracket is unnecessary. I never
>installed mine because the bottom of the door can just as well be attached
>directly to the casting and you'll gain at least 1/8" closure in the process.
>You can check this in advance for your own situation, however, by removing
>the door and attach bracket. Retract the gear and hold the door in place to
>verify that it then fully closes; if it does, proceed as follows -
>
> 1) Drill and tap the casting for 1/4" holes near the bottom of the door,
>about 2 or 2-1/2" apart (see photo 1644)
>
> 2) Install short 1/4" studs in the holes. Retract the gear and, holding the
>door in the exact desired position, press it into the studs to mark the
>location to drill for new holes in the door itself.
>
> 2) Create a local hard-point in the door at the attach screw area by using a
>1-1/2" piloted hole saw to remove the inner skin and foam core (Do Not remove
>the outer skin). Prep and fill the circular area with a thick resin/flox
>paste (you'll also have to fill the holes previously used for the attach
>bracket)
>
> 4) Retract the gear and hold the door in the exact desired position, again
>letting the studs again mark the hole position. Drill for the new 1/4" attach
>screws and tinnerman washers - the aft end will require a couple of washers
>between the door and casting and that will allow for some adjustment of the
>door against the fuselage. Use nylon washers against the door at all
>locations (see photo 1643)
>
> My middle gear door installation is "solid as a rock"
>
> Bill Rumburg
> N403WR  (Sonic bOOm)
>
> ----- Original Message ----- From: "John Cooper" <snopercod@comporium.net>
> To: "Lancair Mailing List" <lml@lancaironline.net>
> Sent: Saturday, June 07, 2014 11:15 AM
> Subject: [LML] [LNC2] MLG tires hitting upper wing skin
>
>
>> After replacing the original Rosenhan brake calipers that came with my L-235
>>with new Matco B5-4 units, the tire now contacts the underside of the upper
>>wing skin just before the gear is fully retracted. As you all know, the brake
>>mounting plates fit between the aluminum gear casting and the axle. The old
>>Rosenhan die-cast brake plates were .210 thick. The new Matco brake plates
>>are only .125 thick, so I had to add shims between the casting and axle to
>>keep the brake disc properly "centered" between the brake pads. On my latest
>>installation, the distance between the gear casting and the axle is now .310,
>>which extends the wheel and tire out .100 more than before. The gear door is
>>probably only .060 away from closing when the tire hits the underside of the
>>upper wing skin, so the addition of the shims seems to have caused the
>>problem.
>>
>> I originally had 70 PSI in my Cheng Shen MLG tires and bled them down to 60
>>PSI but that didn't help.
>>
>> Today I will attempt to reduce the thickness of the shims, but I fear that's
>>not going to work because the new Matco brake pads are thicker than the old
>>Rosenhan pads and need more clearance to allow for wear.
>>
>> So the only options I can think of at this point would be to 1. carve out a
>>crescent of the upper wing skin core where the tire it hitting, 2. grind down
>>the ridge on the tire where the tread meets the sidewall, 3. Reform the
>>middle gear door, or 4. fly with the aft edge of the middle gear door about
>>1/16" away from being flush.
>>
>> Has anyone run into this problem? Any suggestions?
>>
>>
>> --
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