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JMR SPecial project. My design.

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Pops

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Building an aircraft of my design, JMR Special. Single place, LSA, for a large pilot of 6' 4" x 250 lbs. GW- 1050 lbs, WE-600 lbs, Wing span-28', Wing area- 109 ft2, Steel tube fuselage , Wood wings with flaps,(working on designing an aluminum set of wings). Airfoil-- 2413. Majoring the C-85-12F engine for it.
It has a little of the Tailwind look. Trying to made it as easy to build as possible.

Just having fun. Dan
 

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Pops

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More pictures of the JMR Special. Will have wing fuel tanks for a total of 20 gal.
Dan
 

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Pops

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Worked today in assembling the experimental Cont-85-12F engine for the JMR. Will not be using an electrial system. Just a 5 amp battery for a handheld com and gps. Picture of the C-85 engine. Dan
 

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Pops

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I got the engine together today. All the ribs are made and the spars are ordered for the wings and they should be here in a couple of days, so I will be starting to assemble the wings shortly.
Pictures of the C-85-12F with the starter and generator removed. I did clean and polished the inside of the carb spider and the intake elbows for less restricted flow. Not really a major overhaul. This was a mid-time engine off a Cessna 140 and I balance the rods and pistons, honed the cylinders with new valve guides and valves, valve springs and rings. All new main and thrust bearing, rod bearings. Measured everything for wear. All new gasket, seal and rubbers. All new bolts and nuts for the complete engine. Both Slick mags just have 200 hrs on them. Have to overhaul the carb yet. Also plan on making a custom aluminum oil tank to save weight. The heavy brass crankcase fitting on the front right of the engine weights 5.1 oz. Ordered a replacement in aluminum to save most of that weight . Dan
 

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Pops

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I finished up the baggage compartment storage box. It has a door in 1/2 of the bottom to inspect the controls and to install a battery if I need for W&B. Couldn't make it any wider because of the pushrod for the flaps that will be coming up each side. Also couldn't make it any deeper and still remove it. One bite at a time. Dan R.
 

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Pops

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Been working on running the fuel lines. I have two fuel outlets from each tank wing fuel tank, one in the inside rear and the other on the inside front. Nose up or nose down you can't un-port a fuel pickup. Have the lines coming together then a valve for each side. I have the same system in my little single place Super Cub and I like it.
Ran out of the correct fittings so had to order more. Just like a plumbing job, you need the whole store because there is always something you need and don't have.
I'll work on the Bearhawk until the parts arrive. Dan
 

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Pops

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Today I found the amount of weight of lead I need for the elevator counter-balance. 2 lbs- 2 oz per side. Now I need to temporary tack some light metal on the elevator counter-balance area to hold the molten lead as I pour it. When I am finished, I will post pictures. Dan
 

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I finished pouring the lead for the elevator counter weight. C-clamped some scrap .032 steel on each side and mounted the elevator in a vice, pre-warmed the steel with a torch and poured the lead by melting it with the torch. Also used some scrap metal and made a small funnel. Took 2 lbs and 2 oz for each elevator for a slight over weight allowing for the weight of the paint and fabric. I welded tabs with a 3/16" hole on the inside of the 3/8" tube at the tip of the elevator to lock in the lead weight. Will also drill a hole in the "C" channel rib for a screw. With the lead inside the "C" of the rib, the lead weight will be firmly mounted.
Another day of fun with the wood burning stove going good and watching it snow all day outside. Dan
 

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Pops

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So the fuselage and tail surfaces are ready to cover. I have all the wings parts made except needing to put the plywood doublers on the spars and drill holes to bolt on the fittings. Been making the wing strut ends from 2024-T3 aluminum. I was not firm in my mind about the wing tips, so I decided to go with the Wittman Tailwind type of tips.
Picture of some of the wing strut fittings. Dan
 

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Pops

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Have the plywood doubler on the spars and all of the fittings made. Now to drill the spar for the fitting and epoxy prime all the fittings. After that, I can start putting the wings together. I need to do some arranging in my shop to make room for another build table. I need to start putting the Bearhawk wings spars together at the same time.
 

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Starting to skin the doors. I sandblasted and epoxy primed the doors last Sat. Will use pulled rivets leftover from the Zenith 601 build. Tomorrow I will work on the alum skins that surrounds the windows. As soon as I get my 1981 Chevy pickup out of the paint booth, I'll be ready to start covering the fuselage and tail surfaces. Need to order some more T-88 and start epoxying the ribs to the main spars that is on the build table. Dan
 

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Pops

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Finally finished the left door. Had my short wife to try to take some pictures. Lots of room for a large man. I am 6' tall and 225 lbs and feel almost small in the cockpit. I don't know who that old man is that is in the cockpit but he looks like a dead ringer of my grandfather when he was my age :)
Dan
 

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Pops

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More pictures to show the size of the cockpit. If you are 6' 4" X 250 lbs, you will fit. 600 lbs EW with a 1050 lbs GW. I plan on getting the fuselage and tail surfaces covered and the wings assembled this winter.
Dan
 

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Pops

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Finally starting to put the first wing of the JMR Special together. Will be geodetic construction. These wings are rated at 6.7 G's .

You will also see the 2 Bearhawk projects in the pictures. The Bearhawk beside the work table is mine and the other belongs to an old friend on mine of 40+ years. During the winter we work a couple days a week on our Bearhawks.

Dan
 

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