JMR SPecial project. My design.

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Pops

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I finished the wiring this week. LED Strobes, LED position lights, electric elevator trim servo, electric oil temp gauge, power for handheld radio. Installed small switch panel under right side of panel.

I'll work on installing the windshield this coming week.
 

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Pops

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Finally installed the 1/8" thick windshield and side glass. I'll wait and see in the test flying if I need any center support for the windshield. Its stiffer than I thought it would be. 28" wide. Everything is done on the fuselage back except for installing the brakes and brake lines. Now I'm getting back on the wings. Need to build the flaps and ailerons and varnish and cover and paint. This is the high cabin model for really tall pilots. The shorter model is 1 1/2" lower cabin top.
 

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Pops

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My buddy 2 hangers away needed to do some welding on his man-lift so we pulled the JMR out of the way. Thought I would take a couple pictures outside where you can get a better picture. Just thinking, maybe it looks sort of like a single seat ButterCup on tri-gear. Trying to get some outside jobs finished before winter, so working on the JMR has slowed down a little. While the man-lift was here I cleaned the ceiling fans and took out the last remaining incandescent bulbs and installed LED's in the hanger. The only thing that is not on solar is the welding machine and air compression. Also installed a new 40 meter Ham antenna in the rear of the hanger and it started raining as we finished.
 

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Pops

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Working on building the flaps and ailerons. The other wing is on saw horses in the paint booth, so will be building for both wings at the same time. I'll build as much as possible before cutting them loose from the wings.

Sorry the picture is a little dark.
 

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Pops

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Making slow progress because I have been busy getting things around the homestead ready for winter. The flaps are about ready to epoxy the plywood skins and I have to install the control horn rib and control horn. Will be using piano hinges on both the flaps and ailerons. Hope to have the flaps and ailerons finished by the first of the year. Then do the coverings and painting and installing the wings on the fuselage. Then I can do the W&B to establish the length of the engine mount for the CG that I want. I usually work on the JMR project 2 or 3 hours a day. Just can go so far and then have to wait for the epoxy to set up. When I run out of clamps, I stop. Doing the flaps and ailerons of both wings at the same time. The other wing is on saw horses in the paint booth.
Also been rebuilding the wood deck on the airplane hauling trailer.
Dan
 

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Pops

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Looking around the shop and found an old pint can that used to contain Poly-Fiber thinner that you get in a practice kit. Decided to use it for my Hydraulic brake fluid reservoir, if Piper can do it on the Cherokee's, so can I. Will mount it high on the firewall. Has some 1/8" brass tubing for the vent silver soldered to the cap and a 1/8" pipe thread brass coupling from NAPA Auto parts store. Silver soldered it to the bottom for the drain, and soldered a tab on each side for mounting. Total cost about $2. Better than the $40 + shipping one from Aircraft Spruce. I will epoxy prime along with the aileron and flap horns.
Did I tell you I was cheap?
Dan
 

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Pops

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Installed the elevator trim tab. 2" extruded alum piano hinge from Aircraft Spruce with .032 2024-T-3 aluminum. The trim tab is powered by the elevator trim servo pictured in post 80. I used a small version of this servo in the SSSC since 2007, very good. I made the tab over size and if its too powerful, I can cut down the width, easier to remove alum than to add. I could have made a trim tab by cutting into the elevator and it might have looked a little better, but I have designed this airplane to be simple and easy to build with the materials used.
I do want the elevator trim tab with enough authority to fly the aircraft so it can be used as a backup elevator control in case of something happening to the elevator cables.
 

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Pops

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I mounted the SS piano hinges to the flaps and ailerons then I needed to drill the holes in the rear spar to bolt the hinge . A C-clamp would not work to hold the flaps and ailerons in place and still be able to move then out of the way to do the drilling. So I made some wooden clamps that worked. Clamped the surfaces in the correct place and swing the surfaces out of the way for the drilling. First I used a 3/16" dia transfer punch to make a good depression in the wood at the center of the hole for a nice true hole with the drill and also used a longer 12" drill bit to make it easier to line-up by sight and held a block of wood on the bottom of the spar for a nice clean hole.

I am using structural screws for mounting the flaps and ailerons. Same as Cessna uses to mount the ailerons on the C-150-172-182. Just a longer grip length for the wooden rear spar.

Now for the varnishing .

Also posting a picture of the bottom of the wing with the fuel tank cover off.
 

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Pops

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I found a mistake in my plans for the flaps and ailerons. I forgot to allow for the gap for the aileron and flap caused by the use of piano hinges. At the root of the wing there are 2 full length ribs 4" apart and at the tip there is a 2" wide rib outside of the aileron to the wing tip. Each of these are about 5/16" shorter than the flaps and ailerons. I had to add on the tailing edges of the 4" and 2" with wood and epoxy/micro-balloons
filler.
Now I need to correct the plans


I thought I made a mistake onetime but I didn't :)
 

Pops

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I have been varnishing, varnishing and varnishing. Lots of area to varnish in a geodetic wing. I need to go through my covering supplies and see what I need to order for the covering. I have all the Poly-Fiber paint that I need for the wings.
Ordered a wood Prop from Culver Props last week. After talking to the old man (Pops) at Culver Props last summer, we decided on a wide blade 68"x48", ( 70"x48" cut down to 68" dia). 68" dia is the longest prop that I can use and have the proper ground clearance with a flat nose gear tire and the nose strut fully collapsed. This is a smaller airframe for the Cont-85 engine. Cruise at 2400 rpm should be about 100 kts with about 1200 fpm ROC. Also thinking about a 2.5 or 3" prop extension to make the nose bowl more streamline and better looking.
Hope to find out this summer on the cruise.
 

Pops

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I finally have one wing, both flaps and both ailerons ready to cover. I have the varnishing at about 75% on the other wing panel. This is the third set of geodetic constructed wings that I have done and the varnishing of all the strips is the worse part of building this type of wing. I can see the distant glimmer of sunlight over the horizon.

Dan
 

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Pops

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Please Mr Custer do I have to cover all of that beautiful wood?
I always enjoy the fabric covering and painting. That's when it starting to look like something is getting done. Can't wait to get the wings bolted on the fuselage and do the W&B and work out the length of the engine mount and install the engine.
When I do the first engine start-up I'm going to run around the hanger and holler as loud as I can " IT'S ALIVE, IT'S ALIVE".
You don't have to tell me, I'm a few marbles short. My father always said it runs in my mothers side of the family, but he was wrong.
Dan
 

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Pops

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I weighed everything and with a normal covering and painting on the wings, it looks like IF I keep the weight of the nose bowl, cowl and seat cushion down to a total of 15 lbs I'll make my 600 lb empty weight with a GW of 1050 lbs. Love it when a plans comes together.

Dan
 

Pops

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I think I can squeeze in a 8" Tablet in my panel along with the 7" with Avare. Plan on using Talos flight instruments on the 8".

Also put the first coat of Poly-Brush on the right wing today. Now to rib stitch.
I'll work on this wing until the Poly-Spray is finished and then do the left wing to the Poly-Spray.
Then the final color coat of each wing.
 

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Pops

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I must be getting old or something. I'm a lot slower rib stitching than I used to be. Used to do a wing panel in about 6/7 hrs. As you can see I've started rib stitching and looking at the needle sticking up can you tell me what rib stitch I am using, OK, I will tell you, its the Beech rib stitch knot. It always was a little easier for me, I didn't start to tie my own shoe strings until in the first grade so I'm a little slow and need all the help that I can get :)
Laying out the rib stitching on a geodetic wing is harder than other wings because of all of the strips getting in the way. As you can see towards the front the stitches are closer together, the main spar and strips were in the way so I had to use what opening that were available. I have one rib stitch spacing for in the prop blast area, another from the prop blast area to the end of the control cables area and another to the end of the wing. Some days you get the bear and some days the bear gets you. I have the wing hanging on wires so I can flip it myself when needed. Not needed rib stitching but will be needed when painting.
So, in a couple days this wing will be ready for more Poly-Brush and Poly -Spray and I can start on the other wing.
 

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