JMR SPecial project. My design.

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Pops

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This winter had been warm enough that we have just got about 6" of snow at one time and everything else has been rain. Not good on our yellow clay grass runway. Not cold enough for the ground to freeze and get hard , just wet and mucky where your shoes sink in.
Not good for airplane 5" tires. Now you know why I had the large tires on the SSSC. I just let the mud and water sling up under the wings and smile and go flying in the wet winters.
So the JMR is setting with its head down wanting to get off the ground and I need to have something to do instead of watching all the old western movies on the idiot box that I have seen before. I have been working a little each day on the Pipe (Mud ) Buggy.
I have 4 VW engines setting on the work table and one for a future airplane, (Maybe a Long wing span SSSC), still going back and forward on trying to decide on making it a flywheel drive of a pully drive. And another is a 1200cc for to power a back up NG Generator for my daughter and grandson's off grid farm. Another is the 1600 cc engine for the Mud Buggy that is ready for the heads installed when I get them done. Worked on the heads yesterday.
 

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Pops

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Taxied the JMR yesterday and the runway clay has finally dried out but the northeast 1K is rough for my smaller wheels, needs rolled bad.
Instructions for the brakes says to have a 2 to 1 ratio on the master cylinders and toe brakes. I have about 1. 75 to 1 and the pressure to operate the brakes is little higher than I like. Plan on fixing the problem in the short future. Will be an easy fix. I like the new Zenith 750 HD nose gear better than the 701 that I had on at first. Handled that rough end of the runway like it should.
 

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Pops

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Finally found a flight instructor to give me a BFR. ( Virus fear ). Found the phone # of an instructor that had given me a BFR back in 1991. Since I have a commercial license he gave me the commercial check ride to see how I would do. I didn't think I did very well and would have failed me, but he said I did pretty good. I got off altitude one time and looked at him and he was smiling. I told him to quit laughing. Said he wasn't laughing, I told him he was smiling very hard, to hard, not to be a laugh :) Had a good time. His BFR's are always fun . So, I'm legal now.

Got the JMR out and during the mag check, now I have over a hundred RPM drop and a little roughness on the right mag. I'll check it out after the weekend. Maybe a plug ? Slick mags has 87 hrs TT each.
 

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Pops

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Finally got the cowling off. Neighbor told me to give him the spark plugs and he will check them out on his large old Champion spark plug machine.
Hope its a plug instead of a bad plug wire. I have lots of extra plugs and a new slick wiring harness is not cheap anymore. But I am :)
Been spending much of my spare time on the rebuild of the SSSC and mowing the spring grass. Darn.
 
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Pops

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Neighbor checked the spark plugs out on his Champion machine. Top plug on #1 , all the rest of the plugs were very good. I have about a dozen extra plugs for the engine , so replaced. Been raining for 2 days and several days ahead. Maybe this weekend to see how it runs.
 

Pops

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Another little problem I want to fix. In post 244, I mentioned that it takes to much pressure to operate the brakes. Going to take the rudder and brake pedals out and do a mod to get the 2 to 1 ratio that I need for a more comfortable pressure in operating the brakes. Last Sat Dallas and I looked them over and decided the easiest way to do it. Will require some welding, so I'll have to take them out of the fuselage, make the mod, repaint and re-install.
 

Pops

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Took time off from working on the SSSC and did some measuring on the rudder pedals and brake pedals this week. Seems like the surplus Bearhawk brake pedals we have is just what I need to get the 2 to 1 ratio. Need to remove my brake pedals and weld on new mounting ears on the rudder pedals to mount the Bearhawk brake pedals. Paint and reinstall.
 

Pops

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Been one year and 2 weeks since the inspection and still haven't went around the pattern yet. Just flying up and down the runway. Hope the fix on the toe brakes to taking normal pressure is the last squawk. To many irons in the fire and the grass is growing to fast.
 

Pops

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Little history of the problem.
On the SSSC I used a small set of hyd brakes and they worked good for the 485 lb EW airplane with smaller 500x5 or 600x6 wheels and tires, but when I went to the 800x6 tires they were a little lacking . Lots of times in flying off runways, you need to taxie with the small wheel off the ground and work the main wheels around the larger rocks,etc, so you need good brakes. So on the JMR with a EW of 680 lbs, I knew I needed better brakes than what I had on the SSSC. I decided to use the Maco brakes and worked out the math on what brakes to use by the instructions on their web-site. Before ordering, I talked to the engineer at Maco and he ask all the right questions and came up with the same brakes that I was thinking of ordering.
I had already built the toe brakes with the same dimensions as the SSSC but decided to see if the brakes would be OK on the JMR with out having the 2 to 1 ratio as called out in the Matco manual. Ok in stopping or slowing down from landing but for hard braking while turning around in a short radius or doing the run up for the mag check, just having to use more pressure than normal.
Guess its called designing for a reason.
 

Pops

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New toe brake's made, welded and painted. I'll take time off working on the SSSC and install the new toe brakes tomorrow. Not much rain for the last coupe weeks and the grass on the 2 acres that I keep moved is growing a lot slower. Have more time to work on the airplanes.
 

Pops

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Wouldn't you know it. Got the new toe brakes painted and installed and been raining for 2 days and looks like I'll just have to wait a couple more days to test the brakes. Runway is wet and soft and the river at the end of the runway is high. Sometimes you get the bear and sometimes the bear gets you.
 
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