Neirrh XXL build

Discussion in 'Member Project Logs' started by FritzW, Jun 19, 2014.

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  1. Apr 15, 2015 #61

    FritzW

    FritzW

    FritzW

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    Day 64:

    I got the other side of the firewall face ply glued on. I cleaned up all the squeeze out while the glue (T-88) was still "wet" but I'll still have to run a reamer through the motor mount holes. I'm making aluminum bushings but my spider sense tells me phenolic might be a better choice. I'll glue the bushings in with the firewall mounted to the engine (engine sitting on the bench) so I know everything will line up correctly.

    20150413_194826.jpg This weighs 2.2 lbs, the "Day 61" parts weigh 1.8 lbs. Even if I was going for Part 103 I think I could live with it.

    20150413_194852.jpg I had to fix a small void in the core. I cleaned out the void with a needle file and carved a Maple plug to fill it.

    20150413_194729.jpg I'm making 6061 T-6 bushing because it's fun to do but I'll probably end up using phenolic.
     
  2. Apr 29, 2015 #62

    FritzW

    FritzW

    FritzW

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    Day 65:

    I finally got around to trimming the front of the longerons so I could start mounting the firewall.

    20150428_170040.jpg I had a spare firewall core (rejected due to voids in the inner ply) It's going to make a really nice fixture to locate, and hold the mounting tubes that I'll weld on the front frame. I'll also use it as a drilling jig for the real firewall.

    20150428_170107.jpg I glued some alignment blocks on it so I can take it on and off without having to measure every time.

    Firewall.jpg I clamped the real firewall on for a glamor shot ;)

    20150428_174718.jpg After I drilled out the mounting tube stock the wall thickness is .092". That's going to be fun to O/A weld to .032 wall :/
     
    Topaz, steveair2, Joe Fisher and 2 others like this.
  3. May 24, 2015 #63

    FritzW

    FritzW

    FritzW

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    Day 66: (I'm not counting the three weeks I spent figuring out how I wanted to do this step;) )

    After "over thinking" this with a bunch of retired WSMR engineers (you couldn't ask for a better bunch of friends when your building an airplane) I settled on the best way to mount my firewall.

    20150522_233700.jpg I played with several ways of doing this. BJC had, what I thought was, the best idea: Just weld the tubes tangent to the firewall frame, easy, simple and plenty strong enough. But my WSMR buddies thought it wasn't "1965 NASA" enough and it was decided to go with the "through the tube" method.

    20150523_190241_resized.jpg I drilled 1/8" and 1/4" holes through a piece of square tube to use a drilling jig (worked great)

    20150523_193217_resized.jpg I turned down a pin to index the 1/8" holes in the frame to the 1/4" holes in the drilling jig.

    20150523_205047_resized.jpg It worked like a charm. Once the 1/4" holes were drilled the mounting tubes were just about a press fit in the frame. They're a little long so they wont burn away during welding, I'll trim them when the welding is done.

    ...next: mounting the motor!
     
  4. Jun 13, 2015 #64

    FritzW

    FritzW

    FritzW

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    Day 67,

    I started this project almost a year ago and I've only actually worked on it 67 days and most of that was in the first two months. Now I know why I have a problem finishing projects.

    We got the firewall mounting tubes welded in today but I screwed up the firewall (it climbed the drill bit when I was cleaning T-88 out the bushing holes on the drillpress) ...that's the very first part I've ever screwed up:roll: ...oh well, it only took about an hour to make the first one, and now that I'm an experienced Neirrh firewall maker so I should be able to make a new one in 58 minutes.

    20150612_102420_resized.jpg I never would have started this project if I didn't have an old school Chapter 1 buddy who actually wanted to do the welding.
     
    Abraham Leket and steveair2 like this.
  5. Jul 17, 2015 #65

    FritzW

    FritzW

    FritzW

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    Day 68:

    Well, it took a month but I was finally able to pry the Lazy Boy off my butt and get back to work on the Neirrh. Not much to see but I turned the stock for the 4 main firewall bushings and trimmed the mounting tubes. I also drilled the tubes out to their finished size.

    20150716_181941_resized.jpg The tubes are trimmed but still need to be filed down to the finished size.

    20150716_182044_resized.jpg I just have to cut them to length and drill them out.
     
    Joe Fisher, Topaz, jmt1991 and 3 others like this.
  6. Jul 18, 2015 #66

    FritzW

    FritzW

    FritzW

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    Day 69:

    I got one of the axles drilled today. I knew it was going to be a pain and I wasn't disappointed. The axle mounts on the gear must have cooled too quick after they were welded, it was like drilling tool steel. I used language today that I haven't heard since my Dad was teaching my Mom how to drive a stick shift :gig:

    20150717_164142_resized.jpg There's the mounting tube on the gear (hard as diamond), a spacer and the axle.

    20150717_172244_resized.jpg 20150717_172252_resized.jpg This little drill guide sure came in handy.

    20150717_164229_resized.jpg ...when my wife finds out where the stool for her long arm sewing machine went there's gonna be hell to pay:para:

    20150717_164931_resized.jpg Left side is done!
     
    flyvulcan, Joe Fisher, Wayne and 5 others like this.
  7. Jul 19, 2015 #67

    FritzW

    FritzW

    FritzW

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    Day 70:

    I only worked for a few hours today but it was pretty productive. I got the right gear leg and axle drilled, made a little plate to hold the tailwheel spring on and started to figure out the seat.

    20150718_174550.jpg 20150718_181354.jpg It's amazing how much easier it is to do something the second time. This side went much easier than the other one.

    20150718_185029.jpg With all three wheels properly bolted on (temp hardware) I can start to look at the seat.

    20150718_185256.jpg ...just a daydream shot to keep me motivated

    20150718_185912.jpg 20150718_190016.jpg 20150718_190234.jpg This stuff is very heavy weight, treated, cotton duct (a gift from an Air Force parachute rigging/fab shop :gig: ) It's the same stuff the old Army tents were made out of. I'll have a saddle shop sew it up as soon as I figure out how I want to do it. It's going to be reinforced with Type XXVI Nylon webbing (another gift from the AF) so an average industrial machine probably wont do it.
     
    JimG, flyvulcan, Joe Fisher and 3 others like this.
  8. Jul 21, 2015 #68

    FritzW

    FritzW

    FritzW

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    Day 71:

    It was a dancing banana day. I got to sit in the Neirrh today for the first time! :ban:

    D71 a.jpg D71 c.jpg I read up on Bingelis (canvas seats in Yellow book) and decided to do away with the Nylon webbing.

    D71 b.jpg D71 d.jpg Punched holes, pounded grommets

    D71 f.jpg Laced it up (there's still some Velcro and a few finishing touches that I have to add)

    D71.jpg ...Comfortable, strong, cheap and easy. I'm really happy with it.
     
  9. Aug 7, 2015 #69

    FritzW

    FritzW

    FritzW

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    This isn't much of an update, and I'm not going to count this as a build day, but I think I was able to save my original firewall that was damaged in an unfortunate drill press incident :cry:

    Since it was just the surface plies that were damaged I mixed up some T-88 and micro to make a paste. I used a bolt and some fender washers to squeeze the paste in around the bushing and to align the bushing. T-88 has a higher Fbu than Birch ply so I think this fix is probably better than the original wood. I'll sleep on the repair for a days and see if I like it, if not it's a simple thing to make a new firewall (comments welcome on PM)

    20150723_122647_resized.jpg

    20150723_124033_resized.jpg

    20150723_164630_resized.jpg
     
    Marty59, Wayne, jmt1991 and 3 others like this.

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