a couple printed widgets

[A2022]

seatback tray updated analysis...... I doubled the number of nodes and did another thing to reflect the model detail to achieve a more accurate result. 900K nodes and needed to run overnight. a common practice is to make an FEA model and review the results and then double the elements and look at it again to understand the stress concentration areas better. the refined model stress is 10% higher and within limits. looking good.

these elements have mid-side nodes that improves accuracy.

analysis for ultimate 20 lb loading. this would be when the tray is loaded with 3.3 lb and pulling 6g.















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from somewhere in the mountains, to see a 3D printing guru by the firelight, spooky. Luke, you must feel the force. .... not as fast as an RV

[A2022]

seatback storage tray..... day 2, 20 lb load test. well, I screwed the pooch and forgot to remove the lead weights before today's flight. I did a couple zooms and it was moderately bumpy. the landing was OK. I remembered the lead was still in the tray about halfway into the flight. however, everything was still there in place when I got back. there's another data point. I don't know if I should remove the tray now for inspection now or wait.

[A2022]

seatback storage tray....day 3, I left the tray in place and inspected around the edges. looks good. unload the tray and went for a flight then reloaded the tray with the 20 lbs. everything is in perfect condition with this ultimate loading so far. load testing is ultimate 20 lb loading. this would be when the tray is loaded with 3.3 lb and pulling 6g. I am becoming faster at loading and unloading the lead weights.

Govi, Sails of Joy
https://youtu.be/Z5rrmPDGuWM

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Smoky Mountain Half Marathon getting close and I'm getting pumped.... a beautiful place to run!

hitting 50 pushups per day after a run.

the plan is same as last year.
1. fly there
2. eat like a pig to carbo load
3. run and win the race for my age group (60-64), but little chance of that because there are some world class runners there but hoping for a top 5 place
4. recover and eat like a pig
5. fly home

from what I have found, when you show your race results to the doctor, it sure is easy to get signed off for a medical.

[A2022]

seatback storage tray..... day 3,4,5, 20 lb load test. day 5 I went for a flight and forgot to remove the weights again. this tray is getting a workout. prefight check was good, but I don't have this in my routine, I need a sign.

[A2022]

seatback storage tray..... day 6,7, 20 lb load test. day 7 unload, fly then reload. tried to get some photos of the high stress corner areas. no signs of distress on anything. everything is tight and secure. August in Ohio has been wet, everything is green. Low temp tonight is 15C so it's beginning to become very nice weather. the world is beautiful from up there. que the music. Nothern Cincy airspace is normally busy but not tonight, I had the sky to myself after the last student landed at HAO.

Ben Böhmer - Purple Line (Original mix)
https://youtu.be/r6s6K-b1QkQ

[A2022]

rudder gust lock using a bungee with a rope limiter. I'm still thinking about what sheathing to use for this. obviously, this one is too big. need to look for something else. this concept may work for a taildragger, where some allowed motion is provided by the bungee. the rope limiter can be set to any dimension as a hard stop.

[A2022]

seatback storage tray..... day ?, 20 lb load test. day whatever, I'm losing count. unload, fly and reload. hey, lifting 20 lbs into the cockpit is heavy. another seatback tray printed in dark grey this time.

The Dualz - Your eyes (Live) /// Anjunadeep
https://youtu.be/bu4AP-HQWbU

[A2022]

thinking about an exterior acoustic hush panel for the exhaust pipes to keep noise and vibration outside the aircraft. I may attach it with velcro. but I don't want air to get under it, however. I will probably have to make this from two pieces.

[A2022]

in-process parallel printing some brackets. if you print using this method, it is good to have the printed parts close together to minimize travel moves.

Tinlicker - Rebirth (Ft. Hero Baldwin) [Official Video]
https://youtu.be/owNOQeplt0Q

[A2022]

ABS complex part. printed well in a heated chamber. ABS is a good printing material if you can exhaust the fumes.

[A2022]

seatback bar storage tray.... 3 weeks of ultimate static load testing (20 lb). it's looking good. I'll let this run for a month. unload, fly, reload. a beautiful calm day (with music)! the sky is normally busy around northern Cincinnati, but not today. I had the sky to myself.

[A2022]

half marathon results. I could not break into the top five. I still suck. maybe next year!

at this rate, I'm going to need to run until I'm 75 to get into the top five.....

but hey, my wife and I had a really fun time pretending we are athletes. she was 3:21 walking. Knoxville was good to us.

I only have one excuse; it was raining so hard my music shorted out at mile 8. I need "mah music"!










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made it to the finish line. it was a wet one. need to find a way to become faster. thinking about next year!

[A2022]

seatback bar storage tray.... 4 weeks of ultimate static load testing (20 lb). results from the 20 lb load test resulted in 1 small crack at one corner where the highest stress was predicted by analysis. the crack is small and did not propagate through. I am deeming this acceptable since the service load for this tray is 3.3 lb and the 20lb represents a +6g loading. the 3M dual lock velcro was secure at all locations. compared the load test tray (black) to a new tray (grey). installed the new grey tray. tray weight = 325 grams.









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analysis for ultimate 20 lb loading. this would be when the tray is loaded with 3.3 lb and pulling 6g.

[A2022]

headset mounted with 3M Dual Lock (hard Velcro) is still holding after a year. the first test survived exactly one year and used 4.5 yr old 3M Dual Lock that was sitting on a shelf in the hangar. this time I used 1 yr old Dual Lock and scuffed the backside of the mount. it is exposed to hot and cold of a non-conditioned hangar in Ohio and has some vibration from the air compressor. the weight the mount is supporting is 1.1 lb at the end of the arm. the test will continue.....

[A2022]

RV9 flap appendage closure. I like the RV9 flap because it is lightweight and simple with superb operability (actually, amazing, good). however, there is an appendage on the inboard side that leaves both a step and a gap. is it a real problem, no, but I want to clean it up. I don't like things fluttering in the breeze. I believe a small button shaped like a football will work and a 90-degree angle piece. I will install these plastic pieces without removing any other aircraft parts. the RV9 flap bracket fairings are original and approaching 5 yrs, if I remember correctly.

I'll probably get 3 kts from this.
















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I can surely obtain 100 psi shear strength from this flexible adhesive. I didn't bother to scuff the paint, but rather just cleaned it. the button bond surface area = .237 inch ^2. 100(.237) = 23 lb capability. the force required to support the appendage = approx 0.2 lb. 23/.2 = 115 safety factor. the button is only loaded when the flaps are up, so that is relatively short duration for my aircraft. not much time for the adhesive to creep. the button should have a good long life. the plan is to set the buttons firstly, then add the angle piece to cover the slot using the same adhesive in a couple locations, doesn't need much.









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the bonded buttons work well but still leave a .2 gap at the aft side of the appendage. I'm OK with a .2-inch gap along the aft edge. the alternative would be to make the button a cam shape but then you would need a fixture to mount it at the correct angle. the button I used is round on the contact surface. I have bonded the angle yet because I need to make the bond surface larger, but I installed it to have a look. seems OK.









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gluing the angles was easier than I thought it would be using some string and nuts for weight. syringe for applying glue precisely. let it cure for 24 hrs. hopefully, this will eliminate the NACA scoop like geometry created by the open appendage that may have been blasting air inside my flap, acting like a speed brake.

[A2022]

oil fill door hold-open idea, but not a very good one. however, I thought I would explore it anyway. 3/8-inch dia, tubing held it secure with winds from the North 12G16 and with a helicopter blast from 50 yds away. the blast was enough to rotate the nose wheel. tubing was still in place but the weak point is the insert into the cowling quick release hole. I thought I would try to make in internal tube stiffener to understand if it helps.

nice to have a helicopter noise maker and wind blower so close....

Tinlicker - You Take My Hand (Feat. Jamie Irrepressible) [Official Video]
https://youtu.be/-ZZl99ztxgA

[A2022]

oil fill door hold-open idea... continuing to explore this. added one hole at the top for a pin to engage. added a tube insert to stiffen it. still testing but it seems solid. installs in 5 seconds.

Naama · Sultan + Shepard · Nathan Nicholson
Something, Everything
https://youtu.be/oee_1wpJeaE

[A2022]

oil fill door hold-open idea... continuing to explore this. this is my latest configuration. I'll test it for a while. back to my book, Project Hail Mary by Andy Weir. goof off sci-fi stuff.




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I use a quarter turn to install and remove the tube in the socket, seems easy. pull test on just installed tube = 7 lb, at 24C. I'll check it again after a day or two. a leather punch makes a clean small hole.

[A2022]

oil fill door hold-open idea... continuing to explore this. the pull test after two days exceeded my expectations. I was actually expecting a reduction in tension capability, but it increased. the only way I can explain this is that the tube slowly creeps into the wall texture of the socket. I my case there is some paint primer in there. anyway, it appears to become stronger with time for my socket texture.

aft socket
just installed pull test = 7 lb
after two days pull test = 12 lb

fwd socket
just installed pull test = did not test
after two days pull test = 9 lb

so, where to store this tube? I could attach it inside the oil door somewhere, but heat may affect it over time, but that would be the best location. for now, I'll attach it in the cockpit. wrap tightly with velcro strap squeezed the tube enough to secure.

this uses the standard oil fill door 3W camlock butterfly lock, but smoothed and polished . this is just a small widget but may be of benefit to some, so I'll offer it on the website. another widget!

also, I made a stubby 3" tube, not sure what I will use this for but it's in the plane. maybe for rain or something?

I noticed how red brown my hand and arm are, reminded of my Choctaw Indian heritage by way of Oklahoma.
























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stubby tube, partial opening

[A2022]

traveling is going to make me fat... the center line food buffet.

I don't like bug mess but I'm sure they don't either.

the oil access door flex tube works! somewhere in Illinois. 20 kt ground winds.