diamondaviators.net

It's possible that I may be able to help continue this effort and likely have access to the 3D design and printing tools needed. Let me know what you find out from Bret. Thanks!

Just talked to Bret. He says he has the resin and other supplies on order, and expects to have the first fin for the newer-style NLG faring ready to go in a couple of weeks. I'm the beta tester for that one, and if that all goes well, he said he will continue to make them for others that want them. I'll keep you posted here...

After flying 2 flights recently with left crosswind takeoffs, and subsequent corked nosewheel the whole flights, I am seriously ready for a solution. How difficult is the 3D process Mark? Assuming the cost of materials is small, especially compared to fiberglass, is it possible to just "eyeball" a virtual fin, print it, then make changes based on trial and error? I am happy to help in whatever way I could.

Steve, in the meantime as we wait for a fin... I’ve found that increasing nose wheel tension to 18 pounds (as documented by several of us here) largely solves the corking problem.
Wayne

So far Ive been using the procedure to tension to 18lbs which works, but it loosens up over time.

An alternative theory to fix the corked nose wheel issue is to tape two straws vertically to either side of the rear of the nose wheel fairing. This way when the nose wheel moves out to one side and encounters the rush of air not shielded why the NLG strut, it will be pushed back into place, rather than sucked into the moving air.

The theory is that the NLG strut blocks the air over the nose wheel fairing, leaving two high velocity streams on either side of the nose wheel. Each of these streams want to suck the nose wheel in, corking it to one side or the other.

Id be willing to try this myself but Im fearful of any side effects or imbalance or flutter. But Im fairly certain the rudder on the DA-42 has a similar setup, with a trim tab that looks like a T, keeping the rudder pointed straight back.

With all this said, Id love a fin for the newer style wheel fairings once Rick and Bret have completed flight testing.

Had another corked flight after a left crosswind takeoff... and I'm desperate to find a solution. Looking at the picture of the fin, it looks really easy to design and 3D print, but without some type of scanner, the bottom curvature would be trial and error. Using freebie tinkercad site, I created a 2 minute rough start that looks close. Tinkercad estimates commercial printing cost at $80. I cannot upload .stl files here, but PM me if you want the file to look at and play with, or try if you have a printer.

Unfortunately, I don't have anything new to report. Still no word from Bret - I'll ping him again after the holidays and see if I can at least get the model and any other information he has.

Rich wrote: ↑Thu Jun 13, 2019 5:14 pm Got to get a check of rudder trim and a stable airspeed assessment today. Not a bump in the air to be found, as I was flying early. Rudder trim set neutral (as recommended) plane flies with the ball centered and feet on the floor with the following conditions:
Wt: ~ 2040 lb.
CG: 96 in.
RPM: 2450
MAP (full throttle): 23.2
DA: 8000 ft.
TAS: 147 Kn.
POH number for this DA: 134 Kn.

Plus that annoying tendency for the A/P to fly with the left wing low is gone.

Now the tough stuff. Annual next month. Talked to my mechanic. He'd prefer it not be there when he does the annual, but otherwise he "knows nothing". So there's that.

Fin1.jpg
Fin2.jpg

Rich, I was thing about trying to create a fin for my 2010 XLS (newer wheel pant shape) using a 3D printer. Next time you're out at your plane, can you measure and send me the thickness of the fin and the width and length of the base plate that attaches to the wheel pant?

Thanks!

Should have measurements by tomorrow night.

MarkA wrote: ↑Fri Dec 27, 2019 3:35 am

Rich wrote: ↑Thu Jun 13, 2019 5:14 pm Got to get a check of rudder trim and a stable airspeed assessment today. Not a bump in the air to be found, as I was flying early. Rudder trim set neutral (as recommended) plane flies with the ball centered and feet on the floor with the following conditions:
Wt: ~ 2040 lb.
CG: 96 in.
RPM: 2450
MAP (full throttle): 23.2
DA: 8000 ft.
TAS: 147 Kn.
POH number for this DA: 134 Kn.

Plus that annoying tendency for the A/P to fly with the left wing low is gone.

Now the tough stuff. Annual next month. Talked to my mechanic. He'd prefer it not be there when he does the annual, but otherwise he "knows nothing". So there's that.

Fin1.jpg
Fin2.jpg

Rich, I was thing about trying to create a fin for my 2010 XLS (newer wheel pant shape) using a 3D printer. Next time you're out at your plane, can you measure and send me the thickness of the fin and the width and length of the base plate that attaches to the wheel pant?

Thanks!

Fin thickness: ~ 7.5 mm
Base plate width/thickness: 25/7 mm
Length of base plate: 33 cm (330 mm)

Note that the trailing edge of the base plate lines up with the trailing edge of the fairing. There's a possibility you'll need to tweak the base plate length due to differences between my old fat-gear fairing and yours. If it's not clear from the pictures I posted, the fin is flush with the right edge of the base plate which aligns it pretty well with the fairing seam. The fastening screws are offset on the left side, lining up with the mounting holes for the fairing itself. I'm guessing getting some poster-board, using trial-and-error to figure out the contour of the fairing is in your future