Jury strut Spar Mount Problem

[ksatter26]

Looks like I've once again been bitten by the parts redesign problem.

Early on I crimped the ends of my 4 sets of 0.5" dia 6061T6 jury strut tubes. (I documented the tooling I used in an early post.) I did this so that I could get the strut tubes off to the powder coater. I checked the build manual noting how the various pieces go together ...

Now I find that the Jury strut Spar mount brackets are of a new design with the tab 90 degrees off those in the manual.

I just sent an email to Chris with possible solutions:

(1) Swap my re-designed mounts for his previous design (if he has them ... tho I like the re-design better)

(2) Fabricate 3 new sets of jury strut tubes with the properly located crimped ends ... I have a 3' length of 0.5" dia 6061T6 on-hand and can possibly canabalize some of the longer "bad" tubes into shorter ones. (Also, if needs be, I have a source of the tubing 50 miles away in Ft. Worth)

(3) Fabricate 4 right angle adapters from small pieces of 0.75" 6061T6 L-angle which would bolt to the mounts and provide a tab to which I can bolt the jury strut tube.

Thoughts?

I've managed to install the 8 1032 rivnuts into the cowl mounting tabs. This was another adventure because my cheapie Harbor Freight Rivnut Installation Tool did NOT come with a 1032 mandrel (only 1024 and they don't have a source for a 1032 ... bummer). I went back to trusty YouTube and made up a serviceable tool from a 1032 bolt , nut, and 2 wood-bearing washers (the 0.75" dia kind). Worked pretty well but much more time consuming than with a real tool.

Still awaiting my replacement-replacement lift strut inserts .... been almost 9 weeks

[Badland-F5 Pilot]

I'm certainly learning from your build Kurt. Don't try to get ahead of the game as things seem to change making the getting ahead not beneficial. Sorry to hear of the issues with the struts.

Option 1 seems like the easiest, as you mention, if Chris can provide them.

Option 2 doesn't sound bad at all, but would be time-consuming. However, it would get you the new design. There's a big benefit in that. The worst thing in the world is going with something that works because it's easier, but always seeing the work that was done, knowing it's not really what you wanted.

Option 3 Sounds do-able too, except is that going to take a long time and will you like the results?

At least you've got progress on the cowling, even if the HF tool wasn't the right size. At least you made some progress.

Todd

[ksatter26]

9 weeks waiting on replacement lift struts. I took measurements of the required lengths of the lift strut legs and I found that I have a sufficient excess of lengths that I could cut the ends off and drill out the rivets. I then used my cutoff tool to split the outer tubing lengthwise along the lift strut to free the insert. I then polished the barrels of the inserts. They now seem serviceable. If my replacements don't show up by mid-April, I just may use the refurbished inserts. I will mark the locations of the drilled-out rivets on the insert barrels and make sure that I position the new rivets such that I maximize the distance from the previous rivets locations. I will also epoxy the inserts in into the strut legs M

Hopefully the new design ( which seems longer) will arrive and I won't have to use the refurbished inserts.

Still shying away from removing any fiberglass from the cowl. I've tried positioning the cowl several times and it appears that some serious reshaping of the nose area will have to be done.

[LA F2 Flyer]

For the jury struts, I am inclined to say find a way to make them work with the brackets provided with the kit. Those brackets are very slick, and it keeps the jury struts more aerodynamic at the fittings, rather than the flats facing into the airflow.

If you cannibalize enough of the struts to shorter lengths and then only need to create one new one, I imagine that would work. But you'll likely need another trip to the powder coaters, correct?

If it were me, I would try to fabricate a bracket for the lowers to change the angle 90 degrees. I wouldn't mind someone more experienced than myself piping in here (Chris?), but it seems to me that, while the jury struts are structural, they are not AS structural as the struts themselves.

From my (limited) understanding, they don't support weight so much as act to prevent flex and vibration. So there should be some creative latitude.

Just my 2 cents...and likely worth EXACTLY that!

On a side note, I didn't crimp the jury struts until I had the wings mounted and then measured a few times, since every build will end up with variances built in...you would need to hang and align the wings before you truly can know how long they will need to be.