Stabilator attachment help needed

[LettersFromFlyoverCountry]

I am in desperate need of some advice on attaching the stabilator. After much wrestling I've been able to get everything to line up and I have gotten bolts in both of the bearings and I have even been able to engage the threads on the left side. But try as I might. I simply cannot get the bolt to engage with the nutplate on the right side. I've tried everything. Yesterday I took it off and I ran bolts through all lubed up and then today reattached and I'm having the same problem. I can get the bolt on the left side to engage but I cannot get the right side to engage and an additional problem is the design of this. There is almost no room to work.

Has anyone encountered this situation before and if so, do you have any advice at all?

 

[Tony_T]

I am in desperate need of some advice on attaching the stabilator. After much wrestling I've been able to get everything to line up and I have gotten bolts in both of the bearings and I haven't even been able to engage the threads on the left side. But try as I might. I simply cannot get the bolt to engage with the nutplate on the right side. I've tried everything. Yesterday I took it off and I ran bolts through all lubed up and then today reattached and I'm having the same problem. I can get the bolt on the left side to engage but I cannot get the right side to engage and an additional problem is cuz of the design of this. There is almost no room to work.

Has anyone encountered this situation before and if so, do you have any advice at all?

Have not had that problem exactly, but unless there is a structural interference, it likely is a slight misalignment. Have you tried inserting a bullet to wiggle the holes into alignment? Since it is a nut plate you would not want to drive the bullet in enough to damage the nut plate.

Here is a post that has bullet pics:

https://vansairforce.net/threads/engine-mount-“bullet”.200453/post-1564545

It is also very helpful if you have some kind of support under the stab to hold it steady.

 

[Brett H]

I am in desperate need of some advice on attaching the stabilator. After much wrestling I've been able to get everything to line up and I have gotten bolts in both of the bearings and I have even been able to engage the threads on the left side. But try as I might. I simply cannot get the bolt to engage with the nutplate on the right side. I've tried everything. Yesterday I took it off and I ran bolts through all lubed up and then today reattached and I'm having the same problem. I can get the bolt on the left side to engage but I cannot get the right side to engage and an additional problem is the design of this. There is almost no room to work.

Has anyone encountered this situation before and if so, do you have any advice at all?

I’m assuming when you were building the stabilator that at some point you attached the bulkhead from the tailcone that has the two stabilator attachment points. So, you know that it attaches.

I’m assuming that the difficulty is getting the stabilator attached to the fuselage sitting on the landing gear.

If so, what I did was shim up the stabilator to match where it attach the tailcone. The challenging part comes when you start to insert the bolts. As bolts start to engage the tailcone sees the weight of stabilator the tailcone and moves downward.

Is this the issue that are having?

Brett H

 

[daveyator]

First time I thought I had worked out an ingenious one man method using a hydraulic lift. Total fail. I wound up with one bolt in and one bolt stuck half in, running out of daylight in a hangar without power. Found new uses for the English language that day.
My advice is to get your helper (2 helpers if possible) to juggle it into the bearings and as close as possible. Then carefully move it until the top travel stops engage, the nice curve of the stop captures the bolt and everything just seems to position itself. Gives you a positive position to work from. Hope you can follow my description. Trailing edge should be up and the bolt sits nicely into the curve. Still may need a bit of fiddling, but you will be pretty close. Good luck
cheers, DaveH
120485

 

[bobg56]

I am in desperate need of some advice on attaching the stabilator. After much wrestling I've been able to get everything to line up and I have gotten bolts in both of the bearings and I have even been able to engage the threads on the left side. But try as I might. I simply cannot get the bolt to engage with the nutplate on the right side. I've tried everything. Yesterday I took it off and I ran bolts through all lubed up and then today reattached and I'm having the same problem. I can get the bolt on the left side to engage but I cannot get the right side to engage and an additional problem is the design of this. There is almost no room to work.

Has anyone encountered this situation before and if so, do you have any advice at all?

Remove the stab, set it on saw horses, take a .38 cal. pistol bore brush on a drill and clean up the hinge flange holes then remount the stab and try doing the right bolt first, make sure to add a little grease to bolts.

 

[LettersFromFlyoverCountry]

Remove the stab, set it on saw horses, take a .38 cal. pistol bore brush on a drill and clean up the hinge flange holes then remount the stab and try doing the right bolt first, make sure to add a little grease to bolts.

I'm not sure what that tool is but I'm sure I don't have it. I did run bolts through and into the nutplate when the stabilator was off the plane.

 

[LettersFromFlyoverCountry]

I’m assuming when you were building the stabilator that at some point you attached the bulkhead from the tailcone that has the two stabilator attachment points. So, you know that it attaches.

I’m assuming that the difficulty is getting the stabilator attached to the fuselage sitting on the landing gear.

If so, what I did was shim up the stabilator to match where it attach the tailcone. The challenging part comes when you start to insert the bolts. As bolts start to engage the tailcone sees the weight of stabilator the tailcone and moves downward.

Is this the issue that are having?

Brett H

Sort of but not actually. The problem is I can't get the bolt threads to engage the nutplate.

 

[docjjrmd]

Run a die down your bolt. Fine thread bolts get the first 2 or 3 threads roughed up frequently and then won't catch the nut plate threads easily particularly if there is small alignment issue. Put the problem bolt in first. Do not run a tap in the nutplate as that well cut out the material that makes it "lock" .

 

[CTCole]

Running a bolt into the nutplate, with the stabilator out of the way, was a good idea. It's still possible the nutplate threads are bunged up, and you might try threading a tap into the nutplate -- being very gentle as you begin threading it in. Have you tried putting the right bolt in first, and then the left-- just in case there's some bad juju in the alignment? My only other last-ditch suggestion is to make sure you use a brand new bolt, and closely examine the threads at the tip -- I've run into a few cases where threads bunged so little I have to squint to see the flaws made all the difference. Here's hoping.

BTW, I've found your EAA builder blog a great help. Thanks!

--Chris

 

[LettersFromFlyoverCountry]

I tried that (bad bolt first) yesterday to know avail. A bunch of RVators are coming over tomorrow to assist. I think one person doing this is bound for failure or at least distress.

Btw I try never to run taps into a nut plate

 

[subpar_bucker]

Do you have wobble extensions for your sockets? My tech counselor introduced these to me as part of my build. I had never used them before. It seems like they allow the bolt to line up square with the hole more easily. I definitely used them inserting these bolts on my build.

Wobble Socket Extension Set, 9-Piece

Amazing deals on this 9Pc Wobble Socket Extension Set at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

 

[bobg56]

I tried that (bad bolt first) yesterday to know avail. A bunch of RVators are coming over tomorrow to assist. I think one person doing this is bound for failure or at least distress.

Btw I try never to run taps into a nut plate

You may want to check for any interference , contacting areas not allowing the stab to line up with hinge bearings

 

[docjjrmd]

I tried that (bad bolt first) yesterday to know avail. A bunch of RVators are coming over tomorrow to assist. I think one person doing this is bound for failure or at least distress.

Btw I try never to run taps into a nut plate

The tolerances are very tight (stating the obvious here!) A couple more things to try. One, loosen the hinge stop bolts slightly until stabilator installed then re-torque. There may be a little spring / angle in the hinge bracket assy. Two, run a #12 reamer through the bolt hole and shims up to the nutplate on both sides. See 9iS/U-04 for diagram.

 

[lr172]

I am in desperate need of some advice on attaching the stabilator. After much wrestling I've been able to get everything to line up and I have gotten bolts in both of the bearings and I have even been able to engage the threads on the left side. But try as I might. I simply cannot get the bolt to engage with the nutplate on the right side. I've tried everything. Yesterday I took it off and I ran bolts through all lubed up and then today reattached and I'm having the same problem. I can get the bolt on the left side to engage but I cannot get the right side to engage and an additional problem is the design of this. There is almost no room to work.

Has anyone encountered this situation before and if so, do you have any advice at all?

I can see the bolt angled upward. Loosen the other two all the way back to 1 or 2 threads of engagement. This creates some movement of the two pieces to help align the holes that are obviously not in perfect alignment. DO NOT try to start running in the middle one until you force it down enough to be square. Use a wrench on the head and use your other fingers to press or manipulate the bolt to be square. NEVER try to force a non squared bolt into a thread, escpecially one as thin and weak as a nut plate, lest you strip something.

Larry

 

[azonslow]

I am in desperate need of some advice on attaching the stabilator. After much wrestling I've been able to get everything to line up and I have gotten bolts in both of the bearings and I have even been able to engage the threads on the left side. But try as I might. I simply cannot get the bolt to engage with the nutplate on the right side. I've tried everything. Yesterday I took it off and I ran bolts through all lubed up and then today reattached and I'm having the same problem. I can get the bolt on the left side to engage but I cannot get the right side to engage and an additional problem is the design of this. There is almost no room to work.

Has anyone encountered this situation before and if so, do you have any advice at all?

Check your conversations.

 

[LettersFromFlyoverCountry]

Problem solved today thanks to fellow RVators.