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This just may be a deal killer....

snoopyflys

Well Known Member
I installed my wings for the first time and everything seemed to line up ok. The wing main and rear spars went into F-704 Center Section and F-705B Center Section bars. Homemade drift pins fit with a little trimming of the F-704C and D plates. So far so good. Well so I thought. I added a couple to bolts with threads to each side to ensure the wings were securely attached. One of the bolts did not go in easily. Used a wrench to get it into place, noticing it was a little resistant to go in. But it went in. Did not think anything about it, until I removed the wings to adjust the sweep by trimming the rear spar tabs. After removing all of the bolts and drift pins and removing the wings, I found THREADS IN THE LOWER INBOARD HOLE F-704F CENTER SECTION 3/4 BAR WHERE THREADS DON'T BELONG! :eek: :mad: Checked the remaining holes that I had inserted bolts/drift pins, none showed signs of threading or galling :eek: .

Here's a pic of the threaded hole viewed from the right side, inboard using a mirror facing forward;

IMG_1072_zps6dd0a297.jpg


I will be contacting Van's about what I can do to fix the threaded hole. This is by far the dumbest move I have done. But, in the mean time, I would appreciate comments/suggestions on what can be done to fix this threaded hole short of starting over.
 
I installed my wings for the first time and everything seemed to line up ok. The wing main and rear spars went into F-704 Center Section and F-705B Center Section bars. Homemade drift pins fit with a little trimming of the F-704C and D plates. So far so good. Well so I thought. I added a couple to bolts with threads to each side to ensure the wings were securely attached. One of the bolts did not go in easily. Used a wrench to get it into place, noticing it was a little resistant to go in. But it went in. Did not think anything about it, until I removed the wings to adjust the sweep by trimming the rear spar tabs. After removing all of the bolts and drift pins and removing the wings, I found THREADS IN THE LOWER INBOARD HOLE F-704F CENTER SECTION 3/4 BAR WHERE THREADS DON'T BELONG! :eek: :mad: Checked the remaining holes that I had inserted bolts/drift pins, none showed signs of threading or galling :eek: .

I will be contacting Van's about what I can do to fix the threaded hole. This is by far the dumbest move I have done. But, in the mean time, I would appreciate comments/suggestions on what can be done to fix this threaded hole short of starting over.

I don't think this is a disaster, but you do need to call Van's.

My guess? You'll need to upsize the hole to the first size that gives you a clean hole. And you'll need a bolt to match. They do make oversize AN bolts.

See this thread for more info:

http://www.vansairforce.com/community/showthread.php?t=906
 
Wow! Are the threads cut all the way around in the hole? Were the threads a larger diameter than the bolt shank diameter? A call to Vans and ask if a reamer to clean it up is acceptable.
 
Check your bolt's!

Check the straightnes the of the bolt's!

You will be surprised how bowed they are.

I checked the straightness of the bolts on a thick steel plate (rolled the bolts over the plate).

2 out of 8, I trowed away and bought new once.

Check the thread diameter with a caliper, you will find differences. As long as the thread diameter is equal or smaler than the rest of the bolt, it is ok.

Also reduce the load on the wing, check the positioningduring the moment when you insert the bolts. Use alignment pins, so the hole will line up.

Put in bolts and dummy spar when you drill/rivet the center section into the fuselage.

Hope this helps!
 
Check the straightnes the of the bolt's!

You will be surprised how bowed they are.

I checked the straightness of the bolts on a thick steel plate (rolled the bolts over the plate).

2 out of 8, I trowed away and bought new once.

Check the thread diameter with a caliper, you will find differences. As long as the thread diameter is equal or smaler than the rest of the bolt, it is ok.

Also reduce the load on the wing, check the positioningduring the moment when you insert the bolts. Use alignment pins, so the hole will line up.

Put in bolts and dummy spar when you drill/rivet the center section into the fuselage.

Hope this helps!

+1 Yeah, non-aviaiton bolts are not straight or round and the holes are not either, until the final torque is applied to the proper bolts. I set some bolts on vee blocks and checked straightness with a dial indicator.
 
I'm anxiously awaiting to hear what Van's says about this - I am sure there will be an approval or fix.

For future readers, if using hardware store bolts for this task, I would grind the threaded portion of the bolt to a bullet point, making sure there are no threads left. I have a drawer full of these "homemade bullet pins" from two airplanes.
 
The main spar bolts are an interference fit, this will likely mean reaming the holes out for an oversize bolt. Line reaming those in the aircraft isn't going to be fun, but it should be possible. This is assuming the correct OS bolt is available and that you can clean up the hole without exceeding design limits.
 
Vans's Says it's fixable...

Hey, thanks for the responses. This rates equal or worse that the wing falling of the workbench. This latest learning experience can be fixed according to Sterling and Van's engineering. Here's the response I received;

"I have showed your picture to the engineering team and they will allow an oversize bolt in your situation. They also said it is very important that you debur the end of these holes, if this scratch goes out the the edge of the bar you will need to buff it out.

For the oversize bolt you can contact Tammy at Phlogistion, they can also tell you what size ream you will need.

Sterling

PHLOGISTON PRODUCTS, INC.

TAMMY
503-985-3212"


So, I still need to contact Phlogistion on the oversized bolt and reamer. The real challenge is this hole in on the bottom and getting a reamer in there, perpendicular and square is daunting. I will try to keep this thread posted on my progress.
 
*UPDATE* There's a kit for that...

PHLOGISTON PRODUCTS, INC. has a "repair" kit available for situations as this :). As long a Van's says it is ok, these folks can provide you with the oversize NAS bolt and tools (reamer and bushings) necessary to do the repair job. Based on the information I got from their website and in talking the Tammy at PHLOGISTON PRODUCTS, INC., they fabricate wing spars for Vans. So, waiting on the kit to arrive and then get some instruction/guidance on performing the repair. I will update this post on my progress.
 
PHLOGISTON PRODUCTS, INC. has a "repair" kit available for situations as this :). As long a Van's says it is ok, these folks can provide you with the oversize NAS bolt and tools (reamer and bushings) necessary to do the repair job. Based on the information I got from their website and in talking the Tammy at PHLOGISTON PRODUCTS, INC., they fabricate wing spars for Vans. So, waiting on the kit to arrive and then get some instruction/guidance on performing the repair. I will update this post on my progress.

With this mod, will you be able to retain the 6 -3 G ratting?
 
Per the Mothership...

Van's Technical Support said via email yesterday, "No change to aerobatic limits." :D
 
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Great news, the acro is a big plus in my mind, There are so many little details that can cause a problem if your not really careful.
Jack
 
It's Fixed!

This too far too long to finish (gotta work to pay for this habit) but it's fixed. As I mentioned in my prior posts, I used a reaming repair kit supplied by PHLOGISTON PRODUCTS, INC. to affect the repair (free of charge :D) excluding the cost of the oversize bolt and shipping (PHLOGISTON PRODUCTS, INC. split the shipping which was kinda cool and answered all of my questions and concerns). The kit includes the reamer and jig with fittings that ensure the hole and reamer are in the proper alignment. The actual task is fairly simple and all of the threads were removed as I hoped. The new oversize bolt fits really well an only needs a couple of taps of a plastic hammer to install. Not as tight as the original but there is no noticeable movement of the bolt in the hole.

If anyone has this or a similar issue with installing their close tolerance bolts, give Van's a call. These kits are wonderfully designed and there is some wiggle room but for critical attachments like this, a call to Van's Tech Support is warranted. (I will be thinking about this bolt on the first flight). I will try to post some pics later on.

Thanks for the PMs from fellow builders who offered suggestions and words of encouragement. It really helps keep you going forward when something like this happens.

Regards,
 
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