A

AFulmer

Active Member
Dwg 33 calls for 2 flap pushrods made from AT6-058X5/16. Only piece I have is 9" long whereas dwg calls for 2 pieces 4 7/8" long? Even Van's "list" of kit parts on his web site specs a 9" piece called: FLAP PUSH ROD 4/6/7/8
AT6-058X5/16X9. Can these be 4 1/2" rather than 4 7/8" as called out on dwg 33, or should I order another piece of FLAP PUSH ROD 4/6/7/8
AT6-058X5/16X9?

TIA,
 
Pushrod length

Hi Al,

Tape your flaps in the up position and the acuator bar in the up position and make length template from a coat hanger. Use the rod ends to gauge the length you'll have to cut the rod. If I remember there is plenty of wiggle room to make these.
 
Mine are 4 7/8"

I just checked mine and they are 4 7/8" plus I had 3" left over. Make sure you're using the right rod. This is very small diameter rod. Look at your flap end fitting that will thread into the rod - they won't fit in the undrilled rod. You have to drill the rod before the hole is larger enough for the 1/4-28 tap. I had another piece that I had labeled (mis-labeled?) AT6 -058 that was larger in diameter than the flap tube.
 
Vans offers a hex shaft alredy drilled and tapped that is much beefier and safer. Call them and ask, they will know what you are talking about. ;)

-Jeff
 
RV_7A said:
Vans offers a hex shaft alredy drilled and tapped that is much beefier and safer. Call them and ask, they will know what you are talking about. ;)

-Jeff
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I'm commenting on this because the myth that the round flap rod is inferior persist. The round rod is plenty strong for the RV-7/A. Scott McDanials, formerly from Van's, has commented on this numerous times.
 
I agree that the as designed system is plenty strong enough, as long as it’s fabricated right. I think that the concern started when a few misguided folks bent them to make them fit “better” thus greatly impacting the rigidity and strength.

But, if a guy wants to use the hex stock I don’t see what the big deal is. It’s likely overkill for the RV7 flaps, but it’s not like it’s going to hurt anything and it’s easier to make sure you get the jamb nuts snugged down because you can put a wrench on it
 
mfleming said:
I'm commenting on this because the myth that the round flap rod is inferior persist. The round rod is plenty strong for the RV-7/A. Scott McDanials, formerly from Van's, has commented on this numerous times.
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This didn‘t fail in flight but it did fail. I’m sure it’s adequate for the task but I feel a lot more comfortable flying with hex rods.
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Malndi said:
This didn‘t fail in flight but it did fail. I’m sure it’s adequate for the task but I feel a lot more comfortable flying with hex rods.
View attachment 64114
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Obvious contact marks on the tube. Your hex rod will fail, or something else, if you subject it to the same torture that the round rod appears to have suffered. Almost looks like it was done purposefully.

This is how misinformation keeps itself alive, coming back again, and again, on this very tired subject.
To my knowledge, none of either type have ever failed when properly fabricated and installed.

But, alas, the hex rod looks stronger, so it must be better…..
 
But, it can happen. Just make sure to run your tap down the center.
 

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JonJay said:
Obvious contact marks on the tube. Your hex rod will fail, or something else, if you subject it to the same torture that the round rod appears to have suffered. Almost looks like it was done purposefully.

This is how misinformation keeps itself alive, coming back again, and again, on this very tired subject.
To my knowledge, none of either type have ever failed when properly fabricated and installed.

But, alas, the hex rod looks stronger, so it must be better…..
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No, those marks occurred in the process of removing it after it failed.

When the now-broken bit is still tight on the rod end that’s how it looks after using pliers to get it off.
 
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Desert Rat said:
I agree that the as designed system is plenty strong enough, as long as it’s fabricated right. I think that the concern started when a few misguided folks bent them to make them fit “better” thus greatly impacting the rigidity and strength.

But, if a guy wants to use the hex stock I don’t see what the big deal is. It’s likely overkill for the RV7 flaps, but it’s not like it’s going to hurt anything and it’s easier to make sure you get the jamb nuts snugged down because you can put a wrench on it
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The best reason to to use this optional part.
 
I believe some miss the point. One is already done. The other has to be fabricated and tapped. I have seen some pretty poor tapping examples and that is even if the the buider gets the tap axis correct and uses the correct tap !!!!!!! I love the VA-256 on the RV-7 and RV-8 and shortened for the RV-6. I will side in this instance on aviation safety, ease of build, and less builder error. But hey, what do I know. This is the internet.
 
Dougnabbit said:
I believe some miss the point. One is already done. The other has to be fabricated and tapped. I have seen some pretty poor tapping examples and that is even if the the buider gets the tap axis correct and uses the correct tap !!!!!!! I love the VA-256 on the RV-7 and RV-8 and shortened for the RV-6. I will side in this instance on aviation safety, ease of build, and less builder error. But hey, what do I know. This is the internet.
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I agree. But taking this a step further, in the interest of safety, some people shouldn’t build their own airplane either. If you don’t have the skills to tap a hole correctly, or the inkling to learn, you know what side of the fence you should stay on.
Examples of this on other parts get posted here all the time and one has to just shake their head. This isn’t hard stuff to do right.

That said, I would certainly buy the ready made part to save time. It wasn’t available when many of us built our machines.

Still, in this post we have one that, evidently, mysteriously, failed, but not in flight, huh? and one that wasn’t tapped correctly that failed.
Anyway, we beat this one to death….
 
JonJay said:
If you don’t have the skills to tap a hole correctly, or the inkling to learn, you know what side of the fence you should stay on.
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It's one thing to tap a hole in a chunk of metal with plenty of material surrounding the hole. It's another to tap a thin tube with little margin for error in alignment, so maybe there's no reason to denigrate people who choose a more robust, less error-susceptible solution which adds practically no weight.

We're constantly debating things like people swapping rudders so that they can exceed Vne with what they think is more flutter margin...this seems to be a minor change with some pluses and no minuses.

And yes, I have the hex pushrods on mine. Cause it's my airplane and I can. :)
 
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