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  #11  
Old 04-07-2017, 07:43 PM
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RVTrumpet RVTrumpet is offline
 
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I'm not quite sure what the allure is of letting the canopy open under the power of the gas struts and slam into the stops vs guiding the canopy up to its stop with your hand. Am I missing something? Seems to me that if the canopy has a tendency to slam into the open stops it would make sense to not let it do that.

Similarly to closing the canopy, if you let go of the canopy while it's closing it'll fall closed hard. Doesn't mean it's broken, just means that extra care needs to be taken to lower it gently.

I know it's hard for some people to reach the canopy rails with the shoulder harnesses tight, but it's really easy to loosen them. My two cents.
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  #12  
Old 04-08-2017, 11:07 AM
rvbuilder2002 rvbuilder2002 is offline
 
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Quote:
Originally Posted by RVTrumpet View Post
I'm not quite sure what the allure is of letting the canopy open under the power of the gas struts and slam into the stops vs guiding the canopy up to its stop with your hand. Am I missing something? Seems to me that if the canopy has a tendency to slam into the open stops it would make sense to not let it do that.

Similarly to closing the canopy, if you let go of the canopy while it's closing it'll fall closed hard. Doesn't mean it's broken, just means that extra care needs to be taken to lower it gently.

I know it's hard for some people to reach the canopy rails with the shoulder harnesses tight, but it's really easy to loosen them. My two cents.
I agree 100% with Justin.

I checked our prototype yesterday The first RV-12 to be equipped with the new style struts) and didn't see anything unusual about how hard the canopy opens.

I actually wonder if people aren't comparing what they see to older slightly worn struts
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  #13  
Old 04-08-2017, 01:45 PM
AZLeeJay AZLeeJay is offline
 
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Quote:
Originally Posted by rvbuilder2002 View Post
I agree 100% with Justin.

I checked our prototype yesterday The first RV-12 to be equipped with the new style struts) and didn't see anything unusual about how hard the canopy opens.

I actually wonder if people aren't comparing what they see to older slightly worn struts
I think you misunderstand my problem, it's not the difficulty in opening but the lack of dampening when opening and closing. Much different that the originals. Perhaps I just got a bad set? I've emailed support regarding this issue and am hoping to hear back soon.
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  #14  
Old 04-08-2017, 05:23 PM
WayneJ WayneJ is online now
 
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I agree with Lee, there seems to be some misunderstanding of our problem. I'll try again to explain what I think is going on.

I believe these struts are meant to function in 2 ways:
One, they provide assistance in opening and closing the canopy by offsetting the considerable weight of the canopy by way of high gas pressure (spring) inside the strut that forces it into the extended or fully open position.
Two, they have a damping action that slows or controls the rate of extension. This is necessary because of the very high spring force which if left uncontrolled, would allow the canopy to slam against the stops. The damping action, or lack of it, is where the problem lies.

My old struts provided much more of the damping action in the opening direction. It could be heard and felt from about the half open position to full open and effectively controlled the opening rate. (Not enough to just let go of it though). The new ones don't kick in until the canopy is almost fully open and then it's too little, too late to be of much help.

I don't think they are intended to provide any damping action in the closing direction. I have not sensed it on either set of struts. But the gas pressure assists closing by countering some of the weight.

This is not something I can't live with because I always hold on until it gently reaches the stops. BUT, if it was to slip accidentally out of my hand or a gust of wind caught it, or someone else opens it and lets go, the rate of speed by the time it reaches the stops could cause considerable damage. There is definitely a difference in how the 2nd set performs compared to the old ones. Maybe I got a bad set?
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  #15  
Old 04-08-2017, 06:15 PM
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Just another data point, but when I replaced the lift struts on my RV-10 with heavier duty struts, I had a similar problem where the doors would slam open too fast for my liking. I attributed this to the struts being designed for heavier loads that the weight of my doors.

I found that after a short time they seemed to weaken to the point that I no longer had to control the opening speed with my hand. In fact, they have now become almost neutrally balanced, and won't raise the doors all the way up without a little help.

I expect that at some point they may have to be replaced again but they are still working satisfactorily. I installed them in July of 15.

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  #16  
Old 04-08-2017, 07:18 PM
gasman gasman is offline
 
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Struts do have a built in cushion if installed with the small diameter rod down when the canopy is open.

If installed with the big diameter body down when the canopy is open, there will be no cushion just before full extension.
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  #17  
Old 04-09-2017, 09:39 AM
Larco Larco is online now
 
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The struts that I referred to in my previous post installed as per instructions on an RV12 are the new ones mounted with the large body up and they act like a HUGE SPRING without any dampening affect what so ever. The canopy will slam open VERY hard if not contained. IMHO someone is going to break something. Maybe this is a defective new batch that was made without any dampening ability? In 40 years as a mechanic I have never seen a strut behave this radical. I think the band wagon may fill up regarding this issue. :-)
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  #18  
Old 04-09-2017, 10:21 AM
rvbuilder2002 rvbuilder2002 is offline
 
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Quote:
Originally Posted by LARCO View Post
Maybe this is a defective new batch that was made without any dampening ability?
Possible

Has anyone actually contacted Vans tech support about it?
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  #19  
Old 04-09-2017, 12:51 PM
Larco Larco is online now
 
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Hi Scott, I think AZLeeJay has via Email. I have admit that I thought it was maybe an overreaction until I went over to see for myself. Holy Moly, you have see it to believe it. And please understand that I'm just trying to be helpful here by adding my 2 cents.
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  #20  
Old 04-18-2017, 04:29 PM
rvbuilder2002 rvbuilder2002 is offline
 
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I finally had some time to take a look at this.
I confirmed that the gas struts that are currently on the demonstrator are the same part # as what are supplied in the finish kit, and that they match the number that the manufacturer had originally specified as being the equiv. of the original part except with metal ends.

The struts on the demonstrator do not dampen like a soft close cabinet door, but they do not slam the canopy open either.
Out of numerous pilots flying the airplane, no one made any comments when the struts were changed.
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