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Stronger gas springs for RV-7 canopy

N737Z

Member
I have had my canopy blow down with a wind gust and it broke a corner off. Repair was easy enough, but I decided to replace my stock gas springs, which are very weak, with stronger springs. What a difference it makes! I went from 100n to the 150n and my canopy is much more secure in the raise position.

Gas Springs available from the following link:

http://www.pointswestmarketing.com/liftomat.htm

Regards,

Don in PHX:D
 
Part number

Don,
Sounds like a good idea.
Thanks for the information.
Can you tell us what Part # is the RV replacement?
and what was the cost?
Thanks,
 
hi,
we're working on a related issue as well...
in my opinion it's not just the weak springs... the problem is, once they get into the compressed position which is about 15" before closing, they have no upward force any more and the canopy slams down.
what we try to come up is a nice solution that guides the canopy for the last few inches as well as dampens/slows the movement, probably with 2 more small lift struts or so, not yet engineered and decided upon.

anybody with a succesful setup?

regards,
bernie
 
I've found the gas springs used by Van's need to be replaced every couple of years to maintain what I believe is adequate force. On the other hand, putting in stronger springs may create another problem for you in that the compressed spring tends to force the closed canopy forward against the cowl deck. You may be trading one issue for another. I'd recommend just getting new springs every couple of years, if necessary.
Terry
 
I've found the gas springs used by Van's need to be replaced every couple of years to maintain what I believe is adequate force. On the other hand, putting in stronger springs may create another problem for you in that the compressed spring tends to force the closed canopy forward against the cowl deck. You may be trading one issue for another. I'd recommend just getting new springs every couple of years, if necessary.
Terry

Terry knows of what he speaks.
 
The new set of gas springs are the exact dimensions of the stock springs and actually have a better damping action to slow the extension. The structure per Van's plans is more than strong enough for the slightly greater force of the stronger springs. I don't have the part number handy, but write down the number off your stock springs and go to the sizing chart on the web site to get the identical size unit with the next step up in force.

Regards,
Don;)

http://www.pointswestmarketing.com/liftomat.htm
 
The new set of gas springs are the exact dimensions of the stock springs and actually have a better damping action to slow the extension. The structure per Van's plans is more than strong enough for the slightly greater force of the stronger springs. I don't have the part number handy, but write down the number off your stock springs and go to the sizing chart on the web site to get the identical size unit with the next step up in force.

Regards,
Don;)

http://www.pointswestmarketing.com/liftomat.htm

The springs push fwd on the canopy frame when the canopy is closed (by design). I have seen the canopy position change by as much as 1/8" fwd after installing the gas springs (all canopy fitting done without the gas springs installed).
Adding an even higher newton value spring could make this even worse.
 
attach springs to canopy hinges

This question will reveal how much time I have spent looking at my canopy plans, but why can't we just attach the gas shocks to the canopy hinges and have them push up from below? This is how the canopy works on the Lancair Legacy.
 
Last edited:
from below

This question will reveal how much time I have spent looking at my canopy plans, but why can't we just attach the gas shocks to the canopy hinges and have them push up from below? This is how the canopy works on the Lancair Legacy.

I have seen this on another RV-6 tip up. I wondered about why it was different, until now!
Good thread.
 
Excellent input. I have not had any movement, but I will certainly monitor, evaluate, and report back with any adverse affects. thanks Gang.
don
 
Lift-o-mat vs Block-o-lift

It is time to change out my canopy lift struts. Looking on the points west web site on this thread there are some lift struts that look the same, but they have a valve for locking the strut in any position. I thought this might come in handy in higher wind conditions. Does anybody know anything about the Block-o-lift struts? Do they otherwise work the same? Any downside to using this type of locking strut?
 
Thank you folks for the input on the gas spring canopy struts. I went to Orr & Orr and purchased the 35# version. An EXACT replica with a higher tension rating was just what was needed for my tip up RV7.
Orr & Orr charged me even less than what they showed (2) when in the cart ($12.50 ea) and I received 4 days after ordering.
Although I did not build my RV7, I have found VAF to be extremely helpful as an owner and make a daily morning habit to learn more about RV's, regardless of posts. Thank you all for your input.
 
On my RV-7.

I just replaced my lift struts with 40 pounders. Is this too much?

The ones I replaced were rated a bit more than 20 pounds.

Although I really appreciate not having the canopy slam down in a mild breeze now, I don't want to risk airframe damage.

Thanks.
 
I found a quick way to make a safety support by cutting a short piece of 1/2"sched 40 PVC pipe to fit over the gas strut support rod when extended. Slot the PVC about 3/8" end to end to allow the pipe to slide over the support rod, trim the inside end of the pipe in a bowl shape to fit the ball ends of the support rod. Works good for changing out the gas struts so the canopy stays up on it's own.
 
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