Adding Gas Struts for Roof Assist Question

[Flysar]

I have a no-name fiberglass 8' cab-over camper that uses 4 crude pistons and CO2 to raise a heavy fiberglass roof. In order to conserve CO2 I would like to add gas struts to my camper and I have an idea of how to go about it but just want to confirm my idea with those who have completed the mod. By adding the struts I'm assuming it would require less CO2 pressure and therefore my 10lb bottle will last longer.

1. Weigh the front of the roof, in the center, where I plan to install two gas struts using a 2x4 propped between the roof and a bathroom scale.
2. Weigh the back of the roof where I plan to install two gas struts as described above.
3. Divide front and back weights by 2 since I'm using 2 struts in each location.
4. Select struts with less force than the divided front & back weights so the top will close under it's own weight.

Example:
Front weight 140 lbs / 2 = 70 lbs use (2) 60lb struts
Rear weight 60 lbs / 2 = 30 lbs use (2) 20lb struts

I may be way off, if so please let me know.

Thank you

 

[bill harr]

Lots of gas strut information here.

 

[Flysar]

Lots of gas strut information here.

Thank you for the link.

I read/scanned all 31 pages and there is a lot of good info for FWC owners using what others had experienced but no calculations. I did find on page 31 where one person had a similar idea to mine, weighing the roof before buying, but there were no follow-ups to his post. I may join the forum and try to contact him.

I emailed and recvd a response from FWC, before starting my thread here, and asked how they determined what size struts to use and they did not offer any assistance other than to try the forums.

Thanks again and I'll continue my search.

 

[Dragos28]

have you considered 12v actuators?
they draw very little power so you could use a small battery.

 

[Flysar]

have you considered 12v actuators?
they draw very little power so you could use a small battery.

I had not but after a quick search that may be the best option; eliminates CO2 bottle, leaks, and refills while greatly improving lift maximums if I add racks and gear. Should be a relatively easy swap out too.

Down side would be a failed motor with no other way to lift the roof. Right now I have a portable air compressor as a backup for lifting the roof should my CO2 run out.

I'm definitely going to look into using them, excellent idea, thank you.

 

[Dragos28]

I had not but after a quick search that may be the best option; eliminates CO2 bottle, leaks, and refills while greatly improving lift maximums if I add racks and gear. Should be a relatively easy swap out too.

Down side would be a failed motor with no other way to lift the roof. Right now I have a portable air compressor as a backup for lifting the roof should my CO2 run out.

I'm definitely going to look into using them, excellent idea, thank you.

I figured that would be the best option.
Here's what i built
http://www.expeditionportal.com/forum/threads/149097-Leveling-Lifting-Roof-Top-Tent-rack-with-Actuators

 

[Flysar]

I figured that would be the best option.
Here's what i built
http://www.expeditionportal.com/forum/threads/149097-Leveling-Lifting-Roof-Top-Tent-rack-with-Actuators

Very Nice!

When the time comes I'll need to pick your brain about the controller.

 

[Dragos28]

Very Nice!

When the time comes I'll need to pick your brain about the controller.

here is the full build thread including detailed pictures of the controller

http://www.tundratalk.net/forums/tundra-4x4-off-road-tech/505993-rtt-rack.html

not sure, but i think you may need to register to see the photos.

 

[Flysar]

Rain finally stopped so I raised my top, 2 pistons were leaking so it took some extra CO2 and manual lifting (looking forward to no more of that), took measurements, and I have (4) 12v linear actuators en-route. Ordered from Tampa Motions Co, less than 45db motor noise, 12 mos warranty, and great price. Can't wait to get started on the retrofit!

 

[Dragos28]

nice, make sure to post pictures of your project!!

 

[Corneilius]

For anyone else reading, we were having trouble lifting a camper top with our pneumatic actuators running off the vehicles OBA. The actuators were pretty much maxed out payload wise which made things tricky. We knew the exact weight of the top from construction, so we simply "piggybacked" gas struts that we ordered online. We specified the lifting capacity of the struts @ %75 of total weight. This allows them to assist the pneumatic struts going up, and dampen the top coming down. Very happy with the result, and the gas struts were around $500 shipped. Drawback is the company said the life expectancy is 5-7 years, we're hoping for more owing to fewer cycles than most of their applications.