Camper Trailer Gas struts

Hi Gazz
With our Ultimate camper , older one with a very heavy lid, the big strut has to be one that works in both directions ……… pushes up to open, lowers fairly gently once past the 90 degrees, then pulls up to close.
In other words it pushes up in both directions, and also applies the brake in lowering in both directions.
I’m wondering if you maybe need that type ….. they are pretty expensive.

Cheers
Jim

Just confirming you are undoing the cantilever rack from the base for opening and closing? Need to start simple with problem solving. I had an m3. Never had an issue.

Sounds spot on mate. Yes, that one point is the hard bit for sure. Hopefully the right struts will sort you out.

Be wary of using an electric winch. If some faux pas has been made, expensive damage could be done before anyone realises it's taking more force than normal.

Hi Gazz,
Let me add my bit. The gas struts act as 'constant force springs', in other words, they apply the same force across the entire stroke. This differs to coil springs which increase or decrease force with extension or contraction.
In your case, when the camper is closed, the main gas struts are applying force in the direction to open the camper. They are acting to balance the mass of the camper floor and canvas thereby assisting you to open up. If the gas struts are selected appropriately, you should not expect to see the floor start opening by itself when you release the locking clips!
When you start opening the camper and the floor starts rotating to the vertical position, the mass of the floor/canvas transfers more to the floor hinge and away from the gas struts, so the actual opening force you need to apply manually reduces and the gas struts (still applying constant force) start to take over the load.
As the floor rotates past vertical and reaches the point where the gas strut pivots align with the floor hinge pivot point, the gas struts are not doing anything in the way of opening the floor as all the force is applied to the hinge and the floor is basically in free fall. However, once the floor goes beyond the point where the pivot points are aligned, the gas struts are now going into compression, and therefore start to apply a retarding force to the floor, slowing it down.
Once the floor is on the ground, the opposite scenario is true - the gas struts are now attempting to close the floor!
If 2 x 500N struts do not provide sufficient force to assist you to close the floor, then higher rated struts are probably needed. I would look at the condition of the floor hinge point - are they corroded? Need lube? Ditto for the strut attachment points. Extra friction will detract from the gas struts performance.
1200N gas struts will not make it harder to open, but may make it harder to close. If you know who supplied the gas struts, it may be possible to have extra gas pressure applied (extra force) rather than buy new gas struts. McNaughtin's do this for free if the gas struts are purchased from them. The danger is that if you go too high, the gas strut attachments point may not have sufficient strength to handle the added load.

AFAIK from my 1997 Camp'o'matic 2000 the correct large strut is 700NM. The smaller struts are about 300 NM from memory also.

The 700Nm when in good shape should just raise the front a bit when the bolt is undone and also pop the rear up a bit when the rear bolt is undone when erected..
AFAIR the role of the struts is minimised as the tent reaches vertical due to the geometry of the mounts and the weight of the floor sticking out the back.
I used to grab the side wall then and pull the tent forward while stuffing the canvas and once the floor grid goes over vertical it will want to fall down and the struts slow it down to enable final stuffing.

I fitted a manual hand winch to use when single handedly closing when on a slope to help with stuffing as I could wind then go around stuffing and then wind a bit more.etc.

It is pointless considering gas strut pressure/force without also considering the mounting geometry (and stroke).
When I built the OKA pop top, I calculated the forces approximately, then ordered struts that were a tad longer than I anticipated and mounted them on adjustable points so that the opening and closing forces can be adjusted easily. I recently added some weight to the pop top. It easy easy to adjust the mounting positions to compensate by simply changing the mounting points.

The gas strut is visible at the front.
Cheer,
Peter
OKA196 motorome

You need to go back to the original Newtons & the original mounting, presumably that it is still at the original weight ??
If you need to up the pressure don't over do it ..
If you go to a good strut shop :Australia built : they can work it out for you but you will have to know the exact weight ...you can send them back to up the pressure but not reduced ..
If you change the mounting position then it will change the force on lifting and clothing
This was my experience.. good luck .