Center of Gravity

msiminoff wrote:

diver110 wrote:
... I noticed that some hardsides have the same or similar center of gravities as pop-ups. Not all manufacturers list this, but some Lances have the same COG as a Hallmark I am looking at (36 inches), and others Lances are only slightly higher (38 inches). Am I correct that COG is THE issue with regard to tipping over.

With truck campers, the distance number (36" in your example) specified is best described as the center of balance and not the center of gravity....
I am not at all surprised to hear that both pop-up and hard-side truck campers to have a similar center of balance.
On the other hand I would expect that hard sided TC's to have a higher center of mass (CoG) and as a result are more prone to "tip over"... in comparison to a pop-up with the same center of balance location. I have never seen a TC manufacturer correctly specify the CoG.

All that said, with my TC I have made an effort to move my center of balance forward and to move the CoG lower. I've been in some crazy places with my rig (including the Land Rover driving course at Overland Expo) and have never once felt that I was at risk of a tip over. As with most things in life, you should always use common sense when driving a truck with a camper in the bed.

certainly would be important to know whether they are measuring from the front or the back. Odd that they would not make that standard.

The center of balance is typically measured forward from the back of the TC (where the end of the truck bed would be).

Hope this helps.
Cheers,
-Mark

That does help. I was trying to think through the physics of this. As you say, the center of mass is key. It seems to me there is not that much weight up high on a hardside. That is probably not that significant when comparing a hardside to a popup. But hardsides are bigger overall with more stuff in them, likely moving the center of mass higher. It seems to me possible on a hardside to move the center of mass down if intelligently designed and loaded. Also, the truck itself is relevant. I would guess a 1-ton helps bring the mass down compared to a half ton.