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Re: Hatch Gas Spring/Strut Calculator

PostPosted: Tue Oct 03, 2017 12:38 am
by danlott
pmeyers wrote:The dimensions that I am working with are very similar to those of the hatch calculator. 48" hatch, 28 " strut and 12" stroke length. If the attachment point inside the galley is determined by the strut length as a radius from the hinge point then it would seem to be that when attached to the hatch it would not be long enough to even open the hatch. This would be made worse by the fact that the attachment point on the hatch is calculated on 85% of the stroke. My trailer is a Benroy shape and the hatch curves down at the hinge.

Take a look at the picture that is in the first post.


One end of the strut attaches to the side wall of the galley wall at a point from the hatch hinge point that is equal to the overall length of the of the strut. The other end of the strut attaches to the hatch at a point equal to 85% of the strut stroke length.

In your case the strut should be attached to the galley wall 28" from the hinge point of the hatch. The other end of the strut should be attached to the hatch 10.2" from the hinge point. The measurements should be taken in a straight line from the hinge point and not follow the curve of the hatch.

When the hatch is closed the strut will be compressed to length of approximately 17.8 inches. This compression force is what allows the hatch to open and stay open.

The overall clearance height that you will have with your hatch open depends mostly on your hatch design and the height of the hinge point from the ground level. If you desire more or less overall clearance height then you will need to adjust the recommended strut attachment points.

If you use the dimensions provided in the calculator spreadsheet the overall clearance height should be sufficient for most normal height people.

Dan Lott