Hatch Pistons

[Kaz]

So I propped my hatch open on a support on top of a scale and came to about 75 lbs. So I installed two 50# struts, didn't work. I don't know if I have the geometry off or what.It closes nice and gentle but when opening I get to about half open I have to lift pretty hard and then it goes easy but then at full extension it wont hold the hatch open. Help!

[noseoil]

You need to weigh the hatch at the location where the supports attach. This means the angle they sit at and the force measured at that angle & location or "setback" from the hinge. If you measured it on the floor & straight down from the center, it isn't an approximation of the actual forces being generated at the support locations. Make sense?

[Woodbutcher]

I used this place for my struts. They have a strut that allows you to bleed off pressure till you reach just the right fit. But caution. It is a one way thing. Bleed off to much and there is no fixing it. So if you use them do just a little and check and repeat till they work.

http://www.spdhardware.com/catalog/GSVL ... s%20Spring

[coyote]

viewtopic.php?f=21&t=6319&hilit=Gas+struts+Grant#p70679 Read, saved this one, " Hatch Strtus...Formula?" ( of course my new ones are still on the bench and I made a better broom stick...) coyote

[tony.latham]

I'm working on tear #3 and am in the planning stages for gas struts with this hatch. On the previous two hatches I've used the star struts. So I've been doing lots of TNTT surfing.

Frankly, I didn't understand how they work. Here's a good informative article I foundon. It addresses the 60º issue and the importance of the seal being stored in oil.

http://www.indgassprings.com/HowDoGasSp ... erview.pdf

Tony

[capnTelescope]

Noseoil has a great post on strut placement. He only touches on the forces involved, but the article is a must read starting point.

[danlott]

I created a spreadsheet and directions on how to determine the proper placement and gas struts to use. Here is a link to my original post.

viewtopic.php?f=21&t=58263

Dan