Gas strut on lazerette hatch question

[PEJ]

The hatch "door" on my lazerette has a gas strut on it and so you have to push it to get it to go down and keep pushing to about half way but after that you have to hang on to it and guide it slowly down or else it slams shut with some considerable force.

Is this normal? Or do I need a new gas strut?

 

[lanerboy]

mine was the same as yours on my Fairline Phantom its a bit annoying really as it really did slam if I let go

 

[PEJ]

Was your Phantom new, that is to say was the strut new?

I wonder if they go loose over time or are they only to assist in lifting the door.

 

[aquapower]

The hatch "door" on my lazerette has a gas strut on it and so you have to push it to get it to go down and keep pushing to about half way but after that you have to hang on to it and guide it slowly down or else it slams shut with some considerable force.

Is this normal? Or do I need a new gas strut?

A gas strut will only work if its positioned correctly, I would check that first as it may be as simple as moving the fixings.

 

[jfm]

PEJ, that's completely normal and there is nothing wrong. In a normal installation, when the hatch is shut the strut lies along a line that passes thru the hinge pin. Therefore it cannot do anything to lift the hatch, as a matter of basic mechanics. Thus, in the closed position the strut is not lifting the hatch at all. When the hatch is close to the closed position, the strut hardly supports it. This is all completely normal with most boat set ups

It is possible to set up a gas strut so it pushes the hatch upwards even in the closed position, but this requires the end of the ram that is attached to the hatch opening to be offset down into the hatch by something like say 100mm. Then the ram no longer lies on a line that passes thru the hinge pin. I have this deliberately on my anchor lockers, so they can never slam shut and have to be pushed down till the catches click, like a small car boot. But it involves extra effort by the builder, and other compromises, so is rarely seen

 

[mad_boater]

If you need a new one try Force 4 cheap as the proverbial chips

 

[PEJ]

Thanks JFM, I understand it now. I've always thought it was a problem with the strut. It is a shame they didn't design it like yours but I guess it would take up space in the opening and then we would complain that they should have moved it out of the way!

 

[Nick_H]

Funny you mention this as I was thinking about it last week. My laz hatch door is very heavy, and if it slammed on someone's foot it could cause a serious injury. I can't move the spring attachment point lower, so I'm thinking of fitting a damper instead.

I found this company who make industrial door dampers, which I think will be suitable. They work like a soft close piston so if the hatch door slips out my fingers, or one of the kids falls against it, then the damper should ensure the hatch cover doesn't slam completely shut, leaving a toe sized gap. It's not a complete answer, and there would still be a scissor action on the sides of the hatch, but I think it protects against the most likely accident.

http://www.slamproof.co.uk/Door-Dampers

I haven't done the maths yet to see which, if any, will be suitable, but they seem to include some pretty heavy duty models, so I think it's likely one of them will work