Gas struts for engine lids

[wetbuoy]

I am trying to put a pair of gas struts on each engine lid for safety. Attwood used to do the calculations but no more (thanks a lot). there are way too many variables for trial and error, so I'm hoping someone knows how to do the calculations. Just in case, my two doors are about 40 lbs each, distance from hinge to opposite side is 45", and the door travel would be from horizontal to 100 degrees. So I can't figure the strength or length or positioning of the struts. I may end up making a strut out of dowel and tubing and a hinged frame in the toolroom as a template. I just realized that might work. Will let you know...
Thanks for any help.
wetbuoy (F28)

[gitchisum]

Try here, it a friend of mines company and you can search on the three parameters

http://www.allegiscorp.com/products2.aspx?id=19&acc=0

[larryeddington]

Boy that is something I have been giving thought to, at least a little. My f28 hinged doors are definitely heavy, especially with sound deadner on the which is going away.
I also have thought of screw jack or electric/hydraulic openers. Thanks for asking the question as I need the answer also, my boat is about 1 to 2 weeks from going back in water.

[wetbuoy]

Larry and gitchisum,

I'm making progress on the struts but what a hassle. I am just waiting to hear back from a company and will post you when I hear.
I only had the 42.5 lb door fall on my head once last season. Did I say I love this boat?
FYI I have just bought from Hot Spark Ignition 2 electronic ignition kits for my 225 MerCruisers. Cost about 65 USD each. fitted them but not installed yet though simple enough. When I got the boat there was a box full of points, condensers, caps and rotors, all useless and burned. Just change the entire points plate and retime the engine. So off we go into the 21st century...

[wetbuoy]

Follow up. McMaster-Carr won't help with retail sales, especially Canadian. US commercial only. No go with Attwood Marine. Industrial Gas Struts was a strike out, and Guden Hardware uses the same diagram as JR Products. Next try will be gitchisum's friend.

[larryeddington]

Good luck, my f28 has rods that prevent the heavy hatch from falling, if I use them.

[hanybop]

I would try looking at some automotive door struts, they should have a load rating/stroke printed on them, all you would have to do is figure out your stroke from closed to opened and find a minimum/maximum size you can work with, and you wouldn't have to get a 40+ pound strut I would go with a load rating of 40-60% of the door weight at max, because all you need is the door to stay opened, in my thinking if you get a strut that's powerful enough when you hit a wave that door will fly opened, have a look in Canadian tire they have a whole section of them.

hope this helps

Paul

[wetbuoy]

I finally made some progress. None of the companies I tried would help and now I see why. I finally called a machinist friend who designs odd machines to get his input. He said he knew exactly how to do it and it would only take one visit for measurements and a solid 2 hours on his $30K+ autocad design program his company uses. I was starting to think that this might be the case... Anyway he agreed it would be a good idea and is working on it. This is going to cost me some serious beer but it will be worth it. If it goes well (it will), I'll ask his permission to pass along the information.

Stephen (wetbuoy)

[larryeddington]

Here is a copy of article from Boat U.S Magazine June/July 2014 regarding how to rig power hatch openers. http://www.boatusmagazine.com/boatusmag ... y_2014#pg1. Well software would not let my upload a PDF the article starts on Page 88, anyway.