Hatch Gas Spring/Strut Calculator

[dales133]

Thanks I'll try it again first

 

[danlott]

Hi Dan, thank you for making this calculator! Question, if I reverse the mount points so the outer mount point is on the hatch and the inner mount point in the galley, will the calculations be the same? Any reason not to do it that way? I read somewhere it makes the hatch more stable, especially in wind.

Thanks,
Doug

There are lots of ways to mount the struts and your idea would certainly work. I do think the calculation spreadsheet would work, just make sure to enter the correct measurement for the "Spring Attachment to Hinge Center Point in Inches". This is the measurement of the connection point of the strut to the hatch.

Dan

 

[dales133]

do we have a maths?conversion wizard in the house that could help me with 5 minutes of thier time please!
im trying to work out my calculations and im terrible at maths and even worse with imperial measurements.

Edit.
The mrs worked it out but the struts i found are in nuton meters not pounds like in the calculator... this is doing my head in.
How do i convert nm to pounds of force,i dont even have the vaugest idea

 

[noseoil]

It's fun, isn't it? Here's a link to something you can use. Basically 1 NM = 3/4#, actually .73# but close enough for what we do normally.

http://www.unitconversion.org/energy/ne ... rsion.html

 

[TomMaj]

Dan-
Spot On!! Thanks for making the calculations, it worked perfect first time. Bought 50lb and 29" - Auto lifts by itself and shuts with around 5 lbs push.Feels the same as my SUV hatch. I would have wasted a bit of cash without your work.

 

[derekbudd-TNT]

I just installed struts on my new trailer following the calculator and it worked great the first time. I ended up with 28 inch 50# springs.
Thanks for the information.

 

[Kanook]

Worked perfect for me too. I went on the cheap. Spent about 30 min and $10 digging through a pile of new lift struts at a freight salvage/over goods store till I found two matching that fit the requirements and then used scrap metal I had and welded my own mounts.

 

[Paradiseteardrop]

Hi I used the calculator for my Benroy hatch. It worked out to 80 LBS. LIFT IS PERFECT. After starting with 2- 40# I worked up in 10# stages and it ended up with 2- 80#. This was the figure I got in the first place. The lifts were in 10# stages at the RV store. Just round out the figures you get. 1.6123.-- 6 is over 5 so it can be a 2.000. Work out the figures shown a couple time then do with your figures.
Take care where you mount the bottom of the lift. 8-1/2 from the hinge pin. Lift the hatch to the height you want. Wacks on the forehead you do not want . Swing the bottom back to clear the hatch and mount.
Now to try and figure out how to load pictures here. This is my second one with FRP skin . Lee

 

[Strop]

Hi all,

Just using the calculator, Dan thank you very much for this BTW , but I have a question.

a
After doing all the calculations I come out needing 97lb gas springs, that need to be 33.6 Inches long. Now my conversion for that is 430 Newtons and 853mm. The closest match I can find is 500N (112 lbs) and 830mm (32.7").

Will 112 lb gas springs be too much? I can see that a safety margin of 50N has already been added in.

I can get struts that are 400N (90 lbs) that are 816mm (32.16") long.

Are they too small?


Thanks

 

[danlott]

Sorry I have not been online much in the last year. I am happy that this calculator has helped so many people.

Sometimes the ideal spring lengths and weights for your hatch may not be available. If this is the case then I would do the following.

1. Using the calculator, adjust the "Stroke Length of Gas Shock" of the springs that you locate that are as close as possible to the ideal length and weight of what the calculator suggested.

2. Then adjust the "Spring Attachment to Hinge Center Point in Inches" based on the "Ideal Spring Attachment to Hinge Center Point in Inches" calculation.

3. The new "Spring Attachment to Hinge Center Point in Inches" value will adjust the "Required Force of Gas Springs in Pounds" value.

Play around with these numbers and compare them to the various springs that you are able to locate. You should be able to come up with something close that will work.

Dan

 

[TimmyNY]

Used the calculator last weekend for my hatch. It worked perfectly. . 31 inch 80 lbs struts that I bought on Ebay. your measurements were perfect. only took 10 min to install them. look for strut-your-stuff-here on Ebay. they have all kinds of strut lengths and weights and hundreds of different brackets picked up everything that I needed for $70.



Tim

 

[danlott]

Used the calculator last weekend for my hatch. It worked perfectly. . 31 inch 80 lbs struts that I bought on Ebay. your measurements were perfect. only took 10 min to install them. look for strut-your-stuff-here on Ebay. they have all kinds of strut lengths and weights and hundreds of different brackets picked up everything that I needed for $70.



Tim

Happy to hear this Tim.

Dan

 

[Almighty Ed]

I bought some hood struts from a 90's Cadillac at the junkyard for $5. The calc said I needed 27" but these were only 24". Used the pivot point calculations and they still work great. Thanks for the help!

 

[ratrod71]

Installed the hatch struts finally. Another item checked off the final to-do list. I used 20" struts rated at 100 lbs. Distance from hinge pivot point to upper ball mount is 7.25". I used the hatch strut calculator on this website and it worked perfect. Wahoo! Bryan

 

[Redneck Teepee]

Installed the hatch struts finally. Another item checked off the final to-do list. I used 20" struts rated at 100 lbs. Distance from hinge pivot point to upper ball mount is 7.25". I used the hatch strut calculator on this website and it worked perfect. Wahoo! Bryan

Looks very nice Bryan!

Makes life easy doesn't it. I use those on almost every lid I have to lift open (almost) Just installed them on my 40 Ford Coupe trunk lid...80 pounders did the trick

 

[danlott]

Installed the hatch struts finally. Another item checked off the final to-do list. I used 20" struts rated at 100 lbs. Distance from hinge pivot point to upper ball mount is 7.25". I used the hatch strut calculator on this website and it worked perfect. Wahoo! Bryan

I am glad the calculator helped you.

Dan Lott

 

[tpavlusik]

My design will not allow to install the lifts as the calculator recommends them. Is it possible to install longer struts than calculator is calling for and if yes how should they be installed (placed).
Thank you.

 

[TallyTear]

Could someone help me find the calculator download? I am sure it is right in front of me.


Sent from my iPhone using Tapatalk

 

[Breytie]

First post of this thread on the first page, just below the installation / measurement pic!
http://www.tnttt.com/viewtopic.php?f=21&t=58263#p1052800

 

[Thommyknocker]

TA huge thanks to Dan Lott

Another perfect install!

I followed the instructions and it went like a dream.
Just had to fab my weird lower mount, and Bob's your auntie