Dunn and Watson heavy duty gas struts are available in 195mm, 316mm, 430mm, 501mm, 595mm, 700mm and 816mm (full extension). They are also available in a variety of piston thicknesses: 6mm for the smaller struts, 8mm for the medium size struts, and 10mm for the largest struts. The thickness of the pistons increases as the struts get bigger so they can carry greater newtons of force.

So the force of the smallest struts ranges from 100 to 400 newtons, the medium size struts range from 100 to 700 newtons, and the larger struts from 100 to 1200 newtons. So how much weight can your strut really carry? A rule of thumb is that it’s 10kg for every 100 newtons, but you can calculate the exact weight using the calculations on our product pages (seen below under what Gas Struts Do You Require?). This means that our biggest struts can lift a thumping 120kg!

Our gas struts have a black powder coated body and a nitride shaft. This combination means that your gas struts are less likely to collect dust, corrode or chip, compared to chrome struts (great for driving along the beach or in dusty areas). All our gas struts come with the required fittings. When you install the gas struts, make sure that they are not under load so that no-one is injured.

Dunn and Watson gas struts are easy to install and make opening and closing windows, doors and tailgates on Utes or 4WDs a breeze, as well as toolboxes, storage boxes, lift up benches, caravan or RV windows, and camper trailers. With a clever damper function, your doors won’t fly up and smack you in the head! Instead they open gently, giving you enough time to get out of the way. Check out our range of heavy-duty gas struts below.

What Gas Struts Do You Require?

If you need to replace old gas struts that no longer work properly, upgrade existing gas struts because they need to lift a larger weight or you want to install gas struts where you didn’t previously have any, then you need to know which type to buy.

When replacing old gas struts, it’s fairly easy to identify the right struts. You need to know the measurement from the centre of the eye on each end when the strut is fully extended, the diameter of the shaft and the cylinder, and the newton force (usually written on the gas strut). If you don’t know the newtons, you can simply estimate the weight it needs to lift or use the good old broomstick and bathroom scales method. If you have increased the weight the struts need to lift to (usually because you have added solar panels), you just need to know this additional weight to select the appropriate gas struts.

Finally, if you want to install a gas strut to something that didn’t have one before (usually if you are building your own canopy, trailer or toolbox), you need to use a formula, which is shown below. You need to know a few pieces of information to use this formula (call us with this information if the formula seems too complicated). You need to know the dead weight of the door and multiply this by 10 newtons. So if your door weights 5kg, then the dead weight of the door is 5kg x 10 newtons, which equals 50 (G is 50).

Next, you need the measurement for half the length of the door, so if your door has a 1000mm drop, then that’s 500 (so H is 500). Last, you need the mounting distance from the hinge (20% of the door length), so if your door is 1000mm, that’s 200mm (L is 200). You enter these numbers into the formula, and it gives you the minimum newtons force needed by your gas struts. If you call us with this number, we can tell you which gas struts you need.

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Gas Struts - Gas Strut Fittings

Gas Strut Fittings

To make your DIY life easier, Dunn and Watson offer a selection of gas strut fittings. Your gas struts will come with all the fittings you should need, but we have other fittings that you might need at some time in the future. You will receive either a 10mm or a 13mm ball stud (with nuts) with the purchase of your gas struts. You will also receive either a metal end or a poly end, the poly ends come with a brass fitting, so they won’t strip the threads. We use the poly ends for the smaller gas struts and the metal ends for the heavier struts.

Additional fittings you can purchase include a strut eyelet with a zinc plated finish and M6 thread, designed to fit struts with a piston thickness of 6mm. Then we have the Strut Brackets with a round mounting plate, internal mount or angled bracket. The round mounted bracket has a zinc plate finish and 3 x 5mm mounting holes and a 1 x 8mm hole for the ball stud to bolt onto. The round mounted brackets are limited to the 6mm and 8mm gas struts. Otherwise, you just use the brackets that suit the fittings of your gas strut. The Dunn and Watson angled brackets are our most popular of the three types of brackets, because you can use them for either an internal or external fitting.

Gas Struts - Standard Gas Struts

Standard Gas Struts