I'm looking to put a gas strut onto the bonnet of my car, but I don't like the design of the kits you can buy so want to do my own.
All I need to know is what sort of force struts I need, either as a single or a pair.

Thanks.

My son used one from a Suzuki Swift rear hatch on the Countryman.
It works well, but is probably a bit bigger than is required.

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Too many cars, and too little time.

Funny concidence, I've been looking at gas struts for the upper tailgate of the enclosed trailer I'm building.

The lowest spec ones have 100 Newtons of force or around 10kg. That should be plenty for a Mini bonnet. It's just a matter of working out the extended length you need and making up a couple of brackets.

They normally come as a pair on eBay for $15-40 plus post. Or raid a wreckers for one from a small rear hatchback. There was some on a Micra at Centre Rd last weekend that looked about right.

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Brett Nicholson
Greendale (near Ballan) VIC.
1971 Morris Mini Moke
1966 Austin Mini
1965 Morris Mini Traveller
1973 LR Series 3 88
2007 LR Freelander 2

I just want to make sure I start with the right struts.
If they aren't strong enough they're pointless, if they too strong the bonnet will bend when it's closed.

I hear you, but how do you measure the force you need?? Maybe use a spring balance to measure the force required to hold it open? You may have to do some experimenting on this one, bonnets and hatches on any other car would weigh more than a Mini bonnet.

I had a Gemini fail RWC years ago because the boot did not stay open by itself (it had a rear spoiler). So I grabbed a gas strut from a Commodore wagon at the wreckers and fitted that. I could barely close the boot-lid and it flexed massively. I had to take the strut to a place that regassed them and have them let some gas out.

100N seems to be the lowest spec, so I would be surprised if you need anything stronger.

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Brett Nicholson
Greendale (near Ballan) VIC.
1971 Morris Mini Moke
1966 Austin Mini
1965 Morris Mini Traveller
1973 LR Series 3 88
2007 LR Freelander 2

The force can be worked out, all you do is take the weight and centre of gravity of the bonnet and multiply it out to suit the reaction point of the load. An appropriate angle calculation at maximim lift will tell what is needed to hold it open.

The easier and more accurate is to take a scale and put it in the engine compartment or as you say, check with a spring balance.

Pssst Harley I think your engineer bits are showing

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There is a gas strut supply/re gassing business just off Sydney rd in Falkner, just around the corner from Minitopia. I have used this guy for many years and he will be able to help you with whatever length strut you require and can adjust the force (by changing the gas pressure) to your requirements.

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Have a Nice Day.
If already having a nice day please disregard.

I think you will have to work it out and be the trail-blazer on this one. You know more about it that me. I think I will use a regular scale and a stick to check the force required for my tailgate.

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Brett Nicholson
Greendale (near Ballan) VIC.
1971 Morris Mini Moke
1966 Austin Mini
1965 Morris Mini Traveller
1973 LR Series 3 88
2007 LR Freelander 2

Lazy people.

If you want to go twin struts, try a 4wd place that does fiberglass canopies, the struts for the windows on them are very light.

Tip for strut mounting, when the bonnet is in its closed position, the fat end of the strut should be higher than the thin end, even a couple of centimetres will do, this keeps oil on the seal. Otherwise they get sticky and noisy

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Dean Hutton's first car was a Mini.

Yeah, that's exactly what I meant by a spring balance Cush!

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Brett Nicholson
Greendale (near Ballan) VIC.
1971 Morris Mini Moke
1966 Austin Mini
1965 Morris Mini Traveller
1973 LR Series 3 88
2007 LR Freelander 2

hehe.. I quoted (and only read) the wrong line..

I've played around with gas struts before. On one job I had a steel door 1800 wide and 1750 high that weighed 75 kilos and I had to put 2 struts on it strong enough to lift it but still let a person close it. I cocked up the first time, door opened fine but I couldn't close it because I'm not heavy enough!

Had the struts re-gassed and it runs fine now, but you do have to stand back when you open it on a hot day as the struts have a higher load rating when they're hot, and the door opens very quick!


When I get into the strut setup for the mini I might investigate the stresses on the parts.
Depends how bored I get.