Topagee Camper: The Weigh in

9:48am Thursday 6th of January 2021
It's Thursday morning as I arrive to a green tin shack on the side of an agricultural warehouse in Kyneton. Framed by two rusty stakes in the dried out grass, I peer through the damaged window and see that there's nobody there. A part of me wonders whether I should just leave, but it's been a pretty long drive and I'm keen to get the Topagee weighed. Just then a decent sized truck pulls up and the driver gets out and starts walking towards me. "I found you on Google" I say, "Do you weigh trailers?". "Sure thing mate, it's $20". Let's do this.

Lived to tell the tale.

It's been a month since we got the Topagee and since then I've given it a once over with fish oil, acrylic spray and grease and we've taken it camping to test it out. But one thing we haven't done is weigh it. If you trust the registration details, it should weigh about 300kg but this trailer was built in 1980, and I'm sure things have been added and parts have been lost since then.

Why weigh a trailer?

The Topagee is unbraked which means legally (and for safety) it needs to be under 750kg to be towed by my car (Nissan X-Trail SUV).
The tow-ball weight - which is the amount of weight pushing down on the cars tow-ball as opposed to the amount being pulled - needs to max out between 50kg and 200kg depending on how loaded up the car is.
What I really want to know is how much room do I have to play? Can I beef up the plywood floors (which have started to collapse in) and still be under weight? Can I put a slide in, electronics, a battery? How much water can I carry?

So how did it go?

First things first, you should know that I loaded the Topagee up with all my current camping gear basics. A table, chairs, cookers, plates, mattress, pump, spare tent - all the good stuff. I wanted to make sure the trailer was at 'worse case scenario' weight. I had a chat to the attendant and made sure we'd get 3 weights.

The weight of just the car, without me in it.
The weight of the car, connected to the trailer - without the trailer on the scales (to get the tow-ball weight)
The weight of just the trailer, disconnected from the car.

And the result ...

Car only 1.73 tonnes
Car + Trailer 1.78 tonnes
Trailer only 470kg

Doing the math

Trailer weight (pulling weight)

At 470kg we still have another 280kg before we reach the legal limit of the trailer. That's good news but it still means we'll need to be careful with material choice - a lot of the things we're doing to the trailer will involve wood and wood weights can add up quick.

Tow-ball weight

This gets a bit more complex because of the way my car works. The trailer came in at 50kg ball weight (1.78 tonnes - 1.73 tonnes from the measurements above). On the inside of the drivers side door, there's this handy guide about tow-ball download weights.

The GVM of my car is 2,100kg and without me in it at the weigh-bridge they have it at 1,730kg. It wasn't completely empty because it had my fridge and solar battery setup in it - which add up to around 80kg - but those things are permanently installed in the car so I figure they contribute to empty weight.

That means the car, empty, is 370kg under GVM. Most of my camping gear lives in the trailer so when we go on an adventure it'll be me + my partner + my dog + some personal items. We're all pretty small so that adds up to around 200kg. That means we are 170kg under GVM. Using the guide above that means we should be able to put around 150kg onto the tow-ball. Success! That means we've got another 100kg to play with - but what that realistically means is that we can add a couple of bicycles and a water tank to the front of the Topagee without over-stressing the car. It also means that if we were carrying another couple of adults (and their things) we'd want to keep the front of the Topagee as light as it is now at 50kg.

Moving on

We now know we've got an extra 280kg to play with, of which at least 100kg can be front-loaded in the cage close to the tow-ball. Mission complete.

I recorded a bit of a video about how it all went down that includes the calculations.