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rat_catcher
27-05-2007, 08:37 AM
When taking a trailer boat to a weighbridge to get a certificate, what is the correct procedure for getting the proper weight?

Do you leave the trailer connected to the tow vehicle, but only position the trailer wheels on the weighbridge?

Or do you disconnect the trailer from the tow vehicle and use the jockey wheel as well?

The reason I ask is that there will be a few hundred kilos of weight taken by the tow vehicle (downforce on the coupling) and thus when connected to the vehicle I think the weight measured of the BMT will be less than when it stands alone. Is this correct?

Which is the proper way to get the BMT measurement?

krazyfisher
27-05-2007, 09:02 AM
to get a true reading you will have to discount it and use the jockey wheel that is the only way

Brumby
27-05-2007, 09:39 AM
Asked the question of local QLD transport office, when I was looking into setting up to tow my rig. As I understand their answer, for the purposes of the law you take into account only the weight on the wheels, ie have normal weight on the drawbar and put only the trailer wheels onto the weighbridge. You got to ask yourself though, if it's worth trying to skate around the weight limits if thats an issue. Physics is likely to catch up with you somewhere down the line.

krazyfisher
27-05-2007, 10:59 AM
if you are after GVM you need to unhook and weight

Alchemy
27-05-2007, 11:48 AM
I took mine to the Rocklea weigh bridge. Weighed it both ways, ie coupled and uncoupled from the car. When complete they gave me a certificate with all info. Only cost $20. Just look up public weigh bridges in the yellow pages, and you'll find one in your area.

Regards,
Dave.

FNQCairns
27-05-2007, 11:49 AM
The vehicle manufacturer will want to know the total weight of the towed rig so weight it on 3 wheels, the scalies will want to know the weight of the trailer while still attatched to the vehicle so weigh it with on the 2 trailer axle wheels OR the scalies may want to know the entire weight of all combined so weight both separate (doubt they would care though)

cheers fnq

Kleyny
27-05-2007, 03:58 PM
Asked the question of local QLD transport office, when I was looking into setting up to tow my rig. As I understand their answer, for the purposes of the law you take into account only the weight on the wheels, ie have normal weight on the drawbar and put only the trailer wheels onto the weighbridge. You got to ask yourself though, if it's worth trying to skate around the weight limits if thats an issue. Physics is likely to catch up with you somewhere down the line.

Sorry to correct you on this one. but by the law you must disconnect the trailer. Why as this is the correct ATM (Aggregate Trailer Mass). Aggregate meaning the whole thing. If you don't take it apart you are only getting the axle mass.

I understand you have been told by QT but the people behind the counter at the customer service centres no how to take your money and not much more and certainly minutes about the legislation.:-/

You were close to asking the correct people but you should have asked a Transport Inspector.

Neil

rat_catcher
27-05-2007, 03:59 PM
Thanks guys. Sounds like I should do it both ways. Also I know the rig is well over 2 tonnes, so that is not the issue. I just want to make sure it does not go past 3.5 tonnes fully loaded.

rat_catcher
27-05-2007, 04:00 PM
OK given HONKY DORY's response, I guess I will just disconnect it and take the worst case scenario.

Kleyny
27-05-2007, 04:11 PM
The vehicle manufacturer will want to know the total weight of the towed rig so weight it on 3 wheels, the scalies will want to know the weight of the trailer while still attatched to the vehicle so weigh it with on the 2 trailer axle wheels OR the scalies may want to know the entire weight of all combined so weight both separate (doubt they would care though)

cheers fnq

Now we are talking about two seperate things.

1 ATM weight of the whole thing
2 Axle mass weight of the axle only.

You can be fined/ in trouble on both:-/ ;) 1 If the Transport Inspectors or more importantly your insurance company weigh your trailer and find the ATM is over or they weigh it and the ATM is AOK but because the way you have loaded it you axle weight is over.

As you said FNQ weigh the both as if you were going out fishing(eskies, full fuel, and anything else you normally carry)

Hope hope this makes sense.

Neil

Cloud_9
27-05-2007, 04:16 PM
the way i did mine was.
took the car through first. the weight was 2000kg.
then took the car and trialer with boat through.
as i drove through the weight comes up on the scales.
and as i drove through.
the scales showedthe car with trailer attached was 2120 KGs
so that told me i had 120kgs tow ball weight.
and when i got all the trailer on the scales the whole lot weighed 3350Kg's
so the BMT weighed 1360 KG's the trailer tare is 360 Kg's so its just math.
leaves the boat weight is 1000KG's.
just easy.
cheers Cloud 9.

Brumby
27-05-2007, 05:33 PM
Honky Dory, can you point me in the direction of the relevant legislation? I was told that the GTM is the determining factor and want to get this one clear once and for all.

Cheers

Kleyny
27-05-2007, 07:54 PM
For the defintion of ATM/GTM try the Transport Operation (Road Use Management- Vehicle Standards and Safety) Regulations 1999. Schedule 4 (dictionary).

it states: ATM (aggregate trailer mass) for a trailer-

(a) Means the maximum mass, specified by the manufacturer, for the loaded trailer, and
(b) includes any mass imposed on the vehicle towing the trailer when they are in a horizontal surface.


hope this helps

neil

Deiter
28-05-2007, 01:17 AM
the way i did mine was.
took the car through first. the weight was 2000kg.
then took the car and trialer with boat through.
as i drove through the weight comes up on the scales.
and as i drove through.
the scales showedthe car with trailer attached was 2120 KGs
so that told me i had 120kgs tow ball weight.
and when i got all the trailer on the scales the whole lot weighed 3350Kg's
so the BMT weighed 1360 KG's the trailer tare is 360 Kg's so its just math.
leaves the boat weight is 1000KG's.
just easy.
cheers Cloud 9.

Yep, that's the way i did it.
Drove down to the local tip, asked the guy if i could weigh my boat, he says sure, tells me weight of car, then come back with boat (only 5 mins away), weigh car again, then weigh the lot. Slip operator a tener and everyones happy.
No certificate though, but i did get the printout.

FNQCairns
28-05-2007, 06:36 AM
Honky Dory, what definition of the regs would the scalies be weighing if they only weighed the trailer axle wheels in a forced inspection at the side of the road.

All these abstract regulatory definitions get pushed out of my head for important fishing and family stuff, remembering by relating to an action stays put for at least twice as long:)

cheers fnq

rat_catcher
29-05-2007, 08:30 PM
I think I am still confused! ::)

I also now see the trailer has a rating of 3,200kg stamped on the plate. How does that relate?

Kerry
29-05-2007, 09:04 PM
3,200kg stamped on the plate!

To relate this it should also state if this weight is GTM or ATM and based on what "type" of weight it refers then weigh it accordingly.

If it is 3200kg ATM then this is the max weight with the trailer and load sitting on the scales including jockey wheel (totally disconnected from vehicle).

If it is 3200kg GTM then this is weight of trailer and load sitting on the scales, axles only (towball down weight not included).

Regards, Kerry.

rat_catcher
29-05-2007, 09:24 PM
If it is 3200kg ATM then this is the max weight with the trailer and load sitting on the scales including jockey wheel (totally disconnected from vehicle).

Understood. It is ATM. Thanks.

Kleyny
29-05-2007, 09:55 PM
In the regulations stated earlier the GTM is

GTM (Goss Trailer Mass) means the gross transmitted to the ground by the axles of a trailer loaded to its GVM and connected to the tow vehicle.

Altough confusing i think Kerry is correct.

FNQ I have not forgot about your axle question i just havent found it yet.(not as easy as the ATM & GTM.)

neil

Clearly dont get the two mixed up. Without seeing the plate i would dare say the 3200 is ATM.

Kleyny
29-05-2007, 10:11 PM
Honky Dory, what definition of the regs would the scalies be weighing if they only weighed the trailer axle wheels in a forced inspection at the side of the road.

All these abstract regulatory definitions get pushed out of my head for important fishing and family stuff, remembering by relating to an action stays put for at least twice as long:)

cheers fnq

Try, Transport Operations (Road use Management- Vehicle standards and safety) regulations 1999.
Part 1 section 5(1)(c)

(1)A person must not drive or park or permit to drive or park a vehcile on a road if:
(c) the vehicle is not constructed or loaded to comply with the vehcile standards.

its amazing what you can find when the kids have gone to bed;D

hope this helps

neil

Kerry
30-05-2007, 10:22 AM
FNQ,

A normal roadside operation will only be weighing the trailer axles anyway and perhaps the vehicle "as connected" if they get interested in GCM. The GTM (axle load only) will be generally enough to determine if the thing is overloaded based on ATM.

What you have to watch with some suspension systems is that it is impossible to determine GTM on some multi axle trailers with only one set of scales. If they try this you will go way over your actual weight.

Also the transport scalies actually have no official jurisdiction for vehicles/trailers under 4.5 tonne as this is a police responsibility. So the police have to invite the scalies to the party.

Regards, Kerry.

FNQCairns
30-05-2007, 11:13 AM
Thanks fella's for the replies, Kerry great info thanks, I suspect the roadside DOT inspectors can do the lower weight trailer inspections.

I have a 6.1 overall tinny on a single axle trailer but I am way under, just doesn't look like it, suspect they will check me sooner or later.

Thanks fnq

Kleyny
30-05-2007, 12:08 PM
FNQ,
Also the transport scalies actually have no official jurisdiction for vehicles/trailers under 4.5 tonne as this is a police responsibility.

Regards, Kerry.

What gave you this impression.

In the transport act it states a Authorised Officer (Transport Inspector) can intercept/ stop private vehicles (under 4.5 tonne).

neil

Kerry
30-05-2007, 02:55 PM
What gave you this impression.

In the transport act it states a Authorised Officer (Transport Inspector) can intercept/ stop private vehicles (under 4.5 tonne).

neil

Oh that's not an impression, you will get that answer from any of the transport scales people. When things like boat trailers get targetted weight wise there will always be traffic or water police present, the scalies are there by request only, not their own doing.

Regards, Kerry.

Kleyny
31-05-2007, 10:18 AM
I'm not going to argue with you Kerry you said scalies have NO JURISDICTION on vehicles under 4.5 tonne on which you were wrong.

BUT yes the water police would invite/ request them to the boat trailer "party".
As I'm sure they have better things to do than weigh boats that are a little over weight.

neil

Kerry
31-05-2007, 10:48 AM
I'm not going to argue with you Kerry you said scalies have NO JURISDICTION on vehicles under 4.5 tonne on which you were wrong.

BUT yes the water police would invite/ request them to the boat trailer "party".
As I'm sure they have better things to do than weigh boats that are a little over weight.

neil

If you want to quote neil, then at least have the decency to quote the context and not be selective. There is nothing WRONG neil with what I previously said.



Also the transport scalies actually have no official jurisdiction for vehicles/trailers under 4.5 tonne as this is a police responsibility. So the police have to invite the scalies to the party.

Kleyny
31-05-2007, 10:59 AM
Ok
i must be reading you sentence wrong.
I read it that Transport Inspectors/ scale people have NO authority to deal/ intercept vehciles/trailer under 4.5 tonne. thefore thats why the police invite them to the boat ramps to weigh your boat and trailers.
is this what you mean????

Kerry
31-05-2007, 11:12 AM
In simple terms it does go something like that.

Kleyny
31-05-2007, 11:24 AM
In the transport act it states a Authorised Officer (Transport Inspector) can intercept/ stop private vehicles (under 4.5 tonne).

neil

So i revert you back to this.

I'm going to stop beating my head against the desk now. If you dont think Transport Inspectors have the Aurthority to pull you over this is up to you.
But if/when they do decide to intercept you (for what ever reason) and you dont stop expect a fine. ;)

neil

Brumby
31-05-2007, 01:42 PM
When taking a trailer boat to a weighbridge to get a certificate, what is the correct procedure for getting the proper weight?

Do you leave the trailer connected to the tow vehicle, but only position the trailer wheels on the weighbridge?

Or do you disconnect the trailer from the tow vehicle and use the jockey wheel as well?

The reason I ask is that there will be a few hundred kilos of weight taken by the tow vehicle (downforce on the coupling) and thus when connected to the vehicle I think the weight measured of the BMT will be less than when it stands alone. Is this correct?

Which is the proper way to get the BMT measurement?


Been doing a little light reading on the subject and although I still haven't found chapter and verse in the relevant legislation, did find a handbook on trailer towing on the QLD Transport website.

Seems that for the purposes of deciding whether you need brakes (750kg) or a breakaway system (2000kg), you use GTM, ie weight on the trailer wheels when hooked up. To decide whether your vehicle is legal to tow a trailer, you need to look at the ATM, ie unhitched. If you really want to be sure you are ok, check the GCM, ie the whole shebang, tow vehicle and trailer together.

As I say, can't quote you the relevant section numbers of the act, but hopefully QLD T'port have gotten it right in their handbook.

rat_catcher
31-05-2007, 08:34 PM
Seems that for the purposes of deciding whether you need brakes (750kg) or a breakaway system (2000kg), you use GTM, ie weight on the trailer wheels when hooked up. To decide whether your vehicle is legal to tow a trailer, you need to look at the ATM, ie unhitched. If you really want to be sure you are ok, check the GCM, ie the whole shebang, tow vehicle and trailer together.

Thanks Brumby. I think this is the simplest explanation I have had so far. Can you point me to a link to that hanbook?

rat_catcher
31-05-2007, 08:37 PM
Can you point me to a link to that hanbook?
I think I might have found it. Is it called Safe Towing and has a picture of road with two cars pulling caravans on the front?