Towing questions

[barbarab]

Hi,
our van is finished and ready to go but now I have a few questions about towing it.
We calculated a towball weight using the bathroom scales as suggested in various articles and came up with a weight of 162kgs. This is for a 15-16ft Franklin Freeway. Does this seem right? Can it be altered by placing the spare wheels behind the caravan axles to lift the nose, or isn't it necessary?
Is heavier on the towball better than lighter? Is there an optimum weight to aim for?
The chains that fit into the slots on the weight distribution bars fittings - are they fastened in any way or does the weight of the caravan hold them in position? How do you know how far up the chains to position it?
Do you just make it as tight as you can?
Sorry - probably simple questions to you but we really don't know about this aspect of it.
Barbara B

[Franklin1]

G'day Barbara,

Interesting questions...and sure to get a number of different responses.


Ball weight...

Firstly, let me get picky about the length of your van. The Freeways were built with a length of 14ft 9ins, as measured from the flat face of the front windows to a vertical line in line with the bottom curve where your number plate bracket is. (Simple, innit??! )

A 14ft 9ins van should have a theoretical tare weight of approx 767kgs (14.75 x 52kgs), giving a recommended 10% ball weight of about 77kgs. Actual tare weight can be higher, depending on what's in the van when you weigh it (full gas bottle, spare wheels, curtains, bedding, water tank full?, etc) so even if we threw in another 100kgs, that would make your van have a tare weight of, say, 870kgs (My 14ft Millard is 820kgs, and has a ball weight of 84kgs).

The rego authorities typically allow a loading allowance of 300kgs for a single axle trailer (van) and 400kgs for a tandem axle van, so your van could end up with a Gross Vehicle Mass of 870 + 300 = 1170kgs (They gave my Millard 1200kgs). So even with a fully loaded van, your ball weight shouldn't be more than 120kgs.

You might want to double-check your test. Did you subtract the weight of anything weighing on the scales before you lowered the drawbar down onto the balance? If you took the two spare wheels off their holding brackets, what reading would you get? Is it still higher than 120kgs 87kgs? Ok, then take the gas bottle off, and do the test again. What reading now? By the time you take the spare wheels and gas bottle out of the equation, you must surely be down below the theoretical 87kgs mark for your van.


The following photo shows how I did the test for my van, with the beam balance in the left photo. The weight of all the timber on the scales is subtracted from the total weight reading after the drawbar is lowered down (and then the nett weight is multiplied by 2)...





The question of setting up weight distribution hitches is something you can worry about after you've got the ball weight issue sorted out, I feel.

cheers,
Al.

Oops, I had to come back and modify my ball weight figure from the fully loaded 120kgs to the 87kgs tare weight figure.

[barbarab]

Thank you Dave and Al.
When we weighed it the first time, it had a big lump of metal on the drawbar for the anti-sway gear which we've removed. We also didn't have the gas bottle in place on the front as we won't be using it, and we'd removed a double bed frame and a pair of bunks from the back of her. The bedframe in her now is lighter too. I don't know about the water tank - I'd guess it's empty but we'll check.
We'll weigh her again this afternoon and get back to you.
Barbara B

[Franklin1]

G'day again, Barbara

Note I've made a correction in my post above, about 2 mins after you replied above.

cheers,
Al.

[barbarab]

Hi Al,
is the drawbar supposed to be horizontal, or at the height of the towball on the tow vehicle, or doesn't that matter?
Barbara B

[barbarab]

Hi,
we took the spare wheels off the front and weighed it directly onto the scales and came up with 120kgs. Is that still too much?
Barbara B

[Franklin1]

G'day Barbara,

Are you sure a previous owner hasn't poured a concrete floor in your van at some stage??!!

At least we are heading in the right direction if you are now getting 120kgs, but gees that still seems high for a van such as yours.

I've pinched a couple of photos of your van from another thread, so that other readers will understand the van we are talking about...






I'll also put a link here to the other thread on the forum about ball weights and how to use the balance method:

Ball weight


The other thing that would be useful is for someone like curtis to come on here and tell us what the tare weight, ball weight, and GVM of his Freeway is.

---------------------------------------

Ok Barbara, back to your van. To my way of thinking, 120kgs ball weight is still unusually high for a van such as yours. However, the 'experts' will say that while 10% is the aim, anything up to 15% would be acceptable. Anything under 10% should be avoided. If we assume your van has a tare weight of 900kgs, then a ball weight of 120kgs is just over 13%.

It is best to do the beam balance test with the drawbar horizontal when resting on the beam (it probably doesn't matter if it's slightly out of level, but we're trying to simulate the van being hooked up to a level towcar/van combination when we do the test). If you look at my photos in the other post above, you'll see a spirit level partly hidden behind the jockey wheel, and resting on the drawbar.


The crucial piece of information missing from this discussion is, what is the actual tare weight (unloaded weight) of your van, when it is unhooked from the towcar? Without knowing that, we are really in the dark as to whether 120kgs ball weight is too high or not. Getting your unloaded van weighed is probably the next step towards sorting out the ball weight issue, as well as the other issue about weight distribution hitches. To get a 'fair dinkum' tare weight, you should try and weigh the van as if it had just come off the production line. No spare wheel/s, no gas bottle, no annexe/poles, no water in the watertank, etc. You can leave the curtains in , but take anything else out of the cupboards/drawers/wardrobe that might be stored there.

Obviously you'll need to tow the van to get it weighed, so in order to temporarily reduce the ball weight further for that towing trip, you could place the two spare wheels inside the van as far to the back as possible. Lean them up against the back wall if you can manage that. Each spare wheel weighs about 15kgs, so you would have another 30kgs in the rear counteracting the ball weight at the front. Just remember to take the spare wheels back out when you do the actual weighing.

cheers,
Al.

[barbarab]

Hi,
she measures 15.5 feet measured as you said above, so she's a bit longer than Curtis.
Barbara B

[Franklin1]

By golly, that's true! And my humble apologies to you as well!!

I checked through my records, and indeed there was a 15ft 6ins model available in early 1966 (which is when your van 1036-6 was built)...




Up until that time, the Freeways appear to all be 14ft 9ins. The 15ft 6ins model doesn't seem to have hung around for very long, although the history gets a bit scratchy because the Caravelle model was launched that year and the van lengths for the various models change as well.

Anyway, I stand corrected. It would mean your van has a theoretical tare weight of 15.5 x 52kgs = 806kgs. Still well below the sort of tare weight I would expect to cause a ball weight of 120kgs, though.

cheers,
Al.

[humpyboy]

G'day Al and Barb, I've been watching this thread with a little intrest to see where it goes (not to busy here ) just thought I would make a point of mentioning the re- arrangement of the beds that Barbra mentions in reply #3, I was wondering how much difference there would be between the weight of the old bed and bunks as opposed to the new replacement, if the new bed is much lighter than the old ones that were removed would this not put more weight to the front? thus making the drawbar weight higher?

[Franklin1]

G'day humpyboy,

Yes I did note Barbara's information about the rear beds, and it's looking like that change has had a significant impact in the overall weight ratio of "for' and aft" in the van.

Barbara says they removed a double bed base. If it is anything like the metal double bed base in my Millard, it's a bloody heavy mongrel...




I never weighed it, but I struggled to get it out of, and back into, the van during the resto. I would estimate it to easily have a weight of around 40kgs or more.

Plus, who knows what sort of weight was involved in the double bunks in Barbara's van, so the rear half of the van could be pretty sparse with weight now.

If there's not already a concrete floor in the van, Barbara might need to pour a slab in the rear half to compensate for all the weight taken out.

cheers,
Al.

[humpyboy]

I've got a mixer she could borrow ;D ;D ;D

[barbarab]

Hi,
the previous bed and bunks were made of quite heavy material. There wasn't a metal frame, it was all timber. Tony's going to weigh them today. I think you're right - this is what has happened. The new bed frame Tony made and the new mattress are quite light. I guess when she goes on the road, we'll just pack everything to the back to correct the towball weight. Is it OK to do that?
Thanks for the offer of the concrete mixer but we'll try to do without it. :-) :-)
Barbara B

[seeshell]

Hi Barbarab

Before you guys get out on the open road - piccies! Show us your handiwork!

Cheers
Seeshell

[barbarab]

Hi,
the beds' frames weighed almost 50kgs.
Seeshell, yes, I have some photos for you. I'll put them up shortly.
Barbara B

[humpyboy]

Hi Barb, you probably no longer have it but if the old mattress is still around you could weigh this also then weigh all the new stuff you put in and then work out the difference between the two and it will give you a better idea of just how much extra weight was put to the front of your van.

[barbarab]

Hi,
the mattresses in it were just light foam. I would think our new innerspring mattress would be slightly heavier, but there wouldn't be much in it.
Something else that affects the balance - we removed the old heavy three-way fridge and put in a modern light bar fridge, but to counteract that , we put an airconditioner on the front and that's about 30kg.
Barbara B

[Franklin1]

I've copied and pasted some information from this other thread into here. It provides more information for consideration...

Jun 19, 2011 19:21:36 GMT 10 JBJ said:

Hi,

At the risk of being my normal self, who really doesnt care much about the "RULES", I think you should forget all you have been told about drawbar weight. Just hook your van up, & take it for a tow along a reasonably straight & level road (if you have one near you).

See how it tows, slowly increasing speed in short sections, till you get it up to the speed you feel comfortable towing with. I will bet you dont have any problems.

I wont use leveller bars, & I've towed a lot of different vans & trailers.

I go back to being a teenager, when my Dad towed 14' ply vans behind an FE Holden, with Mum & 4 kids as passengers.
Guarantee that a mile or so on the road the van started swaying. Dad stopped, had a blue with Mum about all the crap she packed in the overhead cupboards. She then re packed the van, & off we went for several weeks without a problem. Didnt go real fast, but that showed me how a van can be tempremental when packed wrong.

Over the following 50 odd years, I've found trailers & vans react to how they are loaded.
I've never checked drawbar weight on anything. I've had vans I can lift at the front, & some I cant get off the ground by hand.
They all establish their own comfortable towing speed.

Some you can tow at 120 plus kmh, without a wobble. Some are comfortable at 100 kmh. Some less. Different sized tow vehicles, different height tow balls, all make a difference.

So my idea is try out what you have. It may not give you any grief as it is. If it does, then toss your spare wheels, & a bit of a load in the back of the van. Test it to same speed & road. If its better, that gives you some ideas where to stack the weight.
If not, put the load to the front & try it.

Vintage caravans werent designed on computers, & a hell of a lot were homebuilt.

Find out what works for you, Then go & enjoy the best fun you will ever have.

Its all fun if you let it be.

JBJ

And this...

Jun 19, 2011 20:58:28 GMT 10 Roehm3108 said:

Hi. Great pics of a fabulous transformation - congratulations on all your work. Now go and enjoy the fruits of your labours.

I've been following the whole debate on ball-weights etc. Of course adding the aircon hasn't helped your problem I agree with what Al said somewhere along the track, get the van weighed, to see if your calcs are right. As long as your car has the towing capacity, I also agree with what JBJ advised - go out and enjoy the van ;D ;D The only thing that JBJ and I disagree on is the matter of anti-sway bars. I feel thay DO help you control your van better, especially when those huge B Doubles pass you, as no amount of correct packing will overcome their pull. For what they cost in the whole scheme of a caravan investment, it's a small cost for added safety - and these days every little bit helps.

Ray