Best method to extend a caravan drawbar

[TurboRA28]

Howdy, we've got an old 70s viscount caravan that has a stupidly short drawbar. i would like to extend so can mount some pushbikes on it. so not much weight 25kg extra or so.
Trying to work out best method.
either cut existing one off completely and use new 50x100 rhs.
Build a new one kinda alongside the existing one welding along the length of it but as it gets longer the angles etc Will create a gap at some point between new and existing so couldn't weld entire length.
Or i could use some C shape metal and weld it onto the existing bar wrapping around it kinda.
Might need pictures to help those ideas make sense.
Ideas?

[Glenno]

Cut the old one off and replace it.

[carcrazy]

Longer drawbar?

[Momus]

Photo would help here..

[nine2nine]

Cut it off, and weld on new one. The only way it wont look really bad, and probably the easiest way too.

[TurboRA28]

Will get some photos to confirm plans.. What is the usual wall thickness in 50x100 for a drawbar these days?

[TurboRA28]

[Momus]

Fuckin short all right, would be a cunt for jack knifing on turns..

OK, drawbar weight should be only around 100 Kg max so a massive structure is not required.
Prime coated rhs is 350 Mpa minimum which is handily strong. I'd go for 3 mm wall in that 100 x 50 section.

As far as extending it goes you could look at letting a suitable piece of 100 x 100 x 3 in between the apex of the two legs of the 'A'.
The hitch should fit that and be secure if you crush tube the mounting holes.

[sean]

Check what your drawbar weight is by sitting an axle stand on a bathroom scale. Some caravans have stupidly high drawbar weights to compensate for other design flaws and stop them getting the arse wobbles when they're towed.

If it's already heavy adding gear to the front will make it worse, better to put the bikes on the back

[Cracka]

Cut the cuts out of the existing towbsll mount. Weld length of 100x100 in and gusset appropriately to existing bar angle. Weld new hitch into top of 100x100. Will look like a 'A'with an 'I'in the middle and out the top.

[TurboRA28]

Like this? Red being new bit.

[TurboRA28]

Or like this but not as long and with it extended back more..

[myliberty]

Like the MS paint mockup. Probably doesnt even need to extend further than the start of the van. Did it to bosses caravan years ago. Cracka

[TurboRA28]

So the forces on the extension are only up/down for the weight of the van.. as the towball swivels around anyway so cant be much side to side force on it. ?

[Dave75]

10% of the van/trailer weight is the usual accepted tongue weight.... 1500.kg trailer=150kg tongue weight.& van loaded properly is more important.

[TurboRA28]

Hey what thickness wall in the 100x100 do you reckon? I was going 4mm but think it might be bit heavy/overkill.. Would 3mm suffice?

Edit.. everyone already told me 3mm.. So 3mm?

[TurboRA28]

Hey all, decided the 100x100 through the guts isn't going to work as it will get in the way of the hitch cable brake system and don't really want to go electric brakes.

So i'm thinking i'll cut the existing one off and start again.

50x100x4mm with some flat bar or angle for gussets where possible and just try and replicate where it was tied in to the chassis before.

It seems there isn't a whole lot of areas to weld an a-frame to the chassis as it only crosses such a small section.

Any other tips?

Where it all joins at the front, seems they put a thick arse plate over the top and bolt the hitch to that?

[TurboRA28]

My easter break...