Thread: Drop axle on caravan

Originally Posted by bacicat

All painted and looking pretty.

Can I ask, why isnt there a plate under the draw bar (below the hitch)? I would have thought this would be a big flex point and you would need a base plate.

dont mention the war!

Originally Posted by Cap

Can I ask, why isnt there a plate under the draw bar (below the hitch)? I would have thought this would be a big flex point and you would need a base plate.

Good question Carlos, and yes it was thought of, but not deemed nessesary in the end. There will be very little flex there. Points to remember - this is an on road van only - not going on the dirt or off road. The drawbar now has 200% more steel in than factory. The original never had a plate underneat and survived 2 decades of being towed before being parked up. The spare wheel support half way up the bar also prevents twisting. The baseplate the coupling is bolted to is 10mm thick - the factory plate was 4mm. The 10mm plate is welded underneath as well. As it sits, it is heaps stronger than it ever was - even from the factory when new. Over engineering just adds more weight which I don't want - the whole thing weighs under 1000Kg. The guy that welded it up did the engineering calculations and said we were at least 3 times over what was required for the steel used - which is 3mm mild steel - australian made, not the 2mm 'high tensile' chinese steel used in a lot of vans these days. I have no concerns about the long term strength of this bar.

Does that answer your question?

Originally Posted by Pedro_The_Swift

dont mention the war!

Don't worry mate, happy to have these conversations. The design was drawn up by me - it looked like a long triangle. It was developed into what you see by a combination of me, and Engineer and the fabricator that welded it up - I'm not about to second guess there ideas or calculations. They have both built much bigger and stronger things in the past. I think as DIY'ers we naturally tend to over engineer things because we don't fully understand the strengths and weaknesses. I certainly do - my back verandah is made from steel which I built myself. With the foundations I used and the steel I used, a builder who I know worked out I could put an upstairs room on top of it and still be legal...

Gav, I would also angle the end of the drawbar back and seal the ends about 2/3s of the way up from the bottom, this will stop scooping dirt into the drawbar.

Like this

Well, it's back home.

What a difference! It towed beautifully. Before it was quite twitchy at 85KPH on the highway, but now it's rock solid. Tested it up to 100 and it is fine. Backing off the throttle suddenly doesn't upset it, and treading on the brakes brings the whole show up straight. It tracks well, tows straight and doesn't crab at all.

One very happy chappy.

Will finish off a few bits and pieces early next week when I get a chance and should have it in for rego sometime mid week.

are they a Toyo HO8?

Originally Posted by Pedro_The_Swift

are they a Toyo HO8?

Um, not sure...

They are certainly a Toyo Light Truck tyre, so they could be...

I asked for a decent quality LT tyre and that's what they recommended. The tyre place I use has never steered me wrong, so I went with their advice. They have a load rating of 900Kg @ 65PSI which is quite good and way more than I will subject them to, so I hope they go the distance.

I'll check tonight.