RL24, RL28, and RL34 Trailable Yachts
from Rob Legg Yachts

RL Yacht Owner's Discussion Forum

Return to the Forum List

RL24 Trailer as per drawings
Hi guys

I've just searched this forum and it apppears that those who have tried the trailer design on this site are pleased with the design. Trouble is, the drawing is a bit fuzzy on some details. Does anyone know the section size and wall thickness of the recommended steel RHS? At one point it says 3x2 but at the top of the page it looks more like 5x2.


Matthew FRANCIS23-Aug-2007    Edit    Delete 
Re: RL24 Trailer as per drawings
The dimension of the RH section used on the origonal RL24 trailers was 3x2 (inches) I cannot remember the wall thickness we used, but it would have been around the middle of the range. The trailers did stand up for a long time. However since they were first built 35 years ago there have been many changes to the towing rules, and the rules within the states vary, so check that out before you start anything.
Rob23-Aug-2007    Edit    Delete 
Re: RL24 Trailer as per drawings
I too am looking at a new trailer, has anyone investigated the range of polymer trailers that are around.

How importantant is it to have a tilt trailer?

"Here's Luck" RL24
Towed by a STAVIC
Dixojo23-Aug-2007    Edit    Delete 
Re: RL24 Trailer as per drawings
The need to keep the frame rigid to avoid swaying at high speeds and flexing that can wear the hull on the rollers would lead me to using the 5X2 section for the frame and drawbar and 3X2 for the crossmambers.

A tilt trailer is essential for trailer sailers that need to roll off and be dragged on to the trailer.

I have a retrievemate and electic winch on the trailer which makes single handed launch and retrieves easy. I also have a long drawbar to give clearance for the stationwagon rear door.

A single axle about 1500kg capacity with ALKO meachanical override brakes is suitable for most RL24s with all their cruising gear.

A good site for the information and parts is http://www.alltrailerspares.com.au/

Australia has common rules in all States for trailers but I keep hearing stories of NSW wanting different features on their boat trailers to other states. If your building in NSW, it would be worth getting written advise from the rego people.
Greg24-Aug-2007    Edit    Delete 
Re: RL24 Trailer as per drawings
Plenty of second hand trailers out there and modify are one way. Adjustable tilt angle with a small chain is good especially with a good roller setup as it can be changed for steep or shallow ramps/beaches. All rollers are much-a-better that the old carpet covered rails which mean the trailer becomes a submarine each launch (read corrosion the main reason why most trailer brakes are useless within 3-6 months of the first submersion especially as there is less and less water to rinse them). A 12inch roller in the centre at the trailer rear saves paint/gelcoat. A handy Sampson post (ally or stainless vertical shaft) for controlled slipping of the bow line in tilt mode during launching no dropping the cable in the brime (read corrosion and I still have all my fingers). I never put the trailer in deeper than necessary. Submersion is corrosion (aim for just over the rims less than about 200mm I don’t let the brine touch the brake disks). Get some 3 or 4 second hand open mags so you can rinse the brakes easily old styles cheep but racy. Go for a single axle and save weight (>180kg per axle setup) saves on carbon /fuel. Load the weight in the tow vehicle not in the boat as an RL24 in cruise mode can go close or over the Max wheel bearing load capacity for single axle. Street legal tread trade-in light truck or Ute tyres are cheep even more applicable if you only have to go a short distance to the ramp at about $20 each. If you do make the trailer it is still an expensive item so do it right. Check out the requirements for Aust design certification. The local trailer builder /repair shop had to stamp and issue at a cost my plate here in Qld to meet Rego/insurance requirements. You will not want to face the bill if the insurance rejected your claim (because the trailer was not in specs) for that BMW you just side swiped .. >>>>Design and build so it can be hot dipped galvanise at the local gal plant (old repaired trailers can be treated too). Having a good trailer is as important as an O/B motor that doesn’t cut out when the first mate turns it down to idle and you are up the bow bouncing up and down in the wind sorting the anchor chain and she can't start it (oyster bed ahoy). There is no skeg on an RL24 to track in a roller >>If you do go for rollers remember when winching in if you want the boat to move across to the right you have to have the stern to the right and she will crab sideways into the centre and visa versa for moving the boat left. Cheers A! From the Dream On dt crew we've been there done that!
Garry Carr26-Aug-2007    Edit    Delete 
Re: RL24 Trailer as per drawings

I suggest you put a search through google using the name Marshall Engineering. When you get into their web site click on Useful Links and then on the National Code of Practice for building small trailers in Australia (version 4 published in June 1999). This code covers the construction and towing requirements for road trailers of less than 4.5 tonne aggregate trailer mass (weight of trailer and boat together). I think if you keep the combined weight of boat and trailer below 2 tonnes you are allowed to save a few bob by getting away with just override brakes

After you have studied the above ‘mighty’ document you should then contact your State Road Authority or your State Trailer Yachting Association to find out what exemptions and amendments have been declared in your State to the National Standard code. Apparently the above code was a defective piece of Legislation when it was introduced as it did not have a grandfather clause to cover trailers already in service. Overnight all RL24s, rowing eights and glider trailers were made illegal because of their rear overhang and some of them through lack of proper brakes. To place a RL 24 properly on single axle trailer with the correct tow bar loading means that the overhang will be over the declared 3.7 metres (distance from axle to transom).

25 Years ago I had sway problems with my RL24 when I went over 80 klm/hr. I found out it was caused by the air flow sweeping over the top of my HQ Holden and hitting the vee of the bows of the boat. This apparently was creating a lift to the front of the trailer and causing the whole unit to be tail happy and sway. I contemplated fitting a Formulae 1 type rear wing to the mast support to create a down force greater than the up force. My trailer was made with adjustable axle position holes so I shifted the axle as far back as it could go. This of course loaded up the back of the car excessively so I had to fit heavy duty air lift type shock absorbers to the rear wheels of the car and this solved the problem. It allowed me to then do the max speed of 100 Klm/hr.

Many of the States including Victoria have amended and exempted various parts of the code or the Australian Design Rules (ADR’s) as they are called now. Even after I shifted the axle back, I am still outside the 3.7 metres but as the Victorian Authorities have passed an amendment increasing this distance to 5 metres,I am in the clear. This is conditional on the transom not being wider than 2 metres and the mast having a red flag at its most after point.

Be careful when checking out all the above out because most of the States have passed different amendments and exemptions to ADRs and the 1998 National Towing Regulations. What really stands out now with all these new regulations is that it is a major crime to exceed the maximum towing load as recommended by the towing vehicle manufacturer. It could invalidate your towing vehicle warranty and even worse, nullify your insurance in an accident!

I agree with Garry when you build your new trailer put plenty of good rollers on and only put the tyres in the water and never the brakes or the wheel bearings. The RL24 has a good bow shape, is long and with a tilt trailer, this is possible. You then rely on an electric winch to do all the hard work of pulling the boat out of the water on the rollers. Never sink the trailer to float her on to reduce the winching effort!

It is quite apparent that the so called National Towing Regulations are a wee bit of a Federal/State disaster area and that the system is not working! I must tell you the story about a local wooden boat building company here in Paynesville who had the job of cutting a few of these beautiful lightweight wooden laminated rowing eights in half so that they could be towed on public roads in Victoria. They fitted two wooden bulkheads in the middle of the eight and the two halves were then bolted together with wing nuts! This was of course before Victoria passed an amendment to the overhang rule!!!

Alastair Russell1-Sep-2007    Edit    Delete 
Re: RL24 Trailer as per drawings
After trailing 24s and 28s over many thousands of Kilometers, and as far afield as Melbourne and Darwin, one of the most important things we found with adjustable undercarages on trailers was that the distance fron the centre of the wheel to the trailer ball be EXACTLY the same on each side, otherwise at high speeds awaying will occur.
Rob.2-Sep-2007    Edit    Delete 
Re: RL24 Trailer as per drawings

The first adjustable axle/spring arrangement I had was hopeless. It had these horrible torsion rubber suspension units and to adjust the fore and aft position of the axle I was restricted to a series of drilled holes. There was also not enough room between the hull of the boat, the mudguard and the tyre tread to enable me to fit 9 ply light truck tyres!

Before I came down here I fitted a new suspension arrangement comprising of leaf springs, axle, hubs and bearings along with new truck tyres to my trailer. I attached the sub assembly to the trailer using those special trailer U bolts and I was careful to align the axle up as you have recommended.

When I fronted the Vic Roads to transfer my NSW trailer registration, they demanded to see my trailer for an inspection! I went home and read the handout sheet on their trailer rules and decided not to go back! For about 4 years the boat on the trailer was registered in Vic and the trailer was registered in NSW in my name using my mate’s home address!

I just cannot win, as my old mark 1 RL 24 does not meet the latest version of the Victorian rl 24 class rules for a swing keeler and the trailer it sits on cannot be registered in Vic. without major money being spent on it.

What I did notice though, was when I stopped registering the trailer in NSW the bickering between the boat and the trailer stopped immediately. The boat is still pursuing with its log of claims and demanding that she be set free from her trailer and be placed on a mooring! She says that she wants to be a real boat with a proper keel and rudder! I am sure she is aware that I have a spare flying fifteen keel and rudder in the workshop!
Alastair3-Sep-2007    Edit    Delete 

Return to the Forum List       Add a message to this discussion