SCRUBBY`S BOAT LOADER.

Thursday, Sep 27, 2012 at 21:32

Member - Scrubby (VIC)

SCRUBBY`S BOAT LOADER

The need for a boat loader of some kind became necessary if I wished to take the boat on any caravanning trip.
I searched the web and found several commercially manufactured versions but they were all rather expensive and most increased the height of the boat above the vehicle roof considerably.
I decided to have a go at designing and making my own.
Many, many, sketches and hours later I had a design that I reckoned would work.

I had seen a boat loaded by using a hand winch fitted to the bull-bar of a vehicle and after the boat was lent against the rear of the pack-rack the winch rope was attached over the vehicle roof to the bow, and the boat pulled up using the hand winch.
The problem with this system is the amount of force required to overcome the mechanical disadvantage of having only a small percentage of the boat’s length and weight above the rear of the p/rack. A lot of force is applied to the p/rack, its fittings and the roof of the vehicle.
Another problem was because the bow of the boat dropped down into the pack-rack as it was pulled on, a piece of dowel (broom handle) was required to be placed across the p/rack to keep the bow up.

I have a winch that is fitted with synthetic rope so I set about designing a “harness” that would fit to the boat and by attaching this to the winch rope it would firstly LIFT the boat to the point of balance on the rear of the p/rack and then pull it into position on the p/rack thus greatly reducing the force to the p/rack.
The only manual lifting required is to lift the rear corners of the boat about 200mm to attach the sling ropes.
THE BOAT CAN THEN BE LOADED WITHOUT THE NEED TO TOUCH IT.

THE VEHICLE

To protect the synthetic rope and reduce friction, I added some pieces of poly pipe to the b/bar and the p/rack where the rope will slide; I also made an aluminium guide and fitted it to the rear of the p/rack to prevent the lifting/pulling rope slipping sideways. When the angle of the winch rope goes above horizontal the rope can lift out of the guide.

Synthetic rope and poly pipe. Some electrical tape on the rope marks the amount of rope required to be unspooled when unloading the boat. (More detailed info later)



Poly pipe along the top of bull-bar.


Poly pipe along the front of pack-rack.



The poly pipe and winch rope guide on the rear of the pack-rack. See how the sling ropes are just slipped over the corners of the rack.

The idea is to spool out enough rope from the winch to go back up over the b/bar, the front and then the rear of the p/rack and down out about 2 metres past the rear of the vehicle.
I then made aluminium cross bar that fitted across the rear of the vehicle which fitted into the tow hitch; this bar had a swing out section each end that rested against the rear bumper to hold it straight. Wing nuts tightened underneath to hold them tight.
(In hindsight I would use two rails resting on the p/rack from the ground in place of the cross bar, two rails are much cheaper and easier to make and fit, also less bulk and weight to carry.)



The cross bar attached to the “AT 35” hitch with the swing out arms against the rear bumper.


THE BOAT

At the top corners of the Transom I fitted stainless steel eyebolts, one each side on the inside and one each side on the outside. (Total of four)






Stainless eyebolts fitted to the transom, same each side.









On the inside of the gunwale about a metre from the bow I fitted a stainless steel “D” bracket on each side of the boat. (Total of two)

THE ROPES

Not counting the winch rope there are three ropes that make up the “Harness”.
There are two ropes (sling ropes) of the same length that have an eye spliced into each end.
One end of each attaches to the top rear corners of the p/rack, the other ends attach to the outside eyebolts on the rear corners of the boat. (Use small shackles or some Carabiner type clip hooks) The length of these ropes should be so that when the boat is attached, the keel at the transom should be off the ground sufficient so that when the bow of the boat is lifted the keel clears the ground.



The pair of “sling” ropes.




The cross bar prevents the boat hitting the hitch or bumper.


The sling ropes prevent the boat keel scraping the ground.


The other rope is the “lift” or “pull” rope, this has an eye spliced in each end and another eye exactly in the middle. (I found that it was easiest to splice the middle eye first as the end eyes are easier to alter for adjustment of length)
This pull rope is approximately 11 metres long. (Some adjustment of length may be required later)


The ends of pull rope are threaded through the “D” fittings and then attached to the eyebolts on the inside of the transom.



The ends of the pull rope are threaded down through the “D” fittings.


The middle eye of the pull rope is attached to the end of the winch rope.
** Either remove the hook etc from the winch rope or heavily wrap it in a lot of rag or similar to prevent windscreen or vehicle damage should you let the winch rope go slack. I remove all but the thimble.

THE PICTURES NOW TELL THE STORY



Ready to be pulled by the winch.





The winch rope about to clear the guide.



The boat is totally clear of the ground and the winch rope is well clear of the guide.


About to rest against the rack.



As the boat overbalances onto the rack and the winch rope slackens.


The point of balance.


The bow of the boat remains slightly elevated until it is over the front of the pack-rack.


The bow touches down at this position.


The handles on each side of the foredeck are angled at the front to assist in pulling the boat up and over the front rail of the rack.


When the boat is against the two vertical stops on the front of the rack it is positioned correctly. Being sure that the rear window will lift fully open without hitting the boat.

That’s it, now remove the winch rope, the sling ropes and the cross bar. The pull rope can remain fitted, just tie it back to the p/rack, it will be required when unloading the boat.


The cross-bar lays in the p/rack; the ropes take very little room.
** Note the extra rope (blue & yellow), prior to unloading the boat one end of this rope is tied to the bow and the other taken out behind the vehicle.


UNLOADING

To unload the boat it is very much the opposite of the loading procedure except for a couple of things.

The sling ropes are fitted the same as when loading.

Enough winch rope is unspooled to attach to the pull rope plus just sufficient extra that will allow it to take the load when the boat is pulled backwards until just past the point of balance. After establishing the amount of winch rope to unspool I wrapped some electrical tape around it near the winch to mark the amount required each time.
(See first picture)

Another length of rope (blue and yellow in previous pic) is tied to somewhere on the bow. (I use one of the handles.) This rope is then taken over the roof and out behind the vehicle and used to pull the boat off the r/rack until just past the point of balance, at the same time the winch rope should become tight and hold the weight of the boat.




The point of balance. When unloading, lower the boat with the winch until it rests against the cross bar and then let out more rope to allow the boat to be pulled “overbalance” (see picture below)



Let enough slack in the w/rope to allow the boat to be pulled over balance.

Gently let out a little more winch rope so that as the boat slowly slides along the r/rack it lowers itself onto the sling ropes, they are now taking the weight and the boat is still resting on the r/rack. Let out some more winch rope so that when the Blue and yellow rope is pulled the boat will gently “overbalance” and then lowered by the winch until the boat is on the ground.
[ I have no photos showing the “Blue & Yellow” rope fitted. If it were fitted it would show it tied to the Bow at the top/centre of photo and hanging out behind the boat to about bottom right of photo.]


It is just a matter of undoing the ropes.
Removing the cross bar.
Winding up the winch rope.
Stowing it all away.

Of course if you don’t need to use the vehicle before you load the boat again.
Just hook the sling ropes up.
Wind in the winch rope and remove the control.
Now launch the boat, grab all the gear and ……… bloody hell I’ve got a fish already.


COST

If you have a vehicle already fitted with a pack-rack, bull-bar and a winch loaded with synthetic rope.
Then the cost is LESS THAN $100.00

N.B.

Because your boat and your pack-rack are probably different to mine the length of the harness ropes and the positioning of the “D” brackets may mean a bit of trial and error to begin with. The position of these D`s determines how the boat gently lowers itself onto the p/rack and also the LIFTING OF THE WEIGHT from the transom.

I clamped the D`s with small clamps until I got their correct position.
I only tied the loops in the harness ropes and only when I had the lengths correct did I splice them.
I used a piece of timber for a trial and error cross bar.

As I mentioned earlier it would be perhaps a better idea to use a pair of rails that rested on the ground and lent against the p/rack at a suitable angle instead of the cross bar.
Again a bit of trial and error might be required.







27 June 2011 9am
Ready to go, Cape York here we come.

I don`t know where i`m going but i`m enjoying the journey.
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