Need engineering ideas - launch for a boat

[migrant]

I know there are many engineering oriented people here and I need ideas.

Issue

I would like to get a boat
Need ideas on making a way to launch, and receive, the boat without encroaching (too much) on public beach area. Also reasonable priced (A helicopter is not in the budget)

Background

We live on the ocean in Bang Saphan
There are no marinas within a reasonable distance
There are also no boat launch areas

Details

Low tide, low season, which is now, the boat will need to travel about 20-30 meters over sand.
It needs to go up a couple rises, steepest is ~ 30-35 degrees
Total rise is about 4-5 meters
There is a very distinct difference between high, and low, tide and the different seasons, the info above is during lowest season
Only the last 5 meters is my land, the rest is public beach (as all are).
The boat weighs 700-800 kilos

My idea

There is a large tree, sufficient for the task at the high point on my land. I thought, pour a concrete pad at the base of the tree sufficient to the boat size.
Get a winch, with remote control (Lazada has) and attach high enough in the tree to provide sufficient lift.

But, questions

If the boat is 700-800 kilos, any suggestions on winch size (I can go real overkill, but can be costly)?
I guess I would put the boat trailer attached to the winch and raise, and lower, both.

Looking for other ideas, suggestions, beware of........

Thanks as always

Oh, rides will be offered when in Bang Saphan

[RCer]

Easy fix

[Big Boy]

They've got one like that on Palace guard patrol.

[Big Boy]

migrant, I'm definitely no engineer , but they have a set up similar to that in Hua Hin - minus the tree and remote. If you go down Soi 75, turn right and its about 250 yards along the beach. It might be worth discussing with them when you're up this way next.

[Nereus]

How soft / deep is the sand? A 700 / 800 Kg boat would need some very large tyres(or tires ) to stop it sinking into the sand. Is the slope steep enough to allow the boat / trailer to roll across the beach when launching? You may find that you need some portable rollers mounted on wide planks laid down on the sand to support the load, or some form of light matting. Fibreglass portable mats used to recover bogged 4WD vehicles are available, but they are not cheap. If only a short distance just use a couple of sets and move them a couple of times.

For a winch have you looked at mounting one on your truck? Or you could also mount one on a trailer type receiver bracket, either front or back bumper. Be a bit wary about winches from Lazada, some of them tend to be more of a toy. A good 8000 or 9000 lb pull 4WD winch runs around 35,000 Baht. They also can be had with a wireless control. There are smaller ones, but you get what you pay for. Also, watch out for the actual rope. Wire is the usual type, but does not go well with salt water. Synthetic ropes are much better and do not chop your head off if they break!

[T.I.G.R.]

Get one of those boats with the big propeller they use in the Florida Keys.

[PeteC]

Get one of those boats with the big propeller they use in the Florida Keys.

One of these?

Air_boat.jpg (33.12 KiB) Viewed 1888 times

[hin]

700 - 800 kg is not a very large boat. With engine, fuel, & other gear aboard, our 5 meter boat, built by the man alongside the highway in Thap Sekae is more than 700 kg, not including the trailer.

As you are only talking beach launching a light weight 4 wheel carriage would be more efficient and practical than a boat trailer. Can be easily made with 4 aluminum motorcycle or scooter wheels. Take out the ball bearings, press in hardwood roundstock and bore out to create hardwood bushings which will last almost forever in sand and salt water. Heavy wall plastic pipe, epoxied in, would be 2nd best. If you want bigger tires, but they will be heavier, get some old aluminum front car wheels including hubs, take out the bearings, drive in hardwood plugs & bore out to create bushings. A generous dose of lanolin on the wheel studs and lug nuts will render them easy to spin off even after 5 years in salt water. Lanolin = wool fat if you are an Ozie.

Bogging down is not a problem for a wheel rolling over wet or dry sand unless it is narrow, like a bicycle wheel. It is traction wheels that bog down, like with a car or motorbike - the wheels that are pushing will bog down in sand - not the ones that are free wheeling.

With a 30 - 35 degree slope, even with a few bumps and holes you will probably never need a winch pull of more than ½ the weight of the boat. A winch with capacity to lift the boat strait up could almost be considered overkill.

Wire rope will not “chop your head off” because it has no elasticity and of course you would use stainless. Nylon is the worst for elasticity but in pulling a boat you will never be able to put that much strain on it. In sand and salt water stainless wire rope will probably outlast the winch it is wound on. 400 series stainless is best for wire rope that flexes because altho it will go brown it will not work harden like the 300 series stainless that stays shiny.

A deadman outside the surf line will make easiest launching thru the surf and a mushroom anchor is most practical for that. Best if you can leave it there. If you put a strain on it it will bury itself and not be a bother to anyone. Easily made by welding a large eye or shackle onto an old pickup axle and the wheel rim bolted onto it as normal. Polypropylene line is nice because it floats and is easy on the hands. Yellow is easiest to see. Make it plenty long, extending from mushroom anchor and just pull your boat out hand over hand thru the surf, taking a wrap around your bow cleat before each wave hits.

Launching or retrieving a bouncing boat onto a boat trailer is not fun. Easier to strap your boat securely onto its beach cart then drop the cart after in deep enuf water that the boat will be floating free of it. Have 2 polypropylene lines attached to the cart - at center balance point each side - and pull the cart into deep water outside the surf line when returning so you can pull it up under the boat while still in deep enuf water that your boat will not be bouncing up and sown on top of it in shallow water. The mushroom anchor outside the surf line can make life a lot easier in many ways. Needless to say, your cart needs to be light but heavy enough that flotation of the tires will not prevent it from sinking. If everything is arranged properly you can launch and retrieve your boat even thru small surf while almost not getting wet. And don’t get your propeller tangled. Much easier to explain and draw the finer points and details than to squeeze it all into a blog.

[pharvey]

Rocket propellant?

Seriously, I'm with Nereus (HHF's Mine of Information) on this one. Weight certainly an issue - or get a "Duck" ! (https://www.getyourguide.co.uk/london-l ... urs-t5615/)

If coming onto a beach with "soft sand", why not use something simple like an oversized length of (strong) metal conduit that would spread the load?

Or speak to barrys - the resident boat expert?

[Terry]

Rocket propellant? ......

Down boy

[Nereus]

Each to his own, and the OP was asking for suggestions!

Wire rope will not “chop your head off”

And I would not be surprised if you are one of those people that drape a steel tow rope over the ball of a trailer hitch, and then wonder why it broke when you pull a bogged car with it and whips back through the rear window of the tow vehicle. You obviously do not know what Dyneema rope is, or just how much a steel cable will whip if it parts under load! And stainless cable will whip just the same if it, or any part it is attached to parts.

A deadman outside the surf line will make easiest launching thru the surf and a mushroom anchor is most practical for that. Best if you can leave it there.

Sure, dump some more rubbish in the ocean, and never mind if somebody else gets either themselves, or their boat damaged! Just as leaving some Polypropylene line floating for somebody else to get around their prop!

The OPs question was more concerned about pulling his boat up an incline and across the beach. To save all the hassle, if it was me in that position, I think that I would buy an old farm tractor. What ever trailer you use will not be a problem, and will only be on the beach for 5 minutes or so. Besides, that is probably the way the Thais would do it and it will never raise an eyebrow! Happy boating.

[Big Boy]

I think that I would buy an old farm tractor. What ever trailer you use will not be a problem, and will only be on the beach for 5 minutes or so. Besides, that is probably the way the Thais would do it and it will never raise an eyebrow! Happy boating.

As I've already said, my brain could not be further removed from being an engineer. However, I've seen the mess buying an old farm tractor can leave when used for this purpose. That was the solution used just along from Soi 75 before they installed the winch. If the conditions were wrong, it would turn parts of the beach into quicksand. My eldest granddaughter lost a pair of shoes to the carnage left behind, and we almost lost our smallest dog to it. The shoes were never recovered. Fortunately, we were able to save the dog.

The old tractor used to leave puddles of oil, and often needed a team of bodies working with it. Hooking up to the winch is so much easier, and walking past that point is once again safe.

[migrant]

Hi Guys,

Nereus I never answered, sorry, the sand is fairly firm so a set of oversized tires would probably work well. The winch I can attach to a large tree that is situated well. I never saw mats like you describe, but when we lived in northern climates we used wire netting for tires stuck in snow

Thanks

[Nereus]

The following are what I was referring to. Wire mesh would work, but it tends to sink in a lot depending on the weight of course, and just curl up.

http://www.ebay.com.au/bhp/4wd-sand-recovery-tracks

[kendo]

Maybe consider a quad bike with a town hitch. I used to have a road legal one the tyres only ran at four psi so you would get plenty enough traction. You could also use it for other leasure purposes. Do you really want to concrete a pad on your beach front.