A past post has helped decide that I need a winch fitted in my boat shed
.... to assist in pulling in of twin axle trailer.
Had a number of exchanges .. pointing me to caravan movers - but these
ended up in a'dead end'
The issue is there is a slight slope on drive before I get trailer into
boat shed ... and while I could do this on a single axle trailer - it is
impossible to do this on your own with the new twin axle trailer.

The issue is any steering that takes it off straight line, means one
axle tends to 'crab' over while one rolls ... huge effort when trying to
push manually, if I had winch taking care of the pull, all I would need
to do then is steer.

Boat & trailer is 2000Kg, but that is dead weight ... and I am not
trying to lift it ...

I have seen 3500Lb winch kits, which I'm hoping will be man enough for
the job .. http://tinyurl.com/c48jowx
Anybody any view if 3500LB is enough ? .... this is 1590kg .... and I'm
assuming this is far more pulling power than I have been able to exert
manually.

My thought would be use winch and then split the pull to each corner of
trailer with a rope & pulley, allowing me to easily steer from front of
trailer while pull applied by winch i.e :

http://tinyurl.com/dxkf6ev

If winch did struggle (doubt it) I could turn winch cable back on itself
with a snatch block and gain a 2:1 advantage.

I'd weld up a small stand out of 5mm steel, resin bolt that to concrete
floor, keeping winch pull level with trailer, and also up off any water.

Comments ?


I'll post a second Q related to battery size needed

On 16/12/2012 15:10, Rick Hughes wrote:

I have seen 3500Lb winch kits, which I'm hoping will be man enough for
the job .. http://tinyurl.com/c48jowx
Anybody any view if 3500LB is enough ? .... this is 1590kg .... and I'm
assuming this is far more pulling power than I have been able to exert
manually.

That's vast overkill - almost enough to lift it vertically, and you say
that your drive is on a slight incline. I'm still not quite sure why you
don't just use a hand winch or block and tackle.

http://www.ebay.co.uk/itm/MANUAL-MAR...item1e709b571c

This costs £14.99.

Of course it may 20 mins to do something you can do in 5 with an
electric winch, but you save all the trouble with batteries.

On 16/12/2012 20:05, GB wrote:
I'm still not quite sure why you don't just use a hand winch or block
and tackle.

Nor me. And it's a boat. Don't you have any gear at all? fx strikes
forehead not even an anchor winch?

Andy

On 16/12/2012 22:00, Andy Champ wrote:
On 16/12/2012 20:05, GB wrote:
I'm still not quite sure why you don't just use a hand winch or block
and tackle.

Nor me. And it's a boat. Don't you have any gear at all? fx strikes
forehead not even an anchor winch?

Andy


Nope ... anchor is on a rope, but no winch (it's a ski boat)

On 17/12/2012 19:09, Rick Hughes wrote:
Nope ... anchor is on a rope, but no winch (it's a ski boat)

That's not a boat :P

More seriously, how about two tackles, one to each side?

Andy

On Sun, 16 Dec 2012 20:05:06 +0000, GB wrote:

That's vast overkill - almost enough to lift it vertically, and you say
that your drive is on a slight incline. I'm still not quite sure why
you don't just use a hand winch or block and tackle.

IIRC this is one man operation. If he's winding the whinch lever he's not
steering... And being a double axle trailer it'll be easyier to steer
when it's actually moving compared to stationary.

--
Cheers
Dave.

On 16/12/2012 22:29, Dave Liquorice wrote:
On Sun, 16 Dec 2012 20:05:06 +0000, GB wrote:

That's vast overkill - almost enough to lift it vertically, and you say
that your drive is on a slight incline. I'm still not quite sure why
you don't just use a hand winch or block and tackle.

IIRC this is one man operation. If he's winding the whinch lever he's not
steering... And being a double axle trailer it'll be easyier to steer
when it's actually moving compared to stationary.



exactly .... that is the key issue.

when there are 2 of us we can push in OK ... on my own I simply can't
get the sideways pressure & rearward force enough to move it ... the 2nd
axle acts almost as a brake as the tyres crab over .... inherent design
flaw in twin axle trailers.

One Caravan company got over this by having a hydraulic system that
retracted one axles set of wheels off the floor for 'manhandling'


What would be ideal, is if they had some form of rear steering
'floating/swivel' on the rear axle, that would cure the problem.


I do this to a certain degree by jacking up the front jockey wheel,
putting most of weight on raer axle, it makes it easier for 2 of you to
move ... but when you are on your own, because of angle of boat you push
against the raised bow, and it tends to lift bow up off rollers rather
than push trailer backwards.

That 2nd axle really does act like a brake ... for anything other than a
straight line.

On 16/12/2012 20:05, GB wrote:

I'm still not quite sure why you don't just use a hand winch or block and tackle.

http://www.ebay.co.uk/itm/MANUAL-MAR...item1e709b571c


I have a 2 tonne one of those winches fitted to my boat anyway ... it is
what pulls boat onto the trailer.
Unfortunately it's on front of trailer not on rear - so no use for
pulling trailer in ... plus boat is in the way.

The reason why I don't want to use a hand-winch or block & tackle is
easy .... it is very difficult to push up the slight slope and steer
....it takes a lot of effort to move the twin axle off anything other
than straight course.

Therefore trying to operate manual winch or block & tackle while trying
to apply a significant sideways effort on steering is just too hard.

A motorized winch running off remote control means I can press button
and apply sideways pressure to jockey wheel to steer, no need to apply
any rearwards pressure.


I looked at motorized caravan movers (~£900) and even those struggle
with twin axle trailers .
You can get bolt on axle motors, but 2 things no good here - one they
wouldn't last being dunked in sal****er ... and 2 they cost £2.5k

On Monday, December 17, 2012 7:09:07 PM UTC, Rick Hughes wrote:
On 16/12/2012 20:05, GB wrote:



I'm still not quite sure why you don't just use a hand winch or block and tackle.

Me, too, can't be arsed reading it all. Couple of pulley blocks with karabiners to hook onto either side, cleats to hold the rope and a length of 3x2 to alter direction. The arrangement served the navy for centuries running out guns of several tons. You can remove the rope and pulleys for use elsewhere when you're not pulling boats around.

On 17/12/2012 19:09, Rick Hughes wrote:

The reason why I don't want to use a hand-winch or block & tackle is
easy .... it is very difficult to push up the slight slope and steer
....it takes a lot of effort to move the twin axle off anything other
than straight course.

Thanks for explaining.




A motorized winch running off remote control means I can press button
and apply sideways pressure to jockey wheel to steer, no need to apply
any rearwards pressure.

I'm delighted that you are not going to be between the boat and the
electric winch. Elfin safety will approve of your not being so liable to
be run over.

The remote for the winch looks like it's IR, will the boat be in the
way? Apart from that minor problem, the winch you have chosen should be
vastly more than equal to the job.

Batteries are marketed as XX ah. So a 60 ah one (theoretically) can
supply 60 amps for 1 hour, or 120 amps for 30 mins, or 1 amp for 60 hours.

Your 1.2 hp winch will use about 75 amps when working flat out, but that
will be for less than 5 minutes, and most of that time it won't be flat
out. Just when starting, the winch will use more current.

In theory, then, a rather small battery should be sufficient. In
practice, you should get a fairly meaty car battery.

I see that Eurocarparts are doing a Bosch 43 ah battery for £36 and a
rather bigger one for £48. Cheap as chips! Given that, I wouldn't bother
messing around with dud batteries from breaker's yards.

What you might do is replace your car battery with a new one, and use
your working car battery for the winch. What's in your car?

On 16/12/2012 15:10, Rick Hughes wrote:
A past post has helped decide that I need a winch fitted in my boat shed
... to assist in pulling in of twin axle trailer.
Had a number of exchanges .. pointing me to caravan movers - but these
ended up in a'dead end'
The issue is there is a slight slope on drive before I get trailer into
boat shed ... and while I could do this on a single axle trailer - it is
impossible to do this on your own with the new twin axle trailer.

The issue is any steering that takes it off straight line, means one
axle tends to 'crab' over while one rolls ... huge effort when trying to
push manually, if I had winch taking care of the pull, all I would need
to do then is steer.

Boat & trailer is 2000Kg, but that is dead weight ... and I am not
trying to lift it ...

I have seen 3500Lb winch kits, which I'm hoping will be man enough for
the job .. http://tinyurl.com/c48jowx
Anybody any view if 3500LB is enough ? .... this is 1590kg .... and I'm
assuming this is far more pulling power than I have been able to exert
manually.

My thought would be use winch and then split the pull to each corner of
trailer with a rope & pulley, allowing me to easily steer from front of
trailer while pull applied by winch i.e :

http://tinyurl.com/dxkf6ev

If winch did struggle (doubt it) I could turn winch cable back on itself
with a snatch block and gain a 2:1 advantage.

I'd weld up a small stand out of 5mm steel, resin bolt that to concrete
floor, keeping winch pull level with trailer, and also up off any water.

Comments ?


I seem to recall - higher up the thread - telling you how to calculate
the pull required. Damned if I'm going to do it again!
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

On 16/12/2012 20:39, Roger Mills wrote:

I seem to recall - higher up the thread - telling you how to calculate
the pull required. Damned if I'm going to do it again!


2tonnes up 'a slight slope' won't be much until the tyres hit an
imperfection in the roadway, or a lip going into the boat house. Even
then, it won't be much. All this faffing around when a £15 hand winch
will be fine. Or at least start with that and upgrade later if needed.

On 16/12/2012 22:03, GB wrote:
On 16/12/2012 20:39, Roger Mills wrote:

I seem to recall - higher up the thread - telling you how to calculate
the pull required. Damned if I'm going to do it again!


2tonnes up 'a slight slope' won't be much until the tyres hit an
imperfection in the roadway, or a lip going into the boat house. Even
then, it won't be much. All this faffing around when a £15 hand winch
will be fine. Or at least start with that and upgrade later if needed.


I have explained why this is not an option.

On 16/12/2012 20:39, Roger Mills wrote:
floor, keeping winch pull level with trailer, and also up off any water.

Comments ?


I seem to recall - higher up the thread - telling you how to calculate
the pull required. Damned if I'm going to do it again!


You said to do it .... but didn't say how to achieve that ..........
I have no way I know of to calculate the pull ..that was my original Q.

I know the angle of the drive, weight of boat, trailer, length of pull
.... but have no idea of rolling resistance, or friction when one axle is
crabbing - so unable to calculate pull required.

On 17/12/2012 19:19, Rick Hughes wrote:
On 16/12/2012 20:39, Roger Mills wrote:

I seem to recall - higher up the thread - telling you how to calculate
the pull required. Damned if I'm going to do it again!


You said to do it .... but didn't say how to achieve that ..........
I have no way I know of to calculate the pull ..that was my original Q.

I know the angle of the drive, weight of boat, trailer, length of pull
... but have no idea of rolling resistance, or friction when one axle is
crabbing - so unable to calculate pull required.

What part of this didn't you understand?

Quote from earlier post

"To pull a trailer up a slope you need a horizontal(ish) force equal to
the rolling resistance plus the component of the trailer/boat weight
acting along the slope (weight multiplied by the sine of the angle which
the slope makes with the horizontal)

You measure the first of these by pulling the trailer along a horizontal
surface by means of a spring balance. You can calculate the second.

For example, if the all-up weight of the boat plus trailer is 2000Kg, I
would expect the rolling resistance to be around 25Kg. If you pull it up
a 5 degree slope (approx 1 in 12) the component of the weight along the
slope will be about 175Kg - i.e. 200Kg in all.

When the hoist is laid on its side, it should be able to exert a similar
horizontal pull to its rated vertical lift when used normally. So 250Kg
should be ok for a 5 degree slope. If it's steeper than that, you might
have a problem - so make your own measurements and do your own
calculations with the actual data."

\Quote

As I said, you'll need to measure rolling resistance by pulling it on a
level surface with a spring balance. But, from memory (going back 40+
years!) when doing performance calculations on motor vehicles with
radial tyres (cross-ply were higher) we used to use 13 lbs per 1000 lbs
of weight - hence my guess at 25 (26) Kg for a trailer weighing 2000 Kg.

Then you'll need to measure the angle which the slope makes with the
horizontal, and multiply the weight of the trailer by the sine of that
angle in order to calculate the component of the weight acting down the
slope and then add that to the rolling resistance to find the total pull
required.

The rolling resistance will be a bit higher if the tyres are scrubbing,
but you - not the winch - will be providing the side (steering) force.
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

On Tuesday, December 18, 2012 11:56:51 PM UTC, Roger Mills wrote:
On 17/12/2012 19:19, Rick Hughes wrote:
On 16/12/2012 20:39, Roger Mills wrote:

I seem to recall - higher up the thread - telling you how to calculate
the pull required. Damned if I'm going to do it again!

You said to do it .... but didn't say how to achieve that ..........
I have no way I know of to calculate the pull ..that was my original Q.

I know the angle of the drive, weight of boat, trailer, length of pull
... but have no idea of rolling resistance, or friction when one axle is
crabbing - so unable to calculate pull required.

What part of this didn't you understand?
Quote from earlier post
"To pull a trailer up a slope you need a horizontal(ish) force equal to
the rolling resistance plus the component of the trailer/boat weight
acting along the slope (weight multiplied by the sine of the angle which
the slope makes with the horizontal)
You measure the first of these by pulling the trailer along a horizontal
surface by means of a spring balance. You can calculate the second.
For example, if the all-up weight of the boat plus trailer is 2000Kg, I
would expect the rolling resistance to be around 25Kg. If you pull it up
a 5 degree slope (approx 1 in 12) the component of the weight along the
slope will be about 175Kg - i.e. 200Kg in all.
When the hoist is laid on its side, it should be able to exert a similar
horizontal pull to its rated vertical lift when used normally. So 250Kg
should be ok for a 5 degree slope. If it's steeper than that, you might
have a problem - so make your own measurements and do your own
calculations with the actual data."
\Quote
As I said, you'll need to measure rolling resistance by pulling it on a
level surface with a spring balance. But, from memory (going back 40+
years!) when doing performance calculations on motor vehicles with
radial tyres (cross-ply were higher) we used to use 13 lbs per 1000 lbs
of weight - hence my guess at 25 (26) Kg for a trailer weighing 2000 Kg.
Then you'll need to measure the angle which the slope makes with the
horizontal, and multiply the weight of the trailer by the sine of that
angle in order to calculate the component of the weight acting down the
slope and then add that to the rolling resistance to find the total pull
required.
The rolling resistance will be a bit higher if the tyres are scrubbing,
but you - not the winch - will be providing the side (steering) force.

Don't overlook the one gotcha in this. If there's even a quarter inch lip along the tow path, then for a short distance the winch is effectively pulling the load up a much steeper angle there.


NT

On 19/12/2012 10:09, wrote:


Don't overlook the one gotcha in this. If there's even a quarter inch lip along the tow path, then for a short distance the winch is effectively pulling the load up a much steeper angle there.


NT

Steeper, yes - but not *much* steeper because the tyres would even it
out. Also, if you'd got a bit of momentum going, you'd hardly notice a
small step.
--
Cheers,
Roger
____________
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checked.

On 18/12/2012 23:56, Roger Mills wrote:

Quote from earlier post

"To pull a trailer up a slope you need a horizontal(ish) force equal to
the rolling resistance plus the component of the trailer/boat weight
acting along the slope (weight multiplied by the sine of the angle which
the slope makes with the horizontal)

You measure the first of these by pulling the trailer along a horizontal
surface by means of a spring balance. You can calculate the second.

For example, if the all-up weight of the boat plus trailer is 2000Kg, I
would expect the rolling resistance to be around 25Kg. If you pull it up
a 5 degree slope (approx 1 in 12) the component of the weight along the
slope will be about 175Kg - i.e. 200Kg in all.

When the hoist is laid on its side, it should be able to exert a similar
horizontal pull to its rated vertical lift when used normally. So 250Kg
should be ok for a 5 degree slope. If it's steeper than that, you might
have a problem - so make your own measurements and do your own
calculations with the actual data."

\Quote

As I said, you'll need to measure rolling resistance by pulling it on a
level surface with a spring balance. But, from memory (going back 40+
years!) when doing performance calculations on motor vehicles with
radial tyres (cross-ply were higher) we used to use 13 lbs per 1000 lbs
of weight - hence my guess at 25 (26) Kg for a trailer weighing 2000 Kg.

Then you'll need to measure the angle which the slope makes with the
horizontal, and multiply the weight of the trailer by the sine of that
angle in order to calculate the component of the weight acting down the
slope and then add that to the rolling resistance to find the total pull
required.

The rolling resistance will be a bit higher if the tyres are scrubbing,
but you - not the winch - will be providing the side (steering) force.

Whilst the maths is impeccable, isn't this 200Kg figure somewhat
spuriously accurate? There's only got to be a rut in the drive, a pebble
in the way, or a lip into the garage for the required pull to go up
significantly. He'd probably want to double that figure.

In practice, he's getting a winch which is capable of far more, but it's
only £100, which seems incredibly cheap to me.

On 19/12/2012 12:20, GB wrote:
On 18/12/2012 23:56, Roger Mills wrote:

Quote from earlier post

"To pull a trailer up a slope you need a horizontal(ish) force equal to
the rolling resistance plus the component of the trailer/boat weight
acting along the slope (weight multiplied by the sine of the angle which
the slope makes with the horizontal)

You measure the first of these by pulling the trailer along a horizontal
surface by means of a spring balance. You can calculate the second.

For example, if the all-up weight of the boat plus trailer is 2000Kg, I
would expect the rolling resistance to be around 25Kg. If you pull it up
a 5 degree slope (approx 1 in 12) the component of the weight along the
slope will be about 175Kg - i.e. 200Kg in all.

When the hoist is laid on its side, it should be able to exert a similar
horizontal pull to its rated vertical lift when used normally. So 250Kg
should be ok for a 5 degree slope. If it's steeper than that, you might
have a problem - so make your own measurements and do your own
calculations with the actual data."

\Quote

As I said, you'll need to measure rolling resistance by pulling it on a
level surface with a spring balance. But, from memory (going back 40+
years!) when doing performance calculations on motor vehicles with
radial tyres (cross-ply were higher) we used to use 13 lbs per 1000 lbs
of weight - hence my guess at 25 (26) Kg for a trailer weighing 2000 Kg.

Then you'll need to measure the angle which the slope makes with the
horizontal, and multiply the weight of the trailer by the sine of that
angle in order to calculate the component of the weight acting down the
slope and then add that to the rolling resistance to find the total pull
required.

The rolling resistance will be a bit higher if the tyres are scrubbing,
but you - not the winch - will be providing the side (steering) force.

Whilst the maths is impeccable, isn't this 200Kg figure somewhat
spuriously accurate? There's only got to be a rut in the drive, a pebble
in the way, or a lip into the garage for the required pull to go up
significantly. He'd probably want to double that figure.

In practice, he's getting a winch which is capable of far more, but it's
only £100, which seems incredibly cheap to me.


There may well be other factors, but following my method of calculation
will at least give the right order of magnitude - and you can can add
whatever safety factor you choose. The OP claimed not to have a clue as
to where to start - so I sought to point him in the right direction, if
only to dispel any myth about the required pull being anything
approaching the dead weight of the trailer.
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

On 16/12/2012 15:10, Rick Hughes wrote:

Boat & trailer is 2000Kg, but that is dead weight ... and I am not
trying to lift it ...

Just wondering why the boat/trailer can't simply be reversed onto the
garage? Other than from a security perspective I suppose?

Pete@

--
http://www.GymRatZ.co.uk - Fitness+Gym Equipment.
http://www.bodysolid-gym-equipment.co.uk
http://www.trade-price-supplements.co.uk
http://www.water-rower.co.uk

On 16/12/2012 15:10, Rick Hughes wrote:
A past post has helped decide that I need a winch fitted in my boat shed
... to assist in pulling in of twin axle trailer.
Had a number of exchanges .. pointing me to caravan movers - but these
ended up in a'dead end'


Went ahead and made the stand - had it galvanized, resin bolted plate to
floor and grouted it in ..
Wired it up today ... and impressed with end result ...

http://tinyurl.com/cplfy94

The winch has a wired remote rocker switch, which may never get used
..... as it also has 2 wireless remote controls ....

It has 1500Lb pull capacity