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Red Witch Trailer calamity

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Created by RobRedWitch 1 month ago, 27 Nov 2020
RobRedWitch
5 posts
27 Nov 2020 8:18PM
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Hi brain trust !

I just purchased a 1976 Red Witch 20, but unfortunately have run into some dangerous troubles trying to launch her.
I have done a little reserch and am using the rope method to launch her, but every time I unhitch on the slant of a boat ramp (not a particularly steep one, hillarys boat ramp) she wants to flip over backward. It took the weight of me and the help of my partner (about 100kg total) to stop her from flipping over backward. This is even with the outboard motor stowed all the way forward in the cab.

My trailer ( very old and rusted so I am planning to rebuild / restore ) is such that the wheels sit in line with the keel, so here is my question;
Where should the trailer wheels be relative to the keel? Id imagine too far back and she would be stable but would be more hitch weight and would probably handle bad ?

Is the majority of the boats weight centred over the keel?

Any advice would be appreciated!

Thanks

SimonM
WA, 103 posts
27 Nov 2020 8:54PM
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We had a Space Sailor like this and had a really scary incident of it tipping back under rope method recovery. I added a couple of sockets on the trailer that I could install wheelie bars in that had about a 10inch wheel on the ends. Worked a treat. Set them a few inches off the ground on level. Just pop them in when U are rigged at the ramp or ready for recovery

shaggybaxter
QLD, 2228 posts
27 Nov 2020 11:49PM
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Select to expand quote
RobRedWitch said..
Hi brain trust !

I just purchased a 1976 Red Witch 20, but unfortunately have run into some dangerous troubles trying to launch her.
I have done a little reserch and am using the rope method to launch her, but every time I unhitch on the slant of a boat ramp (not a particularly steep one, hillarys boat ramp) she wants to flip over backward. It took the weight of me and the help of my partner (about 100kg total) to stop her from flipping over backward. This is even with the outboard motor stowed all the way forward in the cab.

My trailer ( very old and rusted so I am planning to rebuild / restore ) is such that the wheels sit in line with the keel, so here is my question;
Where should the trailer wheels be relative to the keel? Id imagine too far back and she would be stable but would be more hitch weight and would probably handle bad ?

Is the majority of the boats weight centred over the keel?

Any advice would be appreciated!

Thanks





G'day RobRed,
If you do alter position/centre of load you wouldn't want any more than 50kgs ball weight on your towbar. More than that and you've gone too far for sure .
cheers,
SB

Craig66
NSW, 2108 posts
28 Nov 2020 5:17AM
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I agree sb, it's all about ball weight. There are cheap scales to measure this. (I used old solid style bath room scales years ago)
Sounds like at the moment your trailer will be lifting the back of your car/Ute witch (pun intended) is very dangerous when towing.
IMO 50 kg is a tad light, but there are many factors, one being what your tow car is rated to, but not to much that winding up the jockey wheel and manoeuvring is hard work

Two options, simple fix if you have distance to move winch post forward on draw bar to place weight further forward and making sure all rollers still fully support boat.
Or move axel rear wards.
Removable wheels are great secondary system

RobRedWitch
5 posts
28 Nov 2020 6:24AM
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Craig66 said..
I agree sb, it's all about ball weight. There are cheap scales to measure this. (I used old solid style bath room scales years ago)
Sounds like at the moment your trailer will be lifting the back of your car/Ute witch (pun intended) is very dangerous when towing.
IMO 50 kg is a tad light, but there are many factors, one being what your tow car is rated to, but not to much that winding up the jockey wheel and manoeuvring is hard work

Two options, simple fix if you have distance to move winch post forward on draw bar to place weight further forward and making sure all rollers still fully support boat.
Or move axel rear wards.
Removable wheels are great secondary system


Yeah ok thanks for the insight.
I would say at the moment on flat ground my trailer has a ball weight of ~15 - 20kg
As ive got a Hilux I think ill go on the heavier size and when I make the new trailer put the wheels about a foot behind the centre of weight on the boat

RobRedWitch
5 posts
28 Nov 2020 6:24AM
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Any imput on where the centre of mass is on the Red Witch 20?

shaggybaxter
QLD, 2228 posts
28 Nov 2020 8:46AM
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Select to expand quote
RobRedWitch said..





Craig66 said..
I agree sb, it's all about ball weight. There are cheap scales to measure this. (I used old solid style bath room scales years ago)
Sounds like at the moment your trailer will be lifting the back of your car/Ute witch (pun intended) is very dangerous when towing.
IMO 50 kg is a tad light, but there are many factors, one being what your tow car is rated to, but not to much that winding up the jockey wheel and manoeuvring is hard work

Two options, simple fix if you have distance to move winch post forward on draw bar to place weight further forward and making sure all rollers still fully support boat.
Or move axel rear wards.
Removable wheels are great secondary system







Yeah ok thanks for the insight.
I would say at the moment on flat ground my trailer has a ball weight of ~15 - 20kg
As ive got a Hilux I think ill go on the heavier size and when I make the new trailer put the wheels about a foot behind the centre of weight on the boat






Too light a towball weight is more dangerous than too much, within limits. The biggest issue with too little weight on the tow ball is the trailer get's all squirrely when you are towing and can lead to the trailer driving the car.
In a past life I worked for the Hayman Reese aussie agents as well as manufacturing our own towbars and hitches, and we would often be required to inspect failures of towing hitches post accidents.
I used to have to hitch up crappy designs and drive them around the Mt Cotton testing facility. I was driving an XC ute once towing a tandem gravel trailer that had zero ball weight and it whipshawed the ute enough to toss the car off the track on the first corner.
Hilux are a good solid towing vehicle, but if you feel the car 'walking' left and right as you are driving along in a straight line, it's dangerous, get some weight on the ball, and quickly.
If you can't feel anything and you are still not sure, drive faster, the effect increases with higher speed.
Cheers,
SB

garymalmgren
631 posts
28 Nov 2020 7:05AM
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Hi Rob
There is a site called Trailersailorplace.www.trailersailerplace.com.au/
It is a friendly site with many knowledgeable sailors.
2 or 3 active Red Witch sailors on there too.
Watching someone launch successfully or talking to someone who does it all the time would be the way to go.
You may also end up with someone to pace or swap parts with.

Also a very good Red Witch rebuild thread on here. Worth contacting the writer.
www.seabreeze.com.au/forums/Sailing/General/Red-Witch-Build?page=1

ary

LooseChange
NSW, 2098 posts
28 Nov 2020 10:13AM
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Roughly speaking tow ball weight in Australia is generally accepted as being 6% and 15% of the total trailer mass or a more common definition is 10% of the allowable maximum tow capacity. This information is not a hard and fixed rule as vehicle manufacturers have different criteria for setting tow ball limits. There should be a sticker somewhere on your car that states max tow ball weight. As manufacturers reduce the weight of their vehicles in an effort to make the vehicle more fuel efficient they are then also commensurately reducing the ball weight limits.
If you move the axle too far back the trailer wheels will turn inside the path of the vehicle wheels in a turn.

shaggybaxter
QLD, 2228 posts
28 Nov 2020 9:47AM
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Select to expand quote
LooseChange said..
Roughly speaking tow ball weight in Australia is generally accepted as being 6% and 15% of the total trailer mass or a more common definition is 10% of the allowable maximum tow capacity. This information is not a hard and fixed rule as vehicle manufacturers have different criteria for setting tow ball limits. There should be a sticker somewhere on your car that states max tow ball weight. As manufacturers reduce the weight of their vehicles in an effort to make the vehicle more fuel efficient they are then also commensurately reducing the ball weight limits.
If you move the axle too far back the trailer wheels will turn inside the path of the vehicle wheels in a turn.



Thanks Loose,
I was being too simplistic, that's a more accurate and more general explanation of ball weight .
cheers,
SB

MEGAMAX
WA, 69 posts
28 Nov 2020 8:46AM
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I had a redwitch here in Mandurah. The thing would tip like that if I was in the cockpit but not on launch or recovery. There is something wrong if you can't hold it down. Is there water in the rear transom area? That used to fill when it rained....


Ilenart
164 posts
28 Nov 2020 12:41PM
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Megamax is showing the standard trailer for a Red Witch, which is normally fine for launching a Red Witch safely. I used to have a Red Witch which I launched every week at SOPYC and never had a problem with the boat tipping up. Sounds like a PO has made a modification either to your Red Witch or your trailer. I would go down to either Nedland Yacht Club or SOPYC and check out some of the Red Witches on the trailers and see where your Red Witch differs.

NB check out the Red Witch called "Escapade" at South Perth, that my old yacht. Someone has certainly spent time and money looking after the old girl :)

Ilenart

RobRedWitch
5 posts
28 Nov 2020 4:40PM
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MEGAMAX said..
I had a redwitch here in Mandurah. The thing would tip like that if I was in the cockpit but not on launch or recovery. There is something wrong if you can't hold it down. Is there water in the rear transom area? That used to fill when it rained....



Beautiful boat mate ! Love the paint job.

Thats a good point I should have checked for water.
What is your tow ball weight on that trailer ? (Roughly) Id guess that mine is around 10-15kg on flat ground so thats only ~2% (assuming 700kg tot). Id imagine that ill have to shift my keel a fair bit forward to achieve the appropriate 8 - 10% tow ball weight.

Anyone with a Red Witch 20 that launches on steeper ramps got imput for the tow ball weight they are running ?

All the feedbaxk is much appreciated cheers

Craig66
NSW, 2108 posts
28 Nov 2020 9:00PM
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Do you have a decent anchor and chain in the bow?
Might add 50kg

Woylie
WA, 9 posts
28 Nov 2020 7:28PM
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Ours definitely tips up, though we have a 20 kg motor on the transom that I suspect is most of the problem. We only tow between the hardstand and the ramp but getting in and out of the water requires one person on the prow or drawbar at all times.

After one close call I only put the rudder in when we are in the water, which is a total pain but easier than buying a new one.

shaggybaxter
QLD, 2228 posts
7 Dec 2020 5:36PM
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Great explanation from the Kiwis about weight distribution, apologies it is in Facebook mode.
fb.watch/2dBb5rS-Ns/



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"Red Witch Trailer calamity" started by RobRedWitch