Thread Tools Search this Thread
Old 01 May 2006, 04:42   #11
Trade member
Cookee's Avatar
Country: UK - England
Town: Salcombe, Devon, UK
Boat name: BananaShark
Make: BananaShark
Length: 10m +
Engine: 2xYanmar 260 diesels
Join Date: Mar 2003
Posts: 4,225
Our A frame is designed for wakeboarding, we were pulling up 2 monoskiers last summer without any problem - I'll give you a tow at Ribex if you like Roy!
Originally Posted by Zippy
When a boat looks that good who needs tubes!!!
Cookee is offline   Reply With Quote
Old 01 May 2006, 10:37   #12
Country: UK - England
Town: Torbay
Boat name: Loupy Lou
Make: Yamaha 480R
Length: 4m +
Engine: 50HP
Join Date: Mar 2006
Posts: 147
Folding Frames

I am looking to keep my new rib in my double garage but I am limited by height So I'll either need an A frame that is low, removable (easily) or a folding pole that I can fold down for storage. Any ideas? Also if you know the height of the top of your A frame when the RIB is on the trailer that could help in my plans. Cheers

Scrumdown is offline   Reply With Quote
Old 01 May 2006, 13:02   #13
GED's Avatar
Country: UK - Wales
Boat name: The Full Morty II
Make: Air Craft/Shakespere
Length: 8m +
Engine: Etec 300hp/Etec150hp
Join Date: Feb 2001
Posts: 603
a frames

Not all A frames are the same
Attached Thumbnails
Click image for larger version

Name:	DSC00214 (Small).JPG
Views:	214
Size:	49.5 KB
ID:	18776  
GED is offline   Reply With Quote
Old 01 May 2006, 13:58   #14
Country: UK - England
Town: Hoxne
Boat name: Southern Comfort
Make: NorthCraft 5.5
Length: 5m +
Engine: 150 Optimax
MMSI: 235033276
Join Date: Nov 2005
Posts: 122
Send a message via MSN to Under the Thumb

If you use a high rope position to wakeboard or monoski , do you need to put extra weight in the bow to keep the nose down?
Northern Exposure Rescue

Marine Safety / Photography / Event Management
Under the Thumb is offline   Reply With Quote
Old 01 May 2006, 14:08   #15
Country: UK - England
Town: Newquay, Cornwall.
Boat name: None :(
Make: None :(
Length: 5m +
Engine: None :(
MMSI: None :(
Join Date: Jun 2005
Posts: 1,280
I dont seem to need any
roycruse is offline   Reply With Quote
Old 01 May 2006, 14:13   #16
Now back to being Mollers!
Country: UK - England
Town: Arundel
Boat name: Mike Bravo 1
Make: Scorp
Length: 9m +
Engine: Yanmar 300
Join Date: Oct 2005
Posts: 652
Originally Posted by Under the Thumb
If you use a high rope position to wakeboard or monoski , do you need to put extra weight in the bow to keep the nose down?
Eh?! Not heard of that one before. If the bow did rise surely a dab of the trim switch would cure it?
Alice is offline   Reply With Quote
Old 01 May 2006, 19:06   #17
Country: UK - Wales
Town: Southampton
Boat name: DynaMoHumm/ SRV/deja
Make: Avon8.4, 5.4 & 4.777
Length: 8m +
Engine: Cat3126 Yam 90 &70
MMSI: 42
Join Date: Dec 2003
Posts: 6,533
Originally Posted by Tim M
I have double A frames on two of my RIBs. Would not hessitate about towing off either of them. In answer to your question they are bolted through the transom, and through the deck.

I should hope the a frame is bolted through the transom and the deck, however what are they bolted to under the deck, a threaded insert or an under deck plate?
Here it comes again, I don't stand a chance
Soul possession, Got me in a trance
Pullin' me back to you - Deja Voodoo
Rogue Wave is offline   Reply With Quote
Old 04 May 2006, 03:39   #18
havener's Avatar
Country: UK - England
Town: Far west!
Boat name: Vigilant
Make: Humber
Length: 6m +
Engine: 90hp
Join Date: Feb 2006
Posts: 505
This could be controversial....

NEVER EVER tow from an A frame unless you have the manufacturer's certification to do that - and I mean from the hull manufacturer as well as as the frame builder.

By all means run a rope over or through the frame for towing, preferably using a bar to keep the rope out of the prop's way.

The end of the tow line, however, should be attached to a purpose built towing cleat on the deck, or even better tow via a bridle. This provides a number of advantages, and is good practice even if your frame is rated for towing -

1. By passing the rope over the frame, it puts the frame in compression rather than the tow line acting against the frame's joints and strength.

2. If you need to jetison the tow rapidly in an emergency, the helmsman or crew can cut the rope by the cleat (ensuring no-one is in it's recoil line) a lot quicker than you could if you had to climb onto the frame first.

havener is offline   Reply With Quote
Old 04 May 2006, 07:30   #19
Country: UK - Wales
Town: Barmouth
Boat name: Blue Marlin
Make: Ribcraft
Length: 7m +
Engine: Yanmar 315/Bravo 2X
MMSI: 235020218
Join Date: Jun 2003
Posts: 826
A couple of summers ago we were in Cyprus, and they were towing 6/8 man bananas from the A-Frame of a 6.5m RIB (Humber?). They had mounted it at the top of the A-Frame to make sure that the tow line stayed clear of the prop, but they had then run additional lines from the top of the A-Frame to the cleat at the bow of the RIB to support the A-Frame (the only people on the RIB were the crew - no passengers usually).

When stationary the lines weren't hanging loose, but were 'tight' like a guy rope of a tent (i.e. you could move them up and down a bit). Once under way and towing, the lines were rigid - and I was uncomfortable sitting anywhere near them!!

ANYWAY - my point - the forces applied to the top of the A-Frame are very big - hence the movement in the A-Frame and tightening of the ropes that were supporting it. I'd rather use the towing eyes than just tie to my A-Frame - unless the A-Frame is designed for it.

My towing bridle is just a piece of 3-strand nylon line spliced onto carabiners - but I've put some bungee cord through the 3-strand and clip that onto the A-Frame - when not under load the bungee pulls the rope up and away from the leg - and when under load, the bungee is stretchy enough that it lets all the load go to the towing eyes and not up to the A-Frame. I've not used it that much, but when I do, I haven't managed to foul my prop (yet ).

DGR is offline   Reply With Quote
Old 04 May 2006, 11:03   #20
Country: Other
Town: Stanley, Falkland Is
Boat name: Seawolf
Make: Osprey Vipermax 5.8
Length: 5m +
Engine: Etec 150
Join Date: Mar 2006
Posts: 3,655
It's a simple matter of geometry - if you are towing off the top of the A frame the twisting force on the transom will be huge compared to if you are towing off the A frame just above the transom, for example.

I wouldn't even think of it on mine, it would break off immediately, but then mine isn't designed to stand up to that, it is a DIY job, built for a set of nav lights not a lardy person with their butt wedged into a tractor inner tube

BogMonster is offline   Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities

Copyright 2002-2015 Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 20:41.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.