Author Topic: Help Please with Roller-Coaster Cradle  (Read 1682 times)

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Help Please with Roller-Coaster Cradle
« on: April 10, 2014, 01:50:12 PM »
Tim Willey
Username: Tim_willey

Registered: 03-2012
   
Posted on Friday, July 13, 2012 - 08:51 pm:      
I think I have a fairly standard Roller-Coaster trailer for Skylark. It all seems fine, except that when the boat is off the trailer the roller cradle always swings upside down. Recovering is therefore a rather messy affair involving wading in and trying to balance the cradle in the correct position whilst someone winches in. Haven't noticed any mention of this on the forum but I guess I must be missing something?

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Re: Help Please with Roller-Coaster Cradle
« Reply #1 on: April 10, 2014, 01:50:29 PM »
Roger Parish
Username: Roger_parish

Registered: 03-2007
   
Posted on Saturday, July 14, 2012 - 11:15 am:      
See tread "keeping rollers right way round"

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Re: Help Please with Roller-Coaster Cradle
« Reply #2 on: April 10, 2014, 01:50:44 PM »

Tim Willey
Username: Tim_willey

Registered: 03-2012
   
Posted on Saturday, July 14, 2012 - 12:34 pm:      
Thanks for that, I did look over that thread but as it was referring to an individual roller unit I must have skipped through and missed your note of also adding a 'restraining rope on the main swinging arm to stop it inverting'. Excellent, I'll certainly do the same, a nice simple fix. What puzzles me though, is how these trailers worked straight from the factory: did they incorporate a similar mechanism?

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Re: Help Please with Roller-Coaster Cradle
« Reply #3 on: April 10, 2014, 01:51:00 PM »
Julian Swindell
Username: Julian_swindell

Registered: 03-2007
   
Posted on Tuesday, July 17, 2012 - 03:11 pm:      
If I remember rightly, the Winkle Brig roller coaster has specially raised rollers to fit either side of the bilge boards. This makes the cradle top heavy compared to a conventional cradle, which is why it can flip upside down. usually just after you have reversed it into the water, which is when you don't want it to happen. My current boat has conventional low rollers, and the cradle shows no tendency to flip. On both trailers I fitted either scrunched up rubber hose, or vinyl flooring offcuts under each roller pivot to make sure each individual roller pair stayed horizontal, rather than flopping over the wrong way. Works a treat.

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Re: Help Please with Roller-Coaster Cradle
« Reply #4 on: April 10, 2014, 02:25:20 PM »

Geoffrey Osborn
Username: Geoffrey_osborn

Registered: 01-2009
   
Posted on Tuesday, July 17, 2012 - 10:12 pm:      
Hi folks. When the crane lowers Calidris on to her trailer I use a piece of 'sacrificial' wooden dowel to keep the cradle right way up. When the weight of the boat settles on to the cradle the dowel cracks, allowing the cradle to change angle, and the cradle provides - nearly - equal support from each roller. If I use the 'official' pin I don't think each roller takes its equal share of the weight. If recovering from the water I think the dowel method would still work - but I have not tried it so far.