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Old 25 August 2015, 12:53   #1
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stepped hull quandry

Me again. Need help with my brainstorming.

I have twin stepped hull rib. Its on a twin bunk trailer, one set of bunks forward, one set under aft section. Nothing in middle. About 8 sets of keel rollers support the keel full length But this is where the problem lies. The keel rollers and the bunks catch in the step and I end up getting wet or the car ends up getting wet to get it off. Its a right drama, which I don't like at the slip.

Previously I had a regal with stepped hull and a sbs roller trailer. That did the same thing and it ended up with waves breaking over the roof of the old range rover a few times to get it to get unstuck.

So the solutions offered to me so far are....

My idea. Mount longer bunks, under the bunk in-front so there is no sharp edge. It would mean only parts of the hull would be supported and I would have to use the bunks to hold boat clear of keel rollers also.

SBS solution. Pneumatic first roller mounted on chassis so non tilting/swinging roller assembly.

Anglesey Marine. Slightly larger dia rollers mounted on the chassis. So non swing arm/tilting again.

Anglesey Marine again. Bank of rollers mounted on a single adjustable height bar, to allow me to compensate for height in step. ( will they be strong enough)

Any ideas/feedback from trailer guru's. I cant work out in my head if non tilting or tilting rollers would be best.

PS I am dead against launching with rope or extension bar, due to past experiences.
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Old 25 August 2015, 15:00   #2
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Extension bar is the obvious solution, what puts you off that? It would allow the boat to float off the bunks which is always going to be easier. Although a video of your current issues might help people suggest something else - I suspect it will be slipway/gradient specific.
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Old 25 August 2015, 16:02   #3
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Extension bar is the obvious solution, what puts you off that? It would allow the boat to float off the bunks which is always going to be easier. Although a video of your current issues might help people suggest something else - I suspect it will be slipway/gradient specific.
My primary slip is the main issue. It's failey steep. On the regal any weight upfront made it even worse and likely to happen. It used to rip rollers off the trailer and then could damage the hull then other times it would slide off a doddle.

Don't like ropes as had a boat flip up once and land on the leg.. Similar with a draw bar, I had trouble with traction when in a 2wd car and had to be rescued by step dad and his discovery.

Boats off the water so to speak at the mo undergoing refurb, I was hoping to solve this issue before re launch

Thanks
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Old 25 August 2015, 17:41   #4
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Have you asked the question on boatmad? They must have much more experience with stepped hull rigs?
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Old 25 August 2015, 22:01   #5
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I ended up welding my tilt section to stop the rollers jamming into the step.

The blue rollers you show in the image are what we use on aluminium boats as they are much harder than the ones designed for glass boats. Ive just replaced my blue ones as they were damaging the bottom of my boat.

Jon
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Old 26 August 2015, 07:29   #6
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Have you asked the question on boatmad? They must have much more experience with stepped hull rigs?
Yeah I did last year. Put the trailer deeper or V24s used pneumatic ones with little coats on to stop them marking hull
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Old 26 August 2015, 07:31   #7
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I ended up welding my tilt section to stop the rollers jamming into the step.

The blue rollers you show in the image are what we use on aluminium boats as they are much harder than the ones designed for glass boats. Ive just replaced my blue ones as they were damaging the bottom of my boat.

Jon
Thanks for reply. What hull Jon? Real interesting. I am thinking tilting will cause that effect. Have you had any issues since its been non tilting? No need to go deeper at all?

So those blue rollers are too hard. Shame they were a good price.
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Old 26 August 2015, 07:38   #8
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Bunk near step
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Old 26 August 2015, 08:26   #9
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You could approach the issue a different way and arrange for the boat to always float off and on. You would need to alter the trailer; axles and crossmembers need to be v shaped and the boat needs to be on as low as possible bunks. Also, if you have any adjustment in axle height, get the trailer as low as possible.
My trailer is designed this way and I launch and recover a 3000kg boat single handed. How far you reverse into the water is obviously slip angle dependent but, for me, it is usually when my rear tyres touch the water the boat stern is floating and I can reverse off using its engine.
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Old 26 August 2015, 09:19   #10
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My boat sits on bunks. I found steep slips best as I could launch without getting the rear of the van wet. Anything that wasn't steep needed an extender bar.

I bought one that comes in 1m sections (4 in all). Found that was all I needed in the end. Oh, and someone to ensure it stays straight when I reverse.

I did consider modifying the trailer / bunks and looked at all sorts of rollers, set ups etc. Also talked in depth to a trailer manufacturer.

In the end the cost of modifying everything compared to an extender was not worth it.

Having said all that now I just get it craned in/out
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