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Old 15 June 2015, 11:29   #1
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Multi roller trailers - fine tuning

So, I've got the DeGraaff trailer now with lots of rollers, and I've finally got around to fine tuning it so the boat sits exactly where I want etc - just need to move the axle back a bit to increase the noseweight and I'll be done with the setup.

The only issue that I have is that the weight isn't evenly distributed across all the rollers in the banks. In fact, on the 5x2 banks, most of the weight is on 2 pairs of rollers, there isn't much on another 2 pairs, and at least one pair on each bank isn't touching the hull at all (you can rattle it back and forth with a few millimetres of clearance from roller to hull).

Is this 'normal' with multi roller banks? The DG rollers are quite hard (polyurethane or something), so there is no squish in them. I'm not sure if the issue is the shape of the hull, or slight variations in the height of the mounting holes that the rollers go through, or maybe a bit of both. The boat rolls on and off like a dream, if you lift the drawbar of the trailer about a foot it will start to roll backwards just with gravity, so I'm happy with the setup, but I'd prefer the load to be distributed more evenly.

I figure that one option is to take the weight of the boat and then file out the holes slightly on the highest rollers, to sit them down a bit further and spread the load more evenly when the boat is right on the trailer in the towing position.

Any other ideas please?

(Note the photos are not the boat as sitting on the trailer now - I have moved it forward so the rear roller is closer to the transom)
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Old 15 June 2015, 11:39   #2
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Mine is the same. The only way you will ensure all are in contact is to only have 2 sets of rollers per support. essentially the rollers are on a flat bar and you are trying to support a curved shape, so even loading on all won't happen. My back rollers are fairly evenly loaded, as the profile is flat, but at the front I also have gaps between rollers. The keel is well supported though so not a concern.

Phil M
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Old 15 June 2015, 12:23   #3
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Quote:
Originally Posted by Phil M View Post
Mine is the same. The only way you will ensure all are in contact is to only have 2 sets of rollers per support. essentially the rollers are on a flat bar and you are trying to support a curved shape, so even loading on all won't happen. My back rollers are fairly evenly loaded, as the profile is flat, but at the front I also have gaps between rollers. The keel is well supported though so not a concern.

Phil M

Like wise, I've never been able to get even loading on every roller, even with the superduper new trailer. You would need fully independently adjustable rollers/arms/cradles. With a bit of tweaking you can get it pretty close. A common mistake is having too much weight on the winch post, try backing the post away from the boat when the boat is fully on the trailer, you might find that the boat will drop into the cradles a tad further. Then move the winch post to the boat.


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