Trailer side support -wobble rollers vs bunks

[Yara50]

here are some pics of wobble roller modifications. On reflection, I think wobble rollers are good for the rear set, but flat soft pads at the bow end will provide more gentle support during trailering.

[Yara50]

If you dont tilt the trailer, she may need a little encouragement to slide off. Alternatively, if you do tilt, get out of the way of the painter as she shoots off!

Note the pivoting bunks at the bow end, wobble rollers aft.

[geoffr]

Hi Ian:

As a matter of interest, how long is the draw-bar on your trailer, say from winch to ball socket?

Also, do you normally immerse your trailer wheels past the hubs to launch? (I know this may vary with depth and steepness of ramp or launch area.)

Cheers.

[Yara50]

The photo is not Yara but Abel Tasman, which does not have tilt on the trailer. Yara's trailer does have tilt, and we back it in until there is about 50 cm of water at the end of the trailer. This usually means that the hubs are just submerged. Note our thread on having proper seals on the wheel bearings.
http://www.investigator563.com/forum/vi ... p?f=4&t=77

From this position, or even slightly higher, tilting will have the boat shoot off

[Rod]

Trailer is fitted with wobble rollers to support sides. All rollers are adjusted so 100% of the boats weight is supported by the bottom rollers and the wobble rollers are adjusted to just touch the sides. I have noticed when the boat and trailer is towed the trailer flexes which allows the wobble rollers to move. Also depending where the boat is sitting on the trailer (sometimes a little off centre) some of the wobble rollers will not make fiull contact with the hull and as there name suggest will wobble and make a noise when towing.

In all the boat freely lauches from the trailer with minimal effort and fairly races off the trailer.

It is not necessary to put the wheel bearings in the water to launch, however I usually do to reduce the chance of the stern of the boat from hitting bottom. When the trailer tilt is released the lauch angle seems to be pretty steep and there is a fair bit of boat length aft of the axles.

[Yara50]

Rod
Your trailer is pretty much stock standard. Mods I did to this design started with countersinking the bolts holding the wooden rails, as they were damaging the keel on retrieve. Then I added wobble rollers at the end. First one set, then another further along the trailer. This made sure the boat is centred, and also helps in cross wind retrieve.

Wobble rollers

P6210447 (WinCE).JPG (15.44 KiB) Viewed 6587 times

[Andrew]

This is a great thread, thanks for the posts and excellent trailer pics, know what a stock standard Investigator trailer looks like now. My trailer must be from the early days-- I'm thinking of doing some modifications to it, the side bunks are one item..I don't have keel guide woods either. Have the trailer out from under the hull and will get some photos of it.

[Yara50]

Just thinking recently that it is a good idea to lower the rear (aft) wobble rollers or support pads during launch/retrieve by a short, say 30mm, distance. There is a small amount of bulge in the hull around the miships area, and lowering the pads provides clearance for it to get past easily during the launch.

During trailering I am also pondering making some support pads to go over the wobble rollers and spread the load over a larger area of hull. (See posts on trailer hull damage.)http://www.investigator563.com/forum/vi ... ull+damage

See also http://www.investigator563.com/forum/vi ... ?f=4&t=561

[Yara50]

I have concluded that the hull dents were caused by the combination of wobble rollers, and neglecting to lower the rear wobble rollers during launch and retrieve.

As the deeper part of the hull moves past the rear supports, they try to lift the whole boat up, imposing a high point load. The wobble rollers on the outside are against a more curved part of the hull, which is very strong, and the pivoting action then transfers the load to the inner rollers, pressing on a flatter, softer part of the hull. Not good!

Moral of the story: LOWER THE REAR SUPPORTS during Launch/retrieve.

Next problem, trailer deflection during transport shifts load onto wobble rollers during transport, causing hull damage.

Looks like the original design concept of carpet covered pads was the best solution. I still want the wobble rollers to help keep the boat upright during retrieve, when there is only a light load if I have lowered them a touch.
Solution:
I have made removeable pads over the rollers to spread the load during trailering.

Glued and screwed plywood.

You can just see the dent inboard of the rollers, but extends to the line of the inner roller.

[Steve]

Or you could choose to go down this path and use 16 rollers, 8 a side.