Adding Trailer Wobble Roller Assembly - Size?

[Jacalore]

My trailer has only a single roller and two wobbles (one each side) supporting the stern of my 17' boat (about 2000 lb including 500 lb engine). I'd like to add another pair of wobble assemblies for additional support. How do you determine what size/type you need?

I've attached a pic showing about 6" of space at one point... frame is 2"x3"

Thanks.

 

[Frank Acampora]

Re: Adding Trailer Wobble Roller Assembly - Size?



That looks very much like the trailer I have under my 21 foot cuddy. It has one bogey with two sets of keel rollers and chine rollers plus a bar at the front with a set of keel rollers and chine rollers. In my case, I removed the bolts holding the two keel roller assemblies to the frame and added three axles and three more keel rollers.

 

[bonz_d]

Re: Adding Trailer Wobble Roller Assembly - Size?

Just as an FYI those rollers that you pictured are not wobble rollers. Those are keel rollers.

Wouldn't want you going out and looking or asking for the wrong items.

 

[Jacalore]

Re: Adding Trailer Wobble Roller Assembly - Size?

Just as an FYI those rollers that you pictured are not wobble rollers. Those are keel rollers.
Wouldn't want you going out and looking or asking for the wrong items.

Thanks, but yeah, just a keel roller there, would like to add wobble roller assy. Thinking about something like this: Single Wobble Roller Assembly - Ve-Ve T-980 but not sure about how to size what I need. Plus there's no weight rating on this assembly. Are they adjustable?

 

[bonz_d]

Re: Adding Trailer Wobble Roller Assembly - Size?

Those look good and should work. Length is not as important as width between the pair on each axle. You want them wide enough so that thay wont land on any strakes under the boat. The other issue I see is that there is no adjustment for height for fine tuning if the cross members on the trailer are flat and level.

 

[Jacalore]

Re: Adding Trailer Wobble Roller Assembly - Size?

That's exactly my question, bonz... there must be a way to adj the gap, no? And what's the rule of thumb? Is there any give to the rollers? I'm just not gettin this... I must be dense!

 

[Frank Acampora]

Re: Adding Trailer Wobble Roller Assembly - Size?



I am not saying those won't work, but they will be a lot of trouble to adapt to your trailer.

REASON: The cross member is bent to a certain specified angle and pivots on the frame of the trailer. When you load the boat, the existing keel rollers push down on the center of the cross member and this raises the outer chine rollers into contact with the hull. The steel members that carry the chine rollers are designed to a specific angle both to match the bend in the cross member and to rise to the correct height. Without some trailer frame modifications or adding another bent cross member and roller assembly, adding extra keel rollers as I demonstrated in the photos is probably the only option with this type trailer.

BTW: The cross member has two sets of holes in each end and the frame pivot also has two sets of holes. By varying the position of the cross member in the holes, you can adjust both its height and therefore the boat's height above the trailer frame (and axle)

 

[Jacalore]

Re: Adding Trailer Wobble Roller Assembly - Size?

Okay, I see the extra holes, for adjustments. Thanks, Frank.

 

[Frank Acampora]

Re: Adding Trailer Wobble Roller Assembly - Size?

Just edited to add photos.

 

[bonz_d]

Re: Adding Trailer Wobble Roller Assembly - Size?

The real problem and pain comes from the trailer frame. If all the crossmembers are straight and level then when putting the roller trucks on it raises the boat and it will sit very high on the trailer.

The trucks that you posted a link to bolt on to a crossmember which doesn't have to move/piviot because the bars that the roller axles mount to piviots as do the axles that hold the rollers.

All wobble roller trailers that I've ever seen do not have keel rollers on the end of the trailer. They are usually midway up the trailer. The idea being that you want the wobble rollers to contact the bow so that it centers it and then the rollers piviot and rotate as the hull is loaded.

 

[Jacalore]

Re: Adding Trailer Wobble Roller Assembly - Size?

It loads ok... most of the time. I usually launch/retrieve solo. I'm concerned about the weight in the back with so little support. Here's a couple shots (fore/aft) of the wobble and roller positions. Don't think the trailer was designed for this boat... I travel 40 - 50 mins to ramp.

 

[bonz_d]

Re: Adding Trailer Wobble Roller Assembly - Size?

From the last set of pictures you posted I don't see why the ones you linked to wouldn't work. Just replace the ones on the end of the trailer. Adding 4 more rollers total would help bunches and help distribute the weight even better..

There are many different roller truck assemblies made out there, keep looking and you'll find ones that work. There are even ones with 8 rollers per side. Shoreland'r makes one with 6 rollers per side.

 

[Jacalore]

Re: Adding Trailer Wobble Roller Assembly - Size?

Thanks.