Flat rollers (vs. V-shape)?

[DanF]

Hi all

Before I drop $200 to replace all the crumbling rollers & shafts on my 23's Magic-Tilt trailer... I'm wondering whether anyone out there uses flat (rolling-pin shaped) rollers, instead of the "V"-shape rollers that seem to be standard?  Looking at the flat profile of the 23's keel bottom, it just seems it would make more sense to have a flat roller.  I imagine there might be a downside in terms of getting the boat centered, but it seems that could be accomplished by the guide boards on either side.

I did a search for this but didn't find much, other than one post from a CP16 owner in 2005 who had flat rollers.  Interested to hear any first-hand experience, and/or completely unjustified speculation.

[brackish]

Here is what I think without any real comparative knowledge.  When I went under my 23 to do the bottom painting, I noticed that the rollers compress a bit and the contact surface is much greater than one might expect with tapered V-rollers.  Additionally, most of the load is concentrated on the sides of the keel, the strongest place.  The keel is a foil with a  rounded forward edge and tapering aft.  The keel guides are there to get it started on the trailer and, in my case at least, have the width set at a distance that gives about an inch of clearance both sides to the widest part of the keel.  If you had flat rollers, and you retrieved a little crooked as you will with any wind or current, you could get the boat abrading one keel guide forward and the other aft and the additional friction would make the winching process much more difficult.  And it would continue to try to run off without the tapered rollers to correct the path.

So I guess I would ask why would you mess with something that works?

[Sox]

Always thought maybe flat rollers would last longer because they distribute the load more evenly. I think flat rollers cost more too...

[DanF]

"So I guess I would ask why would you mess with something that works?"

Ha, fair question.  Because it seems it could work better?  We always have great trouble getting the boat launched-- does not remotely want to slide off the trailer when the truck exhaust is starting to go under water.  Part of that may be the cruddy, cracked old rollers (hence the replacement) but I thought maybe having the weight distributed more evenly across the keel width might conceivably help the rolling too.  Also, to Sox's point, looking at the way in which the the old rollers cracked (at the outside edges/corner), it does look like it was the pressure there that contributed. 
the center areas are in very good shape.  Though for all I know they are 25+ years old so maybe roller longevity is irrelevant to this. I agree, though, that the centering is probably a nice feature of the V's.

"I think flat rollers cost more too..."

Actually the ones I looked at (polyurethane by Stoltz) were about the same for V's or flats.

[brackish]

We always have great trouble getting the boat launched-- does not remotely want to slide off the trailer when the truck exhaust is starting to go under water.

That's kind of strange.  I think maybe your tongue is too short, maybe you need to add an extension.  Or maybe you are using a particularly shallow slope ramp.  By the time my rear tires hit the water, my boat has floated off the trailer, I just give it a gentle shove to get it moving backward, but at that point it only has a little contact with the forward most roller.  Five different ramps, all the same.  Retrieving, I lead it in with a bow line until contact and I have to crank the winch to bring the boat forward to the chock about 30" max.  It has never been difficult.  I have always launched and retrieved single handed.

my rollers are 14 years old, zero cracks on them anywhere.  The only item that takes a beating is the front chock which catches the bobstay tang at the wrong place and it gets eaten up on a road trip.

[Potcake boy]

It sounds like a shallow ramp to me as well. I have used a pretty shallow ramp a few times with my 19' and it was very difficult to launch it without backing in too far for the vehicle. You might give some thought to the car ramp solution I described here before. When you get your tires in the water as far as you feel prudent, place a ramp behind each wheel then proceed. this will allow the vehicle to travel farther back and will tilt the trailer at the same time. I can't take credit for the idea though I think it very clever.

[DanF]

I don't think our ramp is unusually shallow.  Believe it or not I've geek-ily gone around and taken measurements at several local ramps with my iPhone inclinometer-- rough, I know, but they've all been around the 7-9º range, which seems normal.  I've even tried launching without the motor, gas tank, & battery to see whether taking all that weight off the stern would help float her off-- nope.

I do have a tongue extender, which certainly solves the problem, but it is REALLY long (8 feet?) and creates another problem, because I find getting that thing installed between the trailer and the truck to be like refueling a plane in the air (i.e., challenging.)  Trying to do it at the boat ramp is particularly stressful

Next spring I'm going to try a slightly higher trailer mount (I think we've been running a bit low) and the new rollers.  If that doesn't work, I'm definitely going to try Potcake's ramp trick (thanks for that idea).  Or I might try a more sailor-ly approach:  row the anchor out in the dinghy and try to kedge her off the trailer!

[zimco]

YOU MIGHT TRY THE STOLTZ Super Rollers  made of polyurethane.  MOUNTED ON STAINLESS STEEL ROD, THEY ROLL VERY NICELY.  USE THE V-SHAPED ROLLER FOR THE FIRST ROLLER WHERE THE KEEL FIRST MEETS THE TRAILER, THEN FLAT ROLLERS THE REST OF THE WAY.

CONTESSA