My 1983 Nacra 5.0 (recently purchased as a basket case) came with two different types of tiller tubes. One is straight and one has a bend in it that appears to be factory:



I hung the rudders today for the first time since getting the boat with the bend toward the center (opposite to my photo above). Checking rudder alignment, the leading edge was about an inch and a half wider than the trailing edge (i.e. toe out). This seems very extreme even if you are considering Ackermann angle.

The tiller tubes are both roughly 28" in length. The tie bar is 81-1/2" in length with the hiking stick attachment hole dead center at 40-3/4". The tie bar does not have the adjustable end cap.

Questions:

Is this normal?

Should I hack the tie bar off some to accomplish alignment?

Should I get the adjustable end cap?

In my experience with the Hobie 16, folks used to recommend 1/8" - 1/4" toe in. Does that apply to the 5.0 or is another setting better for performance?

Thanks in advance.

--
Hobie 16 (3 formerly)
MacGregor 25 (formerly)
Chrysler Dagger 14 (formerly)
NACRA 5.0 (currently)
High Point, NC
--

I set mine no toe in and it seems to be sailing nicely. I know on the Hobie they do recommend some toe in but I set mine dead on. Now days on the Hobie everyone races with one rudder up so the issue is kinda moot.

You might be able to get a conduit bender on your tiller tube and bend it to match the other. It would bother me having a straight and a bent tiller tube, no symmetry and I love symmetry.

--
NACRA 5.0 (current)
Hobie 16 90945 (current) Rehabbed and sold to many to count.
Hobie 18 (formerly)
Hobie 17 (formerly)
Hobie 14 (formerly)
Goshen, IN
--

You have a mismatched set. The 5.7 came with Ackerman angle tiller tubes.

Our '88 5.0 has straight tubes.
I would try to source one or the other, & hang a matched set.
If on a tight budget, just purchase an aluminum tube the same length & wall thickness as the straight tiller. Drill the rivets out of the Ackerman tiller, & rivet your new tube into the casting. The castings will be the same.
Someone here must have a tiller tube for sale.
Sell the Ackerman tube here, someone must have crashed & badly bent one.
Our 5.0 does not use an adjustable tie bar, the 5.7 came with it. Tie bars are not cheap. If you "hack it off", & screw up the measurement a bit, you are S.O.L.
The adjustable end is also about $80 IIRC, maybe Pete Begle or Dan Berger has one?
Either way, radius those sharp edges of the casting while you have it apart.



Edited by Edchris177 on Aug 27, 2015 - 10:54 PM.

--
Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
--

Thanks swaompfox. I always set my Hobies square as well, no toe in.

I'm a symmetry fan myself. I felt certain something was not right when I first noticed that I had a mis-matched set of tiller handles. I'm planning to replace the dog leg handle with a straight one. Mocking that up with the 81-1/2" tie bar, the rudders are in nearly perfect alignment. The tubing they used for the tiller handle is odd ball, 1.000 OD, 0.083 wall. I have an extra, damaged tie bar (same tubing size as the tiller handles) that I'm going to repurpose and cut a striaght handle, 28" from it.

--
Hobie 16 (3 formerly)
MacGregor 25 (formerly)
Chrysler Dagger 14 (formerly)
NACRA 5.0 (currently)
High Point, NC
--

Thanks Ed for a great tip. I did indeed your advice on the radiusing and polishing. Those edges are very sharp.

Before:



After:



It's easy to see how the sharp edges could eat up bungees and lock down lines, not to mention being very hard on the sides of the rudder.

As I mentioned above, I'm going to replace the Ackermann tube with a straight one. I noticed that the cavity that the tube is installed in is about 1/16" wider than the tube and to accommodate this they used small washers:



They appear to be of a fiberous material. Can you or anyone verify the material, size and a source for replacements?



Edited by leeboweffect on Aug 28, 2015 - 06:46 PM.

--
Hobie 16 (3 formerly)
MacGregor 25 (formerly)
Chrysler Dagger 14 (formerly)
NACRA 5.0 (currently)
High Point, NC
--

Quote

It's easy to see how the sharp edges could eat up bungees and lock down lines,

Maybe it's just the photo, but I see file lines in the metal. Take any piece of 240 grit sandpaper, just use your thumb & smooth tha tout, your bungees will luv you.

Quote

to accommodate this they used small washers:

These do not exist on any Nacra tube I have, or have seen. If you are leary of compressing the tube, just go to Home Depot & get a plastic washer. It's a tricky thing, you want to be careful about bending those castings, BUT, you don't want any slop. Even a little, at each point in the system adds up.
My 20'x10' Mystere has the sweetest rudders I've ever seen. Zero slop, both tacks balanced to steer with two fingers, at any speed or power setting.
My Nacra's, not so sweet. I've cured a lot of it, but the gudgeons are worn, so there is still slop there.

Quote

I have an extra, damaged tie bar (same tubing size as the tiller handles) that I'm going to repurpose and cut a striaght handle, 28" from it.

Free fix! IIRC the rivets are SS, (maybe monel?) hard to pull. If you operate in saltwater, buy a little tube of Tef-Gel on Ebay & dunk the rivets in it. Otherwiae you will get galvanic corrosion between the aluminum casting & SS rivets.

--
Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
--

Lee, I also bought an 83 5.0 with a set of rudders that looked just like yours. I was able get it very straight by deflecting the center with the ends supported by wood. (In other words I jumped on it till it was straight.) Maybe they're supposed to be crooked?

--
Mark Hirte
Nacra 5.0 1983 - (1st cat)
Deerfield, Il
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mhirte

Maybe they're supposed to be crooked?

With the tie bar I have, 81-1/2" long, the crooked tubes absolutely will not work.

Edchris177

You have a mismatched set.

Ed has much more experience than I do with these boats and I think he has it right.

leeboweffect

I'm planning to replace the dog leg handle with a straight one. Mocking that up with the 81-1/2" tie bar, the rudders are in nearly perfect alignment.

Simulating the setup using two straight tiller tubes the alignment was within 1/4". I'm planning to tweek the last bit of mis-alignment out of the setup by installing an adjustable end cap, Murrays Item #56-5508



--
Hobie 16 (3 formerly)
MacGregor 25 (formerly)
Chrysler Dagger 14 (formerly)
NACRA 5.0 (currently)
High Point, NC
--

correct toe-in is faster
having Ackermann is faster too (think of your car without a differential - will work but your gonna lose some efficiency)
both rudders down is faster (when they are properly set)

all that is a moot point if your not racing or your not sailing in a fleet and trying to beat everyone to the beer next stop

Quote

I set mine no toe in and it seems to be sailing nicely. I know on the Hobie they do recommend some toe in but I set mine dead on. Now days on the Hobie everyone races with one rudder up so the issue is kinda moot.