Com-Pac Yacht Owners Association

Com-Pac Model Specific Discussions => CP-16's => Topic started by: atrometer on December 08, 2013, 12:12:47 PM

Title: CP 16 RUDDER Questions
Post by: atrometer on December 08, 2013, 12:12:47 PM
On my (new to me) CP16 the rudder blade swings up/down VERY easily.  There is no push/pull mechanism as there is on an IDA sailor.  It seems to me if you're sailing at 5 knots the water will RAISE your rudder blade at least partially???????  I've also noticed that it appears the bottom of the rudder blade is a little lower (deeper) than the keel????
Title: Re: CP 16 RUDDER Questions
Post by: marc on December 08, 2013, 03:12:47 PM
I had a similar problem on my 19 with the rudder lifting when underway.  I ended up putting a clevis pin through the rudder head just aft of the blade. It's easy for me to reach over the transom and remove the pin if necessary. I'm not concerned about the rudder hitting bottom since my sailing area is all deep water.
Marc


(http://i1062.photobucket.com/albums/t486/sail19/IMGP8195_zps394f6e5c.jpg) (http://s1062.photobucket.com/user/sail19/media/IMGP8195_zps394f6e5c.jpg.html)
Title: Re: CP 16 RUDDER Questions
Post by: Jason on December 08, 2013, 04:12:30 PM
Hi,

The bolt around which the aluminum rudder pivots is designed to be used as the pivot point for the swing-up rudder and also as a mechanism to tighten up the assembly so that the rudder does not swing up under water pressure alone.  There is a threaded handle that can be tightened so that the rudder does not swing up too easily (the handle can be seen in the photo in the post above), however over the years it may have been lost and may be replaced by a nut.  If you're missing that handle you could make one or probably order one from Hutchins in Clearwater FL.  Careful not to overtighten it, I tighten it just enough to keep the rudder down when making way.  A small line attached to the sternmost upper corner of the rudder blade is used to swing the rudder up.  There should be a cleat on the rudder stock where this small line is cleated to hold the rudder up when needed.

I replaced my stock aluminum rudder blade with a new one from IdaSailor, and I tighten the new rudder blade in the same fashion.

Hope this helps

Jason

Title: Re: CP 16 RUDDER Questions
Post by: Pacman on December 08, 2013, 05:56:48 PM
A clevis pin as shown above might be fine in deep water but if you hit an underwater obstacle something will break.  
It could easily tear the whole rudder assembly off the transom at the pintles - doing severe damage to the transon and risking sinking the boat.

Tightening the pivot bolt enough to clamp the blade might work too but it can deform the aluminum casting.
(I had a Catalina 22 that used this method for keeping the rudder blade down but it had a rudder blade that was a tight fit in the rudder casting so deformation was minimized.  My C-16 rudder blade has more clearance and would require more deformation of the casting to be sufficiently tight to hold the rudder blade in position.)

There is a much easier and safer way:

1. Drill a small hole on the leading edge if the aluminum rudder blade.

2. Insert a light line through the hole and tie a secure loop.  
(I use nylon line from Home Depot that is much like large fishing line.)

3. Take the free end up to the top of the rudderstock and tie it off. (a small cleat would be nice)

If you hit an obstacle the line will break so the rudder blade can fold back with no damage to your rudder.
Title: Re: CP 16 RUDDER Questions
Post by: Pacman on December 08, 2013, 06:01:20 PM
Quote from: atrometer on December 08, 2013, 12:12:47 PM
It seems to me if you're sailing at 5 knots the water will RAISE your rudder blade at least partially???????

No.  The rudder blade should be down when sailing. 

If the blade comes back and up, it will greatly increase the tiller pressure required to stay on course and it will require a lot of effort to steer.
Title: Re: CP 16 RUDDER Questions
Post by: Pacman on December 08, 2013, 06:05:05 PM
Quote from: atrometer on December 08, 2013, 12:12:47 PM
I've also noticed that it appears the bottom of the rudder blade is a little lower (deeper) than the keel????

Yes,  That is a good thing because it serves as an early warning of shallow water before you run the keel into the sand.

If the rudder touches bottom you know it is time to head for deeper water.
Title: Re: CP 16 RUDDER Questions
Post by: skip1930 on December 08, 2013, 06:45:47 PM
The CP-19 is fitted with the 'first' generation of the IdaSalor rudder which is not fitted with any lift rods or hold down 'detents'.
Just loosen the original jam bar that pinches the cast aluminum head onto the rudder and pull up the rudder with a line, and dog the line down.

The rudder even though it sits on bronze shoulder bushings still hangs down below the keel [+6mm] by about a 1/2 inch.
Being tired of pushing the rudder blade back down after the seaweed popped it up there is now a drilled hole and a shear bolt, later just a pin keeping it down.

It is noteworthy that these rudders be pushed 'hard forward' giving a bit of balance feel to the tiller. This rudder's leading edge is under the hull.

skip.

(http://i259.photobucket.com/albums/hh299/1930fordroadster/ComPac%2019/DSC00394.jpg)

Title: Re: CP 16 RUDDER Questions
Post by: Bob23 on December 08, 2013, 07:45:35 PM
If you look closely in this photo, you can see the downhaul I devised when I built my wood foiled rudder blade:
(http://i617.photobucket.com/albums/tt260/Bob23_photo/Koinonia%20rudder%20project/Woodfoiledblade.jpg) (http://s617.photobucket.com/user/Bob23_photo/media/Koinonia%20rudder%20project/Woodfoiledblade.jpg.html)

  I removed the gudgeon and installed a pad of 5/8" marine plywood with a vertical groove routed out in the front of it. A line runs from the back edge of the rudder, up along the transom in the groove and enters the cockpit through a PVC pipe I inserted through the transom. The line is held by a jam cleat just above the hole. Does that make sense?
  It works ok but due to the blades tendency to float, it still kicks back a bit while under sail. A second attempt is in order for the spring.
Bob23
Title: Re: CP 16 RUDDER Questions
Post by: Pacman on December 08, 2013, 10:55:49 PM
Bob23,

That's it exactly.

You might try a small cam cleat on the rudder stock so you can snug your line to keep the rudder blade in the forward position.

If you use a small cam cleat it will pull free if you strike an underwater obstruction.

Looks good.
Title: Re: CP 16 RUDDER Questions
Post by: capt_nemo on December 08, 2013, 11:04:33 PM
atrometer,

As Skip pointed out, ALL RUDDERS, whether they be original factory or foiled replacements, MUST BE SECURED IN THE FULLY FORWARD POSITION!

A rudder even SLIGHTLY back from its most forward position will cause noticeably increased weather helm when steering the boat depending on how far back it is out of "working" position.

Many complaints of "excessive weather helm" are due in large measure to a rudder out of designed "working position".

Photo of a rudder left to gravity to find its own position before tightening.

(http://i1125.photobucket.com/albums/l594/CPYOA/Sun%20Cat%20Maintenance/IMG_0393.jpg) (http://s1125.photobucket.com/user/CPYOA/media/Sun%20Cat%20Maintenance/IMG_0393.jpg.html)


Photo of same rudder PUSHED forward as far as it will go before tightening. Toggle back and forth between the photos to notice TWO things. First, in its proper position (below) the leading edge of the rudder is parallel to and follows the transom line. Second,  the bottom tip of the rudder below "in position" is about 6 inches forward of the tip of the rudder "out of position" above AND is actually UNDER the hull of the boat.


(http://i1125.photobucket.com/albums/l594/CPYOA/Sun%20Cat%20Maintenance/IMG_0392.jpg) (http://s1125.photobucket.com/user/CPYOA/media/Sun%20Cat%20Maintenance/IMG_0392.jpg.html)


Hope this helps.

capt_nemo
Title: Re: CP 16 RUDDER Questions
Post by: atrometer on December 10, 2013, 11:01:26 AM
I called Compac for an "official" answer.  They said I needed the "lever" to tighten the bolt, and they cannot recall a broken casting unless perhaps over-tightened.  (Just snug enough to hold it down).  I ordered the bolt and lever. They did know of one case of someone using a wooden dowel - rudder destroyed.  Thanks for all your help and advise!!!!
Title: What do you think of this shear pin?
Post by: marc on December 10, 2013, 11:37:48 AM
I had discussed the need for a shear pin or some type of rudder hold-down arrangement with the customer rep at Rudder Craft. This is what he recommended:
(http://i1062.photobucket.com/albums/t486/sail19/Screenshot2013-12-10at112209AM_zps031b0d2c.png) (http://s1062.photobucket.com/user/sail19/media/Screenshot2013-12-10at112209AM_zps031b0d2c.png.html)
It is a delrin shear pin that is suppose to break before the rudder does.
At this link - http://www.ruddercraft.com/catalog/product_info.php?cPath=60&products_id=298, it gives an example of the pin's use on a Macgregor boat and says it will release with 150 lbs of force. Can someone elaborate and tell me how much force that is? I've got nothing to relate it to and don't know whether it would work on our Compacs or not. It certainly would be more forgiving than the stainless steel pin I'm currently using!
Thanks for any input.
Marc


Title: Re: CP 16 RUDDER Questions
Post by: Pacman on December 10, 2013, 03:43:53 PM
The delrin shear pin is a brilliant solution!

It will positively hold the rudder in the correct position yet it will shear upon impact thereby preventing damage to either the rudder or the boat.

My light line accomplishes the same goal but the delrin shear pin is simple to use and inexpensive too.

I think that is the best solution discussed so far.

Kudos to Ruddercraft for that one.
Title: Re: CP 16 RUDDER Questions
Post by: NateD on December 11, 2013, 08:41:18 AM
In a previous discussion on the shear pin topic (http://cpyoa.geekworkshosting.com/forum/index.php?topic=6883.0) people suggested: plastic bolts, golf tees, wood dowel, zip ties, or piece  of rolled up beer can. It seems that a plastic bolt (either from Rudder Craft or the local hardware store) is a good choice.

I image 1,200 pounds moving at 1-2 knots would generate 150 pounds of force on the tip of the rudder if it hit something, although I have no math to back it up.
Title: Re: CP 16 RUDDER Questions
Post by: nies on December 11, 2013, 04:59:22 PM
Going back to previous disc., a drilled hole with a shock cord of proper length provides a safe alternative, cheap and quick..................no worry about pressure to shear anything, works on my boat....nies
Title: Re: CP 16 RUDDER Questions
Post by: Pacman on December 11, 2013, 06:53:14 PM
Quote from: nies on December 11, 2013, 04:59:22 PM
Going back to previous disc., a drilled hole with a shock cord of proper length provides a safe alternative, cheap and quick..................no worry about pressure to shear anything, works on my boat....nies

Good point.  A shock cord would work every bit as well as any of the more complicated or risky solutions we have discussed.

I especially like the simplicity and safety of that solution.

Sometimes we seem to overcomplicate things where a simple elegant solution will be the best.
Title: Re: CP 16 RUDDER Questions
Post by: marc on December 12, 2013, 07:41:08 AM
A question for those of you using a line or shock cord.
Did you drill the hole in the metal stock or the blade. If on the blade, how far down and how far from the edge? Is your cleat on the rudder head, tiller or transom?
My concern is if I'm going to drill a hole in the rudder, then I want to be sure it is placed so that the line has enough leverage to keep the rudder in place. It seems that the lower the hole, the better the leverage, but on the other hand, I don't want to compromise any of my rudder's lift by having a line in the water disturbing flow around the blade.
Bob23's solution of bringing the line right up against the transom looks like it creates the best leverage but that set up is more elaborate than I care to get involved with.




Title: Re: CP 16 RUDDER Questions
Post by: nies on December 12, 2013, 09:11:06 AM
I have a IDA rudder and drilled my hole one inch down and one inch in from leading edge, placed a small clevis through hole attached cord and ran it over bottom of rudder stock and back to clevis.....the angle provides the right amount of leverage...................( front top of rudder blade).............nies
Title: Re: CP 16 RUDDER Questions
Post by: marc on December 12, 2013, 10:09:23 AM
Nies,
Would you have a photo? Not quite understanding the setup from your description.
When you say:
Quoteran it over bottom of rudder stock
- well, I just don't understand. Sorry to be so dense.
I just received by IDA blade and it sounds like your system may be the way to go.
Marc


Title: Re: CP 16 RUDDER Questions
Post by: nies on December 12, 2013, 11:30:12 AM
Sorry can not do photos yet........your rudder stock has two bolts holding it on to the plate attached to the boat, run shock cord behind the bottom bolt, length of  will depend on attachment point.....nies
Title: Re: CP 16 RUDDER Questions
Post by: marc on December 12, 2013, 05:11:17 PM
Hello nies,
OK. I get the idea.
One more question - Is the hole going through the rudder 1" down the metal part or 1" down the plastic part of the blade?


Title: Re: CP 16 RUDDER Questions
Post by: nies on December 12, 2013, 05:31:36 PM
The hole is one inch down and one inch in from leading edge on the plastic part............talked to IDA before I drilled in plastic and they said "no problem" just make sure far enough in, I figured one inch would work with the 1/4 inch clevis pin hole to leave enough material on plastic blade, so far has worked great and hope I have been a help............good news if you don't like it you  have almost nothing invested and a small hole in rudder blade which could be filled ........five minute job................spent many nights lying in bed with pulleys ,lines ,weights and on and on to fix problem and finally came to me "simple is best"......nies
Title: Re: CP 16 RUDDER Questions
Post by: marc on December 12, 2013, 06:23:14 PM
Thanks so much.
Marc
Title: Re: CP 16 RUDDER Questions
Post by: capt_nemo on December 12, 2013, 09:23:07 PM
Once again,

Make sure you have enough leverage on your line to PULL the rudder FULLY FORWARD to its down position STOP, and hold it there, before inserting plastic pins or simply cleating off!

Failure to do so risks ADDING EXCESS WEATHERHELM as shown by my photos in a post on page 1 of this thread.

capt_nemo

Title: Re: CP 16 RUDDER Questions
Post by: atrometer on January 11, 2014, 05:50:46 PM
I took several pieces of advice.  #1 - I removed the rudder, epoxied a large fender washer around the hole, and reinstalled (very snug).  I had already ordered the replacement bolt/nut/handle from Compac, so I snugged it up a little-I think it will stay there fine.  BUT being a guy that likes backups for my backups I also drilled a hole in the rudder 1" down - 1" in from the leading edge, installed a 1/4" clevis and pin, ran a 3/8" 18" long bungee from the clevis over the top rudder mount and back down to the clevis.  Now I'm SURE it will stay down!!!

Thanks everyone for your help!
Title: Re: CP 16 RUDDER Questions
Post by: dontpanic on January 11, 2014, 11:55:10 PM
Capt_Nemo: not exactly on topic, but if your shop is as clean as the shop floor we need to see photos!
Title: Re: CP 16 RUDDER Questions
Post by: Pacman on January 12, 2014, 08:06:15 AM
Quote from: atrometer on January 11, 2014, 05:50:46 PM
I took several pieces of advice.  #1 - I removed the rudder, epoxied a large fender washer around the hole, and reinstalled (very snug).  I had already ordered the replacement bolt/nut/handle from Compac, so I snugged it up a little-I think it will stay there fine.  BUT being a guy that likes backups for my backups I also drilled a hole in the rudder 1" down - 1" in from the leading edge, installed a 1/4" clevis and pin, ran a 3/8" 18" long bungee from the clevis over the top rudder mount and back down to the clevis.  Now I'm SURE it will stay down!!!

Thanks everyone for your help!

August,

That sounds like an excellent solution.  If you do run into anything on the bottom your rudder will be able to safely swing free without damage but it should stay in place for sailing.

Title: Re: CP 16 RUDDER Questions
Post by: marc on January 12, 2014, 02:02:29 PM
My solution was to take a piece of linoleum floor tile and cut it to the shape of the rudder's aluminum plate that fits into the rudder head. It was just the right thickness to keep the rudder very snug. Now I'm not afraid to really torque down the tightening screw. I'm going to give this a try before drilling any holes for a pin. (On page 1 of this thread I showed you a photo of a clevis pin in place to hold down my original, aluminum plate rudder. I now have a Ruddercraft rudder and the placement of the existing hole through the rudder head won't work. I don't want to drill anymore holes unless I have to.)
Marc
Title: Re: CP 16 RUDDER Questions
Post by: atrometer on January 12, 2014, 03:11:57 PM
I think that's a good solution.  I can't believe that the water can exert 150 #s (delrin pin) on that thin edge.  I can push the rudder up now, but I don't think it's close to 150#s.
Title: Re: CP 16 RUDDER Questions
Post by: capt_nemo on January 12, 2014, 09:04:27 PM
dontpanic,

The floor you saw in the pics above is in my friend's large 3 - car Man Cave.

It has very high doors and I'm able to back my Sun Cat in to work on it once in a while.

Took the opportunity to take pics of the rudder to illustrate the WRONG and RIGHT positions when down and "ready" for use.

capt_nemo
Title: Re: CP 16 RUDDER Questions
Post by: dontpanic on January 13, 2014, 12:21:13 AM
Capt_Nemo. Thanks, A good friend to have.

Don't Panic