Locked Rudder Casting Set Screw

My rudder is not staying locked down as well as it should however the set screw in the rudder casting is jammed in there really good so I can't adjust the tension. I have replacement parts but the question is how do I get the old set screw out.

I have tried lots of force with a large screw driver and WD40. The set screw is now starting to get pretty chewed up.

Any advice would be appreciated.

Drill it out to the minor diameter of a 3/4" thread, pick out the remaining pieces of screw from the casting threads, then chase the threads with a tap if necessary and install a new screw.

sm

ummmm, nevermind lol

Bruce: Just to clarify, I believe srm is referring to the delrin screw in the lower casting that adjusts the plunger (and therefore lock down tension on the cam), whereas greensnopro is referring to the screw in the upper casting that adjusts the rudder rake plate (if you even have that....older castings do not).

There are a lot of threads here on delrin screw removal....even including burning the it out....a nasty, potentially toxic option. I've done the srm option, and it's tedious but workable. Here's a video where a reverse cutter is used to make it easier:

https://www.youtube.com/watch?v=zUUA7l6fzIk

If you don't have the 3/4 inch tap, using a 3/4 inch bolt is a cheaper option.....chase a little, back it out, clean. repeat. Use a little tef-gel, lanocote, or anti-sieze on the new delrin screw.

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Jerome Vaughan
Hobie 16

Yep rattle 'n hum I was thinking Bruce meant the top adjuster screw, I figured he had it stripped and was using the screwdriver and a hammer to try and turn it out. My mistake, the delrin screw Is a straight screwdriver screw I forgot so that makes alot more sense.

Well I guess I should have tried searching a bit longer as a previous post already goes over the same topic. Here it is:

viewtopic.php?f=14&t=50734&hilit=rudder+casting

Yes I am talking about the delrin screw. What a pain!

But after looking at the casting more and after thinking about the potentially of messing this up, I think I will reassemble the rudder assembly and first try adjusting the upper rudder plate. Maybe that will solve my problem.

I also have castings from a 79 boat that I could potentially restore. I would imagine these would be fully compatible with a 2004 boat?

Bruce: I'm not sure that your 79 lower castings will be exactly compatible with your 2004 uppers (which you really want to keep since they have the rake adjuster plate). I'm betting that if you get everything cleaned up on the 2004s, replace cam and/or other parts (besides the delrin screw) as needed, and tune it all up, she'll be fine. A buggered cam, sticky/galled plunger, and/or poor rake adjustment can cause all kinds of problems. On the other hand, when everything's right, it doesn't take much pressure on the cam to keep the rudders locked down correctly. If you haven't already, follow the Support link above to the H16 page, and read all the rudder maintenance and tuning stuff. Then for rudder rake, I'd do like most folks and just remove the set screw in the front of the lower casting (it doesn't do much). After that, I'd rake them as far forward as they will go without forcing them so much that something binds. I dab of white lithium grease between the cam and plunger helps a lot. Let us know how it goes!

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Jerome Vaughan
Hobie 16

It's pretty hard to mess this up. The nylon screw is very easy to drill and it already has a hole thru its center which will guide your drill. It definitely helps if you can put the casting in a vice, or at least clamp it to something solid.

The other option is to heat up a large flat screw driver with a torch and jam it into the screw to get better engagement between the screw driver and the screw.

I would not count on '79 and '04 castings being compatible. The parts may work together, but they also may not. There have likely been subtle changes and/or wear on the tooling used to make the castings over that 25 year period.

sm

Just be very careful not to inhale the fumes or get them in your eyes. Nasty stuff.

The manufacturing process was completely changed in that time period and older castings have much more dimensional variability.

After adjusting the upper rudder plate and lubing the cam and plunger it seems to be working better now. I'll leave the rebuild until the end of the season.

I've melted out many of them with a propane torch. Take out the cam, and do it outside on a day with some breeze to carry the toxic fumes away. You can make a tap to clean out the threads with a regular bolt. File in cutting edges. I've used the same bolt/tap for 30 years.

Gary Willcox also wrote an illustrated article in ON THE WIRE, vol.1, issue 8 titled: Rebuilding the Hobie Rudder Cam Assembly - Controlling When and Where Your Rudders Kick Up

http://www.thebeachcats.com/OnTheWire/earthlink/_mattson/hobie/archives/v1-i8/feature2.htm

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Tim
84 H16
82 H16
87 H14T
Tortola Sails: 115222
Blue Prism Sails: 88863
Clearwater, FL

With sailing season being only about 6 weeks away I finally got back to this project.

Matt Bound's trick of heating an old screwdriver to red hot and plunging it into the delrin screw worked pretty good on the first casting. Of note, I had to put an iron pipe over the end of the vice grips before I could generate enough torque for the screw to let go.

On the second casting, I was not so lucky. I was applying so much torque that the screwdriver handle shattered. The steps to get this straightened out were:

- With a propane torch I heated the delrin screw to soften it so that I could remove the screwdriver blade.
- I drilled out the screw with 1/2 spade bit. This is probably not the best type of bit to use but it what I had that was long enough to work with the casting. I think the hole is 5/8. I used 1/2 as I did not want to damage the thread.
- I heated the screw again with the torch to remove a bit of material at the opening. This allowed me to get a 3/4 course thread bolt started on the threads.
- I converted the bolt into a tap by cutting some slots cut into the thread using a hacksaw and then tapped out the remaining material.

What a pain! But it's done.

Be sure to coat the threads of the new screw with anti-seize to help prevent it from freezing up again.

sm