bent striker rod

yurdle wrote:

Man, those Stainless pop rivets are tough.

Tough to remove or install? Right tool for the job and they're not that bad, although certainly quite a bit stronger than aluminum.

Install.....I have not used stainless pop rivets before. I have what I thought was a decent tool, but apparently it is lacking leverage. It took everything in my old arthritic hands to snap those rivets.

Thanks again guys!

yurdle wrote:

We didn't hold the striker below or worry about the beam, and had nothing over the threads. Ball screwed right back on. The skipper was so stoked after his first sail, then dropped me off to head north. Got a call hour later he tried to go under a bridge, hit abuttment & split bow 3' crack. He was a bit depressed, but I talked him into fixing it himself. Couple days later, he called super stoked about the fix & now a very confident sailor! Pete

I love this. Nothing inspires (over?) confidence like breaking and fixing your boat.

Confidence increasing, over-confidence on the way!

Go to Harbor Freight and get yourself a wishbone type pop riveter (Princess Auto in Canada). Best $15 you will spend on your boat, the normal riveters just don't have enough leverage for normal people to pop more than one stainless rivet per day or so and you might break them.

Wolfman wrote: Go to Harbor Freight and get yourself a wishbone type pop riveter (Princess Auto in Canada). Best $15 you will spend on your boat, the normal riveters just don't have enough leverage for normal people to pop more than one stainless rivet per day or so and you might break them.

Is this it? Looks a bit more substantial.
Mine is an Ace Hardware and looks pretty standard. You are right about the limited number per day. I didn't think I could do any more than three a day with it. My Power right system is going to take about ten rivets and I didn't know how I would get it done? So, this is the answer?
Scott

klemens wrote: Is the silicon necessary?
Gary

Yes. Here's why . . .

Be sure to pretension the beam 3/8". Then turn the top nut down snug against the beam,I mean "snug", not gorilla force. Occaisionally give an upwards yank on the V brace strap, it shouldn't move more than 1/4". If it does, tension the beam a bit.

It seems obvious, but I know people have forgotten this, I should have added, BE SURE TO BACK OFF ON THE TOP NUT BEFORE TURNING THE BOTTOM ONE UPWARDS!

scotts1w wrote:
Thanks Comrades. I used to bend my sons steel axels to adjust camber and caster on a soap box derby car. Ed's info was a good refresher. Here is the repair and my tools. I used two nuts for better control. I read Ed's album here: http://www.thebeachcats.com/pictures/?g2_itemId=73301 Excellent primer, nice work.

May not be perfect but I expect it to get me through the season.

Your pictures didn't work, it looks like you tried to link to a picture in a Gmail email message. So you can see it but nobody else can. To share photos on here you'll need to either create a photo album (Beachcats Technical for this) or upload them to something like Photobucket.

mummp wrote: [quote=klemens]Is the silicon necessary?
Gary

Yes. Here's why . . .

Is this an issue on fresh water boats as well?

mummp wrote: [quote=klemens]Is the silicon necessary?
Gary

Yes. Here's why . . .

Is the repair for this a new beam?

scotts1w wrote: [quote=mummp][quote=klemens]Is the silicon necessary?
Gary

Yes. Here's why . . .

Is the repair for this a new beam?

If you want to do it right, yes a whole new beam is the only way to go... I too did this repair and when I reassembled it I used some anti seize bronze paste mixed with some waterproof axle grease..

After that every year I would take it apart, clean all the components, and reassemble with the goop I mixed up.. Never had a sign of electrolysis after that.

scotts1w wrote: [quote=mummp][quote=klemens]Is the silicon necessary?
Gary

Yes. Here's why . . .

Is the repair for this a new beam?

In this particular case it was. If you have galvanic corrosion like this in one spot, you can bet that you have it in other areas. In my case, the SS dolphin striker V-bar beam bolts had caused similar excessive corrosion, not an area you want issues. Also, the aluminum compression tube inside the beam (that the dolphin striker rod goes through), was totally seized to the rod and you could no longer adjust pre-bend to the main beam. If you have a boat with these issues, you will also likely have frozen beam bolts, and if the mast is original to the boat, your tang rivets and hound rivets will also have caused corrosion to the alum they are seated in. Food for thought. . .

Two important maintenance items:
1) isolate dissimilar metals (marine grease and silicone for rivots)
2) and for those of you who have been around from the days of the old site, as John S. so eloquently stated "make sure to exercise your nuts"

I understood that it is not as apt to happen in fresh water.
But stray current in a marina can trigger a problem in fresh water.... Is this correct?
What should we watch for? Just inspect? By the time one finds a problem damage has probably occurred, right?

scotts1w wrote: I understood that it is not as apt to happen in fresh water.
But stray current in a marina can trigger a problem in fresh water.... Is this correct?
What should we watch for? Just inspect? By the time one finds a problem damage has probably occurred, right?

It can happen in fresh water too...may take longer

You have several things in your favour Scott, freshwater, & Ohio,(the season is much shorter, & the off season is cold).
The corrosion in the photos is a result of ion migration between metals with different electrical potentials. In very simple terms, if two dissimilar metals, in close proximity to one another, are connected by an electrolyte, ions migrate from the less noble metal. The "loser" is the anode, the more noble, or "winner" is the cathode.
In our case, aluminum is the anode (less noble). In fact it is one of the least noble metals, the only commons ones that are worse are zinc & magnesium, & it should dissolve quicker than a tin can. (I once witnessed the resurrection of a Japanese Zero, the wing spars were magnesium, & could be flaked away with your fingernail).
Interestingly, aluminum "rusts"(oxidizes)very, very quickly, so, why don't our masts & beams dissolve quicker than a common nail? The saving grace is that the result,(aluminum oxide) is a very good barrier.
Another major consideration, is the relative sizes of each piece of metal, also known as the ratio of Cathode to Anode (C/A). Many will remember the chemistry lab, where you covered a steel tray containing common salty foods with aluminum foil. The foil was pushed down onto the food with a pencil point, resulting in a few very small contact areas. This served to concentrate the electrical potential in a very small area. The foil was quickly eaten with "moth holes"at these points.
Consider the following two situations. Case A, an aluminum plate,(anode) containing an SS rivet. The rivet is more noble,(cathode), BUT it is very small in comparison to the aluminum plate, making for a small C/A. Corrosion will occur from the aluminum plate, but it will be slow, & this is what we use on our Cats, large aluminum extrusions, with small SS rivets. Incidentally, monel rivets possess the same potential as passive 304 SS.
Case B, an SS plate,(cathode) containing an aluminum rivet,(anode). In this case the C/A ratio is high, & corrosion of the the aluminum rivet will be severe, even though the electrical potential,(difference), was the same in both cases.
What lessons can we glean from all this?
Best, keep the parts out of an electrolytic substance, not possible in our case.
Better, eliminate areas where the C/A is high,(small aluminum in proximity to large SS).
Good, prevent the current from flowing between the dissimilar pieces, achieved with a barrier, ESPECIALLY WHERE THE CONTACT POINTS ARE CONCENTRATED.
This works well for the portion inside the compression tube, not so well where the rod exits the beam. The grease is quickly squished out of the way, & the contact point is concentrated against the thin wall of the beam. The problem is exacerbated by the use of the large SS washers directly against the aluminum beam. Some grease on the inside of the washers would help.
Take a close look at Philips photo, the worst corrosion is where the rod touches the beam walls. A cure could be had by enclosing the rod in a very thin plastic tube, but such a tube would not last long, the beams edges would soon cut through it.
Ultimately, what we are depending on is Case A, above. A large anode(beam) vs a relatively small cathode (rod).
In your case, the fresh water makes a much weaker electrolyte, hence less current, resulting in little or very slow corrosion. There are differences, depending on the pH value & hardness of the water, but it is much less than sea water. I personally have not greased my 5.7 in 4 years,(freshwater), I doubt if the PO ever did, & it shows zero effect,as can be seen from the album photos.
For those operating in corrosive environments, it would be an interesting experiment to utilize sacrificial anodic protection. A small zinc strip,(even better would be some magnesium wire) attached to both the rod & beam should work. It must be connected to both, then the zinc, being less noble than aluminum should become the anode. Someone should try it & report back.

Edited by Edchris177 on Jun 10, 2013 - 11:42 PM.