Chainplate Inspection [Master Thread]

[Loren Beach]

Note that for our boat I buffed the stern plate to a mirror finish when it was off the boat. Same for deck shroud connectors and the more-complicated bow fitting. This made inspection easy and should stave off surface corrosion for lots of years. Hopefully.
Thanks again for great postings with pictures, and such helpful narrative!
Also noted: I have a lot of pure dumb luck in that the shroud fitting with its Navtec below-deck rod is easier to get at on the O-34 model. Also luck that I never have had to withdraw either rod from the large aluminum round bar a the bottom...

 

[Nick J]

After working on replacement blocks for a few months, I finally received my order from ProtoLabs last night. The blocks look perfect! They’re made out of 7075 T6 Aluminum with a hard anodized finish. All said and done, it was $830 for all 6 blocks. In comparison, I’ve heard Rig Rite charges $400-$500 per block but they didn’t respond to any of my emails or phone calls, so I couldn’t confirm that cost. The lowest local quote I received was $1,800 and they recommended I went the online route.

New Blocks


The most difficult part was reverse engineering the tie rod sockets. There’s an excellent post on Cruisers Forum from a Niagra owner (https://www.cruisersforum.com/forums/f116/navtec-tie-rod-block-material-284414.html). The post goes over material and the design process including using a 3D printer to verify fit. I exchanged some messages with the original poster and he provided his CAD files. Unfortunately, the design didn’t work for me, but the thread provided extremely valuable information and a great example on how to get it done. One of the most valuable pieces of advice was to print half a test block so you can see the contact point between the stem ball and the socket. Once I got close, I printed a full block, coated the tie rod with graphite from a pencil, seated the rod, and spun it to mark the contact point. The Hayn geometry made good contact halfway between the OD of the socket and the ID of the rod exit hole. Most of the other models I tested only contacted the block at the edge of the exit hole or the edge of the head. Contacting in the middle allowed for more articulation while still having a good amount of material supporting the head.

Once the socket geometry was finalized, I tweaked the depth of the socket, counter bore depth, and counter bore diameter. Rasing the socket depth so the top of the head just cleared the top of the block ensured I had the maximum amount of material under the socket. Decreasing the counter bore depth had the same effect, but in the opposite direction. Widening the counterbore diameter allowed a standard socket to fit between the nut and wall of the counter bore. I don’t think any of these changes were necessary, but if your designing a custom block, why not make it better?

Some of the prototypes with the original blocks and new u bolts

failed sockets, all to small creating a contact point on the very edge of the rod exit hole


Protype on the 3D printer

Final Geometry with central contact point (Hayn geometry)


Enlarged counter bore for socket clearance:



So, was this all necessary? Probably not. More than one machine shop inspected the corroded blocks and 4 U-bolts that didn’t fit and advised me to just widen out the holes, sand off the corrosion, and stick everything back in the boat. That probably would have been more than adequate, but after going through all the work to disassemble the chain plate assembly, order new U bolts, and replace the standing rigging, I didn’t feel right reusing the old blocks. I also have a degree in manufacturing engineering, but never actually used it since I went into telecom. This project gave me an opportunity to work on something I really enjoy. Seeing a project go from “wouldn’t it be nice” or “If I designed it, I would change…” to an actual product is something special, at least it is for me.

This effort also may provide assistance to anyone else in the same or worse situation who doesn’t have the resources to get a replacement part made. I should be able to take my existing models and adjust the socket angle as needed and get the part made through ProtoLab, Xometry, or any other manufacturing resource.

 

[Kenneth K]

Impressive work!

How much you want for the little green tug?

 

[mbowser]

Nice work, they look great. Enlarging the counter bore to fit a standard socket is a great addition, I didn't do that on my Niagara (didn't think of it until I started installing the finished blocks). Fortunately, the counter bore is shallow enough that there is just enough 'meat' on a high profile nut to get a socket on and tighten it down.

 

[Nick J]

Impressive work!

How much you want for the little green tug?
View attachment 52844

Ha! My son showed me that as soon as the 3d printer arrived. It's called a benchy, short for benchmark. It's a model designed to show a 3d printer's capabilities.

 

[Nick J]

All the tie rods, backing plates, and port U-bolts are back in the boat. I’m waiting for the starboard tie rod hole epoxy filler to cure before installing the starboard side. It was an absolute struggle, but almost all the problems were self-imposed. I hope I never have to do this again on this boat, so hopefully others can learn from my mistakes:

• A lot of my issues on this project have stemmed from not inspecting the U-bolts first. I thought I would be efficient and order replacements from Garhauer before pulling everything apart so they were in-hand when I was doing the actual work. All hopes for an efficient process are out the window. The measurements on Rig Rites site are not correct. They say the U-bolts are 2 1/8 wide and I thought I confirmed that when I measured. They’re actually closer to 2 1/16. That little difference made the U-bolt not fit the original aluminum backing plate. I also wasn’t sure about the length of the U-bolt, so I ordered them long which requires cutting 3/8” off each leg. It’s not the end of the world, but it does add about 20 minutes to each U-bolt. I’m still happy I replaced the U-Bolts and backing plates, but it would have been better if I just sent the original U-bolts to Garhauer like they asked me to do from the start.
• Don’t expect a ½” bolt to fit in a ½” hole. If it was just a single bolt, a ½” hole would have been fine, but 2 x ½” holes spaced at a specific distance apart plus the variance between U-bolts made it almost impossible to seat the them in the deck. Once I widened the holes to 17/32 the bolts fit easily without too much play. I should have figured this out ahead of time, because that’s what I ended up doing on the aluminum backing plates.
• Drill the hole in the deck!!! I spent way too much time trying to extract, then install the long starboard tie rods around the cabinetry. The amount of effort I spent removing trim and backing blocks, cutting plywood, and fighting the bent tie rods to avoid drilling the holes in the deck was completely wasted. I ended up having to drill the holes anyway when I put them back in. It was impossible to align the treads. At the end of the day, drilling the holes in the deck was one of the easiest parts of the project and I could have saved a ton of work if I just did it from the start. I reduced the number of holes to fill by enlarging one of the U-bolt holes to fit the tie rod through the deck.

• Don’t assume anything is straight, plumb, or perpendicular on a boat. I thought the tie rods would be perpendicular to the aluminum slugs and would thread in perfectly once I installed them through the hole in the deck. Two of them were close enough to easily engage the threads, but the aft lower rod was off by enough to start cross threading the threads. After an hour of struggling, I figured out I needed to raise the outboard end of the slug and lower the inboard end to align it properly. I put a string through the tie rod hole and around the slug to raise it while wedging a screw driver on the other end. Once this was in place, the rod engaged the threads perfectly.

• Use thread lube! This one hurts because I’m probably going to need Garhauer to make another U-bolt. I was rushing and forgot to put Lanocote on the threads of the U-bolt, then I made it worse by using my drill to speed up threading the nut on. I should have figured it out when the clutch on the drill clicked, but I pressed on and moved the clutch to drill mode. By the time the drill torqued, it was too late. The nut had heated up and galled. It took about 15 minutes of slow work with a socket wrench to get the nut off so I could remove the U-bolt. Garhauer shipped the U-bolts with some kind of thread lubricant (I think it was TefGel), but I had to cut that section off to shorten them. I’m going to try to clean up the threads tonight, but it isn’t looking good. Thankfully, Garhauer is quick, so this shouldn’t hold up the project.
• Verify fit before disassembly. The aluminum tie rod blocks came from Navtec in various angles, both side to side and fore and aft. The angles are stamped on the top of the blocks and I assumed they were correct. However, if you’re going to make custom blocks, you might as well measure the actual angle before disassembly. There’s no need to stick to standard angles manufactured 40 years ago when you have the real-world application right in front of you. All but one of the blocks fit well, but the aft lower on the Port side looks off by several degrees requiring a fair amount of bend in the rod to attach it to the SS chain plate. If I remember correctly, the original block had the same issue, but I didn’t think anything of it at the time. The bend in the SS chain plate is also off by several degrees. I’m going to measure the angle tonight and see how far off it is before figuring out what to do. This is another difficult one to swallow, because it’s going to cost a fair bit of time and money to fix. It all could have been avoided by using the 3D test blocks to verify the angle before sending them out for machining.
• Don’t rely on memory. I mixed up the port lower tie rods and didn’t figure it out until I had them both in place. The forward lower turnbuckle was completely bottomed out, but the pin hole was still 1/16” or so away from lining up. And the aft lower was barely threaded into the turnbuckle. Swapping them left both turnbuckles about 50% open, which is perfect. That mistake took about 1.5 hours to resolve due to the tight working space in the head. Marking everything form the beginning would have avoided this issue entirely.
• Bring more than 1 battery. I’m heavily invested in the Makita platform with over a dozen batteries, and I remembered to bring every tool I could possibly need, but I only 1 battery. I even had multiple drills so I could have the drill for the hole and a drill for a chamfer bit ready to go. Each U bolt required at least 4 tools to install (multitool to sand the bed flat, drill for the hole and chamfer, grinder to shorten the U-bolt, and vacuum to clean everything up) I must have spent an extra hour just moving the battery from one tool to another.

One idea that actually helped out was a 3D printed drill guide. The part was designed using the same file and sketch as the backing block. This eliminated any guess work and measuring when drilling the deck holes. Everyone was perfectly spaced and lined up with the backing block. At least one thing worked out.

 

[southofvictor]

Thanks for the excellent write-up of your experience Nick! A lot of great advice in there.

 

[Prairie Schooner]

. . . It was an absolute struggle, but almost all the problems were self-imposed. I hope I never have to do this again on this boat, so hopefully others can learn from my mistakes:

I identify with this so much, Nick. My downfall is overthinking and over-engineering projects, as well as fussing too much about aesthetics. In almost every one of my boat projects I see the parts that didn't turn out as well as I'd envisioned. I'm probably feeling it more acutely now as I'm in the final death march preparing to launch. It's a different rhythm for those of us who need to haul every winter. Perhaps a benefit is dividing the year more neatly into work time and play time. If your boat's in the water all year I can see where they'd slur together.

Great write-up. It's rewarding to join in the work vicariously as I read along. Good luck wrapping things up.

 

[Nick J]

Thanks! Even though we don't haul out every year, I still try to do the big project between November and March. That usually goes into April and this one's bleeding into June. The family is getting restless and wants to get back out on the water. We're actually taking a trip this weekend without the mast and fully prepared to hear all about it at each anchorage. All that said, I'm still enjoying the project. I knew the rig needed work when we purchased the boat and I used to get nervous every time the wind was over 10 knots. I know that's not fulling going to go away, but knowing every inch of the rig should ease those nerves a bit.

I ended up ordering a new U-bolt form Garhauer. They had one in stock and ready to ship, so no delays! I can't say enough good things about them. They are always eager to help and their products are top notch. Mike was kind and didn't give me too much grief when I told him I needed a new one because I screwed up.

 

[Nick J]

Here's an example of one of the many difficulties faced when working on these chainplates. To get a full turn on the tie rod, I had to position the wrench 4 different directions and the flat spot is almost flush with the cabinetry. The design is great for interior space and seems robust, but man is it a pain in the butt to work on.

 

[Kenneth K]

Have you tried crowfoot wrenches? I don't have a set, but every other time I do a boat project, I think about buying one.

 

[Nick J]

Not a bad idea, I wonder if that would have been easier. The tie rods are kind of weird. They don't seem to be machined to a standard wrench size, so an adjustable wrench works best. Disassembly was extremely difficult and put a lot of stress on the wrench. When I had them out of the boat, I cleaned the threads with a tap and die set. It's way easer to turn now, but there's still have the awkwardness of needing to reposition the wrench every quarter turn.

On a somewhat related front, the spars are out of the paint shop!

 

[G Kiba]

This is a continuation of the conversation started on the rigging cost estimate thread here: https://ericsonyachts.org/ie/threads/standing-rigging-estimates.21767/

On our 35-3, the port chain plate rods terminate on Navtec open body toggle turnbuckles that pin to standard chain plates bolted to the settee back and main bulkhead. I removed, inspected, polished and reinstalled these a few years ago when I had access during my head rebuilt project (https://ericsonyachts.org/ie/threads/35-3-port-chainplate-pics-disassembly-issue.18292/ ). These were easy to remove as long as the turn buckles turned. When I first pulled the, I needed heat and penetrating oil, but I put them back together with Lanocote, so they turned easily when I pulled them for the rerig.

The starboard chain plate rods terminate in 1 ½” aluminum slugs sitting in the TAFG. The rods pass through two pieces of plywood before extending up to the bottom of the side deck where they meet with the aluminum chain plate blocks. The first problem was the threads between the nitronic 50 rods and the aluminum slugs. It took a 12” pipe wrench and CRC Freeze off penetrating oil to get these to budge. The main cap / intermediate rod fought me the whole way. It felt like 42,000 turns to get it out all done in ½ turns to reposition the wrench.

Once I got the threads to turn, the next problem was getting the rod out from under the deck. This required removing the teak trim, cutting the backing block and notching out the piece of sidewall plywood under the trim. At that point, it was an interference fit with the head scraping the side wall and even butting up against the portlight. There was enough flex in the rod to bend it out. I don’t think I’m going to be able to reinstall them the same way I pulled them. Having the bed the rod while lining up the threads seems next to impossible, so I will probably have to drill a hole in the deck after all and install from above. The forward lower rod was much more willing to come out and turned freely with only a quick squirt of penetrating oil. The lower aft rod seems to turn well, but I was too tired to tackle it last night. I'll take care of the that one later this week.

The flat spots on the main rod was not strong enough to hold a wrench and I came too close to rounding it off. The pipe wrench I used put some pretty deep gouges in the rod. I’m going to take the to my rigger and probably a machine shop to get a second opinion on the need to replace them before reinstallation.

Compared to the tie rods, the backstay chain plate was simple to remove. Just 6 bolts and it popped off. There was enough sealant in the holes to hold the bolts while I removed the nuts so I didn’t need someone on the outside with a screwdriver. There was very little sealant between the chain plate and the hull and I was surprised to find white gel coat instead of the flag blue hull color we’re used to. I had always thought the boat was blue from the factory, but I think this means the paint was something that came a little later in the boat’s life.

The chain plate looked good at first glance, but after cleaning it up and inspecting closer, I found some cracks around the 4th hole from the top. The cracks are very small, but one does look to go through to the edged of the chain plate. The weird thing to me is it’s not the first or second hole. Again, I’ll get a second opinion this week, but I’m pretty sure it needs to be replaced.

top of cap / int. rod showing interference with the plywood and port light and the notch:
View attachment 52246

First plywood the rod goes through:
View attachment 52247

Second plywood and hole to where the aluminum slog goes:
View attachment 52248

full path:
View attachment 52249

removed chain plate rods:
View attachment 52254

Backstay chain plate with crack:
View attachment 52253

View attachment 52256View attachment 52257

This is a continuation of the conversation started on the rigging cost estimate thread here: https://ericsonyachts.org/ie/threads/standing-rigging-estimates.21767/

On our 35-3, the port chain plate rods terminate on Navtec open body toggle turnbuckles that pin to standard chain plates bolted to the settee back and main bulkhead. I removed, inspected, polished and reinstalled these a few years ago when I had access during my head rebuilt project (https://ericsonyachts.org/ie/threads/35-3-port-chainplate-pics-disassembly-issue.18292/ ). These were easy to remove as long as the turn buckles turned. When I first pulled the, I needed heat and penetrating oil, but I put them back together with Lanocote, so they turned easily when I pulled them for the rerig.

The starboard chain plate rods terminate in 1 ½” aluminum slugs sitting in the TAFG. The rods pass through two pieces of plywood before extending up to the bottom of the side deck where they meet with the aluminum chain plate blocks. The first problem was the threads between the nitronic 50 rods and the aluminum slugs. It took a 12” pipe wrench and CRC Freeze off penetrating oil to get these to budge. The main cap / intermediate rod fought me the whole way. It felt like 42,000 turns to get it out all done in ½ turns to reposition the wrench.

Once I got the threads to turn, the next problem was getting the rod out from under the deck. This required removing the teak trim, cutting the backing block and notching out the piece of sidewall plywood under the trim. At that point, it was an interference fit with the head scraping the side wall and even butting up against the portlight. There was enough flex in the rod to bend it out. I don’t think I’m going to be able to reinstall them the same way I pulled them. Having the bed the rod while lining up the threads seems next to impossible, so I will probably have to drill a hole in the deck after all and install from above. The forward lower rod was much more willing to come out and turned freely with only a quick squirt of penetrating oil. The lower aft rod seems to turn well, but I was too tired to tackle it last night. I'll take care of the that one later this week.

The flat spots on the main rod was not strong enough to hold a wrench and I came too close to rounding it off. The pipe wrench I used put some pretty deep gouges in the rod. I’m going to take the to my rigger and probably a machine shop to get a second opinion on the need to replace them before reinstallation.

Compared to the tie rods, the backstay chain plate was simple to remove. Just 6 bolts and it popped off. There was enough sealant in the holes to hold the bolts while I removed the nuts so I didn’t need someone on the outside with a screwdriver. There was very little sealant between the chain plate and the hull and I was surprised to find white gel coat instead of the flag blue hull color we’re used to. I had always thought the boat was blue from the factory, but I think this means the paint was something that came a little later in the boat’s life.

The chain plate looked good at first glance, but after cleaning it up and inspecting closer, I found some cracks around the 4th hole from the top. The cracks are very small, but one does look to go through to the edged of the chain plate. The weird thing to me is it’s not the first or second hole. Again, I’ll get a second opinion this week, but I’m pretty sure it needs to be replaced.

top of cap / int. rod showing interference with the plywood and port light and the notch:
View attachment 52246

First plywood the rod goes through:
View attachment 52247

Second plywood and hole to where the aluminum slog goes:
View attachment 52248

full path:
View attachment 52249

removed chain plate rods:
View attachment 52254

Backstay chain plate with crack:
View attachment 52253

View attachment 52256View attachment 52257

Nick, Great post as I am now experiencing some noise from the tie rods. Curious if you experienced any noises from the tie roods while sailing or if your project was preventive maintenance? Also wondering how tight the rods should be on re-assembly?

 

[Nick J]

I don't remember any noises from the chain plates or tie rods before the project. My work was somewhere between maintenance and repair. It was solid, but the starboard cap and intermediate tie rod was lifting to the point that the gelcoat was cracked and I wasn't able to turn the tie rods. I also had some rust staining under a few of the u bolts. Between the rust stains and cracked gel coat, I thought it would be good to address it while the rig was off the boat.

I'm not sure about Olson specific models, but the rig tune info on the 35-3 called for tightening the tie rod to engage the head in the cup then add 1 additional turn. I did that on my install and it seemed to work well. I repaired the crack in the gel coat and it hasn't reopened. I've also verified that the deck isn't lifting by placing a 4' level on the deck and sighting down the bottom edge for any gaps. Cleaning up the threads on the tie rods and aluminum slugs they thread into and using Lanocote or TefGel on all mating surfaces significantly helped with the ability to turn the rods.

 

[ConchyDug]

Harbor Freight crowsfeet are really great at splaying open and slipping off allowing you to punch the nearest metal object. Crowsfeet are such a niche tool they are hardly worth buying for a hobbyist. Use a 4 way wrench, as the name implies you get 4 non-right angles on the open end for flexibility and they are super handy.


Are the tie rods making popping/creaking sounds? Like Nick said use the straight edge method on the deck to determine how tight to go on the tie rods. I'd lay eyes and a wrench on the chain plate bolts as well and make sure they are not spinning. I've had chain plates on a Henderson 30 make creaking/popping sounds, after inspecting the bolts were not tightened up with some even spinning freely.

 

[Nick J]

Those look like they could be helpful, but as noted above, my tie rods weren't milled to a standard wrench size. Using an adjustable wrench was necessary to reduce the chance of rounding off the edges. On one one of the rods, I used a pipe wrench then cleaned up the marks it left. Not ideal, but it was the only way I found to get the assembly to budge.

 

[G Kiba]

I don't remember any noises from the chain plates or tie rods before the project. My work was somewhere between maintenance and repair. It was solid, but the starboard cap and intermediate tie rod was lifting to the point that the gelcoat was cracked and I wasn't able to turn the tie rods. I also had some rust staining under a few of the u bolts. Between the rust stains and cracked gel coat, I thought it would be good to address it while the rig was off the boat.

I'm not sure about Olson specific models, but the rig tune info on the 35-3 called for tightening the tie rod to engage the head in the cup then add 1 additional turn. I did that on my install and it seemed to work well. I repaired the crack in the gel coat and it hasn't reopened. I've also verified that the deck isn't lifting by placing a 4' level on the deck and sighting down the bottom edge for any gaps. Cleaning up the threads on the tie rods and aluminum slugs they thread into and using Lanocote or TefGel on all mating surfaces significantly helped with the ability to turn the rods.

Great info. Thanks Nick