Stabilizer Installation

[drpohl]

I appreciate your preparation and plan but did you ask your previous surveyor for recommendations? Did you ask your insurance company regarding these major changes if they will require a re-survey and/or incline test/stability booklet by a NA? Whenever making major changes get it signed off from all the major players - before proceeding and after its done - sea trial and demonstrate to your and the surveyor's satisfaction.
Keep us advised on your progress and additional steps taken

[ASKAER]

Dear all Grand Banks folks out there!
What a wonderful and comprehensive sharing of observations and research on the stabilizer project at owner's own hand. I learned a lot. Currently I am having the very same work done on our 1year old GB 47 EU "ALMA" - hull #88 - read more about her at www.askaer.com. On recommendation by GB yard in Malaysia, I went for Trac 220 -6 with STAR using port engine as hydraulic pump PTO under way and electrical pump (generator on) during anchor, if needed. The procedure stated by you seems similar to mine and for the reasons of the many risks stated, and the fact that we keep the vessel in Singapore, we were grateful to GB that they offered to take the vessel back to the factory for the refit. It is currently at it's completion phase and next month we are going to try it all out. We are happy to report further at that time.
Super with this forum. All our best wishes and good luck.
Heine Askaer-Jensen
Singapore

[twistedtree]

Glad the hear from you , Heine.

For others on the forum, it's Heine's installation at the Grand Banks factory that I am shadowing, so I'm very grateful that he's one step ahead of me and that Grand Banks has so generously shared their plans.

[twistedtree]

Progress has been slow, but there is progress. My glass guy works 4 days a week in a high-end class car restoration shop, so I only get a couple hours in the evenings, Friday, and some portion of Saturday and Sunday. But the real challenge is the goo that GB uses to set the stringer/rib frame and bond it to the hull before tabbing everything in. It's too soft to grind out (it just gums up the abrasive), so he's chiseling it out in strips. It's working, but is very slow going. It took all day today to get it out, and I think he still has a bit more to do. Then the awlgrip needs to get ground off the rest of the area before the new layups go in.

The attached pictures show the port and starboard sides as of today.

One thing he's been working on in the evenings are the foam forms for the new stringers. The other picture shows them awaiting installation.

While all this has been going on, I continue to poke away at my electronics refit.

[twistedtree]

Here's some more progress. The pictures show the hull area ground clean and ready to have the new stringers added and the hull thickness built up.

The stringers are built around a foam core form which is epoxied in place before glassing over.

Next you can see one of the stringers with a first layer over it, then on the other side a layer over both the stringer and hull. There are two ore layups required to get to the 7/8" of additional hull thickness required.

Earlier this week another pallet of components arrived, and today I got the touch screen control panel installed in the lower helm. There also is a remote enable/disable control panel on the fly bridge which I installed, but didn't photograph yet. Stay tuned for that part.

I also spent some time with a helper today marking off the fin position on the hull, including it's fully deflected position in both directions. In the outboard position, the fin will hit a chine on the hull, so the fin needs to be notched to clear it. The measuring is so I can tell ABT how to make up the fins. I want to get them going since it will take 3 weeks or so to get them.

[twistedtree]

Progress continues, slow but steady. As mentioned earlier, I only get one full day per week out of my glass guy, plus another 1-2 days spread over evenings and weekends, so it goes slow. But the good news is that one side is done. I re-drilled the pilot hole and measured the thickness, and it's 1.5" - spot on what it should be. I love it when a plan comes together.

For me, this past weekend was templating time for the fins. My hull has an outer chine and the top rear of the fin needs to be notched to clear it when they are fully deflected outboard.

The first step was to measure everything out with the help of a friend. The centered fin position is parallel to the keel, so that's the first line we established. Next, we established two lines each at 45 deg off the center line representing the fully deflected positions. That gives us the center line of the fin in it's outboard position, and the interference quickly becomes apparent. But given the fin's width, the leading surface will hit first, so that's the controlling distance for the cut. So next we measured out a parallel line representing the leading surface of the fin, and used that for templating.

The first template I made with 2" foam insulation. Once I got the distance and angle right, I transferred it a small piece of plywood. See photos below. Once verified on both sides of the hull, off went the fin spec sheet to ABT for fabrication.

Now we are back to the waiting game. Once my glass guy is cleared out of the engine room, I'll confirm the actuator location, say three Hail Marys, and drill a 6" hole in the hull.

Oh, and I sorted out one lingering issue today - the reverse interlock. There's an input to the main control unit telling it when either transmission is in reverse so ti can center and lock the fins. The trick is linking it to the gear boxes somehow. ABT offers mechanical switches that can be used with mechanical shifters, but mine are electro-hydraulic. So the other option are pressure switches to detect when the hydraulic clutches are engaged. That's what I ordered, but I've been having trouble finding out what ports on my ZF hydraulics to attach the switches. Well, it turns out there is only one port, and it's pressurized when either clutch is engaged - but you can't distinguish which one. Problem.

Well, the solution isn't too bad - actually, it's pretty nice. My throttle and shift controls are made by Glendinning, and they offer an interface kit for just this sort of thing. It has cables that go in-line with the gear control cables, and provide breakout wires to a relay box. You can then wire into the relay box to tell the stabilizer control exactly what it needs to know. It's a very clean solution.

[twistedtree]

Today was Hail Mary day, and now my boat has a 6" hole in the hull. But before that....

There is a 16" diameter backing plate that mounts on the outside of the hull and is through-bolted through the inside mounting plate and actuator assembly, sandwiching the hull in between. Everything gets gooped up with 3M 5200 before final assembly. All this means that the anti fowling paint has to be removed when the outside plate will attach so the 5200 seals directly against the hull. The first pictures show the areas cleared of paint. I'll touch it up by hand before final assembly.

We also ran into a little problem. My glass guy was using the backing plate to be sure he maintained clearance between the stringers while building up the glass. It's a tight fit, and adding glass up the sides of the stringers could push it over the edge. Well, he didn't realize that the outside plate is about an inch smaller in diameter that the inside plate.

Darn. So he's had to do some grinding on the finished side, and has established a keep-out zone on the side still being glassed. The good news is that the inside plate now fits on the starboard side, which means it's time for drilling.

A 6" hole saw and a powerful right angle drill are a hazardous combination. Fortunately I've been beaten up by them before and know to proceed slowly and with caution. The pictures show my hull being threatened by the drill, then the final results.

Next you can see the inside mounting plate visible through the hole, and two screws that get placed to locate the plate in the hole. The screw heads just barely catch the edge of the plate, so I picked up some large ones on my way home today and will also relocate the holes so they firmly catch the plate edge .

The last picture shows the mounting plate from inside the hull. You can see three black bolts running through the plate. These are jack bolts used to precisely level the plate so it's exactly parallel to the hull's outside surface. ABT provides a very useful alignment tool to confirm the plates position, and I'll post picture later when I really put it to use. All I did today was make sure the plate position was in the right ball park, and it is.

Stay tuned......

[twistedtree]

Today was alignment day. There are three dimensions that need to be taken into consideration.

The first is the rotational position of the actuator assembly. You can spin it 360 deg to any orientation you like. I've got a forward bulkhead to deal with, and it has a finished panel that sticks out over the actuator. Installation and removal of the full actuator requires removing the panel, including all the equipment that will be mounted on it. Fortunately, it shouldn't need to be removed except in extreme circumstances. For normal maintenance and repair it stays in place. However, the hydraulic cylinder, locking cylinder and pin, and top mounting late all need to be removable for periodic maintenance and repair. They need to be removable with the bulkhead in place. The trick is to rotate the actuator assembly so none of these parts are blocked by the trim panel.

Normally you do this my temporarily installing the actuator, but man is that thing heavy, and I don't want to risk damaging it or smashing into something else in the boat. So I made a template. I printed a 1:1 scale drawing of the actuator, cut it out, then pinned it to a piece of plywood. I traced the outline, then cut the plywood template. With the plywood template in hand, I pinned the drawing back on and drilled the mounting holes and places bolts into three of the holes to locate it.

In the first picture, you can see the template and cartoon actuator sitting on top of the castle mounting plate. With it, I was able to easily play with different rotational positions of the actuators, and using another scrap of plywood in place of the bulkhead trim panel, confirm that all the removable parts would clear the bulkhead. I was also able to confirm access to bolts and clearance for hydraulic hoses. Speaking of which, I'll need to move the hose ports to the opposite side on the locking pin cylinder, otherwise they would hit the bulkhead. There are ports on both sides, so I just need to swap the fittings and plugs.

The next trick is to be sure the actuator can be installed and removed, and this posed a problem. In the picture you can see the vertical that the bulkhead trim panel fastens to, and you can see that when lifting the actuator straight up would crash into the brace. The black line is where it will need to be cut back for clearance. Once the actuator is up that high, it can be tipped sideways and pulled out.

Once all this rotational positioning is done, the hull and plate are marked. The next alignment is to get the plate positioned fore/aft, and port/starboard so the shaft in centered in the correct location. This is especially important in my case since my fins are being trimmed to clear the outer hull chine, and that cut is based on a presumed shaft location. If that location moves, it could cause the fins to hit the chine. That would not make for a happy day.

Establishing this location is pretty easy. In the last post I showed the locator screws that go horizontally into the drill hole and provide a surface for the flange to rest against. I got bigger screws and put them in a better position, and now they catch the flange just fine, as shown in the next picture. They can be adjusted in/out to shift the flange around. I got luck and they lined up fine first try. The alignment tool is used to confirm the center location.

You can see the alignment tool in the 4th picture. It's a cylinder that fits in the mounting plate bore, and has an angle iron screwed to it and cut to the length of the fin. To confirm the shaft center, you just check that the bar lines up with the fin center line and 45 deg deflection lines previously drawn on the hull. Sure enough, they do.

The last dimension of alignment is to get the shaft exactly perpendicular with the hull. This is critical to ensure that the ends of the fin maintain proper clearance from the hull throughout their swing range and especially that they don't bind up against the hull. This alignment is accomplished using the three jacking bolts on the mounting plate. By adjusting them up and down, the plane of the plate shifts, and using the alignment tool you can tell when clearance is equal throughout the swing range. The last pictures show the tool in the centered and two extreme positions.

Now the starboard side is ready for potting, but I think we'll get the port side ready and do them both at the same time.

[twistedtree]

I see lots of views of this thread, but not many comments. I hope everyone finds it useful. Or are you all speechless over the horror that I'm committing?

[dacust]

Originally Posted by twistedtree

I see lots of views of this thread, but not many comments. I hope everyone finds it useful. Or are you all speechless over the horror that I'm committing?

I'm fascinated. I'm forwarding this a friend of mine.

See ==> Custom BowSprit
where we drilled holes in his boat.

I could see ending up in the same situation you have. Having seen what you are doing would lessen my fears.

Also, your posts are thorough, and explain well, so it'd be a shame to clutter it up with a lot of chatter. I'm betting all the comments will come at the end.

Carry on, Sir!

-dan

[jkleins]

I agree. Not much to say since you are doing all the work but your descriptions are very much appreciated.

Jim

[u4ea32]

Thanks, twistedtree, for providing this detailed information on your project. Its very interesting. Looks like you are doing all the right stuff right.

I think you did the right thing by going with larger fins. And I think you did the right thing by doing the project yourself, as those install quotes seem absurd to me too.

I know very little about stabilizers, having only used them but never installed them. However, one thing I did learn is that they work hard, and that work requires a lot of cooling. On a hard chine boat like a GB, they work very hard. In warm water such as the southern gulf stream, stabilizers can have a hard time staying cool enough. So, as in most cases of heat exchangers, I suggest you increase the cooler size over the factory recommendation.

[twistedtree]

Originally Posted by u4ea32

I know very little about stabilizers, having only used them but never installed them. However, one thing I did learn is that they work hard, and that work requires a lot of cooling. On a hard chine boat like a GB, they work very hard. In warm water such as the southern gulf stream, stabilizers can have a hard time staying cool enough. So, as in most cases of heat exchangers, I suggest you increase the cooler size over the factory recommendation.

First, thanks for the comments.

I agree on the cooling. ABT wants 90 deg max water temp for cooling. In New England we are lucky if the water hits 70, but we plan to travel south at times where 80-85 deg water is likely. I get about 10 deg rise across my engines, so that means I need to grab water on the inlet side of the engines, not the outlet side. ABT normally supplies a cooler with a 2" raw water inlet/outlet, but my intake line is 2.5" so I upgraded to a 3" cooler. That also adds less inlet restriction to ensure I don't starve the main engines. I'll measure it once operational, but the calculations say I'll be well below Cummins' spec. The control panel has temp alarms, and there is a thermometer on the reservoir tank, so I'll be able to keep an eye on it.

[twistedtree]

Here's another brief installment. While waiting on the remaining glass work, I decided to start installing some of the control equipment, and to start putting the bulkhead back together.

The first picture is of the main control unit. It needs to be mounted vertically and athwart-ships, presumably because it houses various motion and roll sensors. The Gledinning control box is next to it, and had to be moved 3"-4" to the right to make room, but everything fits nicely.

The next picture shows one of the bulkhead panels back in place, with my autopilot and depth finder added next to the galvanic isolators. Another snug fit, but it works. None of this relates to the stabilizers, other than to give context as the bulkhead takes shape. Which leads us to the next picture.

Next is the panel that goes above the last panel. I've been laying it out in the cockpit on some sawhorses. The copper colored box is a 12V to 24V power converter. The stabilizers operate off 24V, so this step up converter is required given my 12V boat system. The remaining space will be a NEMA 2000 junction point, and a combiner point for on-board TV cabling. All the TV stuff was crammed behind the bulkhead before, inaccessible and unlabeled.

The last picture shows the next bulkhead panel moving outboard on the starboard side. Once again, it's up on my sawhorses for layout of the various components. The reservoir tank is obvious with its attached oil filter and back-pressure gauge for the return oil line. Hopefully you can see the tracing lines on the panel for the other parts. Hanging off the bottom of the tank is a shutoff valve for the pump suction line. Over to the right of the tank is a square trace where the starboard servo valve assembly will mount. The tank is heavy, even when empty - I'd estimate 40-50 lbs - so I plan to add some reinforcement on the back side. I haven't sorted out exactly what, but have a few ideas kicking around.

I don't have any pictures, but the PTO adapter that's used to couple the hydraulic pump to the ZF transmission came unpainted, so I took it home last night and brushed on a couple of coats of engine paint. Thankfully, the boat come with a small can.

[twistedtree]

Glass work continues to crawl along, but I don't want to rush it. On the starboard side we ended up with a bit of a bowl in the glass that would take 3/4" of epoxy filler under the mounting plate. We are concerned about mixing a large quantity of filler and the risk of expansion which would really screw things up. So we decided to add more glass in the center to bring it up. That's done and I realigned to plate. Now we are down to 3/8" to 1/2" to fill. Much better.

On the port side, I drilled the 6" hole and test fit the plate. In doing so, I found that side needs to be thickened up a bit too. That was done today, and I'll drill out the new layers tomorrow to see where we stand. I think Sunday or Monday we'll try potting one side and see how it goes.

While waiting for the new glass to cure, I decided to install the PTO kit and hydraulic pump on my starboard transmission.The first picture shows the cover plate where the PTO adapter goes. That plate comes off, and there is a disk-like plug behind it seals in the oil. The blue oil line attaches to the transmission oil pump. This becomes a problem later on....

The next picture shows the plate removed, mounting studs installed, and the drive coupler installed.

Next shows the adapter and pump mounted up. The adapter accepts 4-bolt and 2-bolt pumps, and as you can see mine is 2-bolt. That's why you can see an empty hole and part of the gasket showing.

Between this and the last picture, you can see a little problem that cropped up. In the lower left you can see where I disconnected the oil hose from the trans pump to make room for the PTO installation. But now the PTO and pump assembly are in the way and prevent re-attachment of the hose. I was hoping I could unbolt the pump, rotate it a bit, then bolt it back on, but no-go on that. The mount bolts only align one way.

It looks like the best solution will be to re-route the hose so it comes in from the side rather than the top, and replace the end with a right angle fitting. Fortunately the new route is shorted, so it should all work. So it's off to the hose shop tomorrow AM.