[Creager]

Sailho, How did you jack up your mast. Did the loose turnbuckles give you any trouble with the mast not being stable?

 

[510datsun]

Re: Compression post repaired

Sailho, How did you jack up your mast. Did the loose turnbuckles give you any trouble with the mast not being stable?

I kinda covered how I jacked up the cabin top, mast, from my whole experience with this fix, you really need to de-mast the boat. To fix the counter top sag, you need to completely remove the metal compression post, the mast wires run through the post, making it near impossible to remove with the mast wires connected.

Safety, convince, and easier to work on the repair with the mast removed goes a long way with this repair. This can be a costly repair if done by a contractor or boat yard. You save plenty by doing it yourself, spend some of the saving, its well worth it, on de-masting the boat.

The repair will take you 4 or more days to complete, long time to suspend the mast of the compression post. Most experienced riggers can bring down the mast with the boat still at the dock with or without a crane.

Oh, one of my chain plate bulk heads, the forward port one, was completely rotten from the chain plate leaking, a previous owner used silicone. If you have chain plates that have been leaking, a good probability, and your shrouds could fail. My bulk head looked fine until I removed the chain plate. I was able to fix because safely because the mast was down. Another point for de-masting.

Good Luck whichever way you go.

 

[510datsun]

Re: Compression post repaired

Thank You for your positive comments on my fix post. I was hoping the effort was worth it to the Islander 28 community.

I do wish I had taken pictures of how I did the cabin top jack up part. I was pretty busy at the time and not really wanting to snap pictures.

Thanks All!

 

[Creager]

Sailho, thanks for the info. You confrimed my thoughts on de masting because I didn't know how long the fix woud take. I appreciate the feedback.

 

[510datsun]

Sailho, thanks for the info. You confrimed my thoughts on de masting because I didn't know how long the fix woud take. I appreciate the feedback.

Ah, I was the one who gave you the advice not Sailho, sorry Sailho, at least I think I was. I'm 510datsun, I posted up how I fixed the compression post with plenty of pictures, just didn't have the jack up pictures.

I just took some pictures on how I jacked up my cabin top, but my mast was off. I will post them tomorrow night or Monday.
I took the metal post out because it was driving me nuts thinking about having to fish the mast wires through the small holes then the tube itself. I'm going to drill the holes out to 1 3/8 and put in 1 inch PVC pipe, wires will pass through easy with no hanging up.

 

[510datsun]

Sailho, How did you jack up your mast. Did the loose turnbuckles give you any trouble with the mast not being stable?

I have finally gotten some time to post up pictures of when I jacked up the cabin top to do the repair on the compression post on my Islander 28.

I had my mast down for my repairs, but could be done with the mast up if done properly. The mast and spreaders weight about 125 pounds, not as heavy as you think, just tall and awkward. The foot plate the mast sets on has a 1/4-3/8 inch lip the mast extrusion fits over. This will keep the mast from slipping out from under the rigging should the rigging become loose for whatever reason. Keep in mind that is not much margin for loose rigging.

At your own risk you can gradually loosen the rigging slightly, jack up a little, check the rigging, loosen slightly, jack up slightly, and so on, until you can remove the post. Reverse after repairs
The mast only weights about 120 pounds. I would still run lines from the spreaders to the rails port, starboard, forward and aft. I would have these lines fairly relaxed. I would remove all sails and the boom.

The biggest problem is if you want to replace the counter top the metal tub sets on. You have to remove the tube completely and place a temporary 2x4 or 4x4 the correct length to support the cabin top and be able to move the jack set up. This allows you to fix it all. The bear is getting the tube out with the wires running through it. I re-stepped my mast with all new wiring too.

I even drilled each end out to be the same size on the tube. Then put in a PVC tube through the holes and glued them in. Sure made it easier to fish the wiring through the tube. Imagine a pipe with 1/4 wall and to plates welded on each end, the only 1 inch holes in the plate. You put the wire in and it hits the plate at the bottom.

Any way you can fix the weakest part of the compression post, the floor area, without much hassle. Just requires right tools and time.

here are my pictures of how I jacked up my cabin top. Remember, shouldn't have to much load on the jack if the mast is removed. You can hear when you are getting close to original height, head bulkhead will creek some where it is tabbed.

Keep an eye on the set up and boards getting out of alignment. You don't want them kicking out from under the jack. I put a piece of 3/4 plywood along the sauté and a 2x4 to keep the jack up right to accommodate the lateral force. It doesn't take much to move the top.

Jack from my Toyota or a bottle jack


Side bracing. You will need some wood door type shims for leveling the 2x4 on the sole, shown on the top right corner of the 2x4.


Jack in place with 2x4 to cabin top. I had to use some additional 2x4 under the jack to get the correct height and have travel in the jack.


Cabin top area


Once the top is at the height you want measure the distance from the top to the 2x4 next to the jack base. Cut a 2x4 length and put it next to the jack set up, using shims to adjust fit. Then remove the jack set up. You could put in a few screw attaching the 2x4 to the floor 2x4's and the 3/4 inch plywood at the top, prior to removing the jack of course.
This worked for me, there maybe better ways, but this seemed pretty easy.

Good Luck and work safely!

 

[hellosailor]

FWIW-
You can also rent a "lally column jack" cheaply at many hardware stores. That's the tall steel screw jack you often see holding up beams in basements. The advantage is that you don't have to worry about the end of a 2x4 slipping off the jack, since it is one very tall steel column.
FWIW.

 

[510datsun]

FWIW-
You can also rent a "lally column jack" cheaply at many hardware stores. That's the tall steel screw jack you often see holding up beams in basements. The advantage is that you don't have to worry about the end of a 2x4 slipping off the jack, since it is one very tall steel column.
FWIW.

That's an option too. Not sure if they would work 100 percent using just one jack. The Jack needs to be placed off to the side of the area you need to cutout at the floor under the compression post. So, you will have an X and Y component on the jack.

Sole area cutout I did for my 10x24x3/4 aluminum plate, black in the picture.

You may be able to use two jacks, as you described, a long piece of 3/4 inch plywood, and a 2x4 place across the cabin top. I would angle the top plywood and 2x4 about 30 degrees to the post, or angle it to go just next to the post. One end towards the starboard Sautee and the other to port by the by the head door. Then put the jacks at each end of the 2x4 supporting the 3/4 plywood on the cabin top. I would use some plywood under the jack bases on the sole too. The plywood and 2x4 would even out the load on the cabin top. You would have the jack bases out of the way on the sole and move the top up with more evenly distributed load. The load shouldn't be more then 300# divided by 2, 150 at both ends, and insure you don't damage the fiberglass top. This method would eliminate the lateral component, the jacks would be straight up and down.

If you are just fixing the floor section, leave the post bolted to the counter top. You will be able to pull the whole compression post, counter and post at the sole.
I fixed the counter top first with pole removed. Then bolted the post back up and jacked up the top again raising the post at the floor. Then fixed the sole area.

Thanks for the suggestion

 

[downeast450]

510,

Well done! Thanks for the suggestion of the PVC sleeve inside the post. I am doing some work that will involve my mast step and the compression post. New wire routing for the mast, too. A sleeve makes good sense.

Down

 

[510datsun]

510,

Well done! Thanks for the suggestion of the PVC sleeve inside the post. I am doing some work that will involve my mast step and the compression post. New wire routing for the mast, too. A sleeve makes good sense.

Down

I replaced the mast foot, all new wires and lights. I think I used a 1 1/2 diameter PVC pipe, drilled both ends the OD of the tube, and silicone it in. Once in place the PVC tube will be supported by the top and counter. I found it easier to have both ends the OD to make it easier to secure the tube to the post.

The mast wires go through the cabin top at an odd angle to get to the top post hole. Before you put the mast foot back, make sure the angled top hole is large enough and has no ledge. The hole through the mast step is at the very edge to one side, if I recall correctly. Its a real hassle with how they had to do all of the wiring and several support pieces just to get the compression post a short distance out of the way.

Since you have the mast down, take a good look at your bulkheads that the stanchion plates bolt too. One of mine was completely rotted out. I also made brackets that bolted to the first port bulkhead to the shelf. The first port bulkhead is glassed to the hull and under the deck, but no support for the counter clockwise torque the stanchion puts on the bulkhead. as a results the deck starts to bulge up topside, and crakes the deck.

Here is some picures of what I'm talking about:







I drew in the bracket in black. I made one for each side and used through bolts. I also glassed in some support blocks. I did ad plates to each side of the spliced bulkhead. I will post this repair job when I get more time.

Good Luck and work safe

 

[BhamIslander]

Hey guys, I’m hauling my ‘76 Islander 28 next week and will be bringing the mast down and doing this repair. The stringer beneath the compression most appears to be rotting - it’s visibly deformed and sounds dull when tapped compared to the others. All of the photos you guys had posted are no longer available. Was wondering if anyone had time to reupload? Thanks so much for all this documentation. Saving my loads of time and stress.