Shimming my strut

[kito]

Well, I spent yesterday redoing my alignment job I did last weekend. As noted in a previous post, I found out the rear motor mounts ran out of down adjustment. Yesterday I raised the shaft log up and ground down a little of the mounting surface on the boat so the shaft log is angled a bit more. I found a great tip on taping hardwood dowels around the prop shaft at the area that will be inside to shaft log to help center it. I used my angle finder to take readings on the motor coupling, shaft log, shaft and strut. All is good except the strut (see pic). I am holding the strut at the approx. position it will need to be in. It is centered to the skeg and shaft and rotates freely (I temporarily bolted the strut up yesterday). Anyway, there is quite a gap. Just looking for suggestions on filling it. Use washers and use Sikaflex to fill in the gaps? Build up with West System and fair it?. This is a cast bronze strut so bending the tangs is not a good option.

 

[kloudie1]

It needs to be bedded in that position. Remember that it will have to be removed one day so when you bed it into the thickened epoxy on the hull, wrap the ears of the strut in something like saran wrap before placing it and blocking it into position while the epoxy sets..After the epoxy bed sets up, you can remove the plastic wrap and bed the strut normally. Careful to not epoxy the bolts in place. Good Luck

 

[kito]

Thanks Kloudie1. Great tip on using saran wrap. I was going to add thickened epoxy and fair it to fit. Using the strut as a mold will save some time and mess. Would I need to grind off the gelcoat in that area or will my West system adhere good if I just roughen up the gelcoat?

 

[kloudie1]

rough sand the gel and clean up and proceed.. The bedding job doesn't have to be pretty..so after you actually mount the strut, you can go back and fair the leading edge into the hull with an easy-to-work fairing compound (microballon or cabosil filled epoxy) instead of trying to fair the hard tough stuff you are bedding with. Good luck with it, Kito

 

[All U Get]

Kito,

Just a question about the strut, "Does it allow you to remove the shaft without having to remove the strut or rudder"? Mine is offset just slightly from center. If I have to remove my shaft I would remove the prop, undo the shaft coupler, and the slide out the shaft along the side of the rudder. Wish I had a picture to show the slight offset.

All U Get

Maybe your boat is different to allow for this.

 

[kito]

Kito,

Just a question about the strut, "Does it allow you to remove the shaft without having to remove the strut or rudder"? Mine is offset just slightly from center. If I have to remove my shaft I would remove the prop, undo the shaft coupler, and the slide out the shaft along the side of the rudder. Wish I had a picture to show the slight offset.

All U Get

Maybe your boat is different to allow for this.

Mine was setup with a slight offset to starboard but still had to grind a groove into the foam skeg to remove the shaft with the strut on. I am setting it up straight this time. I will have to remove the strut if removing the shaft next time.

 

[mitiempo]

I will have to remove the strut if removing the shaft next time.

Don't you mean remove the rudder?

 

[kito]

Don't you mean remove the rudder?

No. My rudder is mounted to a skeg. Removing the strut will allow the shaft to angle out a bit within the shaft log. I will only need to cut a groove into the foam skeg to remove the shaft. I would rather just patch and paint the foam skeg than remove it which would be a major project.

 

[dlochner]

It needs to be bedded in that position. Remember that it will have to be removed one day so when you bed it into the thickened epoxy on the hull, wrap the ears of the strut in something like saran wrap before placing it and blocking it into position while the epoxy sets..After the epoxy bed sets up, you can remove the plastic wrap and bed the strut normally. Careful to not epoxy the bolts in place. Good Luck

When you mount the strut prior to bedding it, use cheap bolts of the same size as the bronze one will use to permanently mount the strut. Prior to installing them, wax the bolts and nuts with good quality paste wax or mould release wax. Once the epoxy has cured the bolts can easily be removed and there will be threads cast in to the epoxy. Instead of using saran wrap, you can also wax the strut to keep the strut from sticking to the epoxy.

If you have areas where the epoxy will be very thick, you will need to keep the epoxy cool until it cures. Thick epoxy can generate a lot of heat and off gassing that makes the epoxy foamy and weak. Use a slow cure epoxy, mix it in a wide pan not a cup, and pick a cool day. The strut will act as a heat sink and that helps, but it may not be enough. Have some ice handy to cool the strut as the epoxy cures.

 

[rardiH36]

Anyway, there is quite a gap. Just looking for suggestions on filling it. Use washers and use Sikaflex to fill in the gaps? Build up with West System and fair it?.

kito:

I think I posted a link to a description of my strut replacement just a week or so ago ... which included the "filling the gap" material and steps that were recommended to me by the manager of the boat yard I hauled at. Post #10 in this thread:

http://forums.hunter.sailboatowners.com/showthread.php?p=1123679&highlight=cutlass