There seem to be nuts, or other threaded device, imbeded in the fiberglass deck where the 2 stanchion braces attach. We have some which do not hold tightly and appear "stripped". Has anyone experienced installing replacement "nuts" and if so, by what method? Can they be drilled out and some sort of "moly bolt" be substituted? Or is there a more satisfactory repair expereinced?
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Alum. backing plates.
Phyllis: Hunter many times will place an alum. plate under the fiberglass. This is then drilled & tapped and then a machine screw can be screwed in without any nut. If this is the case, what you may be able to do is retap the hole with a larger size tap and see if this does the job. You will also need to get matching screws/bolts before you start the job. PS: Always mention what model boat you have so you can get some more experienced advice.
Phyllis: Hunter many times will place an alum. plate under the fiberglass. This is then drilled & tapped and then a machine screw can be screwed in without any nut. If this is the case, what you may be able to do is retap the hole with a larger size tap and see if this does the job. You will also need to get matching screws/bolts before you start the job. PS: Always mention what model boat you have so you can get some more experienced advice.
As Steve has Mentioned ..................
............. this is exactly what we had to do to our "99 H310 in a couple of cases. If yours stanchion attachment is of similar construction, it should hold permanently (unless the bolt is overtightened again). Regards, s/v Island Hunter
............. this is exactly what we had to do to our "99 H310 in a couple of cases. If yours stanchion attachment is of similar construction, it should hold permanently (unless the bolt is overtightened again). Regards, s/v Island Hunter
what model/year?
My '88 33.5 has 3 bolts, 2 are thru-bolted with nuts on the end and one large one is drilled and tapped. The nuts are not all easy to get to.
My '88 33.5 has 3 bolts, 2 are thru-bolted with nuts on the end and one large one is drilled and tapped. The nuts are not all easy to get to.
Thread Inserts
You might like to enquire about stainless steel wire thread inserts. These are fitted after tapping out the existing alum plate a size larger. By this route you will have a stronger thread, can remove/replace the bolts many times without damage and still be able to use the same size of holding bolts. So no drilling out of the stanchion feet with the consequent weakening. Thread inserts are readily available through engineering materials sources and you might be able to borrow the kit or find a friendly engineer to come and do the job. An hour should be plenty of time.
You might like to enquire about stainless steel wire thread inserts. These are fitted after tapping out the existing alum plate a size larger. By this route you will have a stronger thread, can remove/replace the bolts many times without damage and still be able to use the same size of holding bolts. So no drilling out of the stanchion feet with the consequent weakening. Thread inserts are readily available through engineering materials sources and you might be able to borrow the kit or find a friendly engineer to come and do the job. An hour should be plenty of time.
Another Opinion
I had a similar situation occur and just drilled and tapped for the next size bolt. By carefully measuring the depth of the current hole, you can put a piece of tape on a drill bit to make sure you don't drill all the way thru the deck. Then use a normal tap to start the hole in the aluminum plate, and a bottom tap to complete it. That way you make sure you tap completely thru the plate. The stock holes in my stanchion bases were just large enoughf or the next size bolt without modification. While installing an insert would make for stronger threads, you would have to drill thru the deck with an oversize bit to accommodate the insert. This would give little side support for the stanchion bolts, allowing the stanchion to move when loads were applied. This would break the grip of any bedding compound used, allowing water to migrate into the deck, an unwanted situation. Just another opinion.
I had a similar situation occur and just drilled and tapped for the next size bolt. By carefully measuring the depth of the current hole, you can put a piece of tape on a drill bit to make sure you don't drill all the way thru the deck. Then use a normal tap to start the hole in the aluminum plate, and a bottom tap to complete it. That way you make sure you tap completely thru the plate. The stock holes in my stanchion bases were just large enoughf or the next size bolt without modification. While installing an insert would make for stronger threads, you would have to drill thru the deck with an oversize bit to accommodate the insert. This would give little side support for the stanchion bolts, allowing the stanchion to move when loads were applied. This would break the grip of any bedding compound used, allowing water to migrate into the deck, an unwanted situation. Just another opinion.
Not Quite So
Mike W may not have seen a Helicoil Thread Repair Insert kit. It comprises a pre formed wire spring which IS the next size up thread in outer diameter and the original size thread inner diameter. Accordingly it will not reduce the strength of either stanchion base or glassed in plate. Often they are used as original equipment in aerospace applications. Other trade names are ReCoil. Hope this clears up any misunderstandings.
Mike W may not have seen a Helicoil Thread Repair Insert kit. It comprises a pre formed wire spring which IS the next size up thread in outer diameter and the original size thread inner diameter. Accordingly it will not reduce the strength of either stanchion base or glassed in plate. Often they are used as original equipment in aerospace applications. Other trade names are ReCoil. Hope this clears up any misunderstandings.
thread inserts
Don's on the right path-helicoils are widely used in the aerospace and automotive world to strengthen aluminum threads-but-you have to use the special helicoil tap, not just the next larger size regular tap-you can get the right kit at most decent automotive stores, or at a speed shop
Don's on the right path-helicoils are widely used in the aerospace and automotive world to strengthen aluminum threads-but-you have to use the special helicoil tap, not just the next larger size regular tap-you can get the right kit at most decent automotive stores, or at a speed shop
Stainless Steel and Aluminum
Since stainless steel and aluminum have a tendency to have problems when adjacent to eachother, would one want to use an antiseze compound? Or would the bonding in this situation actually be advantages?
Since stainless steel and aluminum have a tendency to have problems when adjacent to eachother, would one want to use an antiseze compound? Or would the bonding in this situation actually be advantages?
helicoils
the helicoil insert looks like a spring, but the outside edges of the coil are designed to dig into the aluminum. the coil has the bottom end bent into the center-this tang is grabbed by the install tool, and can be broken off th make the installation permanent-and a clean hole for a thru bolt, or left in, used with a short bolt, and removable by screwing it further in with the install tool. the tool compresses the coil as you screw it in, and then it springs out and grabs the walls when you remove the tool. sorry for the long winded tale, but by all means use anti seize if you want to-if you don't, the coil will grow into the alum and be permanent!
the helicoil insert looks like a spring, but the outside edges of the coil are designed to dig into the aluminum. the coil has the bottom end bent into the center-this tang is grabbed by the install tool, and can be broken off th make the installation permanent-and a clean hole for a thru bolt, or left in, used with a short bolt, and removable by screwing it further in with the install tool. the tool compresses the coil as you screw it in, and then it springs out and grabs the walls when you remove the tool. sorry for the long winded tale, but by all means use anti seize if you want to-if you don't, the coil will grow into the alum and be permanent!
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