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I've a separate thread on my little outboard cruiser I've been building (Selway Fisher Clyde 18), and I'm now fitting hardware to it. Last night I was reading the Gougeon brothers document online about their suggestions of fitting hardware. A search on here showed builders liked some of their suggestions but not all. The main concerns I saw were that using epoxy could make future removal difficult or that the epoxy could crack, and the resulting seam would allow moisture in.
(1)At the basic level, drilling a pilot hole and coating the inside of the hole and screw thread before screwing up. Removal might not be too hard - solder iron on the head of the fixing to heat the screw and soften the epoxy would likely be ok. Probably for light duty.
(2) For fittings which would be held in with screws and not subject to too much stress, they suggest drilling a pilot hole, and then an over sized hole - pilot+6mmto 3/4's of the depth, coat the inside of the hole with unthickened epoxy, and then fill the hole with thickened epoxy - the last 1/4 can hold the screw until the epoxy cures. A countersink provides a bit more strength and then screw it all up. Again a solder iron would likely get the fixing out. They suggest bonding the fitting to the timber of the boat would add additional strength, but might cause more paint repair than necessary in the case of future replacement of the fitting.
(3)For fittings with through bolts (eg cleats) they suggest to drill and oversized hole as above and coat the threads with unthickened epoxy, fill the hole and the threads of the fitting with thickened epoxy and assemble it, until a small amount of squeeze out. In practice, I found it easier to drill the oversize hole, fill with thickened epoxy and wait until it cures before drilling it out for the bolt/machine screw. Thickened epoxy can be put on the thread/base of the fitting to take up any gaps before assembling the fitting on the boat.
There is ways of creating a threaded bush in the epoxy using release wax/oil, or drilling and tapping etc so the fitting can be threaded into the epoxy.
The don't (as you would expect) suggest using a sealant (Sika 291/3M4200 etc)/ butyl tape etc.
On my boat, I've got the sole hatches screwed to the sole and sealed with arbomast, my cabin vent is fitted the same way. Nav lights and all the other light duty bits and pieces I'll do this way
I've fitted two cleats on the quarter knees on my boat - I've fitted them using method (3) above. If they crack and water gets in, it's not a huge job to make new ones.
I've a few left to do - some grabrails for the cockpit - they're 900mm long and 200m high, with three fixing plates with 4 holes each. Because my boat has a self draining cockpit, the sole and side benches are raised, which means there isn't much height between the top of the seat and the gunwale, I wanted something on the gunwale. I'm thinking to use method (2) above. I can't really through bolt because of access and the shape of the inwale. I wasn't going to bond the underside of the feet to the top of the gunwale.
The bow roller - I have a central spine with timbers either side on my boat so can't through bolt. I have got 6x M8x60mm coachscrews which I'll fit using (2) above. I wasn't going to bond the underside of the roller to the deck. I'll probably keep the anchor in the foredeck locker when it's not in use.
Samson post - I'll through bolt this- probably using method (3).
When I looked through here and videos online (most were fitting to FG boats), there was nearly always a tube of sealant, rather than thickened epoxy around the threads.
How have you all attached fittings to your boat?
(1)At the basic level, drilling a pilot hole and coating the inside of the hole and screw thread before screwing up. Removal might not be too hard - solder iron on the head of the fixing to heat the screw and soften the epoxy would likely be ok. Probably for light duty.
(2) For fittings which would be held in with screws and not subject to too much stress, they suggest drilling a pilot hole, and then an over sized hole - pilot+6mmto 3/4's of the depth, coat the inside of the hole with unthickened epoxy, and then fill the hole with thickened epoxy - the last 1/4 can hold the screw until the epoxy cures. A countersink provides a bit more strength and then screw it all up. Again a solder iron would likely get the fixing out. They suggest bonding the fitting to the timber of the boat would add additional strength, but might cause more paint repair than necessary in the case of future replacement of the fitting.
(3)For fittings with through bolts (eg cleats) they suggest to drill and oversized hole as above and coat the threads with unthickened epoxy, fill the hole and the threads of the fitting with thickened epoxy and assemble it, until a small amount of squeeze out. In practice, I found it easier to drill the oversize hole, fill with thickened epoxy and wait until it cures before drilling it out for the bolt/machine screw. Thickened epoxy can be put on the thread/base of the fitting to take up any gaps before assembling the fitting on the boat.
There is ways of creating a threaded bush in the epoxy using release wax/oil, or drilling and tapping etc so the fitting can be threaded into the epoxy.
The don't (as you would expect) suggest using a sealant (Sika 291/3M4200 etc)/ butyl tape etc.
On my boat, I've got the sole hatches screwed to the sole and sealed with arbomast, my cabin vent is fitted the same way. Nav lights and all the other light duty bits and pieces I'll do this way
I've fitted two cleats on the quarter knees on my boat - I've fitted them using method (3) above. If they crack and water gets in, it's not a huge job to make new ones.
I've a few left to do - some grabrails for the cockpit - they're 900mm long and 200m high, with three fixing plates with 4 holes each. Because my boat has a self draining cockpit, the sole and side benches are raised, which means there isn't much height between the top of the seat and the gunwale, I wanted something on the gunwale. I'm thinking to use method (2) above. I can't really through bolt because of access and the shape of the inwale. I wasn't going to bond the underside of the feet to the top of the gunwale.
The bow roller - I have a central spine with timbers either side on my boat so can't through bolt. I have got 6x M8x60mm coachscrews which I'll fit using (2) above. I wasn't going to bond the underside of the roller to the deck. I'll probably keep the anchor in the foredeck locker when it's not in use.
Samson post - I'll through bolt this- probably using method (3).
When I looked through here and videos online (most were fitting to FG boats), there was nearly always a tube of sealant, rather than thickened epoxy around the threads.
How have you all attached fittings to your boat?
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