Outrage RPS Z-Leg Mounting Holes Stripped

Repair or modification of Boston Whaler boats, their engines, trailers, and gear
Striper15
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Joined: Tue Oct 20, 2015 7:42 am

Outrage RPS Z-Leg Mounting Holes Stripped

Postby Striper15 » Thu Aug 09, 2018 8:44 pm

Two of the screw holes where the Z-legs are mounted to the deck have stripped and now the screws won't tighten. Any recommendations on how to fix this problem? I was thinking about some kind of stainless steel rivet nut of other type of screw anchor. I don't want to use a well nut because I would have to enlarge the hole significantly.

Any recommendations? Thanks

jimh
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Re: Outrage RPS Z-Leg Mounting Holes Stripped

Postby jimh » Thu Aug 09, 2018 9:21 pm

For advice on repair of loose fastener holes, read

http://continuouswave.com/whaler/reference/FAQ/#Q7

and also read the articles from this search:

https://www.google.com/search?hl=en&sou ... gle+Search

Striper15
Posts: 26
Joined: Tue Oct 20, 2015 7:42 am

Re: Outrage RPS Z-Leg Mounting Holes Stripped

Postby Striper15 » Thu Aug 09, 2018 10:00 pm

Thanks, Jim. I like the method discussed in the FAQ best, although I was hoping not to drill a hole that large.

jimh
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Re: Outrage RPS Z-Leg Mounting Holes Stripped

Postby jimh » Thu Aug 09, 2018 11:23 pm

The attachment point for the seat legs should be into an area with wood reinforcement. Check that the wood is not rotten.

Striper15
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Joined: Tue Oct 20, 2015 7:42 am

Re: Outrage RPS Z-Leg Mounting Holes Stripped

Postby Striper15 » Fri Aug 10, 2018 7:45 am

Jim, I sure hope not. I do not feel any soft spots when walking on the deck. I researched the old forum and some recommended removing the inspection plates to try to detect if the backing wood is rotting, although this is not a true indication of potential rotted wood in the immediate area of the z-leg screw.

After removing the nearest inspection plate (approximately 1 foot from the area in question), I felt as far I could and found that the plywood is a little damp but seemed very solid.

Any other recommendations before trying the method of repair in the FAQ?

Thanks again!

jimh
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Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
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Re: Outrage RPS Z-Leg Mounting Holes Stripped

Postby jimh » Fri Aug 10, 2018 7:55 am

If the equipment to be mounted will completely cover the hole for the fastener, you won't have to make a cosmetically perfect repair.

I am not sure I would enlarge the old fastener hole to a much larger diameter and fill with resin. Instead, I would moderately enlarge the old fastener hole and install a wood plug, using epoxy adhesive to adhere the new plug and completely waterproof it. If the adjoining wood is solid, a new wood plug should bond to the old wood with the epoxy to produce a very strong attachment point.

If filling any large void with just epoxy resin, be aware of the problem of thermal runaway as the epoxy cures. Don't use pure resin; mix filler into the resin. Sawdust might be an applicable filler material, or the powered fillers provided by West Systems in their repair kits. A plug of pure resin will become very hot while curing, creating a "China Syndrome" effect of possibly melting other material around it.

If you do fill the hole with resin and fillers, use care when installing the new self-tapping screws. Cured epoxy is a hard material. Make a pilot hole for the new fastener that is appropriately sized so that the new fastener will not be trying to force itself into the material. Also, relieve the hole diameter at the surface where it is bonded to the gel coat layer; increase the diameter there so the new fastener does not crack the gel coat layer.

In the past when I have filled old fastener holes with a mixture of epoxy and resin, I carefully drill a just-undersize pilot hole, then slowly cut new threads with a self-tapping screw. I then unthread the screw that cut the threads, and install a fresh screw, orienting it so it uses the newly cut threads. I typically use that first screw over and over to cut the threads in any other holes that I repaired. This tapping screw will become quite warm from cutting the threads into the epoxy resin-filler mixture. Then I discard that tapping screw to the random spare screws collection. Also, I don't pre-thread the new holes all the way to the screw head being down right--I leave that last turn or two for the final screw to cut itself.

When installing new fasteners, I usually coat them with some sealant before I thread them into the pre-tapped holes. You can tell if your pilot hole was the right size by how much effort it takes to install the final fastener. Too little effort means the pilot hole was too big.