Decoring/through bolt short cut?

backman

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I'm skeptical - need a reality check here.

My marina suggests that I can drill holes for throighbolts, decore, fill the holes with epoxy and put the bolt in while the epoxy is hardening to avoid a 2nd round of drilling later on.

Good practice or bad practice?
 

Capt Dave

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I'd say bad practice. One of the reason for the decored/epoxied area is so the bolts won't compress the cored material and have something solid to seat against. If the epoxy has not hardened you could still compress the core.
 

jerseysportfisher

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No, unless you wax the bolt you'll never get it out. Drill hole bigger then bolt, fill hole (doen't need to be epoxy) it can be poly mixed with cabosil / micro balloons. Re-drill for TAP size, then tap hole.
 

hntrss

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I have installed many items, on many boats. A great trick that works well for me is to get a piece of aluminum tubing with an inner diameter the same as the bolt going through whatever it is you are mounting. Drill the hole for the OUTER diameter of the tube. Hold the tubing so it is exactly flush to one side of the hole. Have someone mark it where it comes through the other side. Now cut the tubing and done correctly, you have a piece that is exactly flush on both sides of material. Next I epoxy the outer of the tubing and install it in the hole, taping it in place. After it sets up, you can mount whatever it is, with some sealant and you have a waterproof, crush proof fastening. I have always felt that crushing causes more water intrusion than anything else. Try it, it works well. Home Depot, lowes and ace hardware all have many different size tubing and its reall easy to cut.
 

pugsley

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it's really not that hard to drill a hole, even if you have to do it twice
 

hntrss

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I use the tubing more on hardtop type installs, which on boats like center consoles and such, they typically have real thin skins and real prone to crushing.
 

backman

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Thanks - we have drilled twice the diameter; decored and filled w/ West 610 and will redrill w/ the proper diameter tomorrow.

Apperciate the help - as I started this thread - I was skeptical of my marina's "advice".
 

Sailorgp

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bad practice...plus I suspect it'd be messy as hell fooling around with 'still gooey' epoxy
 

starrfish

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i swiped this idea from someone else so i cant take credit for it.... but he used a hole saw, say 1 1/4, for a 5/16 bolt..BUT only drilled through the glass and core from one side, thus leaving a 1 1/4 hole on one side, and just the pilot bit through the other.. filled with thickened epoxy, then redrilled for the bolt.. was a great idea that works mint, and the epoxy isnt running outa the giant hole, you dont need a waxed block backer on the opposite side etc..
 

DBM

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Capt. Rick

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Anyone know where to get a de-coring bit? Yeah you can you an allen wrench or similar. My builder had a very nice bit with carbide teeth which made short work of de-coring holes.....have never seen one since?
 

F/V First Team

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slot-cutter-router-R-5206-RB3W.jpg


You can make your own with some fender washers, a bolt and a lock nut. Just cut some teeth in the edge of your washers and cut a relief on the trailing edge. Easy peasy.

You guys and your epoxy.
 

Red Sprague

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Any reason you can't just goop up a machine screw or bolt with 5200 and use a backing plate or fender washer on the nut side? Are builders decoring every through bolt/screw mount?
 

Blitzen

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slot-cutter-router-R-5206-RB3W.jpg


You can make your own with some fender washers, a bolt and a lock nut. Just cut some teeth in the edge of your washers and cut a relief on the trailing edge. Easy peasy.

You guys and your epoxy.

If you want to just buy one it is called a slot cutter. Any decent router bit supply will have them for about 12 bucks.
 

F/V First Team

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Any reason you can't just goop up a machine screw or bolt with 5200 and use a backing plate or fender washer on the nut side? Are builders decoring every through bolt/screw mount?

Every. Single. One.

Good builders at least, not sure what those other guys do...
 

captchuck

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i swiped this idea from someone else so i cant take credit for it.... but he used a hole saw, say 1 1/4, for a 5/16 bolt..BUT only drilled through the glass and core from one side, thus leaving a 1 1/4 hole on one side, and just the pilot bit through the other.. filled with thickened epoxy, then redrilled for the bolt.. was a great idea that works mint, and the epoxy isnt running outa the giant hole, you dont need a waxed block backer on the opposite side etc..

I do lie this approach my self but I only go about an 1/8 to a 1/4 bigger than the hardware
 
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