www.iFourWinns.com

I don't know how you do it, but everytime I do it, I got problems.


What is the best type of stainless steel screw to use when screwin' speakers in fiberglass on a boat, light, medium, or course thread screws?

What happens, you crack the gel coat?

If so, you need to drill a bigger pilot hole. Unlike wood or metal, you can't use a small pilot hole and force the crew in, it just cracks everything.

The actual thread pitch will depend on the thickness of the area you're screwing .... kinda like choosing saw blades. Thinner material will use a finer thread pitch ...... thicker, use a more course thread pitch.

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Gordon Arnold
New Hampshire

2003 268 Vista ..................................................................Prior: 97 245 Sundowner

If at all possible, it's better to use nuts, bolts and washers; putting screws into a composite material is a horrible thing to do in terms of engineering practice!

Graham

This is the method I use and it's always worked for me.
Start the pilot hole and all successive holes drilling in reverse until just through the gel coat, then switch to forward. When you get to the final hole size, use a larger bit and just break the edge of the hole, again drilling in reverse.
This cuts back the gel coat from the edge of the hole so the screw can't catch the edge and chip it.
Works for me.

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"ROCKHOUND"
2005 Vista 298
Georgian Bay, Ontario.

You got my hopes up we were going to discuss something fun!!!

My wife lets me screw in the boat anytime I want as long as she's not around and it involves a drill

Some day we'll be alone, out on the high seas and i'll get her though

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Marc, Kathlin & Nathalie


'89 Chaparral Laser 32

'93 Vista 245, 5.8L w/ King Cobra

Former Boats
'01 H260, 7.4 VP Duoprop
'98 H200, 5.0 GL w/VP SX drive

Hmmm, I go away for awhile and this is what I get back to find you guys talking about. I can't turn my back on you kids for a second . . .

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2008 Four Winns 210 5.7 GI/SX
2007 GMC Sierra 2500 Crew
1966 Fed-Up Wife

Anytime you go straight for the screwing, there is gonna be some cracking.

Put a tab of electrical tape OVER the place you intend to screw. Drill a pilot hole of appropriate size through the tape. Remove the tape and screw away.

This typically helps cut down the cracking.

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Current Boat:
2004 Sea Ray 320 Sundancer "Nauti Luvin'"

Previous Boats:
1999 298 Vista "Seas The Day"
2008 H200SS "Nauti Luv"
2006 Tahoe Q4

I hate screwing in the boat I always end up with the hole bigger than I would like and then its a big mess.
Then I have to get out the gel kit and start patching.

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2006 F150 FX4
2008 H210 SS
5.7 GXI SX
Compass
Ratchet cover
Bow and cockpit covers
Bow cushions
Q&Q

........ Ummmmm .........

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Gordon Arnold
New Hampshire

2003 268 Vista ..................................................................Prior: 97 245 Sundowner

See what screwin on the boat got me?

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2001 Horizon 260 - 7.4 Volvo GSI DP

There are two reasons for pre-drilling. One is to, of course, avoid having the screw push enough material out of the way to cause movement and the resulting cracks. But the other reason is to help prevent spider cracks later on. You want to be very careful not to over-torque the fasteners (screws or bolts) into fiberglass. If you over-compress the fiberglass it will cause spider cracks to split outwards from the fastener. When you pre-drill the hole it helps to prep the hole almost as a countersink. If it's over-tightened this countersink sort of hole allows the material to push upwards toward the head of the fastener and not "as much" in an outward direction. But it's still important not to over-tighten.

I don't think I've seen many options for thread pitch when it comes to small screws in stainless steel. Most sized #8 and under look like a medium sort of thread.

-Bill Kearney

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-Bill Kearney, 2005 348 Vista

You got 20.00 for screwing on your boat?

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Current Boat:
2004 Sea Ray 320 Sundancer "Nauti Luvin'"

Previous Boats:
1999 298 Vista "Seas The Day"
2008 H200SS "Nauti Luv"
2006 Tahoe Q4

ROTFL

This is the effect Wifey and I are hoping for....the cash would just be a bonus though!

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Jon & Rhonda

'88 235 Sundowner
5.7L OMC Cobra
'01 F150 4.2L

There are plenty of pills out there to solve this.

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Walter

2003 248 Vista - VP 5.0 GXi
2009 Toyota Tundra SR5 5.7L 4x4