SS sheet metal screws vs aluminum rivets in spar??

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M. R. Bober

SS sheet metal screws vs aluminum rivets in spar??

Post by M. R. Bober »

RESPITE will be getting E-Z Jax this spring. Mounting hardware options include SS machine screws, SS sheet metal screws (self tapping) and either aluminum or SS rivets. I am uneasy about drilling & tapping while holding on for dear life (so the machine screw option is probably out), but I am curious about self tapping screws vs rivets. If rivets are chosen, I would opt for aluminum.
Any thoughts?
As always, best wishes.
Mitchell Bober
RESPITE
CD330
Don Carr

IMO Go with drill and tap

Post by Don Carr »

After installing bails for my vang, an additional cleat for reefing and speaking with a rigger- here is my opinion. Aluminum rivets are the most convenient way plus no disimilar metals. Now if you want something that will stand up over time...drill the hole and tap installing the hardware (SS american made) using Tef-Gel as a galvanic isolator. My logic is this: first the tapped installation allows for removal/inspection/replacement at some later date. Second rivets have a tendency (in this context) to not last in a shearing load environment and they wil fail when it is most inconvenient.
My opinion.

Fair Winds




carrds@us.ibm.com
len

Re: SS sheet metal screws vs aluminum rivets in spar??

Post by len »

mitchell

i agree with don - with a sharp drill bit and sharp tap, it's very easy to tap the mast or boom for SS machine bolts - with a bosun's chair you can be secure enough to do it aloft - don is also right about using something to avoid galvanic corrosion, Never Seize has worked for me - it is true i once dropped the drill which luckily missed my friend and impaled itself in the starboard cockpit seat, but it was easy enough to fix the hole - none of the fittings i have installed that way have failed - have fun

len



md.frel@nwh.org
len

Re: SS sheet metal screws vs aluminum rivets in spar??

Post by len »

mitchell

i agree with don - with a sharp drill bit and sharp tap, it's very easy to tap the mast or boom for SS machine bolts - with a bosun's chair you can be secure enough to do it aloft - don is also right about using something to avoid galvanic corrosion, Never Seize has worked for me - it is true i once dropped the drill which luckily missed my friend and impaled itself in the starboard cockpit seat, but it was easy enough to fix the hole - none of the fittings i have installed that way have failed - have fun

len



md.frel@nwh.org
John R.

Re: IMO Go with drill and tap

Post by John R. »

Ditto.........Machine screws is the way to go. Agreed the tapping while aloft can be a bit of a pain but the strength and ability to disassemble or replace fastener at future time is worth it. I use Bostick Marine Grade Neverseize on the fasteners.

Don Carr wrote: After installing bails for my vang, an additional cleat for reefing and speaking with a rigger- here is my opinion. Aluminum rivets are the most convenient way plus no disimilar metals. Now if you want something that will stand up over time...drill the hole and tap installing the hardware (SS american made) using Tef-Gel as a galvanic isolator. My logic is this: first the tapped installation allows for removal/inspection/replacement at some later date. Second rivets have a tendency (in this context) to not last in a shearing load environment and they wil fail when it is most inconvenient.
My opinion.

Fair Winds

sloopjohnl

Re: SS sheet metal screws vs aluminum rivets in spar??

Post by sloopjohnl »

lanyards on any item that can fall and impale a friend (your deckhand)or a loved one (your boat, i mean your wife) is a good idea.

len wrote: mitchell

i agree with don - with a sharp drill bit and sharp tap, it's very easy to tap the mast or boom for SS machine bolts - with a bosun's chair you can be secure enough to do it aloft - don is also right about using something to avoid galvanic corrosion, Never Seize has worked for me - it is true i once dropped the drill which luckily missed my friend and impaled itself in the starboard cockpit seat, but it was easy enough to fix the hole - none of the fittings i have installed that way have failed - have fun

len
Leo MacDonald

Go with drill, tap & SS machine screws

Post by Leo MacDonald »

Mitch,

I agree with Don. Tap the hole and install SS machine screws with some galvanic insulator goop. (Also no pointy end inside the mast/boom to drag internal lines across!!)

Fair Winds,
Leo



macdoNOSPAM@aol.com
John

Lazy jack attachment points

Post by John »

I, too, am planning on installing lazy jacks this spring (on my Typhoon), though of the home-made variety (two to four falls per side, I'm not certain yet, but patterned on the E-Z Jax system) and done while the mast is down. Is there any reason that I couldn't attach them to either the upper or lower shroud tangs or put a tang at the spreaders (I think the spreader brackets are through bolted). I'm just leery of drilling holes in the mast, especially if there's no set place that the attachment tangs have to be.

Thanks
John
M. R. Bober wrote: RESPITE will be getting E-Z Jax this spring. Mounting hardware options include SS machine screws, SS sheet metal screws (self tapping) and either aluminum or SS rivets. I am uneasy about drilling & tapping while holding on for dear life (so the machine screw option is probably out), but I am curious about self tapping screws vs rivets. If rivets are chosen, I would opt for aluminum.
Any thoughts?
As always, best wishes.
Mitchell Bober
RESPITE
CD330


john.hoft-march@appleton(nospam).org
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