What Kind of Backing Do I Need for My Bow Eye?

minuteman62-64

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I'm replacing the bow eye on my aluminum skiff. The old one was a badly corroded, plated alloy, single post type. Going with a "U" bolt type in SS.

The hull construction, where the eye is mounted, is an aluminum stem piece (first photo), capping the welded aluminum skin (second photo, from inside).

The old eye had a backing consisting of some sort of rubberized material (a tape??), that molded into the "V" of the inside of the stem, and a metal backing plate (third photo).

The new eye comes with inside and outside backing plates. However, the inside one will bear on the hull skin unless I add some additional backing similar to what was there.

What's usually used for backing in this situation? I need something that will mold into a "V" shape to match the inside of the stem.
 

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jbcurt00

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Re: What Kind of Backing Do I Need for My Bow Eye?

Do you already have the new SS 'U' bow eye?

What are it's diminsions?

If you bought a short 'leg' U bolt, it will require a thin backer, possibly of aluminum....

If you bought a long 'leg' U bolt, you can laminate & shape plywood (& sealed) to match the boat's contour....

You may need an outside backer plate too, looks like there is some damage around the thru holes:
attachment.php
 

minuteman62-64

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Re: What Kind of Backing Do I Need for My Bow Eye?

Already have the new eye - 3 1/2 inch long threaded sections so a shaped plywood piece would work.

The new eye did come with two backer plates, so I'll be using one on the outside and one on the inside.

What you are seeing on the outside shot of the stem is the single 3/8" hole for the old eye plus two smaller holes for little "studs" that were on the old eye to prevent rotation. My plan is to use the old 3/8" hole and drill one new 3/8" hole to fit the "U" bolt eye. I'll fill the two small holes with something (JB Weld?, 5200?, MarineTex?).
 

jbcurt00

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Re: What Kind of Backing Do I Need for My Bow Eye?

There looks like a slight crack running thru the 3rd hole up in the pix I posted.......

Any of those will fill the old holes.

Use the 5200 on the new bow eye's to seal the thru holes up when you install the eye........
 

minuteman62-64

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Re: What Kind of Backing Do I Need for My Bow Eye?

There looks like a slight crack running thru the 3rd hole up in the pix I posted.......

Took a closer look - not a crack - looks like a magic marker line, maybe drawn to center the holes when the original eye was installed.
 

minuteman62-64

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Re: What Kind of Backing Do I Need for My Bow Eye?

Another thought. I've got some epoxy putty that I purchased to stop some leaks in my pool skimmer box. From playing with left-over balls of it, from previous work, I've noticed it's pretty tough stuff once it sets up. I may try molding it into the "V" of the bow as backing for the eye. So, on the inside of the hull, moving from the apex of the "V" out, I'd have an epoxy putty backing, a piece of 1/8" 5051 plate (to spread the load) and the SS backing plate that came with the new eye. All fastened with the nuts that hold the eye in place.

Got to be better than the stuff that was originally in there (that's a question for you guys)?
 

GT1000000

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Re: What Kind of Backing Do I Need for My Bow Eye?

Piece of plywood shaped to fit and coated with epoxy is a very good idea...

Another thought is to try and find a piece of 3/4" or 1" thick Starboard material and shape it to conform to the inner V shape...with the SS backers it should hold up really well since it is a composite material and really strong, extremely rot resistant, although if left exposed to sunlight, the UV may break it down in time... plus it has a tiny amount of give to it, which should help to cushion the Bow eye...I have a piece of Starboard backing mine...

DSCF2742.jpg
 

gm280

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Re: What Kind of Backing Do I Need for My Bow Eye?

Not sure what the actual angle is on the inside of the boat. But if it is close to 90%, you could use a standard piece of angle aluminum to spread the load across a larger area and beef up the holding capability. I'm very sure a piece of angle aluminum of 2" X 2" x 1/4" thick and whatever length would suffice would work very nicely. And if that angle is not 90%, you could easily heat it up and change the angle a little to a better fit. That would illuminate the need for any wood that will eventually become crushed from the use and allow the eye to become loose over time. Just my stupid opinion... :D
 

jbcurt00

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Re: What Kind of Backing Do I Need for My Bow Eye?

You could use a standard piece of angle aluminum to spread the load across a larger area and beef up the holding capability. I'm very sure a piece of angle aluminum of 2" X 2" x 1/4" thick and whatever length would suffice would work very nicely.
Wouldn't this ^^^ just essentially make the hull thicker & still leave you a 'V' notch that you're trying to tighten washers & nuts down onto?

It still requires something solid to be shaped to match the V............ Now you'd be filling in the additional 2X2 1/4" aluminum angle's V....
 

minuteman62-64

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Re: What Kind of Backing Do I Need for My Bow Eye?

After pondering the advice, here's where I'm going.

First photo. I laminated 3 pieces of 5/8" ABX plywood, about 8" long by 2" wide. Used some 6-10 epoxy I had left in a tube from another project.

Second photo. Used my band saw to cut the lamination to the approximate "V" of the hull.

Next steps will be to use my spindle/belt sander to fine tune the "V" shape to match the hull (Not looking for a perfect fit - I plan to slather it with 3M 5200 at installation to fill any gaps), seal with epoxy and install.

Ran into a couple of problems. Kind of butchered the new hole through the bow (replacing a single stud eye with a "U", one hole was from the old eye) trying to drill into the apex of the "V". If I do it again, maybe start with a real small drill and carefully step up to the final hole diameter? Oh well. I'll do some hull patching while the epoxy sealer is drying.

Also thought I was being real clever on two points. First, made the lamination thicker than I needed, thinking I'd have to do a lot of shaping for a good fit - which would bring it down to a thickness good for the 3 1/2" "U" bolt. Didn't have to do much shaping at all for a good fit, so I have to sand away some more just to get the correct thickness.

Second, I carefully drilled the second hole in the stem and two holes in the lamination to fit the "U" bolt. However, when I went to dry fit the shaped lamination in the stem the holes wouldn't line up. Ended up using a bolt to secure the lamination through one hole and re-drilled through the other hole. Made the re-drilled hole slightly over-sized. Shouldn't be a problem since I'll be using a piece of 1/8" 5150 Al as additional backing

More to come (hopefully a success story :) ).
 

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Woodonglass

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Re: What Kind of Backing Do I Need for My Bow Eye?

When you coat it with epoxy, and Goop it all in with PC-11 (That's what I'd use) It will be there for your Grandkids to enjoy!!!
 

Yacht Dr.

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Re: What Kind of Backing Do I Need for My Bow Eye?

Not sure what the actual angle is on the inside of the boat. But if it is close to 90%, you could use a standard piece of angle aluminum to spread the load across a larger area and beef up the holding capability. I'm very sure a piece of angle aluminum of 2" X 2" x 1/4" thick and whatever length would suffice would work very nicely. And if that angle is not 90%, you could easily heat it up and change the angle a little to a better fit. That would illuminate the need for any wood that will eventually become crushed from the use and allow the eye to become loose over time. Just my stupid opinion... :D

Im with this dude with a stupid opinion .. gm280 has it right ..IMHO ..

Wood blocks ? erm .. angle alum for a backing. Are you trying to lift this boat out of the water alone from its bow eye.

Or do you plan on ripping apart your nose ?

A small backing plate with some washers should do it .. IMHO ..

YD.
 

minuteman62-64

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Re: What Kind of Backing Do I Need for My Bow Eye?

Are you trying to lift this boat out of the water alone from its bow eye.

Or do you plan on ripping apart your nose ?

A small backing plate with some washers should do it .. IMHO ..

YD.

Nope, just want to be able to pull it on and keep it on the trailer. In the photo, in the first post, you can see what the manufacturer provided - just a 5/8" x 2" piece of 1/8" aluminum, backed up with some sort of rubber stuff. That worked fine for 30 years, although it did distort the "V" of the bow slightly where the stud (from the old, single stud, eye) went in. Now that I'm replacing the eye, just looking to make it a little more substantial.
 

minuteman62-64

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Re: What Kind of Backing Do I Need for My Bow Eye?

After some delay from press of other projects, here's the new assembly (side-by-side with the old). Sealed w/West 105 and ready for installation. Might be overkill, but, gotta be better than what was there.

Paint probably not necessary, since it will be under the bow, but I had the paint and took the opportunity to continue to practice my "splatter" technique.
 

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GT1000000

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Re: What Kind of Backing Do I Need for My Bow Eye?

Looks Bomber strong...and the splatter technique is Koool!
 

Yacht Dr.

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Re: What Kind of Backing Do I Need for My Bow Eye?

You look good to go on this install :) ..

YD.
 

minuteman62-64

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Re: What Kind of Backing Do I Need for My Bow Eye?

And, here it is all bedded down in 5200 and tightened up. On the outside shot you can see the "overdrill" repair, w/MarineTex & glass, coated w/Rustoleum aluminum paint. On the inside you can see where things got kind of sloppy - but it's not highly visible.

Don't know if it will do any good or ever need to be tested, but, I coated the "U" bolt with Johnsons Paste Wax thinking it might make removal easier if I ever need to replace it. I've had good luck with Johnsons Paste Wax as an epoxy release - don't know about 5200, however.

Going to let it set for a week, then remove the nuts and add lockwashers (maybe also the additional backing plate of 1/8" 5052 aluminum, although I don't think it's necessary [but I have a big piece of it so might as well use it :)]).

Thanks to all whom provided comments/advice.
 

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73Chrysler105

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Re: What Kind of Backing Do I Need for My Bow Eye?

Looks Great,

Good job on that repair
 

Woodonglass

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Re: What Kind of Backing Do I Need for My Bow Eye?

That's about as good as it get's...
goodenuf.jpg
 

Yacht Dr.

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Re: What Kind of Backing Do I Need for My Bow Eye?

Looking good :) .. I dunno about waxing a through bolt thing though. I tend to wire wheel or scotch bright all my through bolt fasteners before the instal..

Might be just me kinda thing :) I have no problems getting fasteners out ..its those darn Plates that get me every time. But what can you do :D

YD.
 
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