Boat rivet repair question from a friend

Find an airport and pay a visit to the local repair parts facility and buy some aircraft grade rivets. Drill out the old rivets and use new rivets, of aviation quality and you'll never be bothered with loose rivets again. The rivets commonly used n alum boats are very solf "O" but a good AD grade is slightly harder but still easy to set/buck. ONly way to tell if you need oversize is by gauging the hole after rivet is removed, as it can wollow from being loose and flexing.

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And put some silicone on the rivet before popping it. My neighbor repaired a million pinholes on his boat using the soft rivets and silicone, but they weren't structural and so likely to work loose. You can also do a quick search for "Aircraft Spruce" and "Wicks Aircraft Supply" and they have the rivets you need.

| >===Loose rivets. | >=== | >===I am working on 1973 Starcraft aluminum boat. Some rivets are slightly | >===loose. Should I just hammer them , or drill out and put new ones. I | >===would think they could loose strength after being streched. Thanks for | >===advice. They appear to have 1/8 diameter shank. | | | ============================================== | Put some color in your cheeks...garden naked! | | ~~~~ } ~~~~~~ } ~~~~~~~ }

Thank you Roy and Carl.

i

Do NOT do this! -- or not unless you can be very sure of the exact content of the alloy used in the rivets. Alloys used in aircraft construction tend to have a high copper content, and a mix of copper and aluminum is the very last thing you want in salt water.

A lot of aircraft aluminum was used in boat construction when aluminum boats first came into wide production, and this has led to a lasting prejudice against alloy hulls. They just corroded all to pieces, way too fast. There's a good chance that this is the problem with the original rivets in the 1973 hull to begin with. It wasn't until later on that builders (and insurers) came to understand just how quickly the wrong aluminum can disintegrate in salt water.

Don't discount aircraft stuff out of hand; but be sure that it's not full of copper before you use it. If the supplier can't verify that, run away.

Pete

he is using his boat in fresh water exclusively.

Anyway, I found a good quantity of aluminum screws (aircraft and general duty) in my military surplus shitpile. It's all the stuff that I removed from military equipment that I could not sell. Screws, other fasteners, some control pieces etc. Turned out that I had a bunch of nice 10-32 aluminum screws, including some amusing ones with the hole for allen wrenches on the SHARP end, and flat (no slot) conical head.

So, that's probably the answer to his needs, I will give them to him, about 100-120 in total.

Thanks for interesting information!

i

140 hp on a 18 ft aluminum boat???

/Ignoramus20962 faints

*THUD*

that must be a hell of a speedboat! My boat is 21 years old (very thick fiberglass) 21 foot and has a 228 HP mercruiser, much much heavier than yours, so it is slower. Top speed only 35 mph, which I rarely do.

i

Yes, now I think that they are titanium pins. So, this means that I will be giving to my friend both titanium pins, as well as aluminum screws.

Very interesting!

Well, looks like it is inappropriate to use titanium with aluminum, so I doubt that he will use them on the boat...

i

| >>>SNIP . Turned out that I had a bunch of | >| nice 10-32 aluminum screws, including some amusing ones with the hole | >| for allen wrenches on the SHARP end, and flat (no slot) conical head. | >>>SNIP | > Look like this?

| | Yes, now I think that they are titanium pins. So, this means that I | will be giving to my friend both titanium pins, as well as aluminum | screws. |

| > the shear type nuts off, it pretty much looks like a split nut cutter or | > evil looking pair of pliers. Really easy to screw up getting them out, and | > usually you'll have to go oversized when you replace them anyway. | | Well, looks like it is inappropriate to use titanium with aluminum, so | I doubt that he will use them on the boat... | | i

Well, most likely the pins are coated with a stuff that allows them to be used in aluminum. Only when stainless or funky allows are used are the pins installed "wet" with sealant to prevent corrosion. Keep in mind that if there is no gap of any kind to allow moisture or air into the joint, corrosion will be unlikely to start.

you are right, they are coated with golden colored coating.

i

What??? This is a boat, right? You can COUNT on moisture getting to the rivet and the fayed surfaces.....

Your best bet will be the aviation rivets as recommended, but I can't tell what kind of material your boat is made from.... since the manufacturer has no technical information available on the website

Now, as for the rivets, it is likely that your best choice will be a "B" type rivet or one made of 5056 aluminum.... although if you can find what the manufacturer originally used in the sheet metal, I can give better advice.

I would advise against using the hi-locks mentioned in the above thread, since they require special tooling, and will project quite a bit into the inside of the boat.

In any event, whether you choose hi-locks or rivets they should be installed wet, either with a coating of zinc chromate or an epoxy sealer....

If you can determine a bit more about what you need, I can help give you the mil-spec, AN, or NAS nomenclature needed for ordering....

| > Well, most likely the pins are coated with a stuff that allows them to | >be used in aluminum. Only when stainless or funky allows are used are the | >pins installed "wet" with sealant to prevent corrosion. Keep in mind that | >if there is no gap of any kind to allow moisture or air into the joint, | >corrosion will be unlikely to start. | | What??? This is a boat, right? You can COUNT on moisture getting to | the rivet and the fayed surfaces..... | | Your best bet will be the aviation rivets as recommended, but I can't | tell what kind of material your boat is made from.... since the | manufacturer has no technical information available on the website

I think the OP had no expectation of using these on a boat, but the interest was that they were an unusual fastener he'd never seen before and it wasn't immediately obvious how the thing was supposed to work. Compared to stuff on the outside, they are really cool fasteners, though.

Before you get ready to install the rivets, you need to make sure you have clean and round holes of the diameter required by the fastener's manufacturer. The structure/layers need to be smooth and burr/bump free. The fastener should fit cleanly into the hole and the head should be flush with the surface. I recommend dipping the fastener in sealant after you've put it in the puller, but the important thing is that any and all cavities that collect or seal in moisture or water should be filled. After pulling the rivet, wipe the excess sealant off. After you've installed a number of fasteners, work a little sealant all around on the inside of the fastener with a good tool. I prefer an artist's mixing knife, but something flexible that creates a void free sealing surface will do. If you've got some bad holes, and I'm sure you will, then you can use snug fitting aluminum washers to seal up and reinforce the damaged area. The hardware store ought to have some thin washers. SAE washers are too big, it seems like last time I used that method, I used metric washers or something. All surfaces full of sealant, still. Ask a boat shop for recommendations on good sealants. They will have the best stuff to use, and _don't_ select it based on cost.

O'course there's another way, which, depending on how many rivets are bad, might be more sensible. You could drill 'em out and MIG the holes full. The gob of weld material left over, you can take down with a router or a block plane.

It's bodgery, but it does work. Just a thought.

I'd have to dissagree on shooting rivets in an aluminum boat "wet' Been around and worked on a lot of them already as well as aircraft for over 30 years and there is very few areas where there is a need to shoot a wet rivet or fastener, with the fuel cells or pressurized cabins being the most common areas. A properly installed rivet shuld not leak period. An aircraft is not in a wet environment per se, but flying at high speeds in rain will certainly push and make water get into areas its not supposed to be in and still they are not shot wet.

Most rivets used on aluminum boats are upset or bucked, not pulled!

============================================== Put some color in your cheeks...garden naked!

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snip

Round holes of the proper diameter that are burr free and using the proper length rivet is probably the most important part.

============================================== Put some color in your cheeks...garden naked!

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"~Roy~" wrote in message news: snipped-for-privacy@news.east.earthlink.net... | | I'd have to dissagree on shooting rivets in an aluminum boat "wet' | Been around and worked on a lot of them already as well as aircraft | for over 30 years and there is very few areas where there is a need to | shoot a wet rivet or fastener, with the fuel cells or pressurized | cabins being the most common areas. A properly installed rivet shuld | not leak period. An aircraft is not in a wet environment per se, but | flying at high speeds in rain will certainly push and make water get | into areas its not supposed to be in and still they are not shot wet. | | | Most rivets used on aluminum boats are upset or bucked, not pulled! | | ============================================== | Put some color in your cheeks...garden naked! | | ~~~~ } ~~~~~~ } ~~~~~~~ }

We are both correct, but for different reasons. You are very correct when you say that a properly installed river should not leak, but unfortunately, on a boat, and with the membership of this group not being boat or aircraft people (no insult meant) there will undoubtedly be a few (or more) holes or rivets that are far from perfect, so the sealant is there to make up for what is less than perfect. If it were a boat that were mine, I'd for sure teach someone in my family how to buck and we'd go to town, but that's an investment of time, tools, and skills that most folks don't have. En masse on an assembly line it makes a lot more sense. Good pop rivets and sealant _should_ make up for most deficiencies inherent in the general population. I'd just as soon add the extra layer of security, especially considering the cost of doing it vs. not doing it and having a dozen or more slow leaks that require rivet removal, which makes bad holes worse.

Huh? The original poster stated his purpose in posting with, "I am working on 1973 Starcraft aluminum boat."

I don't recommend, and the original responder mentioning AD rivets did not allude to, "pop" rivets, but to solid rivets.... which are MUCH better at accomplishing this job that something like a CherryMax rivet, which is quite expensive and requires a special puller to seat the ring. IMHO, pop rivets are a very poor choice in boat construction or repair. They are useful only if you can't get to the back side of the repair to form a shop tail.

That should be totally unnecessary and must look like crap.

That concept subverts the whole concept of how a hole filling fastener, such as a rivet, should work. Oversize holes *require* reaming to the next oversize and installing the appropriate fastener.

Many SRMs on transport category aircraft require this... although this is not specified in the maintenance publications for smaller aircraft. I think it makes good sense to install rivets wet when one knows that the function of the rivet will be to seal against fluid... and in my thoughts, salt water. In my mind, there is little functional difference between a fuel cell and a boat. And anybody that has 30 years of experience working with wet wings must know that they are prone to leakage.... just as a boat is...

Agreed.