Using Fastners instead of rivets

[Echo 78]

I have a 2005 13ft Scamp and I read awhile back that someone recommended using Stainless steel Fasteners because they last longer.
Can anyone steer me in the right direction?
Thanks

[Byron Kinnaman]

Originally Posted by Echo 78

I have a 2005 13ft Scamp and I read awhile back that someone recommended using Stainless steel Fasteners because they last longer.
Can anyone steer me in the right direction?
Thanks

There's been a lot of noise about using SS bolts and nuts vs Rivets. The factory used rivets and that's good enough for me. SS is generally not much stronger than aluminum rivets but a lot more expensive. I modified the propane tank hold down using SS bolts, why SS? Because with they get bent I can brake them off and replace.

[redbarron55]

I have never heard of anyone replacing a SS screw because it wallowed out it's mounting hole and was leaking.
I used all SS screws on my rebuild and have over 20,000 miles over the last three years and no leaks or loose screws.

[Tom Haberski]

Aluminum is not stronger in tension, compression or shear, all sizes being equal than S.S. The rivets are made of a pretty soft alloy....by design, so they can balloon out for fastening. This is an old topic, beaten to death on various fiberglass trailer forums and comes down to "use what you want".

[Byron Kinnaman]

Originally Posted by redbarron55

I have never heard of anyone replacing a SS screw because it wallowed out it's mounting hole and was leaking.
I used all SS screws on my rebuild and have over 20,000 miles over the last three years and no leaks or loose screws.

I've got over 100,000 miles with factory aluminum rivets and no problems.

[redbarron55]

Enjoy!

[SnowballCamper]

When washing my Bigfoot for the first time I noticed the rivets for the front window cover were rusty. When it comes time to replace them I definitely won’t use a rivet with two different types of metal (ok, maybe stainless and aluminum would be a ok).

[Wayne Collins]

Well, rivets ARE fasteners.
Mostly y'all are talking Pop Rivets, which allow you to install them without needing to get to the inside. They come in steel and aluminum.

Screws are best if you want to be able to remove or reuse them.
Our former Scamp Deluxe had the wood cabinetry inside so screws we're appropriate.
The plastic caps got old a brittle over time. I bought a complete set from Scamp, and replaced the washers and caps with a dab of silicone under each. Do one at a time, so nothing shifts inside.

[ARVZ]

This great paper on dissimilar metal corrosion has tables showing which fasteners are OK with which metal parts.



https://www.pdhonline.com/courses/s118/s118content.pdf


You can get stainless steel rivets, but have to be careful what other metals you use them with.


Stainless Steel Grades: This page has a great downloadable chart on the commonly used stainless steel grades and their uses. Note that not all stainless steel is suitable for marine use- if we camp or boat near the ocean much we need to pay attention to these details. The 316 series is best for marine uses, but most commonly available stainless steel hardware is not marine grade.

https://blog.mchoneind.com/blog/stai...l-grades-chart



Pressure Treated Wood: Another important aspect of dissimilar metal corrosion is that the most common pressure-treated wood chemicals are called Copper Quat (ACQ) and Copper Azole (CA) and they are extremely corrosive to galvanized steel hangers and fasteners. This is why we started seeing stainless steel joist hangers in the stores a few years back. The corrosion potential is so bad if you build a deck with ACQ pressure treated wood, you really should use marine grade stainless fasteners and design the deck structure so it does not depend on the continued existence of the joist hangers, nails, bolts, and other galvanized steel parts for structural integrity. Leaning against a railing nailed to a rim joist with galvanized steel fasteners is a dangerous act.


https://www.popularmechanics.com/hom...mber-15655848/


I started pulling coated decking screws out of my friend's 5 year-old pressure-treated wood deck with cedar deck boards and found they were already eaten half-through. This house is 10 miles from the Pacific coast. We bought marine stainless replacements and replaced every screw in the deck. It is expensive, but we can probably pull these screws and re-use them when the decking boards need to be replaced in a few years.

[Darral T.]

Rivets are fine until they get loose. There's no "tightening" them. I had mine loosen AND leak on my closet. They wallowed out, the rivets BENT... I replaced them with #10 SS screw/washer/nut. 3-4 yrs...no more problem. Obviously, this was in a stressful area on the body and that's why I replaced the alum. rivets. (2).

[Steve Hammel]

I actually used both. I needed to replace some rivets and didn't have a rivet gun or rivets. I did have several packs of stainless nuts and bolts as well as several plastic rivet covers. It worked excellent and never had a problem. I do like to lock the threads with something like locktite.

[Stephen_Albers]

If a rivet needs replacing it is because it is being over stressed. Rivets should merely hold parts together not have to withstand stress. Airplane wing rivets never need replacing from stress. The permanent solution is to eliminate the stress.

[Greg in BC]

Another option is to use nutzerts which are also called rivet nuts or anchor rivets. I have used them to replace screws that had loosened on a 1984 Bigfoot to hold the front canopy brackets in place. They come in aluminum or steel and are available at Princess Auto in Canada. This gives you a way of installing a nut on the inside of the fiberglass shell wall (from the outside) that is held in place, and then you can bolt through from the outside.

[Thomcat316]

Originally Posted by Echo 78

Can anyone steer me in the right direction?
Thanks

I'll try.

First, for stainless fasteners, call Parker Merrick in Florida at 800-432-3700 or 954-761-1677. Tell them that Whitney referred you, might get preferential pricing. Expect to buy boxes of 25-100 pcs.

Now for the complicated part.

Riveted and bolted (screwed) joints are intended to perform in exactly the same manner; the fastener pulls the joined parts together with enough tension that the joined parts cannot move, and sprung tension in the fastener keeps the joint from developing play and wearing loose.

Blind/POP rivets* typically use compression in the joined materials to provide this tension. In soft materials, if the area under the head or under the bulbed shaft is too small this tension won't last long, and loosening and leaks will follow. They are an ideal fastener for initial assembly, but don't have an infinite lifespan.

Bolted joints typically use the fastener as a sprung element, but that isn't practical in the case of thin fiberglass/wood structures, so the bolted assembly is once again the spring. When I through-bolt as we're discussing, I will typically use neoprene-bonded sealing washers on the outside, with either truss head or countersunk oval head** screws, metric fender washers to fit, and nylon-insert lock nuts. The neo-bonded washers are slightly conical, and between that and the rubber layer there's a pretty strong spring force. The metric fender washers are thicker than US standard, and don't sink into fiberglass or wood easily.

Bolted joints tend to hold up longer, seal better, can be retightened, and can be maintained. Riveted joints are quicker and a little less expensive, but don't last as long.

Complicated enough? :-)

*If you're going to use blind rivets, seek out "closed-end", which won't need to have the mandrel hole sealed to avoid leakage.

**Neo-bonded washers are a metal roofing or metal building fastener, if your local supplier has no idea what they are. If you want a larger washer and a very clean look, use oval head screws with a neo-bonded washer that the screw head sits down into. This won't be the "correct" size, but between head fill and gasket compression it works very well.

Next we can do bonded joints!!

[floyd]

Rivets work and work well. They have for nearly fifty years.
There were a couple of stress points on late model 13s which needed to be bolted. That is about 3 or 4 bolts in the whole structure.
Failed washers cause loose rivets, and washers fail because owners don't replace sun rotted snap caps in a timely manner.


Rivets have been the perennial subject of unfounded hyperbole.
I suspect this will continue ad nauseam.

[Steve L.]

Worse than that, I consider the constant resurrection of the topic to be an outright troll. Like the recent horsepower vs torque post a couple weeks ago. The guy admitted in his first post he knew there would be an argument... We apparently have no defense against it.

[redbarron55]

Originally Posted by Stephen_Albers

If a rivet needs replacing it is because it is being over stressed. Rivets should merely hold parts together not have to withstand stress. Airplane wing rivets never need replacing from stress. The permanent solution is to eliminate the stress.

As a licensed aircraft mechanic and authorized inspector I can tell you that the above is not true.

[Wayne Collins]

Originally Posted by Stephen_Albers

If a rivet needs replacing it is because it is being over stressed. Rivets should merely hold parts together not have to withstand stress. Airplane wing rivets never need replacing from stress. The permanent solution is to eliminate the stress.

Stress and Strain are engineering terms. Any machine that moves or has moving parts will experience both.

The purpose of fasteners, be they nails, rivets, bolts, screws. is to hold two parts of the machine together so they don't move relative to each other.
The choice of fastener depends on the materials involved, and the amount of stress/strain it will be exposed to.