Replacing Plastic Push Pin Clips With Rivnuts in Car

  • #1
YoshiMoshi
226
8
TL;DR Summary
Should I replace plastic push pin clips with rivnuts in my car?
I have a typical passenger sedan, and I see these little black plastic push pin fasteners holding my trunk liner to the trunk, splash apron underneath the car the subframe, the wheel well liners etc.. They are a pain to remove. I always have to pry on them really hard, and sometimes they brake or am worried that I'm going to ruin something in the process while trying to remove them. They are a pain to remove.

I get why these where used. You don't have access to the other side, so a typical bolt and nut will not work for fastening the two materials together. The sheet metal is to thin, so can't put threads in it. These plastic fasteners are very cheap. The two pieces cannot be fastened with a semi-permanent fastening mechanism.

But I was thinking of just replacing them rivnuts and bolts so I can avoid the frustration in the future? i don't see any bad side effects of doing this? I have steel rivnuts, did a magnet test on them, so don't have to be worried about galvanic corrosion, steel on steel. I know it will stick out like a sore thumb, but it will allow me to quickly unfasten the liners. It's a lot easier to work in the engine bay from below when you can remove the fender liners! But not when you have to fight with the silly plastic clips. But if I could just simply unbolt it, from the car, would do it every time for a wider viewing angle and greater access!

I've also learned of wellnuts, but I think they wont' last as long as rivnuts, and rivnuts are a better option?
 
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  • #2
Rivnuts would work, except that they may rust.
Consider using nylon screws, and having spares.
The head should have a big diameter and low profile, with PH2.
The available head may decide the screw thread selected.
 
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  • #3
YoshiMoshi said:
these little black plastic push pin fasteners
You'll get better advice if you tell us what kind of fastener you are talking about. Maybe a picture or a link to replacements?

YoshiMoshi said:
These plastic fasteners are very cheap.
So then you can buy an assortment from amazon and replace them if they are mangled after removal. Plus maybe a removal tool. All of this kit is cheaper than the rivnut equivalent.

YoshiMoshi said:
But not when you have to fight with the silly plastic clips.
Wait... I could swear I thought you said they were push pin fasteners.

YoshiMoshi said:
I was thinking of just replacing them rivnuts and bolts so I can avoid the frustration in the future?
Sure, go for it. But note that no real auto mechanic would do that. They would learn how to work with the original design, which may require some learning and tools. My experience has probably been similar to yours; very frustrated doing it the wrong way, then I watched some YouTube videos and bought some cheap tools.

As @Baluncore said, rust is an issue underneath cars, but maybe you live in Tucson where that never happens.

Do you mean these?
 
  • #4
I think the plastic pins/clips are used because they’re cheap and deter the less determined person.

As far as rivnuts go… I have used aviation rivnuts and they suck. They’re temperamental, easily damaged, and a pain to replace. I would not recommend them in the slightest. If you can get to the edge, I’d argue for clip style nutplates or Tinnermann nuts, tbh.
 
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  • #5
Baluncore said:
Rivnuts would work, except that they may rust.
Stainless rivnuts are available and cheap.
Flyboy said:
I have used aviation rivnuts and they suck.
That's interesting. What thickness of sheet were you using?
 
  • #6
sophiecentaur said:
That's interesting. What thickness of sheet were you using?
Generally .060 or less. Mostly for fairings on Cessna 172s
 
  • #8

1. What are Rivnuts and why use them to replace plastic push pin clips in cars?

Rivnuts, also known as rivet nuts or threaded inserts, are fasteners that create a permanent thread inside a drilled hole, allowing for the attachment of components with a bolt. They are used to replace plastic push pin clips because they offer a more durable and reusable solution. Unlike plastic clips, which can break or wear out, Rivnuts can withstand higher loads and vibrations, making them ideal for areas subject to frequent disassembly and reassembly.

2. How do you install Rivnuts?

To install Rivnuts, you first need to remove the existing plastic push pin clips and clean the area. Next, drill a hole at the appropriate size for the Rivnut. Insert the Rivnut into the hole, and then use a Rivnut tool to compress it, which expands the back side and locks it into place. This creates a sturdy, threaded receptacle for a bolt or screw. Ensure the Rivnut is installed flush with the surface to avoid any protrusions that might interfere with component fitting.

3. What tools are needed for installing Rivnuts?

The primary tool needed for installing Rivnuts is a Rivnut installation tool, which can be either manual or pneumatic. You will also need a drill to make the initial hole for the Rivnut, and possibly a drill bit of the correct size if one is not already available. Additionally, having a measuring tape or ruler and a marker or pen for precise placement is helpful.

4. Can Rivnuts be removed or replaced once installed?

Yes, Rivnuts can be removed and replaced if necessary. To remove a Rivnut, you can use a drill to drill out the center part of the Rivnut, being careful not to enlarge the original hole. This process should be done cautiously to avoid damage to the surrounding material. Once removed, a new Rivnut can be installed in the same hole.

5. Are there any disadvantages to using Rivnuts instead of plastic push pin clips?

While Rivnuts provide a more robust and durable fastening solution, they do have some disadvantages. Installation requires more tools and time compared to simply pushing in a plastic clip. Additionally, incorrectly installed Rivnuts can lead to issues like spinning or pulling out, which may require more extensive repairs. They are also generally more expensive than plastic push pin clips.

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