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We have all had to deal with Push Nuts in the past breaking off our beloved and rare scripts on our cars. Today in talking with CarFreak I was thinking there must be some better option. I designed these little clamps today. Next time I order some stuff from my 3D printing service I will get some made.

The top photo below shows a 1/8" dia., and 1/16" dia., stud for reference. I believe 1/16" is the smallest used anywhere, for example on the "Packard" dash script on the V8 cars. Most of the rest of the scripts use 3/32" or 1/8". To keep the design compact, the opening is sized for a 5/32" (nominal) pin, however it can be oversized with a drill to 3/16" and still work. (I don't remember if anything on these cars use 3/16".) As an additional feature, the sides of the part are shaped to an arc, so that they may fit flush with nearly all arced body panels, such as the dash, rear fenders, etc.

Feel free to let me know if you're interested, I can order more if there is some interest. Price only 50 cents each, but I think a minimum order of 20 per customer ($10) is reasonable, as far more than that can be used on one car.

Install tool is a 2mm hex key. I would highly recommend purchasing a ball end screwdriver for this purpose. Example:ebay.com/itm/264887619933

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Not a bad idea but one thing I would be worried about is the type and quality of materials used -- particularly the small setscrews. If a weak or inappropriate materials combination allows the set screws to rust or otherwise get seized in the threads, unlike a push nut where you can generally use some kind of sharp pointed tool to get under and spring or break the retaining tangs, a bound setscrew can be a real pain to free.

The equipment I worked on used multitudes of small metric setscrews, sometimes in very awkward places. I found it doesn't take much force with the smaller Allen wrenches or screws before they or the socket starts to round out. Ball end wrench tips can also be a weak spot and damage can happen in an instant if someone is aggressive when tightening or if you have a rusted one coming out. Either situation will give you a real problem and a chance to use your NSFW vocabulary. If the quality of set screw or wrench is low in the first place as many of the cheaper import ones are, the situation is even worse. I swear most of those import screws are designed for one time use and that one time isn't meant to be at removal.

I guess the point of this post is if the project goes ahead, please use absolutely top quality hardened setscrews. No idea what the body would be made from but hopefully something that won't react so as to rust or oxidize with each other after a short period of time exposed to humidity or polluted air.

An interesting idea. Howard, being that these things will be 3D printed, the body is likely to be some sort of plastic or hard rubber. So no issues with rust there.

PGH, my only concern would be how to access the set screw in some locations. But then again it's not like it would have to be turned much in order to release. So as long a hex wrench can reach it, it should be fine.

I really hate the speed clips that are on the emblems now. I broke off two tabs trying get all my emblems removed.

Yes, I forgot to mention (1 A.M.) that the body is plastic, and won't be tapped. The machine screw set screws will form their own threads when screwed in for the first time; this provides a natural thread-lock functionality. Set screw material is 304 Stainless. The plastic is a white stereolithographic resin (for easy visibility) with a >50 MPa failure strength, ~3 GPa elastic modulus, and over 5% elongation at break.

I had the same thought on accessibility but the push nuts are so ANNOYING that it's hard to imagine any scenario where these would actually be worse. I think the trunk and hood scripts will be a bit difficult, but the front and rear fender, and dash scripts, should be effortless.

Another idea I had would be to use a little piece of spring steel instead of a set screw, which could easily be released by a screwdriver. Basically the same idea as a Wago-type terminal block, except made as low-profile as possible, and the tension direction would be backwards. See the photo below. You shove a screwdriver in as the blue arrow, which pushes down the "guillotine" area of the metal (red arrow) and the wire is inserted where the orange arrow is. Once the screwdriver is removed, this is held in place. But to even do the simplest possible version as shown in my screenshot, would make them be like $3 apiece instead of 50¢, as I'd need to buy a large quantity and they would still be more expensive than the 3D printed "other half". With the current design, the 3D print is almost all the cost, and the set screw is very little, since tiny metric set screws are made by the tens of millions.

The bending tab could be made out of plastic but I have doubts about holding force, grabbiness (as the plastic edge would wear down upon first use, making the tab not actually grab into the post like a metal tab or push nut would), and fatigue life on top of that, so I don't consider it an acceptable solution.

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Something like how the dash knobs come off. You can get a better squash with a push. So the trim isn't loose.


Just would need a pick to unlock. And pull.

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Right, but the metal piece required makes them prohibitively expensive. If you can think of something off-the-shelf that would work to that end, I'm all ears.

Edit: Howard, regarding setscrew size, in my opinion a 2mm drive is about the smallest that reliably works well. But these shouldn't need a ton of torque anyway. Another option would be SHCS, to increase the drive size to 3mm, but cup point SHCS don't really exist.