There were no oil caps that spoke to me for the 280z (or they were $100+ billet caps). I have also been interested in the process of ordering 3D printed metal parts from China so decided to kill 2 birds with 1 stone and design my own oil cap and then send it off the China to be printed out of Aluminum. I opened up SolidWorks and got to work designing an oil cap vaguely based off the NISMO oil caps.

I ended up with 4 different designs.

After printing them all out of PLA to test the threads (I had to manually CAD the threads as the size and pitch were not an option in the thread tool), verify the o-ring groove had enough stretch, how they feel, and how they look on the valve cover, I decided to go with the bottom right design.

With the design chosen and geometry verified, I went to a website called CraftCloud and uploaded my model. CraftCloud is a website that aggregates companies that offer 3D printing services (both plastic and metal, CNC, Sheet metal fab, and casting services. You upload a model, chose the process you want, chose the material, and then you get a list of companies and their quotes for the model you uploaded. After a month of waiting, I had 4 oil caps (one cap ended up being below the minimum charge so I decided to order multiple) show up at my door. Final price (shipping + tariffs) was $237.87 for four caps (about $60 a cap). The initial quote was lower but the threads ended up needing to be post processed on a CNC grinder to remove support material from the thread teeth, this added an extra $90 to the price.

With the oil caps in hand, I decided to powder coat each one in a different color. Two of the caps I was a little overambitious and tried to do a 4 color powder coat but that ended up failing and I used enamel paint for the DATSUN logo and the sun. The multi-colored ones turned out a little sloppy but I'm happy with them since I've only ever done single color powder coat before.

I'm leaning towards using the multi-color bronze cap but haven't ruled out the bronze with polished logo.

Wow this looks like a fun project! The colored one is ok but I'd probably go for a silver/black or a black/black option. Some of us are sporting polished aluminum heads and don't really want the flashy colors.

Have you also checked to make sure the hood clears the cap? Sorry it's a dumb question but should be brought up. ;)

I also think it would be cool to fill the cap with clear epoxy like you see on some challenge coins.

5 hours ago, Mike said:

Wow this looks like a fun project! The colored one is ok but I'd probably go for a silver/black or a black/black option. Some of us are sporting polished aluminum heads and don't really want the flashy colors.

Have you also checked to make sure the hood clears the cap? Sorry it's a dumb question but should be brought up. ;)

I also think it would be cool to fill the cap with clear epoxy like you see on some challenge coins.

Clears the hood no problem!

I thought about fully polishing one but I didnt want to commit to all that sanding 😂

I love seeing inventive solutions. Your designs are outstanding.

Our oil cap thread is also shared by Honda.

Amazon brings up something like this. Has a nice flat surface waiting for just the right custom Datsun themed sticker or 3d printed emblem.