Mazda 323 BF rear subframe bushing

Mold files to recreate the Mazda 323 GTX rear subframe bushing which are NLA from Mazda. You will need the steel core from the original bushing, but I have included a file for the core if you don't have access to one.

The mold is 4 pieces and is held together with standard wood screws. I have been using a 2 part polyurethane that is about a 70 shore with good results. Once you have the mold parts printed out, coat EVERY surface with a bit of mold release wax. Automotive wax would likely work fine as well. Polyurethane will stick very well to PLA so make sure you do a comprehensive job coating the surface. Applying several coats is recommended. To assemble the mold, stick the smaller side of the steel core into the counterbore in the bottom mold. Assemble the sides such that the larger diameter is facing the bottom plate. Screw the sides and bottom pieces together, and finally the top piece. The mold is ready to use. The side pieces have 2 little holes near the bottom plate, you need to inject polyurethane into those holes at the same time. I use 2 10mL syringes like these. Inject the poly slowly into the mold trying to keep the material flowing evenly in both syringes. Fill the mold until the poly starts coming out of the top holes. Remove the syringes and plug the fill holes. If you have a vacuum pump I highly suggest pulling vacuum on the poly after you mix it to remove air bubbles. I also pull vacuum on the mold after I have filled it for about 5 min just to make sure there are no air voids in the mold, but you should get acceptable results just filling from the bottom up.

I've also attached a file for just the bushing area without the steel core as some people wanted to try and print the rubber area on it's own.

EDIT 5/18/2026 I've also added the mold to recondition the large fender washers as well.