Epoxy Resin Screwdriver/Nut Driver From Silicone Mold Making to Casting Resin Parts
Introduction: Epoxy Resin Screwdriver/Nut Driver From Silicone Mold Making to Casting Resin Parts
I've been wanting to make this screwdriver/nut driver/bit holder for quite some time but just never got around to it. The reason I wanted to make this was so that I could easily change the nozzle on my 3d printer. My Ender 3 came with a small 5mm wrench to remove the nozzle but since you have to change the nozzle when its hot it can be a little intimidating to do so with a tiny wrench. Also the wrench loosens the nozzle but doesn't hold it so you either have to put on a glove and catch the hot nozzle or just let it drop. I have a screwdriver/nut driver but it has a long handle and I have to raise the printer head all the way up in order to have enough room for the screwdriver to fit. So I knew I wanted a stubby screwdriver something that was small enough to store in my 3d printer tool box too. I decided to use a Craftsman screw driver as my model because I like the size and shape and how it feels in the hand.
Originally I was just going to make one or two but I have to admit the molding and casting process was so much fun that I made several different colors. It is really satisfying pulling out an almost finished piece from a mold especially when they are different fun colors.
Step 1:
I knew I was going to use a PVC pipe for the mold but I need a way to hold/suspend the screwdriver in the mold while the silicone cured. So I used a scrap piece of wood with a hole drilled in the middle to hold the shaft of the screwdriver.
Step 2:
I used a piece of 2 inch PVC that was cut to just larger than the screwdriver and used my center finding jig to find the center. I made a few marks on the top rim so that I could align the screwdriver in the center of the jig. This doesn't have to be exactly in the center, close enough is good enough as long as the model is entirely encased in silicone. I also used some duct tape to seal off the bottom of the mold.
Step 3:
I made sure to spray the inside of the mold with mold release. The inside of the PVC wasn't that smooth so I thought this would help me later with releasing the mold once it was cured. The silicone comes in a two parts and has to be mixed in the correct ratio by weight per the instructions.
Step 4:
Once the silicone was mixed I placed the screwdriver in to the mold and moved it to one side so I would have enough space to pour in the silicone. Once it was nearly full I moved the screwdriver to the center using my marks on the rim of the PVC as reference. 582
I placed the mold in my pressure pot, sealed it and pressured it up to 50 psi. I let it cure overnight.
Ideally you would want to use a vacuum chamber to degas (remove all the air bubbles from the silicone mixture) before pouring it in to the mold. However I do not have a vacuum chamber so instead I used my pressure pot which doesn't work as well but works well enough for my purposes. I've had good results in the past using my pressure pot to cure silicone molds.
Step 5:
Once the silicone cured overnight I removed the mold from the pressure pot. I removed the wood and tape and tried to use my air compressor to free the silicone mold from the PVC. This didn't work, so instead I used my portable bandsaw table to cut a slice in the PVC lengthwise to free up the silicone. If you don't have a portaband you can use a hacksaw instead. This worked out very nicely.
Step 6:
Now it was time to remove the screwdriver. First I made two slits on either side of the screwdriver shaft, next I cut down the side of the mold in a zigzag pattern about 2/3 of the way down the mold. The zigzag acts as a registration mark for later. I made this cut slowly and deliberately making sure not to cut too far down. I only cut enough in to the mold so that I could remove the screwdriver model.
Step 7:
I used Total Boat's Medium Hardener epoxy for this project. Any epoxy will work its just that this epoxy had been in my garage for quite some time and I figure I could use it up for this project instead of letting it go bad. I mixed the epoxy per the instructions and add some blue alcohol ink to the epoxy and mixed it all together. I used the PVC pipe to hold the mold together, this worked out quite nicely. 254