Since making the first travel mug using the Rocker Travel Mug Kit. I have gotten a lot of questions about them and how I make them. I made the first kit using the instructions that are supplied with the kit and this involved drilling out the blank used for the mug using a large bore bit. While making the first mug and with all of the questions I got to thinking of how I could make more of the mugs and how I possibly cast the insert into the blank and then turn away the excess. This presented a few unique problems. So I came up with the idea of using a technique that I have used before for a different application. Using a Pvc pipe as the mold for the epoxy.
This mug was going to be down with hard contrasting colors so with the use of black colored epoxy using the light colored hickory wood I know would have a great look. I stared off by cutting a piece of hickory into small slivers that would fit randomly into the mold around the steel insert of the mug.
Next I cut the 4 inch Pvc pipe down to length in this case 6.5 inches using the miter saw. The length of the mold would need to be a bit longer that the insert so that once the bottom of the mug is shaped it would not contact the bottom of the steel insert.
After the Pvc pipe is cut down to length it will need to be split cleanly down the center. Using a combination square I marked a line down the length of the pipe to ensure that I was able to cut straight down the center. I then used the band saw to split the pipe. To hold the pipe into place I used a wood clamp and a scrap block of wood to stabilize the clamp and ensure it doesn’t rotate as you are making the cut. This makes a nice clean cut down the length of the pipe also this can be a dangerous cut if made by hand as the pipe will have the tendency to roll. Splitting te pipe will allow for much easier removal of the epoxy once it is set.
If you do not take measures to prevent the epoxy from sticking to the mold it will stick to the insides and you will not be able to get the epoxy out of the pvc mold without possibly damaging the blank. To prevent this I use clear packing tape making sure to cover all of the inside of the mold . The epoxy will not stick to the no sticky side of the tape and will release cleanly. Try to get the epoxy as flat as flat as you can without any gaps or air pockets. Also make sure there are no gaps in the tape as the epoxy can find the gaps and will stick or can even get within the tape causing the epoxy to not want to release.
Once the inside of the mold is completely covered its time to assemble the mold. For this I used a hot glue gun. Start by applying a bead of hot glue down both edges of one of the pieces make sure it is a consistent line with no gaps. If you have any gaps in the glue go back and fill them in before continuing. After placing the hot glue press the two pieces together so that they line up equally. This needs to be done some what quickly as you do not want the blue to dry before the two halves are in place. If you glue sets and does not press out slightly with the haves pressed together take them back apart and start over. Making sure this seam is good and tight. Once the two halves are together and the seam is good and tight apply a seam of hot glue down the outside of the line where the two halves meet. Make sure like the inner bead that there are no gaps and that the seam is completely covered by the hot glue to prevent the epoxy from leaking out. Allow the glue to completely dry.
For this mold I am using 4 inch pvc pipe and while this works great and allows enough room for you to place wood or whatever you would like to cast around the mug into place the steel mug insert itself is only around 3 ¼ inches in diameter at its widest. The presents another problem with this process. The insert needs to be installed pretty much perfectly vertical in the mold and in the center of the blank. To get around this I used the i2R-8 Uccnc to machine a ring that would hold the steel insert perfectly centered and allow the mold to be completely sealed without the epoxy leaking into to insert or out of the mold. The insert would be pressed into place with the lower rim of the insert aligning perfectly with the inside of the ring. This will allow the epoxy to fill the void within the inner area under the top of the insert. While also make turning the ring and and excess epoxy off of the mug much easier. The ring is then sealed in place using hot glue. Just like the other seams make sure to completely cover the seam and have no gaps in the glue.
To ensure that the weight of the epoxy as well as the ring of the insert does not open the mold up allowing a leak I used clear packing tape wrapped tightly around the mold to secure it. While doing this I was pulling the two sides of the mold together as well as pulling the tape tightly around the mold. I also applied about 3 full layers to ensure the tape was plenty strong. You can now fill the mold once the glue is dry. In this case it was the strips I made earlier out of hickory.
As I said before the epoxy would be black I using some slow hardening Total Boat Epoxy. I also used a small hank held torch to help reduce the amount of air pockets withing the epoxy as I was pouring it. The heat will instantly pop any air bubbles embedded in the epoxy as it was being mixed. If you try this though be careful not to burn your hand, mold or the container that you are pouring the epoxy from. I also went back and added a bead of hot glue around the upper rim of the mold to ensure that the epoxy does not pour over the side of the mold. After filling the mold with epoxy I placed the mold into the pressure tank and allowed it to completely cure before removing.
To remove the mold it is pretty much the reverse of the process so far. Removing the tape and hot glue is pretty straight forward. Using a sharp chisel to remove the hot glue helps a lot. To actually open the mold first cut the hot glue in the seam along each side and then use a flat screwdriver or the chisel to open the seam. The mold half should release easily and completely without to much trouble as long as the tape was properly laid inside the mold.
To turn the mug I used the lathe flat jaw attachment. Make sure that the jaws are holding the mug tightly and use the live center on the tail stock to secure the mug in place as it spins. While making the initial cuts on the lathe take your time and do not rush them. I found it was easier to start at the top near the chuck and remove all of the spacer ring that I could and work down the mug before making the final passes to flatten the sides smooth.
The finish on the mug is done in a very similar was as to most other projects being finished with Starbond CA though this time it will be just a little different in that before applying the CA finish I first covered the rim of the mug with masking tape to prevent the finish from getting onto the rim. Once you have applied the finish remove the tape and sand the finish smooth. Wet-sanding will also help to prevent scratches in the finish as you go.
These are a fun project to make for gifts and I hope showing you this process has helped some in the making of these mug. If you are interested in any of the tools or materials I have used during this build the click the links in this article to take a look at them and go out and make your own. Make sure you Subscribe on Youtube and for more photos and videos follow me on Instagram @jpaywoodworking . If you want to show your support check out the shop tab at the top and grab you some gear. Thanks for reading guys and I will see you on the next one.