Once again I have been making progress with the plexiglass clock project. If you have been following along with the blog you already know that I have been experiencing problems trying to engrave acrylic plastic for this project. Yesterday I finally received the cast acrylic plastic that I needed for this project and this is the progress that I made with this new material.
I first mounted the 1/4 cast acrylic plastic on to the CNC machine with clamps and double stick tape then engraved the clear blanks that will be used in the clock to show the time.
Next in the process I changed the engraving bit in the CNC to a 1/4 inch plastic cutting bit. This did some nice work on cutting the plastic. I was happy I took great care in working out the drawings and the conversions of the images to Gcode so that the cutting bit matched up perfectly with with outer perimeter that was engraved in the plastic for the blanks. Each black measures 3 x 1 inches in size.
This looks like I just covered the entire machine with either snow or shaved coconut. The shavings looked interesting but even with my vacuum running I could not keep up with the debris that was flying off of the cutting bit. Not really as bad as it looks here. It only took me a couple of minutes to vacuum up this mess after I had completed the cutting of the parts. Interesting looking just the same.
All the blanks are cut out now.... all 27 of them. I was happy to get this part of the project done as it is a critical set of parts that needed to be just right as all of this work will show once the clock in up and running.
These two photo show what the blanks will look like once they are installed into the two vertical supports. Needless to say I will have to be very careful about installing these parts. The dust on the blanks really shows up easily. I think I will have to be in a sterile clean room with surgical mask and gown on to put the clock together. (Just kidding). Actually I think if I eyeball the blanks and clean them as I install them I should be fine.
Here is a good exploded view of the inner workings of the plexiglass clock. The clear blanks are installed into the two vertical support pieces. Then a black painted back board is slid into place between the two vertical supports and a clear face plate is slid into the front of the case. This is then finished off with a top and bottom mounting block. I still have to figure out how to hold this all together. But my first thought is that I will bond it together using epoxy resin and fiberlgass. This will only need to be done where the top and bottom mounting blocks meet the rest of the assembly. Everything else is slid into place and is locked in without the need for glue or anything else.
This portion of the assembly once it has been put together will stand 14 1/4 inches tall and be 2 3/4 inches by 3 1/4 inches in size. After I have completed the assembly I will have to talk with my tech guys at the QC Co-Lab maker space in Davenport Iowa to help me out with the electronics and LED lights that will make this all work. Then on to the outer case. Lots of interesting things coming up in this project so I am glad to have this portion well on it's way to looking like something. I'll keep all of you up to date as I progress.