Intro: Lathe Turned Plastic Bowl
I found a bunch of this plastic in different shapes and sizes. Im not sure what the technical name for it is, but I have seen it used in many jigs at machine shops. I posted a forum topic questioning what it is here.
I had to try making a bowl.
Step 1: Chuck It Up on Your Lathe
This piece already had a perfect recess for my chuck. :-D
I mounted it and got it slightly round then went to work on the inside of the bowl.
Step 2: Hollow Out the Inside of the Bowl
Move your tool rest to the proper distance/height to start removing material from the inside of the bowl.
I start most of my bowls by using a 1/4" drill bit in the center. Tape off the correct depth (the depth of the inside of your bowl) on the bit and using your tailstock drill chuck drill the hole. This gives you an accurate stopping point while hollowing.
I used a home made Carbide tipped finishing tool.
This stuff cuts nice. It seems easier to control at lower speeds but the higher speed gives the best finished cut, so mix it up a bit but be careful... When it does snag, it will whip the hell outta your hand at 1200 RPM. Not fun!
Step 3: Shape the Outside
Move your toolrest back to the outside and start shaping the outside the way you want...
I could have been a little less wasteful here, but I plan on making the leftover chunk into a lid for this.
Take your time here... While cutting you will get a nice ribbon shooting off toward your shoulder. This ribbon is on single continuous strand if you are holding the tool properly and it is sharp. This is what you want, one long ribbon like strand. but beware. that one long continuous ribbon will quickly snag and pull every bit of the ribbon back around the workpiece making a birds-nest looking mess wrapped tightly around the middle. so stop and remove this stuff often from your workbench and area. It will pick it up!!!
Take your time and go slow...
Once you get the proper shape of the outside, you may want to go back and thin it a bit on the inside. This is also a good tim to raise the speed and finish cut it... Do this for inside and outside of the bowl.
Step 4: Sand Your Work Piece!
Its the same sanding procedure as wood... start with around 80 or 150 grit and work your way up to at least 800.
It sands like an extremely hard wood, so again, take your time and go slow. The workpiece will get warm and even hot from the friction of sanding so let it cool down and check that your chuck is tightly holding your work often...
you could wetsand it further for a better finish, but i was happy with what i had....
Step 5: Polish It and Part It Off
I used a plastic polish and wax... its done. The wife loves it and once again took it from me! It has a nice translucence to it with a candle..
Thanks for looking