RUG/Pennsylvania/State College/Hot Tip
Hot Tip Projects
Penn State has decided to design and manufacture their own hot extruding tips. We are currently manufacturing .5mm tips and .35mm tips. We are hoping to get .25mm tips into manufacturing in the near future. This page is to keep update information on hot tip production and a place for future students working on hot tips to learn how to make them.
Below are the solidwork files as well as the drawing for the hot tip.
We are currently doing a combination of manual milling and CNC milling. For the .25mm tips we tried to manually mill the hole; however the machine was not precise enough to create a centered hole without breaking the bits. We used the FAME lab and a HASS turning center to create the front part of the brass piece, and manually turned the other parts.
Step by step instructions will be posted up shortly.
11.30.12 (In Progress) - We are currently working on redesigning the steel tip to include a smaller teflon piping to allow more space for the threads screwing into the hot plate. Updated solidworks drawings will be added when complete. With a smaller sized hole, we are working inserting a aluminum oxide rod to allow for higher temperature melting.
General Terms and Descriptions:
Axes: y axis - forward/ backward. Axis measurements to .001 inches (one mil). x axis- left/right. Big wheel.
compound axis- Adjustable angle axis. This will be used for threading and for cutting the cone on the brass part.
Gears: We use high gear and low gear. Low gear is for threading only, and high gear is for any other type of cutting. A demonstration of this should be done in person. Change gears only when the lathe is off, and change speed only when it is on.
Threading should be done at 80 RPM. For brass, cutting is done at 500 RPM. For steel, cutting is done at 500 RPM.
Tools: This refers to the different cutting tips that go on the lathe. There are four that we use: facing, for cutting a flat side; turning, for reducing the diameter; threading, for cutting threads; and grooving, for cutting a groove. There is also a drill, which is separate from these tools.
Mil: This is a unit of measure, equal to .001 inches. This is what everything will be measured in.
BE SAFE. DON’T BE STUPID.
If you have any questions, don’t hesitate to ask a TA. They are pretty helpful, and they all know what they are doing.
Before you do anything, think through it. From experience, it is really easy to ruin your part, and this can be avoided by not making any silly mistakes. Make sure you are familiar with the operation of the lathe before you use it.
Some Tips and Tricks:
● When you are cutting threading, the best way to check if you are done is screw the threads into another part. Use emery cloth to sand down the threads a little bit. If you are worried about cutting to deep (especially on the steel part), you can finish the threads with a die. However, this is only for cleaning up and finishing the threads, not cutting them entirely.
● When tapping or drilling, be very liberal with the cutting fluid, and use it frequently. If something starts smoking, back out the bit and give it a minute to rest.
● Use your calipers early and often. It’s really easy to mess up the part because you didn’t measure something correctly the first time.