Product Review: Grizzly 4003G metal gunsmith lathe

I recently bought a Grizzly 4003G lathe, which has proven to be a very useful tool in my shop and a major upgrade from my previous lathe. The 4003G is a great value, and I would definitely recommend it for anyone looking for a 12x36 lathe for hobby or semi-pro work.

Shop lighting upgrade: T5 vs T8 fluorescent vs LED

I am in the process of upgrading the lighting in my shop. It currently has a number of 4-lamp and 2-lamp T12 4-foot fluorescent fixtures. The best solution is to replace the ballast in each of these fixtures with high-efficiency electronic ballast ($15), and replace the lamps with T8 high-CRI bulbs. This will save energy, and greatly improve the quality of the light. LEDs and T5 fluorescent are MUCH more expensive to install, and their energy savings are not nearly enough to justify the cost. Most LED systems actually use more energy than T5 or T8. Remember that running a T8 with an electronic ballast will provide more light than it's nominal rating, which is for magnetic ballasts. T5 are always rated for electronic ballasts, so it is not a fair comparison.

For new fixtures in my shop, the cheapest/best solution is to buy $10 "shop lights" and replace the ballast. The total fixture cost is $25, and efficiency is 96 lumens/watt for a total output of almost 6000 lumens. It can't be beat! Commercially-available T8 fixtures with electronic ballasts are more expensive, and the quality of the ballast is suspect.

Interactive model of a 3D printer for teaching

I built a simple working model of a 3D printer for demonstration at a school. My intention is to show the students how 3D printers work at their most basic level. The model provides a hands-on activity and can create alphabetic letters or other small souvenirs that the kids can take with them.

DIY Scanning Electron Microscope - Image Quality Improvements 3

A generous benefactor donated some proper SEM apertures to my project. These are much thinner than my brass plate in which I drilled a hole. This should increase resolution as there will be less scattering from the edges of my original, thick aperture plate









The main problem that I am having is that the oscilloscope X and Y amplifiers do not provide enough range or offset to easily control where the scan pattern hits the sample. I knew this would be a problem, so I included small mechanical X and Y stages for the specimen in the microscope. I even designed a vacuum-safe rotary passthrough into the vaccum chamber. The biggest problem is just connecting the rotary passthrough to the stage itself with a right-angle and/or flexible shaft arrangement. Space is very tight and the shaft must move with the stage, making for a difficult mechanical design.

How to design a transistor circuit that controls low-power devices (tutorial)

I describe how to design a simple transistor circuit that will allow microcontrollers or other small signal sources to control low-power actuators such as solenoid valves, motors, etc.