By popular demand, we are including some photos of projects that are really too big to be made on Sherline tools. If a potential customer were to ask if this operation could be done, we would say "No, you need a bigger machine". But modelers among the most resourceful craftsmen in the world, and many find it a challenge to make things that everyone else said couldn't be done. The people setting up these operations are experts with their tools and know how to get more out of them than was ever intended and still get good results. This page is in no way intended as a recommendation for setups like this, but if you use small tools and occasionally run into a part that is a bit too large but needs to be done anyway, perhaps some of these setups will give you some ideas of how to accomplish the impossible.
NOTE: For those who would like to see a good movie that represents the attitude involved here, I recommend going to the video store and renting "Flight of the Phoenix". If ever a movie represents what can be done by a good modeler, that one is the best. It is about a cargo plane that crash lands in the desert. The only way out is to rebuild the wreck into a smaller plane that can fly them out using one engine and the parts and tools at hand. The "engineer" who directs the process turns out to have only built models before, but his modifications work. Even if you've already seen it, it's worth watching again.
Charlie Lear recently ran a little experiment to see how large a part he could turn using a mill instead of a lathe. Check out his web page at http://steammachine.com/millturn for the results.
To display his tiny steam engine models at shows, Jerry wanted to protect them from curious hands while still making them easy to see. He designed an oak case with an angled glass front and glass top. He decided to add to the challenge by making it on the same tools he used to make the models displayed within. Despite the availability of larger woodworking tools, Jerry took on this project just for the fun and challenge of it. Obviously it took a lot longer to do this way, but when you are doing a project for pleasure and not for profit, sometimes taking the long way around can add to the satisfaction. There is a picture of Jerry with the finished display case on page 325 of Joe Martin's book Tabletop Machining. If I can find the original picture, I will scan it and add it to this page later.
Cutting a 12" wide by 3/8" thick solid oak plank with a slitting saw
Machining the angles on the corner of the framework
Sanding the top of the display case panel
Polishing the edge of the display case front glass panel
NOTE: More about making wooden finger-jointed display boxes on small machine tools is covered in the special "Common Threads" edition of Home Shop Machinist published in November, 2001.
Pete is a Sherline employee who maintains our large factory equipment. He is also an excellent race car mechanic and machinist on all size tools. At home, he uses Sherline tools to work on his model trains and to build gas and steam engines. He is currently building a running scale model of a Porsche flat six racing engine, some photos of which are included in Joe Martin's book, Tabletop Machining. The castings shown below are from a steam engine casting kit that is far too large to be made on Sherline tools, but Pete wanted to see if he could do it.
Finishing the outer edge and back edge of a large wheel. The headstock is lifted using a riser block to get an additional 1.25" clearance. By turning the headstock at a 45° angle and using the compound slide at a 45° angle with a cutting tool also angled at 45°, Pete was able to finish the outside and back faces.
The gear teeth are being cut into the wheel using an involute gear cutter on a long arbor. The wheel just clears the table using the standard vertical rotary table setup. A chuck mounted to the rotary table holds an arbor that secures the wheel by its center hole. The small closeup shows the nice tooth form.
This casting is huge for a machine of this size, but an oversize tooling plate was designed to hold it. Several step block clamps are used to hold the casting down while an inserted tip carbide fly cutter is used to flatten a surface.
Mark Jones has enclosed photos of the setup he used to cut large aluminum gears for the azimuth of a amateur-made 10' binocular telescope. Normally, the 4" rotary table in the vertical position can handle a gear blank that is slightly larger than the 4" table, but that's about it. Even so, that's a pretty big gear for a machine this size. Mark, however, needed to cut some REALLY BIG gears, so he figured out a way to do it with the equipment he had on hand...a Sherline CNC mill.
Here is a photo that pushes even this extreme setup to its limits--a 14" diameter aluminum gear being cut in the same manner. (Click on any of the above photos to open a larger version of the image.)
Return to Sherline's Home Page