The Sherline Miniature Machinist's Newsletter
Customer Project of the Month
Stop Motion Dog/Tom Brierton
Though most animated cartoons
are now computer generated, before that technology existed, each frame was
individually hand drawn or photographed. A popular form of animation was done
with clay models that were moved a little bit at a time and photographed at
each stage to get the appearance of motion. ìClay-mationî required talent, time
and a good, solid moveable matrix under the clay that could be manipulated to
move in stages like the real being it represented. Shown here is the framework
for a dog that Tom Brierton from
You can see more workshop projects on the Sherline web site at www.sherline.com/workshop.htm.
Inexpensive protection from chips and coolant for your DRO box /Tom Wheless
For many years, bailing wire was the farmer's universal remedy for securing anything loose. Then Duct Tape became the universal repair material. Now people are finding all kinds of uses for ZipLocÆ bags and not just in the kitchen. Campers and travelers find them handy for keeping electronics and matches dry or keeping liquids contained in case a container should leak in your suitcase. Anything electronic doesn't benefit from the machining environment, particularly near a mill that tends to throw coolant and chips in all directions. You want your DRO readout box close by so you can easily zero the axes when necessary and read the handwheel position and RPM displays, but you also want to keep it protected. Here is a simple, cheap solution.
While not overly elegant, this is a readily available, inexpensive and practical solution to keeping your DRO box clean. (Click on photo to view a larger image.)
ìI recently bought a Sherline DRO to accompany my Sherline manual lathe. I love the DRO and the additional precision and functionality it adds, but, as a retired electrical engineer, I worried about oil droplets and small metal bits migrating into the switches and connectors of the DRO and causing problems over time. So, I noticed a ZiplocÆ quart-sized heavy-duty freezer bag (dimensions: 8 x 7 inches or 200 x 180mm) would fit perfectly over the DRO box, and, kept partially closed with a small binder clip would still allow the wires to exit from the side. The plastic is transparent enough that I could still see the display and switches easily enough, and, when the plastic eventually becomes scratched, dirty or worn, I can easily replace the plastic bag for a few cents. See the photo above to see how the setup looks on my bench.î
óTom Wheless, Eagle, ID
To view this and 70 other shop tips for Sherline machinists see the TIPS page.
The P/N 3052 fly cutter comes with a brazed tip carbide tool and cuts about a 2" path. The #1 Morse taper is held in the headstock with an included drawbolt with special washer.
The P/N 7620 carbide insert fly cutter features a replaceable carbide insert with two cutting surfaces and can cut a path about 1-1/8" wide. A special wrench and attachment screw are included along with the drawbolt.
About Fly CuttersóFly cutters offer a great way to machine a flat surface and are the most economical way to remove material on the mill. They also leave an excellent surface finish. The cutter actually exerts less stress on the machine than you might expect. This is because it ìpeelsî the material off with little crushing action. If possible the cutter should swing a path wider than the material. If the material is wider than the cutting path, progressive cuts should overlap by about 1/3 of the previous cut. When using a fly cutter it is imperative that the part be securely mounted to the table. Also, note that chips coming off the part are HOT! A long sleeve shirt and eye protection are a must.
Standard Fly CutteróThe P/N 3052 fly cutter comes with a brazed tip º" tool, but there is no reason an easily sharpened high speed steel tool couldnít be used for many operations. A normal depth of cut in aluminum would be about .010" (.25mm) deep.
Inserted Tip Fly CutteróThe P/N 7620 fly cutter offers a good compromise between an end mill and a standard fly cutter. End mills are slow to remove a lot of material, but you can cut to a shoulder. A standard fly cutter is good at cutting an entire surface. The inserted tip cutter can cover a much wider area than an end mill but can still cut to a 90∞ shoulder. For non-ferrous materials the depth of cut can be .020" (.5mm). The spindle should run at maximum speed (2800 RPM) and the tool is fed fast enough that it is continuously cutting. A common beginner error is to not feed fast enough. Each cut should peel off a curly chipóand remember it will be a HOT one. For cutting steels, the RPM should be between Ω and full speed and a starting place for depth of cut would be .015" (.38mm). Back off the depth of cut if vibration seems excessive.
You should be able to obtain a good finish with this type of cutter. If you canít, try increasing the RPM if not already at full speed. A small amount of cutting oil will also help keep the chip from sticking to the cutter. Higher RPM also has this same effect, which is the reason for using higher RPM with carbide tools. Use of carbide inserts speeds up the process by eliminating the time spent re-sharpening conventional tools when working with hard-to-machine materials.
Additional carbide inserts can be ordered as P/N 7622 for $15.52 each.
Read the full instructions for the 3052 fly cutter.
Read the full instructions for the 7620 fly cutter.
Did you know?
ï When Sherline tools were first
sold in the
ï Videos of cutsóTo see and hear a Sherline lathe in action cutting materials from Delrin and maple to stainless steel and titanium see the video link at the top of the home page or CLICK HERE. The cutting speed and feed rate for each cut is listed. This is a good way for a beginner to get a feel for a starting place when cutting various materials.
ï Can you use your DRO on a CNC machine?óYes. The DRO handwheels can be relocated to the rear shaft of a stepper motor if you decide to upgrade your DRO-equipped machine to computer control. The DRO does not interface electronically with the CNC driver box, but it does give you a cross-check on the operation of the CNC as well as retaining DRO function when using the machine manually. You also get the benefit of a continuous readout of your spindle RPM. CLICK HERE for instructions on how to make the conversion.
Upcoming Model Engineering Shows
ï Cabin Fever Expo,
ï North American Model Engineering Society Expo (NAMES),
Send us your show details and we will post them hereÖ
Joe Martin Craftsmanship Foundation News
ï New Museum DisplaysóA digital slide show has been added to the display on Founder Joe Martin. It includes photos of his early days in Radio Control flying, products he has developed over the years and some of his other activities like sailing and sports car racing.
ï DonationsóA large collection of Model Engineer magazines along with some lesser known but interesting publications like The Model Maker, Ship Modeler and Steamboats †were contributed by William B. Barker.
ï Groups Visiting the Museum
óThis past month has seen two
special groups tour the
26th: Volunteers from the City of
9th: The San Diego Ship
Modelerís Guild had about 10 members stop by for a tour. Ship models are
featured in the
The museum is mentioned in this month's
Anyone interested in volunteering your services at the museum, please contact firstname.lastname@example.org or call 760-727-5857 and ask for Craig.