The Sherline Miniature Machinist's Newsletter
Customer Project of the Month
The following tip can be found on page 56 of Joe Martinís book, Tabletop Machining. If you donít already have the book, it is a great introduction to machining at the small end of the size scale and contains many interesting examples like the following from master ship modeler Phil Mattson. The book is Sherline Part Number 5301 and retails for $40.00.
Most kits come with a cast propeller that you file to final finish. If you are building a model from scratch, making a nice looking scale propeller can be a tough project unless you have a plan. Phil Mattson has made many of them, and hereís how he does it:
(1) A hub is turned on the lathe and left on the end of its piece of stock. The chuck is put onto the indexing attachment (or rotary table) and held on the mill. The headstock is offset to the angle of the desired pitch for your blades and a slot is cut for each blade. In this case it is a 4-bladed prop so the cuts are 90∞ apart.
(2) Four blade profiles are cut from sheet brass and filed to shape. The photo shows the hub and the four flat blades along with a finished prop.
(3) Each blade is placed on a block of hard rubber and a brass billet of the proper diameter is laid on top of it. The billet is hit with a hammer and the proper curve is bent in each blade. (Protect the billet stock with a block of wood so as not to dent it with the hammer.) The photo shows a flat blade on the rubber sheet and a finished blade on top of the billet.
(4) The hub is placed on the shaft and blades are soldered into each of the slots. As a final touch, the prop is polished to a mirror finish.
Many more Sherline projects can also be found on the Sherline web site at www.sherline.com/workshop.htm.
If you have a project that would be a good candidate for this newsletter, please send it to firstname.lastname@example.org.
Shop Tip of the Month
Eddie LaBane customizes pool cues and often has need to tap holes concentric to the center hole for this and other jobs. Using a tap by hand without a guide can allow it to cut at an angle putting the threads off center. Worse yet, small taps are easily broken if not kept perpendicular to the hole. Here is a simple tool he turned using his Sherline lathe. Eddie notes, ìMy purchase of the Sherline lathe has allowed me to create simple tools that improve the quality of my work with greater ease, and also to make tools that improve the versatility of my other non-Sherline power tools. It was a good investment.î
Making the tap guide
Out of frustration for a manual alignment tool for tapping the joint and collar of custom cue sticks, I decided to make my own that would rival a miniature lathe (I have two) if they were strong enough to do the job without major surgery. Here is the result:
1) The base of the unit is an aluminum washer 1.5" in diameter and 1/16" thick. The hole in the washer is enlarged to .501".
2) The center post is 1" diameter thermoset plastic 15/16" tall and 1" in diameter with a .500" center hole all the way through.
3) The center post is epoxied to the washer so that the center holes are perfectly aligned.
4) Using Plasti-Dip, spray coat the entire outer surface, including the bottom but not inside the hole. I applied four coats. This will make it easy to hold in your hand and prevent the unit from slipping on most surfaces.
5) Using a piece of hard (T6) aluminum, turn an insert or inserts .50" OD x 1" high for every commonly used tap.
6) Measure a popular tap at its widest thread point. Use this measurement plus .001" to determine the center hole that will be added to each aluminum insert. This allows the tap to move through the unit easily and will product a tapped hole superior to any I've seen done with other manual tools at any price.
NOTE: Additional inserts with properly sized holes are a must if you want to be able to get good results with each size tap.
(Left) The plastic body with aluminum washer base. Next to it is the aluminum guide insert. Right) The plastic body with one of the aluminum tap guide inserts in place, (Click on either photo to view a larger image.)
The guide block is seen with one of the inserts in place and one of another size next to its tap. The center hole is made .001" larger than the tap for a precise slip fit and good alignment with minimum play. (Click on photo to view a larger image.)
Using the tap alignment tool
The tap guide is held in place with the large base flat against the part being tapped. In this case the part is held in a vise. The sprayed-on surface finish provides plenty of grip to keep it from slipping. The tap is then threaded through the guide hole and run into the part. The guide keeps it cutting squarely. (Click on photo to view a larger image.)
You can see this and 67 other handy tips on the Sherline web site at www.sherline.com/pages/tips.htm.
Industrial slides and spindles for engineers, technicians and light production
This small CNC fixture to do multiple operations is an example of the kind of quick tooling you can put together with components from Sherline's regular and industrial line of components. Three tool posts hold different cutting tools or chucks while the DC motor driven, variable speed spindle with an ER-16 collet holds the part. Sherline offers manual and CNC slides, round, flat bottomed and dovetailed spindles and a variety of components to fit them. We do not make large fixtures, but if the movements you need are in the range of 14" or less and you want accuracy and repeatability at low cost, you've come to the right place. Click here for more views of the above fixture. PHOTO 2, PHOTO 3
A simple single-axis manual slide. It can be ordered with a table length of 8î, 13î or 18î and is also available with a stepper motor mount and motor for CNC control. See the Manual Slides page.
This 2-axis slide is based on the base of one of Sherlineís milling machines. It is set up in ìCNC-readyî configuration with motor mounts for application of NEMA 23 stepper motors. See the page on CNC-ready slides.
CNC-ready slides can also be ordered with motors and programmable CNC controllers.
Low Cost, Light Duty Precision Machine Slides for Small Jobs
Most precision slides are made in low quantities and are, therefore, quite expensive. Sherline Products Inc. has produced a line of precision miniature machine tools since 1974. Many of the components of the Sherline lathe and mill such as the spindle/motor/speed control and the machine slides lend themselves well for use as part of production tooling. For years we have seen people re-tasking all or part of Sherline machine tools to build specialized tooling from the components. Engineers, designers, prototype builders and inventors have found that there is no need to ìreinvent the wheelî when it comes to designing production components. Those who have discovered Sherline's components are impressed with the versatility, accuracy and low cost of the line. The industrial line takes our most popular machine tool slides and components and adds more versatility for use in general tooling applications. The modular nature of the components allows you to use them as kind of an ìEngineer's Erector Setî for your small tooling and motion needs. The phenomenal growth of both Sherline's tool line and the Internet have combined to offer a great opportunity for the designer.
The spindle selection includes flat bottomed headstocks and cartridge spindles with and without a flange. Pulley choices include toothed timing belt and 2-position V-belt pulleys. Spindle noses can be our standard æ-16 thread and #1 Morse internal taper for use with Sherline accessories or an ER-16 nose for use with popular ER-16 collets. Complete headstocks with DC motor and electronic speed control are also available. See the page on industrial spindles.
Two ways Sherline keeps costs so low on these components
One way is by producing items in quantity. We have invested a lot of time and tooling over the past several decades to develop and perfect our commercial tool line. We make our own chucks, handwheels, leadscrews, machine slides...everything needed to produce small lathes and mills. We purchase motors in quantity and have designed our own custom electronic speed control. During that time, we have been aware that many of our components were purchased by designers and engineers for use in special tooling, but the advertising cost of reaching such a disparate group was prohibitive.
The second way to keep cost down is by using the Internet to market our line. Most of our industrial customers in the past were those who were already aware of Sherline tools through their hobby interests. By marketing these components directly to customers by way of the Internet at http://www.sherlineIPD.com, we save the cost of advertising and the cost of printing and mailing an expensive color catalog. The industrial component line is directed toward customers who already know what they are looking for, know how to use it and also know a bargain when they see one. These savings in quantity purchasing and low advertising costs are passed on to the end user.
Customized for versatility and supported by a huge accessory line
Sherline's chucks, XY and XYZ bases and motor/speed control units have long been a popular source of components for machine design. Now we have taken those components and used them as the basis for a complete line of interrelated parts specifically for small industrial tooling design. We have beefed up some components and modified designs on others to make them usable in more ways. Bases have been redesigned to allow for easy attachment to flat material.
In addition, the Sherline tool line includes the world's largest selection of machining accessories made by a single machine tool manufacturer. That means you have a large choice of components such as vises, tool holders, chucks, collets and adapters that will fit the spindles and T-slots of the Sherline industrial components.
Even components as simple as a handwheel, leadscrew and nut assembly can be purchased to help you move a slide or fixture of your own design. Shown here is a handwheel that can be reset to a ìzeroî reading at any time. Plain handwheels are also available with 50 marks and inch threads or 100 marks and a metric thread. See the handwheels page.
What about size?
Our specialty has always been products near the smaller end of the size range. We do not make large parts. However, if you need to develop ways to produce precise position control over movements of about 4 to 13 inches or less, why pay for more capacity than you need? The versatility of our system is unmatched, and the low cost of our components will amaze you when you compare them to others now on the market.
Did you know?
ï If you were already aware of Sherlineís Industrial Products Division site, you might want to come back and visit it again soon. We are in the process of making it even more designer friendly by adding 3D .IGS format drawings of the most popular components. This will make it easier for designers to spec these components in their tooling designs.
ï Sherlineís web site includes a page that sums up most of the key dimensions and capacities of Sherline tools. See www.sherline.com/dimen.htm for a cutaway view of a lathe and lists of the most asked for dimensions and statistics.
ï If you have to call Sherline for a replacement part or for help with an adjustment, it saves everyone time if we are speaking the same language. By that we donít mean English, we mean ìmachine.î Each component on a lathe and mill has a proper name and it saves time for everyone if we both understand exactly which part we are talking about over the phone. See the Terminology page at http://www.sherline.com/terminology.htm for call-outs of all the major parts of the lathe and mill so we all are talking about the same thing. For example, instead of saying, ìThe square block thing on the flat part the movesî the process will go faster for everyone if you call it a ìtool post.î
ï In addition, if you have an exploded view parts diagram in front of you when you call it can save time too. Links to all of the machine exploded views can be found at http://www.sherline.com/exploded.htm.
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 craftsman added to on-line museumóDavid Glen has built a spectacular 1/5 scale model of the famous British Spitfire fighter from WWII. He is now well along on his 1/5 scale model of the P-51 Mustang of the same era. Learn more about David and see photos of his planes on his new page in the model makers section
In addition, a new opposed twin-cylinder engine built and donated by Ralph Cooney and a new-in-the-box Curta Type 1 mechanical calculator that belonged to Joe Martinís late partner Carl Hammons are now also on display. The family of the late Les Cade also kindly donated 8 more of his steam engines, which will be added to his collection now on display.
ï Club and Group VisitsóSeptember 15th saw a visit from members of
the local British Auto Club who were part of a charity weekend event to raise
money for Meals on Wheels. The
museum tour on Saturday was preceded by an exclusive tour of the Mercedes Benz
Design Studio in
On October 13th, the museum was visited by the Antique Car Club. Old Fords, Studebakers and even a rare Franklin graced our parking lot. See the Club Visits page for photos of some of the participants and their cars.