A Review of a Combo Lathe and Milling Head:
Why would I want one? - Page 8
Measurement — Good measuring instruments are required while making parts using any lathe or milling head machine. This import caliber from Mitutoyo provides for English, Metric and absolute measuring up to six inches (Photo 42). They are affordable and available from many tool supplier such as Travers Tool.
Photo 42 — As part of your time learning machining skills, you will need instruments for measuring your parts. Digital Calibers, such as this one from Mitutoyo, are not very expensive and sometimes are on sale at better suppliers such as Travers Tool.
Lubrication — To succeed in making parts, whether using a stand-alone or combo machine, you have to use lubrication. You will need to understand the functions of cutting oils and when to use certain products. Lubrication provides cooling, part quality and tool longevity (Photo 43).
Photo 43 — As mentioned, machining requires various methods of lubrication. Many products are available for specific metals. Take the time to understand them and when and how much to use. Depending on the material being machined, all that maybe needed is a few drops whereas harder materials may require constant (spray) lubrication.
It's important that you take some time to learn about some of the machining processes mentioned here. Older machining books found at yard sales, library sales racks or other places are great economical sources for the lathe (turning) and milling operations. Often, these resources are loaded with information on how to set up workpieces and the order of the steps necessary to achieve satisfactory results.
- Subscribe to the Home Shop Machinist. This is a great place to start to learn about this fascinating skill. Peruse the article index and notice the extensive list of training DVDs and books available.
- Acquire catalogs and sales circulars from some of the sources listed here (e.g. Travers Tool). Become familiar with the cutting tools and jigs needed to perform a task.
- The internet is a great source of videos and other instructional material on machining tasks. Take advantage of these resources and become familiar with the methods and details shown in those tutorials. Consider joining discussion forums for machinists. There are many experts out there that are willing to share their expertise...all you have to do is ask. If your considering the purchase of your first machine, ask the opinions of these experts about specific machines...maybe they have one and can offer insight into its quality.
- If (and hopefully when) you decide to plunge into the world of machining, establish a work area suitable for such work. When locating your machine, keep in mind that some cutting fluids and metal chips will fly out as the machine runs. A sturdy table capable of supporting 1,000 pounds will be needed. While your machine may weigh less, the momentum of some work pieces turning will need a sturdy work table. Machining in general usually includes tooling and accessories that are heavy. Consider including roll out drawers in your table design, but be sure to use heavy duty drawer hardware that allow for full length extension. Expect these drawers to hold a hundred pounds or more. The surface area should be large enough for the both the machine and resting small tools and accessories used when operating your machine. Locate your machine in an area where you can accommodate long lengths of stock since round and hex stock typically is sold in twelve foot lengths. Locating your machine with the lathe head against a wall will defeat the purpose of running long stock through the lathe's chuck. And don't forget to consider storage of your stock. As you work through your stock, you will accumulate quantities of miscellaneous sizes of stock, and it's useful to be able to keep them organized.
- Ample lighting should be considered when setting up your work area. Articulating swivel head (or goose neck) lights are quite helpful to direct light into an area.
- As you learn the practice of machining, imagine how a part can be machined. Ask yourself, "if I had to make this, what steps (and in what order) would I perform to make this part?" Apply this to the steps needed to the parts in this article.
- Machining involves purchasing equipment, tooling, and accessories. It's an investment which only you can justify based on the type of work you plan to perform on your machine. Protect your investment and set up in a good low humidity location.
Summary: At the time the author entered the machining trade, the Smithy 1220 XL was a machine offering good features at an attractive price for the hobbyist. The 1220 XL has provided an opportunity to learn basic and advanced machining practices while keeping the expenses to a minimum. Given today's choices amongst vendors, investing in a 3 in 1 combo is easier. Your choice will have to balance how much you're willing to invest for the projects you will be performing.
- Companies like Detroit Machine Tools and others offer different grades of their machines depending on the type of service required. Their Granite series offers improved precision and reliability and is heavier (650-800 pounds vs. 400-500 pounds of their Midas Series)
And some disadvantages of the 1220 XL unit covered here:
- Changing the Power Feed to perform turning at a selected Threads Per Inch (TPI) requires the operator to change a series of gears inside the cabinet. The instructions are good and the procedure is not complicated, but nonetheless it's an inconvenience. Higher quality units or stand alone lathes use a gear box with control knobs to select the needed TPI. Detroit Machine Tools now offers the Granite Series which includes a quick change gear box.
- There is no power table feed while operating the milling head. Since the table feed is connected to the lathe function, when the milling head is engaged, the power feed is disabled. Having a power feed feature is quite handy while making multiple light passes. Instead you have to manually crank the power feed screw to move the table (and hence the work piece). A power feed is now available on the Midas LTD models and the all Granite series models.
- Plan and understand accessories. The Smithy 1220 XL uses Morse Taper #3 interface for the milling head and tail stock. Look ahead. If you think you will out grow your "beginner machine", check to see if the accessories you purchase now will be interchangeable with your subsequent purchase. Some companies use Morse Taper #4 or R8/JT-3. Will the accessories bought now be usable in the future? Talk to the retailer/manufacturer. Knowing this in advance may help you decide which machine to choose.
Helpful References and Resources
The Home Shop Machinist, Since 1982, subscription magazine for home shop machinists by machinists.
- Machinery Values website for used machinery. This maybe overkill for the beginner, but provides useful info on many makes and models.
- Locator On Line is a website for used machinery. Provides useful info on many makes and models.
- On-line tutorial on a milling machine, useful info for the beginner.
- On-line tutorial on a Lathe, useful info for the beginner.
- Little Machine Shop is a premier source of tooling, parts, and accessories for bench top machinists. Useful for small milling and lathe tooling.
- Practical Machinist is an on-line resource for traditional and advanced machining processes. Includes a Discussion Forum.
- Travers Tool offers drills, mills, taps and dies, cutting tools and other accessories.
- Speedy Metals offers materials and caters to the hobbyist for small quantities.
- Metals Depot is a source for materials.
- On Line Metals is a source for materials.
- American Machinist is an on line resource for the Machining Industry.
- Sherline offers lathe, milling and tooling mainly for the model Hobbyist.
- Books: Machine Shop Practice, Volumes 1 and 2, Industrial Press Inc., 1981.