General News and Events
The last meeting was held on January 18th at the library. Nineteen people attended. George Edwards presided since John Korman was unable to attend. The meeting was very interesting with much of the discussion centered around Sterling Engines and our own club's Sterling project that is underway.
The next meeting will be on February 15th. This meeting is special because it will be held at Rutland Tool and Supply. Dave Adamek, the manager at Rutland, is providing hot-dogs and refreshments. This is definitely one meeting you will not want to miss.
Rutland Tool is located at 6605 Roxburg, Suite 100. This is near the intersection of SH290 and Little York Rd. See the map at the right. -->
Of Special Interest or "This Journal Needs Some Lube"
As always, we are desperately needing original articles to publish in this Journal. ( I am running out of ideas.) Please do not submit articles that have been published elsewhere unless you own the copyright. If you would like to submit an article, idea, or photograph, there are several ways this can be done. The best way to submit an article is in machine readable form. A plain text file is the easiest to work with. It can be placed on a floppy and mailed to my home, or attached to an Email and sent via the Internet. Articles and other ideas can also be faxed to my office at (713) 251-3860. This is a Spring number, and will be a toll call for most of you. If you have any photographs of projects, I would like to try to publish them here. If you have a scanner, send me the scanned image file in JPG or TIFF format over the Internet or via US mail. If you don't have a scanner, send the photo in the mail, or hand it to me at a meeting. I don't think the FAX will work well enough. If you don't have a usable photo of your project, give me a call and we'll shoot it on 4x5 Polaroid and make it look pretty. Also, mechanical drawings in DXF, WMF, CGM, or AutoCAD DWG are easy to put into the newsletter.
Membership is open to all those interested in machining metal and tinkering with machines. We currently have members that have considerable backgrounds in the hobby, and other members that are just starting. The purpose of the club is to provide a forum for the exchanging of ideas and information. This includes, to a large degree, education in the art of machine tools and practices. There is a severe shortage of written information that a beginning hobbyist can use. This makes an organization such as this even more important. Please send in your dues to help keep this club in sound financial shape and continue to help more people get into this fascinating hobby. For membership information and forms, call John Korman at (713) 723-8597.
First Impressions (IMHO)
I recently had a requirement for machining several very small parts. Although my 12" lathe is certainly capable of producing small parts, it is not much fun to work on 0.062" diameter parts with a 6" chuck spinning in your face. Also, I am hesitant to run the lathe at the high RPM required for long periods of time. This can't be good for the bearings and gear head.
Rutland had a sale on the Sherline lathes, so I bought one. These are very small machines, mine has a 3.5" swing and 8" between centers. This article is the result of my first impressions on using this machine.
The model I bought is a 4000A. It comes in a box only 8" square and 21" long weighing in at about 25 pounds. The people at Rutland were very nice and helped load the machine in the truck, even though I insisted I could do it myself.
I must say that I was very impressed by the quality of the construction of the tool. Fit and finish was very good. The documentation was also well done. Although most of the lathe is aluminum, the bed is made from steel ground into a single set of dovetail ways. Something like a Hardinge. The lathe runs smoothly all the way up to 3000 RPM. The motor is a DC type, with a very nice speed controller that does a good job of maintaining torque even at the lower RPM's. It does not have a reversing switch. Installing one would be easy, I just need to check-out the brush geometry to make sure the motor is designed to run either direction.
Again, the lathe is very well constructed, but it has, to my way of thinking, some design flaws. For the most part I like the machine, but, I have a few things that I would like to have changed.
The thread cutting kit, that is optional , requires that the motor be removed while cutting threads. This is because the motor is mounted behind and to the left of the head. Although I do not yet have the threading kit, I do plan to purchase one. I wish the motor was mounted directly behind and above the head. This would allow the operation of the change gears without removing the motor. This may, however, restrict the amount of rotation that can be used on the headstock. One method of cutting tapers on this lathe is to remove an alignment key and rotate the headstock toward the front or back. This may sound neat, but rather than mess with headstock alignment, I think I'll just shell-out $70.00 for a compound slide.
The other main problem I see with this lathe is the tailstock. The first, and most obvious, problem is the lack of sufficient travel in the tailstock quill. Since the tailstock does not have the ability to "over-hang" the cross-slide, it is impossible to turn from the tailstock center to the headstock with a single tool setting. This is also complicated by the fact that the cross-slide can not be moved under the faceplate or chuck. I am afraid I will soon end up with "smiles" on the headstock side of my cross slide in a short time. The quill uses a #0 Morse taper, for which good tooling is very hard to find. Finally, the groove cut into the side of the quill to prevent it from turning is also used to lock it down. The tip of the lock-down screw rides in this slot. The quill should use a split cotter or quill housing for lock-down. The makes quite a difference if you are trying to do precision work. Because the lock-down screw is on the front side of the tailstock, it pushes the quill to the rear when tightened. This is the worst case when turning between centers. If the screw was at the top, and pressed down, the result would be less apparent. Incidentally, the tailstock can not be removed without first removing the carriage feed handle on the right end of the lathe.
This will be a good project. Find a way to remount the motor in a handy manner, and, design and build a heavier tailstock. One with a #1 Morse, good quill lock, overhang, and easy to remove and get out of the way.
All in all, I don't want to leave the impression that the Sherline is a bad piece of equipment, on the contrary, I think it is well built and will be a valuable addition to my shop. I would caution, however, the Sherline is a good secondary machine for the shop, I would never want it to be the only lathe. The Grizzly 9x18 or other similar lathe is much more versatile a better choice for a first lathe.
Read a few good books lately?
Model Making, by Raymond Yates
This is a reprint of a book first published in 1919 and 1925. There are a lot of reprints out there whose usefulness is mostly limited to nostalgia. This book is not one of those. Although the chapters on lathe work and drilling may be dated, the rest of the book is filled with lots of good information and ideas for machining and model making. There are at least two dozen construction projects dealing with both steam and IC engines. One chapter deals with a steam powered hydroplane that will go in excess of thirty MPH! Another chapter details the construction of a four cylinder radial steam engine and flash boiler. The engine is small enough and light enough for a model airplane, yet puts out 2.5 horsepower. A very interesting book indeed. The book is available for $14.95 from Lindsay Publications.
Basic Machining Reference Handbook by Arthur R. Meyers & Thomas J. Slattery
Looking at the title, one would think this book is just a list of data and tables, like The Machinist Handbook. Actually it is a good concise tutorial of the operations done in a small machine shop. The first chapter covers the principles of measurement. Succeeding chapters cover Cut-off, Lathe operation, Milling Machine, Drilling, and Grinding. The last chapter is a simple introduction to CNC machining. One of the interesting aspects of this book is that it does a good job covering the Vertical Mill. It is written not as a text, but more as a refresher course. It is concise and to the point, not wordy like my ramblings. A good, easy reading book for the beginner or advanced machinist. Industrial Press Inc., $29.95 at Brown Book Shop.
The Double Scotch
In browsing through my copy of Elmer's Engines, by Elmer Verburg, I ran across a steam engine he named "Scotty". This engine used a scotch yoke to translate the reciprocating motion, of the piston to the rotary motion of the output shaft. The engine had a one single acting horizontal cylinder. A sliding support was necessary at the opposite end of the connecting rod from the piston. Another feature was that the crank-shaft was used as a rotary valve. A neat little engine, but we need MORE POWER. Instead of using a support for the connecting rod, this design uses another piston and cylinder. In place of the rotary valve, my design uses a spool valve driven by another scotch yoke. Two scotch yokes, one converting reciprocating to rotary, the second convert rotary to reciprocating, hence the name "Double Scotch". The engine is very smooth and will run on air as low as 1 PSI. The Double Scotch is fully described in the Projects section of this web site.
The Sterling Engine Project
Don Foster has been corresponding with Jerry Howell, the designer of the "Miser" Sterling Cycle engine. Jerry has returned a quotation for partial materials kits and plans. Since we already have eight members signed up to buy the kits and plans, our price will be $12.00 each for the plans and $14.00 each for the materials. I think this is a very good deal.
Don feels that the design is a good one and we should all be able to build engines that work well. The "Miser" is a low temperature Sterling engine that is supposed to be able to run off ice cubes or the warmth of a hand. At the next meeting, Don will collect commitments and/or money for the kits. When everybody gets theirs built, maybe we could have a Miser "Run-Off".
Coming-up in March
I have been intending for some time to do a newsletter on the theme of Workholding. A large part for machining is just trying to figure out how to hold the workpiece. Methods such as using jigs, fixtures and soft solder will be covered. Also, the design of special vise jaws and clamping attachments will be discussed. If you have any favorite or clever method to hold and machine parts, let me know and I'll get it in the issue.
A couple of days ago I received a call from a person at J&L Industrial Supply in Livonia, Michigan. They will be opening a store in Houston on February 10th. The store will be located at 13230 Hempstead Hwy. I believe this should be right around the corner from Wholesale Tools. Be Careful in the Shop and Keep Those Chips Flying I have dealt with J&L on a few occasions, and they have always provided very good service.
Answer to last month's Crossword Puzzle
Don't Forget The Next Meeting !!
Meetings are held at the Oak Forest Library on the third Saturday of the month. The meetings start at 1:00 PM.
Our next meeting is scheduled for February 15th.
This meeting will be at Rutland Tool.
See the announcement inside. Bring in a project you've been working on.