CAMS Review of 25 April 2002 Meeting

CAMS

Chesapeake Area Metalworking Society

Review of 25 April 2002 Meeting
Fairland Public Library
14910 Old Columbia Pike
Burtonsville, MD

under construction

Chesapeake Area Chesapeake Area Metalworking Society Review of April 25, 2002, Meeting

Fairland Public Library

14910 Old Columbia Pike

Burtonsville, MD

Roy Schaffer acted as "den mother" for a moderate turnout of a dozen-and-a-half or so CAMS members.

Roy kicked things off by showing a right-angle Vee block (i.e., with two Vee's machined at a 90-degree angle to each other). This artifact was exhibited for the particular benefit of Tom Hubin, who will need something like this for machining an optical mirror holder that he is planning.

Dave Bluett showed us the produce of one of his recent scrapyard visits. Copper balls of about two-inch diameter, of which Dave secured about 25 good machined ones from a five-gallon bucket load.

Dave's show-and-tell prompted Chris Helgesen to share with us a "copper anecdote" from the days when he worked in a laser lab: One of the lab's projects required that lasers shoot their beams into the windows of a four-foot diameter stainless steel sphere at a deuterium target. Prior to "shooting," this target was chilled by a cryoshroud, a tapered copper tube with circular cutouts, with an interconnected series of passages for liquid helium which were made by drilling and plugging a great many holes. This shroud would sit around the target, until it was pulled away by a powerful linear motor in a matter of nanoseconds before the lasers were triggered. The lab had one primary cryoshroud and two backup units--each of which had taken around 120 tries to make correctly!

While we were thus engrossed in the discussion of machined metal balls, Roy related how steel balls were used in the Lehigh Valley cement industry in the "raw mill" process to ball mill cement rock.

Chris took to the floor again to show an iron casting that he had procured from a neighbor as part of a wood lathe deal. Chris asked if anyone could identify the casting, which bore Part Number 1025.

Chris also showed a kit of Starrett indicator accessories which included two rocker arms for transferring motion to the plunger in right-angle and 180-degree (or is it zero-degree?) setups.

Finally, Chris asked the group for design hints and ideas for making a tooling tray (primarily to hold collets) for his lathe headstock area.

John Webb showed a VERY nice toolmaker's vise that he had made. John related that when he had shown the vise at an earlier meeting, he was asked if he had made any sketches or drawings of his design. At that time he had not, but he rose to the challenge with his special "handcad" process, and produced a measured sketch, copies of which he distributed to all present.

John went on to show a heavy-duty Lassy brand precision tap and die holder suitable for use in a lathe tailstock or a vertical milling machine spindle. John has made inserts to hold each size of die that he usually uses in his shop.

John also showed a clever slitting saw holder that he had made that uses a drawbar to secure the saw blade, thus allowing the saw to work close to the vise.

In response to a request by a CAMS-er who wanted to know more about drill bit sharpening, Rich Kuzmack brought and demonstrated the use of a Lisle (pronounced "Lyle") sharpener. Not for the micro-machinist, this rig will sharpen bits from one-eighth inch through one-and-one-quarter inch.

Fred Schirrmacher shared a tip for making containers for small (below number 60) drill bits: Recycle BIC pens by cutting the body tube to length and plugging one end with epoxy.

The group engaged in a discussion of the downside of using lubricants (such as WD-40) sprayed under pressure. When the propellant expands, it produces a cooling effect which, under proper conditions of temperature and humidity, tends to foster condensation on the surface being sprayed. This can be counterproductive when the lubricant is being applied to prevent oxidization.

Jerry Tuwiner showed a die filer that he made from a Metal Lathe Accessories kit of iron castings that he purchased at Cabin Fever (only three months earlier this year!). Of particular interest was Jerry's discussion of how he made files for the machine by shortening hand files, grinding down a shank, then fitting the shank into a steel collar with epoxy. (Recall that hand files cut on the "push" stroke; Jerry had to grind the new shank into the teeth of the former tip in order to produce a file that would cut on the "pull" stroke for his filer.)

Tom Hubin brought some positioning components that he had procured and discussed his precision optical mirror mount project. This prompted a lively discussion by the group about the best way to machine a cube of aluminum into an octagon on a Sherline milling machine.

Ed Moninger concluded the show-and-tell session by showing his Phase II brand small vertical/horizontal rotary table. No more than four or five inches square, it prompted feelings of "I want one!" from the small machine tool operators in the group.