GCode for Chess Pieces

I made a few sets on a hydraulic tracer lathe when I was in college. I don't suppose that helps you, but it sure was fun.

Write your own damned code...

======================== If you can supply some more information it would be helpful.

(1) Do you want to make the entire 32 piece chess set or just selected pieces such as the king or knight?

(2) How large are the pieces you want to make? Typically specified by the height/base of the queen.

(3) What materials are you planning on using?

(4) Is this a "one off" or you planning for semi-series production?

(5) Does your v-mill have a rotary table [a axis] or are you going to generate the curves using xy moves? If a rotary table, is the vertical or horizontal? Does your controller support G2/G3 arcs or only G1? Is your controller 2_1/2 or 3 d?

(6) The "standard" chess set is generally assumed to be the Staunton. This was developed for easy turning in wood on a manual lathe with some manual second operations such as the crenelations on the rook, slotting the bishop, and sculpting the knight's [horses head] after the profile was turned. Given that the process and most likely the material is very different, you may wish to consider a chess set designed for CNC machining center [mill] production.

(7) Before I retired, I taught some basic CNC classes. We used a Denford ORAC cnc lathe. In the ORAC instructional material was a program for the queen and a pawn. Denford USA email includes snipped-for-privacy@denford.com snipped-for-privacy@denford.com snipped-for-privacy@denford.com snipped-for-privacy@denford.com They may be able to supply you with a copy of the printed documentation. Be advised that the ORAC G/M codes are not in standard format and will most likely required re inputting/translitteration for your controller.

(8) Do you have access to a CAD program? If so, can you read/save dwg or dxf files? If you can run Autocad LISP macros, there are a number of free macros that use the snap commands to locate, and will generate a leader line with the xy or xyz coordinates such as the centers/endpoints of arcs, arc radius, endpoints of lines that will make manual cnc programming the proverbial "piece of cake."

(9) If you are going to make several pieces, fixturing may be a bigger challenge than the programming.

(10) for chess sets see:

Unka George (George McDuffee)

There is something to be said for government by a great aristocracy which has furnished leaders to the nation in peace and war for generations; even a democrat like myself must admit this. But there is absolutely nothing to be said for government by a plutocracy, for government by men very powerful in certain lines and gifted with the "money touch," but with ideals which in their essence are merely those of so many glorified pawnbrokers.

Theodore Roosevelt (1858-1919), U.S. Republican (later Progressive) politician, president. Letter, 15 Nov. 1913.

Looks like we still have a few knuckle draggers around...lol And I'm a newbie just starting out..

Thanks for the info I'm glad there are few good machinist still out there to help us hobbist. I have access to a Hitachi Seiki CA250 if I can get the Fanuc error 930 on the controller reset. Wanted to make a couple of large Chess pieces for a Salt and Pepper shakers as X-mas gifts. I plan on Alum

generations;

glorified pawnbrokers.

politician, president. Letter, 15 Nov. 1913.

"BoxMaker" wrote in news:6Jy4g.70835 $ snipped-for-privacy@newssvr13.news.prodigy.com:

Sounds like you need a new motherboard. IIRC, a 930 alarm means the CPU is forked.

Oh.......well then this one takes the cake...

Mr. Rodgers then must ask:

"Can you spell 'expensive toys'"....

"PrecisionMechanicaL" wrote in news:e2ur1v$921$ snipped-for-privacy@emma.aioe.org:

It's all fun and games until someone puts an eye out.

Or a board.

===========================================

Several thoughts:

(1) large as in what diameter of base and how high/tall.

(2) Unless you are going for ornate pieces rather than the standard stauton pattern, this is far more of a lathe than mill/machining center project, although it can be done.

(3) Which particular chess piece(s) are you thinking of machining? For the internal volume, the rook/castle would seem to be the best choice.

(4) Do you have access to a lathe to drill/machine out the large center cavity, and tap the bottom?

(5) Given the wide use of aluminum in cook ware, I doubt that the amount of aluminum you might pick up from the salt shakers would add any significant risk, assuming one exists.

(6) Because the plugs in the bottom of salt/pepper shapers always seem to get lost over time, and because of the thread gauling factor, your best bet would appear to be to use a course standard thread such an NPT and use a plastic pipe plug for the closure. While these can be difficult to find, these are available in NPTS [short] configuration with several types of drives hex / slot ]. These are frequently used as shipping seals, so you may be able to get a few at an equipment dealer.

(7) If you must machine the shakers completely on the CA250 what is the vertical travel and maximum distance from the spindle nose to the table?

(8) What fixturing and tools do you have available? For example, do you have a helical thread mill tool?

(9) What is the largest tool the spindle/tool holder the CA250 will accept, and what is the biggest collet you have?

(10) It is likely that the fixturing and sequence of operations will be more of a challenge than the actual marching of the shakers, and is likely to take 3 or 4 times as long.

(11) Without knowing more about the size of the shakers and the vertical travel/space of the machining center, I envision a process something like this

(a) Cut shaker to stock to approximate length.

(b) Use large v-block bolted to table to blank is vertical, and face off.

(c) Reverse blank in above setup and machine to exact length.

(d) Pick up center of blank and machine salt cavity, tap for NPTS thread using your choice of tap guide/tap, thread mill etc.

(e) Reverse blank in above set up, drill "P" for pepper or "S" for salt in top. Assuming that your are doing the rook/castle, change from a drill to an end mill, counterbore the top and mill the crenelations.

(f) Thread blank onto arbor/spud. Generally is not a good idea to rely on threads for accurate positioning, so you may have a stepped arbor where the location is from the bore and the threads are only to hold the blank on the arbor. You may want to use a strap wrench to avoid surface damage.

(g) Clamp the arbor/spud in the CA250 spindle/tool holder. Shank of arbor/spud should be as large as will fit. At this point you will be using the Machining Center as a lathe.

(h) Clamp a suitable size angle plate to the table and clamp a contouring lathe tool to the angle plate. This will be much harder that setting up the tool in a lathe, and you will to be very careful to get the correct rake/lead/etc.

(i) Pick up the center of the blank on the spud in the spindle and the tool tip that you have clamped to the right angle plate. Calculate offsets as required.

(j) Load the cnc program you have written, being especially careful with tool offsets and diameter compensation. A very common problem is verifying correct direction of spindle rotation. Note that you want the rotation/cutting action like a lathe to avoid backing the blank off the arbor/spud. Most likely with producing only a few parts, it will be easier to manually move the table [over or shift table zero in the program] and repeatedly run it that it will be to program multiple tool passes to complete the part in a single program.

(k) Use a strap wrench or other non-marring method to remove the completed part, and install the next blank. Be sure to return the table to the correct starting point or reset program zero shift.

Note that with a full sized marching center you can adapt the gang turn principal used on some cnc lathes, and effectively "change" tools, for example you can also mount a grooving/cutoff tool or knurling tool. It all depends how elaborate you want to get in the fixturing/tooling. After this exercise, I think you will understand why both cnc lathe and mill/maching centers exist.

First thing to do is create a cad drawing of your desired chess piece(s).

Good luck on your project and let us know how you make out.

Unka George (George McDuffee)

There is something to be said for government by a great aristocracy which has furnished leaders to the nation in peace and war for generations; even a democrat like myself must admit this. But there is absolutely nothing to be said for government by a plutocracy, for government by men very powerful in certain lines and gifted with the "money touch," but with ideals which in their essence are merely those of so many glorified pawnbrokers.

Theodore Roosevelt (1858-1919), U.S. Republican (later Progressive) politician, president. Letter, 15 Nov. 1913.

D Murphy wrote in news:Xns97B475755609BW12BU20MU38SY@130.133.1.4:

From my experience, it would probably be cheaper, or as cheap anyway, to buy a new machine than the mainboard.

Basically a 'brain transplant'...at least w/ many a the older units.

"PrecisionMechanicaL" wrote in news:e36j7a $n97$ snipped-for-privacy@emma.aioe.org:

Yes, and the last one we had to do was $27,000+, just for the parts.

replying to PrecisionMechanical, Chad wrote: nerd

replying to PrecisionMechanical, Chad wrote: nerd