This one kicked my backside and it took me awhile to figure out the answer. I was using CAT40 Lyndex ER-16 collet holders and had two units that would not run concentric. I cleaned the collets, used different collets, cleaned the collet recess in the holder, tried everything I could think of. The collets would not hold a tool concentrically no matter what I tried. After examining the end of the collet holder under magnification (10x) I noticed that there was a slight ring embossed on the end of the stop screw in the center of the collet holder. It matched the end of the collet perfectly. The stop screw was preventing the collet from fully seating in the holder and the collet nut was only closing the FRONT END of the collet - producing a line contact with the tool shank rather than a surface contact along the tool shank length. After pulling out the screw (left-hand threaded), the collets ran true!!!!! I realize that this is way off topic, but I almost fed these holder back to my dealer the hard way - and it was my fault in the end.... Just thought I would pass along the lesson learned.

Thread forming is my choice for 6061 aluminum and 360 brass. I have done several thousands of 0-80 blind holes with a VegaRoll tap made by VegaTaps (making a couple of miniature antenna models for a customer). I did find out that cast aluminum plate (tooling plate) will grab the roll tap and break it - had to go to a spiral flute cut tap in aluminum tooling plate. The other thing I found with the small taps is to start the thread above the material about 0.100 - almost no breakage when I did that.

quote: 'Rekd teh Computers make very fast, very accurate mistakes. Don't forget "repeatable".......

+1 here also. I have found much help here!!!! Happy 4th!

Absolutely correct - the calculations let you know about where your machine limits are for speed, feed, and DOC combinations. With my Fadal 3016L I can run an MAFORD 1/2 inch cutter ot 6112 rpm with a DOC of 0.200 inches - full width cut. If I change to 0.250 DOC, my spindle loads down to about 5200 RPM in a full width cut (and about 100% load). Running the calculations tells me that I could run at about 0.230 DOC at my HP rating (actually at about 75%load - I can take a 0.220 DOC without slowing the spindle). That said, I don't run it that hard because it is a light machine and I don't use it in "disposable mode" - I own it and can't afford to burn it up.

There is a formula in "Handbook For The Metalworking Industries", 1st edition - starts on page 899 and ends on page 901. HP = Q x K where Q = [DOC(mm) x WOC(mm) x feed rate(mm/min)]/1000 (answer in cm3/min) Q is the MRR - metal removal rate DOC is Depth Of Cut WOC is Width Of Cut K is a factor from a table on page 901 - dependant on material and hardness. K represents the cubic centimeters of material per minute that can be removed by one horsepower. No formula was provided for K, just the table. Manipulating the formula gives you: DOC = [HP x 1000]/[K x WOC x feed rate] K varies from 0.0045 for 40 BHN magnesium alloy to .1146 for 600 BHN Stainless Steel. Mostly I just start with 50% of the cutter diameter and correct from there...... [ 07-03-2003, 10:00 AM: Message edited by: MetalMarvels ]

Happy 4th!! Wish we could have ANY sort of fireworks here - all illegal.... Have a safe holiday, everyone!!!!

The SP1 updates work for reading MDT 2004 files - my particular problem in reading the files is now history! I now have a happy customer who doesn't have to translate stuff before I can use it! [ 07-02-2003, 02:32 PM: Message edited by: MetalMarvels ]

We looked at Inventor and due to pricing and the availability of 3rd party tools that can be incorporated into Solidworks (not to mention the ease of importing into MC), Honeywell has chosen to migrate towards Solidworks. The "extras" and "maintenance" fees that ProE charges have also been an issue.

At Honeywell, we are now migrating towards SolidWorks. Mostly due to the price and pain of using ProE - as soon as we get someone halfway trained in ProE - the find a much better paying job........

Made a ton of RF enclosures and lids, a half-dozen cylinder heads for a WWI vintage Bentley BR2 Rotary Airplane engine, 200 headlight adjusters for a german-made car, and a run to the scrap recyclers to dump chips.......

Thanks, I will see if I can get them to provide the files in those formats.

I have a customer who recently changed to Mechanical Desktop 2004.... Now I can't extract the part geometry into Mastercam 9.1! Don't you just HATE that - it has been really nice to extract the geometry straight from their previous version directly into MC. They have also been having problems saving their MDT 2004 files into a previous version - they can't read it after they "down-save" the file (and neither can I). They also don't like to pull out IGES files because it is too easy to lose track of revisions. Does anyone know if a "patch" may be in the works for the embedded Autodesk file conversions utility in MC?? [ 06-26-2003, 12:19 PM: Message edited by: MetalMarvels ]

quote: Me four! Of course, I was one of the ones who didn't get it on the first go-around a few years ago........ [ 06-26-2003, 12:04 PM: Message edited by: MetalMarvels ]

With regards to results so far: The "G91 G28 Z0" line appears to do the trick, but I haven't tested extensively yet. Haven't tried the others yet - too busy cranking out parts.

Don't know about others, but I put "TA,1" in the "psof" section as follows: psof #Start of file for non-zero tool number pcuttype toolchng = one if ntools = one, [ #skip single tool outputs, stagetool must be on stagetool = m_one !next_tool ] #add communications prep code "TA,1", e "%", e n, *progno, "(", sprogname, ")", e "(DATE=DD-MM-YY - ", date, " TIME=HH:MM - ", time, ")", e pbld, n, *smetric, e pbld, n, *sgcode, *sgplane, "G40", "G49", "G70", "G80", *sgabsinc, "H0", "E0", "Z0",e

Me four!

Sorry guys, I got busy making box lids and haven't had the time yet to experiment. Will let you know the results as soon as I can!

quote: Formate 2 and you want incramentl, ok then. LOL More a case of the Fadal came set up in Format 2, I got a post that mostly worked in Format2, I didn't know any better, and I have been muddling my way through without a complete understanding of everything that goes on interactively in the control. I should probably switch to "native" Fadal Format 1 and change the post accordingly. I have started to notice neat little Fadal things that I can't use in Format 2. [ 06-23-2003, 05:48 PM: Message edited by: MetalMarvels ]

Jay, the I,J,K in the drill cycle line threw me for a moment. I am used to using the Q word instead. It does look like the I,J,K method has more flexibility. quote: N108 G98 G83 X.3708 Y3.7747 Z-.5 R.25 I.1 J.1 K.1 P.05 F5.76

Jay, I forgot to mention that I am programming in Format 2..... [ 06-23-2003, 05:33 PM: Message edited by: MetalMarvels ]

Thanks for all your replies! I think I might have found the problem - the "G91" - I will play with it tonight with no tools in the machine (or parts) and see what I can figure out. N100 G80 N110 M5 M9 N120 G0 G91 H0 Z0. N130 M1 N140 ( 7/32 DRILL TOOL - 13 DIA. OFF. - 13 LEN. - 13 DIA. - .21875 ) N150 T13 M6 According to the Fadal manual, a "G90 G0 H0 Z0" is functionally equivalent to a "G90 G0 G49 Z0" - similar in operation to the code in Jay's example. In my case I have Incremental Positioning (G91) rather than Absolute Positioning (G90) in use. In my case the "H0" acts like a tool length offset cancel - equivalent to the "G49" in Jay's example.

Mayday, I remember that we tried a G28 some time ago and got into some serious trouble (i.e. a new spindle ) and didn't go back to it. I suspect it is because we (ok - I) don't really understand what is happening at the controller with the various coordinate systems on the machine. CAMmando,that Z-hitch is exactly the problem.. Doesn't hurt anything unless my tool retract initial plane is too tall..... thad, I definitely have Z offsets in E1. I typically use a tool height probe for all of my tools (that way I can change out a tool in mid-stream) and set my fixture offset as the delta between my tool probe height and the part height. It is usually a positive Z offset in the fixture offset table. The Z-cold start position is at the tool-change Z-height, but I will double check tonight. If it is off - it is certainly not by more than a few tenths. In the example I showed, the tool height above the part is about 1.3 inches at Z-tool change height. The tool clearance is at 0.25 inches above the part with an incremental 0.01 retract height for all tools. The top of stock is set to an absolute value of 0.0 with an absolute depth of -0.03 for the spotdrill. I will experiment further, but perhaps there is some sort of interaction with a positive Z-offset in my fixture offset.......

This has been puzzling me for awhile now and I am now at a loss as to where to look for the “answer”. My problem is that after each tool completes, it retracts well above the tool changer Z-height then moves back down to the tool changer Z-height and completes the M6 tool change. I am using MC 9.1, a Fadal 3016L, and a modified MPFADAL post (modified to correct some rigid-tap issues and to add the “TA” at the top of the code). This only happens when one or more of the tool lengths are within 2 inches of the top of the part. It happens whether I use the G91 or a G90 (such as in line N120). If I use a large initial plane height (say 2 inches), the retract before the tool change can cause me to run out of Z-travel and cause a subsequent axis error. It is like the Fadal is “looking ahead” and goes to the M6 height and “adds” the tool retract to it. This happens if the previous op was a canned cycle or a regular cycle, but it only happens if a tool (at the tool change Z-height) is within a couple of inches of the top of the part. If the closest tool is farther than about 2 inches, the tools will retract normally to the tool change Z-height. Any thoughts??? TA,1 % N10 O0001 ( 110-50851A FRONT ) (DATE=DD-MM-YY - 23-06-03 TIME=HH:MM - 08:40 ) N20 G20 N30 G0 G17 G40 G49 G70 G80 G90 H0 E0 Z0 N40 ( 3 MM SPOTDRILL TOOL - 7 DIA. OFF. - 7 LEN. - 7 DIA. - .1181 ) N50 ( DRILL ) N60 T7 M6 N70 G0 G90 S6800 M3 E1 X6.94 Y-.313 N80 H7 Z.25 M8.1 N90 G81 G98 Z-.03 R0.01 F6.53 N100 G80 N110 M5 M9 N120 G0 G91 H0 Z0. N130 M1 N140 ( 7/32 DRILL TOOL - 13 DIA. OFF. - 13 LEN. - 13 DIA. - .21875 ) N150 T13 M6 N160 G0 G90 S4191 M3 E1 X6.94 Y-.313 N170 H13 Z.25 M8.1 N180 G83 G98 Z-.198 R0.01 Q.0656 F8.45 N190 G80 N200 M5 M9 N210 G0 G91 H0 Z0. N220 M1

A good book, with much to recommend it!