The Collected Wisdom
of the Haas Answer Man

Miscellaneous Topics
(they don’t seem to fit anywhere else)

(early 2005
vol 9 # 32)

Dear Applications:

I’m loading programs into my SL-20 through the RS-232 port, using Microsoft XP-Pro’s HyperTerminal. The data is reaching the control just fine; however, most of the program lines are encased in parentheses, with a question mark at the end of the line. I’m getting:

(N10 G01 X5.4375 Z3.50 ?)
when what I need, obviously, is:
N10 G01 X5.4375 Z3.50

I’m also getting Alarm 243: “Bad Number. Data entered is not a number.”
Do you know what’s going  on here?

Steve Yang
 

Dear Steve:

Check Setting 9 on your SL-20 – it’s probably set to MM (millimeters), which is the most common cause of this problem. When Setting 9 is set to INCH, the control reads programmed units to four decimal places; when it’s set to MM, it only reads to three decimal places. If it’s set to MM, and programmed values have four decimal places, the control flags those program lines as unreadable.

Sincerely,
Haas Applications

(Spring ’04
vol 8 # 29)

Dear Applications:

We have four Haas machines, including an SL-30 lathe. We’ve been running parts on some older, smaller lathes that require both turning and boring. We’d like to move these to the SL-30. Can we use our existing programs “as is” on the SL-30? Also, what type of tool bushings do you recommend for bar holders on a bolt-on turret? Any other hints are welcome, too.

     Len Flockstra

Dear Len:

Yes, you can use your existing programs, as long as your older, smaller lathes have G-code controls. As for the bushings, we recommend split bushings for holding boring bars, as these tend to reduce vibration and cutting tool harmonics. Make sure you don’t over-tighten the toolholding bolts – this can affect the position of the tool in relation  to the part, causing the tool’s cutting edge to be off the centerline. Here are a few other guidelines to keep in mind.

     Please don’t hesitate to call us for further assistance.

     Sincerely,
     Haas Applications

(Fall ’03
vol 7 # 27)

Dear Applications:

Do you know of any PC-based G-code interpreters that closely match (or identically match) the Haas interpreter on the Mini Mills? We have many students learning to use the Haas machines. When they generate G-code (using Virtual Gibbs), the Mini Mill inevitably discovers errors with the code during screen pass. Rather than waste valuable machine time, it would be better to have students run a screen pass on the PC and make necessary changes. Does Haas offer such a utility? Do any exist elsewhere?

     Adam Bowen
 

Dear Adam:

You have a couple of options. Haas offers low-cost CNC control simulators, which are popular items at a lot of schools that use Haas machines. In addition to proving out programs, simulators let students get familiar with the Haas control without taking up valuable machine time.

     You can also use MetaCut Utilities, a very handy program for verifying toolpaths. On the Haas website, www.HaasCNC.com, go to the solutions/applications menu, click on Industry Links and look under CAD/CAM Utilities. MCU offers a free 30-day trial.

     Sincerely,
     Haas Applications

(Summer ’99
vol 3 # 10)

Dear Applications, 

I’m having a problem with chatter while finish boring a deep 2" diameter bore on my new CNC mill. It would seem to me that this job is not too much to ask of a CNC as I have done this type of operation in the past without incident on my manual mills, just not as deep. The bore extends 10" into the work piece. The material is cast iron. The steel boring bar that I’m using is micro-adjustable and the insert has a small nose radius. I’ve used a bar extension just long enough to allow the insert to reach the bottom of the bore without interference from the spindle. Shouldn’t a new CNC machine be able to bore deeper than a 20-year-old manual? I’m looking for a solution and your recommendations would be appreciated.

     Sincerely,
     Mike Owens 
 

Dear Mike,

Machinists familiar with manual machines often feel that a new CNC should offer more performance than a manual machine. In many ways they do; however, a modern machine tool is not a manual machine with a control added.

    CNC machine tools rely on different operating parameters than manual machines. This difference is necessary to maximize performance of the servo system. For example, no manual machine can tolerate 710 in/min rapids, and they are not asked to follow 3D surfaces. While CNC machines do not amount to a compromise, it is not always correct to duplicate setups from manual machines on a CNC. With a CNC machine tool, performance is always linked to tooling performance. Tooling has advanced in step with modern CNC machine tools, and we highly recommend that advanced tooling be used in challenging applications such as deep-hole boring.

     A steel boring bar should not be extended greater than 4 times its diameter on any machine. You may be able to nurse such a tool on a manual machine, but not likely with a CNC. Luckily, along with high-technology machines comes high-technology tooling – designed to out-perform its ancestors. Carbide bars can be used to bore holes up to 5 times the diameter in depth, and heavy metal (tungsten) or De-vibe brand bars can bore up to 10 times their diameter, which in your case will be more than enough and should fix your chatter problem. 

     Sincerely, 
     Haas Applications