neat machining videos

Start of ongoing list.

CNC porn:

• Hard core mass production CNC: http://www.youtube.com/watch?v=MwgobIVj4fU
• Another fun one by the same people: http://www.youtube.com/watch?v=lcGHtI9Lql4&NR=1
• And another for a mill: http://www.youtube.com/watch?v=3SUQKGu7F5w&feature=channel
• Fast CNC cutting: http://www.youtube.com/watch?v=sYqN90gHOZM
• Now this is a production setup: http://www.youtube.com/watch?v=-J4RlAmBuEo&feature=PlayList&p=199985F23F191210&index=1
• nakamura CNC lathe: http://www.youtube.com/watch?v=a3Gtr4WbtNw

Machining tricks:

• Indicating workpiece in seconds: http://www.youtube.com/watch?v=tn7A9PqNftY
• Steady rest facing: http://www.youtube.com/watch?v=ThVprkb2w6g
• Using CNC mill as lathe: http://www.youtube.com/watch?v=Ezx_hCSJDLQ&feature=PlayList&p=C228FBAE81E4F35A&playnext=1&playnext_from=PL&index=4

Building CNC links:

• Neat home brew CNC lathe w/ a crazy tool changer: http://www.youtube.com/watch?v=Y1IDHIcyHLY&feature=related

• Cheap to build CNC dremel mill (from instructables). Not powerful or accurate, but seems like a good starter project before building something serious: http://www.youtube.com/watch?v=6drMZqmyXQc
• Same guy: building cheap CNC driver board: http://www.youtube.com/watch?v=ZUyqscxLJ4k&feature=related

For those poor suckers living in CA: call Schwarzenegger *NOW*

AB962 is sitting on his desk. It will ban mail order ammunition, along with other problems. If he does not actively veto it by Oct 11 it becomes law.

What to do:

Step 1: call 916-445-2841 Step 2: Press 1 for English. Step 3: Press 2 for commenting on a bill on the Governor’s desk Step 4: Press 2 for AB962 Step 5: Press 2 for Oppose Step 6: Repeat as necessary (preferably once or twice a day).

http://www.calguns.net/calgunforum/showthread.php?t=223525&highlight=prompt+ammo+ban+phone

This is a malignantly spiteful bill that is useless for reducing crime. It will likely increase death/accident/injury given that it makes ammunition more expensive: the majority (in my opinion) of gun owners are already undertrained, and this will make it worse.

Stepper links

Since the main point of all this electronic stuff is to build some custom CNC machines, time to start a collection of links:

• Nice H-bridge tutorial: http://www.mcmanis.com/chuck/robotics/tutorial/h-bridge/bjt-circuit.html
  
• Some notes on doing motors on arduinos: http://www.ladyada.net/make/mshield/use.html
• Arduino on steppers: http://www.arduino.cc/en/Tutorial/StepperBipolar
• Good stepper tutorials: http://www.societyofrobots.com/member_tutorials/node/168 and http://www.societyofrobots.com/member_tutorials/node/120
• Reverse engineering which stepper wires to use: http://wwwhomes.doc.ic.ac.uk/~ih/doc/stepper/others/
• Even more stepper motors w/ lots of data:http://www.st.com/stonline/products/literature/an/1679.pdf
• Related: how to use an oscilloscope: http://www.doctronics.co.uk/scope.htm

Fixing arduino upload problem on linux

Symptom: the arduino IDE will upload your sketch no problem, but using avrdude raw only works the first time. Pulling the USB cable out and plugging back allows it to upload again (once).

Solution: (from http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1201441300): it seems to be a problem w/ the linux driver. Just insert "stty -F $(PORT) hupcl" right before the avrdude command (where PORT = the usb device such as "/dev/ttyUSB0"). E.g. in the Makefil:

stty -F $(PORT) hupcl
$(AVRDUDE) $(AVRDUDE_FLAGS) $(AVRDUDE_WRITE_FLASH)

You may also have to set your baud rate to 57600 (at least for the 328p).

It's such a relief to not have to use their IDE! Point+click to edit was driving me nuts.

Arduino. Or: How to hack electronics w/o knowing a damn thing

I've paused on the colt stuff to learn some electronics + micro-controllers (the little chips that get stuck in your car, fridge, cell phone, etc) so that I can build my own computer controlled machines. The "Arduino" boards are a great way to go about it. You can download code onto them from your computer across the USB port and then use this code to control electronic things you wire together and plug into the board. (E.g., by reading whether pins have power or not, and setting power out on other pins.)

The "hello world" program is to hook up a LED light + a resister to the chip and make it blink by turning a pin off and on. I've only ever used computers to toss around 0s and 1s, so it's neat to make them control atoms (sort of). Hopefully by the end of the weekend I can use it to drive some stepper motors that I can then attach to a lathe to make it computer controlled.

Here's a set of great class notes aimed at artists from "todbot" (http://todbot.com/blog/spookyarduino/)

http://todbot.com/blog/wp-content/uploads/2006/10/arduino_spooky_projects_class1.pdf

http://todbot.com/blog/wp-content/uploads/2006/10/arduino_spooky_projects_class2.pdf

http://todbot.com/blog/wp-content/uploads/2006/10/arduino_spooky_projects_class3.pdf

http://todbot.com/blog/wp-content/uploads/2006/10/arduino_spooky_projects_class4.pdf

If microcontrollers and electronics has always been mysterious, I'd really recommend checking the notes out --- the audience is non-technical artists, so it requires minimal knowledge. On the other hand, it's not pablum. He shows how to build cool stuff quick.

If you are going to go this route, just buy the $89 kit at: http://oomlout.com/ards.html Everything included to go from nothing to cool things. A bunch of different projects, many variations. I've spent all friday night tweaking on it!

Useful links:

• A bunch of neat arduino links: http://www.tigoe.net/pcomp/code/
• Useful blog tutorial on how to use a voltmeter: http://www.ladyada.net/learn/multimeter/voltage.html
• And more generally an arduino tutorial at the same blog: http://www.ladyada.net/learn/arduino/index.html (Which turns out to be the person I bought my arduino chips from! She has a post on how to build a cell phone jammer: http://www.ladyada.net/make/wavebubble/)
• Soldering guide: http://www.epemag.wimborne.co.uk/solderfaq.htm
• The comments of this thread are very useful: http://todbot.com/blog/2006/12/06/arduino-serial-c-code-to-talk-to-arduino/
• Nice set of tutorials on arduino and many other related things: http://itp.nyu.edu/physcomp/Tutorials/Tutorials
• And, of course, the "official" arduino forums: http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl
• Heat sink discussion: http://www.thebox.myzen.co.uk/Tutorial/Power.html
• Awesome electronics lessons: http://mysite.du.edu/~etuttle/electron/elecindx.htm

sending gcode to a bandit controller on a wells index CNC milling machine

There's at most one other person on the planet that needs this information, but since I spent hours (and hours (hours (...))) looking for it, here it is.

Currently I only know how to send using "hyperterminal" on windows. When it starts tell it to connect to the serial port (If you don't know what this is: you pull down the hyperterminal menu which will say something like com3, com4 or other --- just try these until it works).

You set:

• data bits: 7
• parity: even
• stop bits 1
• flow control: hardware
  

Then under "properties" set:

• windows keys
• autodetect
• send line ends
• wrap lines
  

To send a program to the bandit:

• put in ext mode
• press "CE" and then "start"
• In hyperterminal "send ascii file."
  

Here's a trivial program to move on the X axis one inch:

N001&0
X-1.0
M2

The "N001&0" seem required at the beginning. And "M2" states its at the end of the program.

After it loads

• put the bandit in run "continuous mode"
• hit reset (to put the machine to the beginning of the program)
• hit start.
  

It should move one inch. If it doesn't and the red error light keeps going on when you try to the program, sure you've pushed the "axis enable" button.

I am using a laptop. Since modern laptops no longer ship with serial ports (at least mine doesn't) I'm using a USB-to-Serial converter from Frys. The first one I bought was broken, which really jacked up the whole process.

If anyone can figure out how to send using linux that would be great! I've tried cu, minicom, and a random com.c program from the net. Something doesn't seem right. The bandit red light of death goes on (so it received something) but it's definitely not the right thing.

Useful post on converting an emco compact 5 to modern hardware

I've been spending a lot of time trying to figure out how to build my own CNC.

This is a nice rundown on how to convert an emco compact 5 lathe by Art Fenerty (he wrote Mach 3):

Just to kick in on costing of such a project ( having converted my emco PC5 last year. This isnt a plug for my software, I retired over a year ago from Artsoft, just info for those interested in such a conversion. )

My costs were..

Motor drivers, about 100.00 each ( 2 required. ), I used some I had from ebay that I got for about 50.00 each, prices vary, but I used 10uStep controllers @ 3amps, 24 volt. Gecko's work great, as will almost any microstep driver.)

Motors ( you can use the ones currently on a pc5, but they are very weak, or mine were anyway. You couldnt even feel the torque detents as you rotated them without power. 500oz inch ( approx) cost me about 50.00 each , but you dont really need that power. ( though its nice to have ). My power more than tripled on the axis, they cannot be stopped by hand at this point, and they are much faster.

Power supply ( the one in the emco can be used, no need for an additional one. You can tap the original power supply for 24 volts for motor drives, and the 110volts for the breakout board power. )

I also added a breakout board for interfacing. The breakout board from pmdx.com fits well in the spot where the original
emco pc com board fits in the machine. Cost approx $129.00 US. The mach3 web based form has photos of the conversion I did,
everythign fits well int he Emco casing and made my pc5 a much more usefull machine.

I also added a sensor for threading, and put a bolt in one of the original slots to trigger the sensor for speed and threading. Mouser electronics 653-ee-sb5v is the sensor I used. About $20.00 for that.

Of course I didnt have to pay for the software. :-)

The emco works very well now, has no file length limitations, and lazyturn generates code that runs pretty well if you have nothing else available. ( free from the mach3 web forum till I end up adding a final finish pass. ). The only possible dodgy part is the
threading. While threading short threads works well, after a couple inches of thread there is a bit of wander that makes the thread imperfect, though nuts do spin on with no binding. This is the result of single pulse per rev threading. Still being worked on slowly, but seems to work well for most threaders, depends on the pc and sensor configuration and setting as to how well it works.

So my total cost was about 350.00US or so ( somewhere about 175 EU ) , adding software would make it about 300EU for a complete conversion.

The same conversion would allow EMC or other software to run the lathe. If one used an encoder for the spindle EMC woudl do perfect threading on it, or if one can figure out the original sensor in the pc5 to feed the software. ( I never could get mine working but it may have been defective from the start, I never used it prior to converting, so I just tore it out and replaced it with my 20.00 sensor..)

Alternately, instead of a breakout baord a smoothstepper device, USB based could be used, the smoothstepper is also known for perfect threads. All I can tell you for sure is the upgrade makes the lathe run much better than stock, much more powerfull, faster, and more reliable. Much depends on what you use it for of course.

Thanks,
Art

And his continuation of the same post:

>>I searched around: is this the thread you mean on your conversion?
http://www.machsupport.com/forum/index.php/topic,214.0.html


Yup, thats the thread.

Wiring isnt as bad as it looks. Where you see I added a pmdx breakout board, is where the emco put their pc interface card. You just rip that out entirely. ( if you have the same machine I do.. ). Your new motor drivers wire directly to the pmdx board, so between the docs for the drivers and the docs for the pmdx, all the wiring is described. Now I added 2 drivers and a pmdx, and 2 motors, the motors wire directly to the drivers ( real easy to wire the motors.. ) , and the pmdx board simply gets a printer port cable which I wired to the pc printer port plug on the back of my emco.. and then it wires to the drivers.. ( step/direction and com ) so 3 wires to each driver from the breakout board. I put 2 7 amp drivers and a PMDX in the same area.. they all went in just fine and with little effort. Chinese drivers or geckos all run about 120.00 I think for pretty high current drivers.

As to the power supply, yell if you like when you get there, its easy to find the 24volt spot on the emco supply. Lots of current available so no extra supply is necessary at least on the PC5 version of the Emco, those two points on the emco ( 24vdc and common) wire to each of the drivers to supply power to them, the pmdx just gets a tap to the 120vac line inside. Again, pretty easy.

Thats it, no other wires really need to be done unless you want threading.. the sensor can be a bit of a bitch to wire if you dont do electronics, but again, yell when you get there, its only 3 wires to the sensor from the breakout board.. and then I put a screw in one of the slots of the slotted wheel, the sensor see's it on every spin. The sensor bolts in the same bolt holes the old emco sensor did as I recall. I can take better pics if you get to that stage. But you can cut fine without the threading sensor. ( I dont cut threads usually..). If your firend can get that sensor that comes with the Emco running, then even better as I do have a special plugin that will use an index slot and multislot timing pulses for threading. Tests show it works well, but there is a wandering after an inch or two. Still holds nuts fine, but with Mach3 dont expect Boeing quality threads unless you use a smoothstepper.. its simply a limitation
of running from Windows. On the bright side, for those that need perfect threads, this described upgrade isnt just to make the emco Mach3 compatible, its also EMC compatable at that point, so if you like linux, you can run EMC as well. ) or pretty much any other step/direction controller. Steve Stallings, the pmdx inventor is an EMC group member and pretty knowledgeable about such things, Im sure many could help you get that up and running.

By the way, the new motors simply bolted in the same spots the old ones did, no work required at all.. you just wire the 4 wires from the motors to the drivers.. pretty easy.. Any basic electronics person will find it painless to do such a job.. ( and many people who know only about basic dc wiring..). Ill post Mach3 settings for the emco if anyone wants them.. it configures pretty easy and runs real well. No limit on file size at all.

Just my opinion, but if one is to upgrade an emco, Id really recommend going this route simply because it makes it compatable
with pretty much any controller that will send step/direction commands. The future will probably bring about things like SCurve controllers, ( which smooth out motion quite nicely), or other advances in technology which , if you go proprietary you wont be able to take advantage of. We all know how long these lathes last.. pretty much forever, so having a standard type of control has its advantages. ( Emco's also seem to sell for more if they are step/dir controlled thus allowing a new owner to pick their favorite software. ). Price wise, it seems if anything quite a bit cheaper to go this route, and then its done and standard, but thats just my opinion.

I usually dont kick in on such discussions as some may feel Im pushing for Mach3 to be used, and since I wrote it Im obviously biased,but I am retired.. I only work on things like future control code these days. So that having been said, you should probably ask as many groups as you can what your best plan would be. Ive never used WelTurn , the specs dont appear to be shown real well so I cant tell you max speed vs EMC or Mach3. At about 900.00US it seems pricey to me,specially if you have to then add new motors, complete conversion to step/direction is about 300.00 to 400.00US if you stick with your emco motors, I just found my emco motors so slow they drove me nuts. Max speed on my machine is set for 554 mm/minute, I could go quite a bit faster, but at 554 I never lose steps unless I jam into material. ( In fact the carriage would snap my hand off if I tried to stop it..), acceleration is set to 91mm/sec^2 and standard setting is 2000steps/mm. ( because I have it set to a high uStep setting, which is nice if your drivers support that. ). I tend to limit my speeds because using max speed rates on something like an Emco does stress it too much, but 550mm/sec seems very doable, and my lathe has no trouble with it at all.

At 2000steps/mm, Mach3's lowest kernal speed of 25Khz can do 720mm/min max, higher kernal speeds could double that quite easily if your motors can handle it, but I dont suspect an Emco can handle a meter a minute. My motors were advertised on Ebay for 750oz in, (Deep Groove) but I dont really believe it, I thing they are 500oz in or less, but I have to admit they are very powerfull, orders of magnitude above the steppers that came with my emco, the difference is not only audible, but amazing and very powerfull, the original motors I could easily stop with one hand, I would'nt recommend anyone trying to stop these puppies with their hands..not if they like having hands. :-)

My only problem is that my lathe has the AC motor driven spindle , which makes it quite low torque, my buddies emco ( You can see Brians on the group forum somewhere as well ) has the DC motor spindle, and Ive seen him do 1/4" of steel in one pass ,
(in fact theres a video somewhere showing it do that at a pretty high feedrate. Perhaps emco's with dc spindle can all do that, I only know the few Ive worked on). To me thats a pretty high rate of speed for 1/4" in one pass. No possible way my spindle could do that, I limit to 1mm per pass or less usually, but since feedrate is quite fast it doesnt seem an issue to me. I cant see any posting of welturn max speeds or step rates on their site, perhaps someone can post their experience in terms of speed and at which point they start to lose steps. Any comparison would be interesting to those considering updating hardware or software.

The welturn software does seem very nice to use from what I can see though, and any software is an upgrade from the original dos version of emco IMO , it seems pretty limiting and pretty non-standard in its Gcodes. CNC is all about standards what with the CAM packages available. Each person has their own requirments though, so check out every option as thoroughly as you can before you make a decision.

Again, this is all just my opinion, I know of many emco's that run Mach3, and several that run EMC, all seem pretty happy. Its not
a conversion project that should scare anyone with $400.00 or so to burn.. took about 3 hours to do mine, of course it may take
longer if your not used to cnc wiring, but its not brain science and very little wiring really needs to be done. Threading seems the only real issue, there are several ways to do it, and performance there will vary with software, methodology, sensor and experience.

While I think of it, the other issue you may want to think about is an auto tool turret if you have one, ( I dont ), Mach, and EMC can be configured for it, the pmdx interface board has lots of spare outputs when used with a lathe, and macro's can be written to
run it, but I havent done any for myself. From what Ive heard when I did support they just used a timed macro to run the motor, wait for a switch to hit, then run backwards for a couple seconds to jam it into position. You can also do things like add lights, blinking indicators that job is complete, relays for various optional functions.. all advanced topics if you do go that route... the various support groups are pretty good with information on such things.

Hope these thoughts help, sorry for the verbosity.

Thanks,
Art

a useful healthcare comment

Usually blog comments are worthless (or worse). This one is a welcome counter point to the typical nattering:

Thorley Winston:

My preference for health care financing reform (since no one is really not talking about health care reform) starts with:

a) Give consumers who buy health insurance the same tax breaks as employers who buy health insurance for their employees (no fines or mandates) or make all health care costs fully tax-deductible. I’m not a fan of employer-based health insurance but most people are satisfied with but I think we can at least give those in the personal health insurance market the same tax treatment.

b) Allow consumers and employers to buy health insurance policies across State lines like we can for life insurance, auto insurance, and every other legal good and service (if you want competition, that’s the way to do it).

c) Remove barriers to allow small businesses and other organizations to form Association Health Plans (about 60% of uninsured Americans work for small businesses).

d) Encourage high-deductible policies that cover catastrophic illnesses and Health Savings Accounts. These policies tend to have lower premiums (which make them more affordable especially for younger and lower income people) and we can start to develop a more robust market (along with price signals) for routine care costs instead of having them covered by third-party payers.

e) Automatically enroll those who are eligible for Medicaid in Medicaid (about 25% of uninsured Americans are those who are eligible for Medicaid but don’t enroll until they need to see a doctor).

f) For the poor who don’t qualify for existing programs and/or for people with preexisting conditions for whom it is still cost-prohibitive to buy health insurance, let the States experiment with targeted subsidies or creating insurance pools for these individuals.

g) Give doctors who provide unreimbursed care a tax deduction or tax credit for charity care.

I haven’t addressed several issues like medical malpractice reform and Medicare reform (both of which I think we desperately need in our country) because I think they’re volatile enough that they need to be addressed separately. I also think we need to (on the health care side of things) look FDA reform for drug and device approval, increasing the number of doctors in the country and/or the ability of other trained medical personnel like nurses and physicians assistances to provide services, health IT reform, wellness clinics, etc. All of these are important and distinct enough that I think they can and should be addressed separately instead of being thrown into a thousand plus page bill that sinks under its own weight.

Full text at: http://meganmcardle.theatlantic.com/archives/2009/09/political_theory.php#comments

Before killing doctors, let's do lawyers first.

Funny op ed in WSJ on doctors regulating lawyers. That would be, literally, "change you can believe in":

http://online.wsj.com/article/SB10001424052970204731804574387021307651050.html

Hat tip: volokh.