Messages

321

Show"N"Tell ( Your Machines) / Re: Chads new machine

« on: May 11, 2006, 11:10:28 PM »

Thanks art, it has been a real challenge.

Just thought i would post a pic.  The first spirals !! 24"

from left to right they are 300 ipm, 250, 200.

The left one has some wiggles at 300. Not surprising considering i haven't trammed anything yet, the table supports haven't been leveled, the servo motor tuning would  be described best as just barley working, and my precision pen holder consisting of a foot and a half piece of aluminum C-clamped to the z with -the electrical tape precision pen holder attachment

The z is a 8x8 steel tube and it makes a great megaphone with the pen doing it's best impression of fingernails on a chalk board.
It was almost UN barrable, but i was having fun watching it draw the circles while standing on the side support. The machine didn't even know i was there! HHm that gives me an idea! i should weld a chair to the side so i can ride along while it cuts. Or maybe not.


Chad

322

General Mach Discussion / Re: Laser tool path displayer( IDEA )

« on: May 11, 2006, 04:18:22 AM »

Benny,
I used to design and build Professional Laser display hardware. I can give you a little info on this stuff.

First, it is a great idea. I thought it would be nice too.

The problem in the laser world is nothing is cheap. Pro optical galvanometers (scanners) are ~$1500 a set without power supply, a nice 635nm 10mw (red) laser diode is ~$50, now you have to have something that can drive the galvos ~$2000 and up.

Scanners use a balanced +-10v pp analog input,no step and direction here.
The other problem is your scan rate has to be high enough for the persistence of vision trick to work. If not you just see a dot running around. you also have to have galvos that have a high scan angle ( or a really tall ceiling)
 There is some cheap Chinese patent infringing knock-off stuff that probably be kluged together but that is still in the ~$600 range and you still have to figure out how to get g code to scanner.
Another issue, mach 3 is not fast enough. You could probably tweak a grex and use the analog output, that would get you closer to the 20,000 to 80,000 points per second the good stuff runs at.  i think the g rex analog out is only 8 bit though. In other words you would only have a resolution of +128 -128 for a total of 256 x  by 256 y. But the good news is you could modulate the laser intensity to simulate depth.

Scanners don't ever make a full revolution. They are limited to (for good ones) 80 degree optical.
Stepper motors won't work because of... well it is a stepper. You see the detentes. You could go to a very fine micro step and maybe get sort-of acceptable resolution out of them but then you have the speed problem again. With a gazillion micro-steps you have to send the data that much faster to keep the scan rate up high enough for persistence of vision to work.   

OK, assuming we got all of that worked out we have the, geometric correction, linearity ,focal point size, diversion thing to work out.

What you are seeking is the holy grail for laser nerds like my self. I have spent the last 20 years trying to come up with a $10 dollar high quality scanner set. The systems i used to build were in the ~$250,000 range, unfortunately to do this stuff well ain't cheap ;(

Now on to Chan's stuff. He has spent years perfecting his creation. And i must admit that he has done a bang up job. He is using some very tweaky electronics with an even tweaker feed back system, and getting great results!
There is another guy named Norm and he is building some home brew stuff, inspired by Chan.

http://24.200.192.31:81/LaserShow/LaserShow.htm

He is using a much better (simpler)  feedback system. He is also doing great stuff! I have my own version on the back burner but the mill is eating all of my time.

A cheap video projector taped to the roof would work just as well and be a lot cheaper!

Any way it is fun to think about, let me know if you come up with anything ,we will make millions.

Chad
 

323

Show"N"Tell ( Your Machines) / Re: 1st 'Beta' release of the MachBlue Screenset

« on: May 09, 2006, 03:48:34 AM »

HI guys, sorry for the delay. Been very busy both personally and working on the project.

The mill is going to be a 5 axis mill for cutting medium density fiberboard (mdf), foam, and tooling board. The plan is to carve positive bucks to make molds for fiber glass and carbon fiber race car parts, mostly air foil elements, under-trays, wings, body's.  My partner owns a couple of Formula -s cars and we are planning on producing updated body parts for these cars.

The mill is 10' x 12' x 48" inches X,Y,Z respectivally. Currently it is using rutex drives for the x,y,z,b,c and it probably won't be too long until we upgrade to ~1k range ac servo. All of the drive reduction are from verry nice alpha gear planetary gear reducers. We are currently going to be using a 3.5 hp router, will also probably be upgraded to an actual spindle down the road.

So far i have the X,Y,Z running and things are looking good. The X&Y are capable of 600 ipm rapids and the z is good to 250 ipm. All of the linear slides are IKO or Thompson. X and Y are 45mm rails and the z is 25mm. Z is ball screw driven and the x and y are belt(45mm). Without the wood table it weighs 2900lbs. the moving Gantry with y,z,c,b will be around 1300lbs.

I have built lots of stuff in the past but nothing so big and heavy, Turing out to be a lot of work --- and fun

Here are a couple of other pics for you to look at, if you have any other questions give me a hollar.

chad

324

Works in progress / Re: The start of Mach Blue Lathe for those that requested a Lathe Set

« on: May 07, 2006, 01:09:30 AM »

Whell now i have another default.  Thanks guys!! you do great work.

chad

325

General Mach Discussion / Re: want some simple circuit to test mach3 with a small step motor?

« on: May 05, 2006, 12:54:35 AM »

HI, wheel if you have a solid electronics background then you have everything you need to get started. I just looked at the data sheet and you don't need much else.
http://www.onsemi.com/pub/Collateral/MC3479-D.PDF

motor
Driver IC
parallel port
power supply
1 resistor (for current set)
Mach3 and a bread board.
wire

If you don't have an electronics background then i would recommend purchasing a small pre built stepper driver board, hooking that to the parallel port and get acquainted with things that way. I always end up spending more time building things that i should have just bought




Chad

 

326

Show"N"Tell ( Your Machines) / Chads new machine

« on: May 05, 2006, 12:34:52 AM »

AAAH The lighter font color is much better!! thanks! Now if you guys could do a X,Y,Z,B,C verson for my little project all would be right in the universe

Benny: I know i could change it in screen 4 but what can i say, i am lazy

Here is a pic of it on my mach machine ( in progress) with MachBlueLight

chad

327

Works in progress / Re: 1st 'Beta' release of the MachBlue Screenset

« on: May 04, 2006, 05:26:21 PM »

Hi guys , first of all GREAT screens!!!  I can't say that enough!!  THANKS mach blue s now my default screen.

I have done graphic design and i know what a pain it can be.

If i were to beg for one change it would be a different color for the dro's, the black on blue looks great but it is a little hard to read at a glance.
Yellow,white,light blue,Green something that sticks out a little more.

Now all you have to do is get together with Brian and the other wizard people and homogenize the gui for everything "grin"

chad

328

General Mach Discussion / Re: What's the best way to determine motor velocity?

« on: May 04, 2006, 05:14:24 PM »

sshneider, #1 is not true.

My understanding is (Brian correct me if i am wrong) fro will go beyond the motor tuning max. The motor tuning will dictate what a GO speed is. I think the conventional wisdom dictates that the fro is used primarily to slow down a job, or speed up a little bit. I think the way the pros use it is to fine tune a running program and not as the global speed knob. In other words set your F rate at the speed at, or faster than you want to cut and use the fro to adjust down.
If you are at 290% then you should have set your F much higher, this way you are still within the tuning.

I would tune to the skip point then back off 15% for safety and crank up your F to match, or back off another 20% and you can go higher on the FRO.

?!? 

chad

329

General Mach Discussion / Re: O.T. Need some advice on tapping LOTS of 1/2 holes.

« on: March 13, 2006, 02:09:08 PM »

Thanks Brian. Tapping heads, that is what I was looking for. Have my msc big book out and boy are those things Pricey! Did a re count and came up with 276 tapped holes ranging from #10 to 1/2.
I will be able to enter the "worlds strongest wrist contest" after I am done.
I purchased good hss spiral taps for everything so I think those will work. I guess I am going to have to bite the bullet and purchase one. 

Thanks for the link, now that I know what I am looking for I will do some digging and find something that will work.

Thanks,

CHad

330

General Mach Discussion / O.T. Need some advice on tapping LOTS of 1/2 holes.

« on: March 13, 2006, 12:22:00 PM »

I am starting on my Gantry router and the steel should be here tomorrow. I have lots (~140) of 12mm and half inch holes that need to be tapped for the rails and am looking for suggestions.  How do the "auto tappers" work. Do they reverse when you pull up? do they auto reverse by themselves? do they mount via a r8 for example or do they have a shaft that can be put in a Jacobs chuck and used in a plain old drill press?  who makes them? Sorry for all the questions, I hand tapped a couple of half inch in 1/4 inch steel yesterday and came to the conclusion that it is going to suck to do all the tap holes by hand.

Thanks,

Chad