Messages

61

Show"N"Tell ( Your Machines) / Re: Supermax VCM-16VS retrofit

« on: January 04, 2007, 01:12:50 AM »

I got the chip tay made u as well. Used the plasma cutter to cut out the pieces I didnt want then mig welded them together. First time I got to use my new to me Powcon 300SM. Nice job. all I had was CO2 and no splatter even with that. Now just need to drill a few mounting holes to bolt it down and and paint it up.

62

Show"N"Tell ( Your Machines) / Re: Yet another Retrofit. Hardinge HXL-S

« on: January 02, 2007, 03:15:13 PM »

Mark, Nice set up!

FWIW your SB 9" is a model C. Model A has the Quickchange and power crossfeed.

63

Show"N"Tell ( Your Machines) / Re: Supermax VCM-16VS retrofit

« on: January 02, 2007, 01:06:47 PM »

Last week my motherboard in the little computer I was going to use died. I guess when the power supply blew it took out the motherboard as well. It seems the RAM and CPU are still good so I picked up a AsRock socket 478 motherboard new for $52. In cut a old desktop case in half front to back and installed the board and power supply. Reinstalled XP and everything seems to work good. I am going to scavenge parts out of the old SFF computer to hold the CD-ROM, hard drive, and smart card reader.

I am also looking into installing flood coolant. The base of the machine was originally designed to be used as a sump. I had some worries as the copper air line leading to the air assisted ball screw. I pulled off the cover off the base and stuck my digital camera in there and took a couple blind photos. I found that they has driller right through the wall of the sump. Ouch. And not only only one hole but three! I raised and locked the knee and removed the knee ballscrew. I yanked the old copper line cleaned out the holes with some spray degreaser. I then used some rubber well nuts and installed them in place with a bunch of silicone and tightened them up. I let them sit a while and then put a nice layer of silicone over that. I dont think coolant will get through that!

Since I had the ballscrew cylinder apart I took it apart since I had been hearing air leaking. I found the piston had came loose from the rod/screw and air was escaping through it. I totally cleaned the ballscrew and found aluminum chips in the nut so I pulled that apart as well. The nut is pretty worn. Looks like it will need replacing eventually. I cleaned it out and reloaded the balls and reassembled everything. I added a thin ship between the inner races of the angular contact bearing of the nut/pulley to increase the preload and to compensate for wear. I replaced the air fitting on the bottom to the pushlock type poly line connector and drilled holes to bring the air line out the side of the base along the side to the regulator in back. It moves smoother without all the chips in in the screw nut!

Got a little more done on the mill this weekend. The replacement scale for the one I crushed came in on friday. I picked up a similar model and was able to use my old long scale with the new reader head. The only difference was the new head output in ttl quadrature instead of the sinusoidal quadrature that the old head output in . Plus the new head was a fixed 10X mulitplication out. This gives me 50800 divisions per inch over the old 25400. A little overkill...

Not wanting to cut up cables I made a jumper that connects between the header connectors in the Heidenhain interpolator boxes. Works good. Though when I went o home the X axis would randomly stop thinking it hit the home switch. Eventually I figured out there was some crosstalk from the encoder on the X axis that was tripping the X home input. I moved the input to the other parallel port and the problem disappeared.

 I found out Mach cannot stop a spindle at a certain location. No big deal. So I just went with doing normal closed loop spindle control. Initially I tried using the keyence sensors to sense the edges of the fan blades but the pulse time was just too short. I then made a 4 sector encoder wheel in corel and glued it to the fan on the spindle motor. I still could not get a stable signal into mach. It would work fine up to about 1000 rpm and then loose the signal from the sensor. I initially though it was the Opto22 input module that I used to interface to the 5v logic could not handle the rise/fall times. I put a scope on the output of the Opto22 and found I was getting a good signal out. It turns out that again I was getting some crosstalk. This time from the step signal going to my VFD control. It was scrambling the signal going into the computer. I moved it to the other parallel port card and now I have a stable signal to the computer. I ran the spindle calibration routine sucessfully and enabled closed loop spindle control. Now if I put a load on the spindle it will compensate and maintain spindle speed. The next trick is to make a pickoff right off the quill. This way I dont have to do any calculations for ratios due to different selection in the varidrive.

My current plan to do this is to cut out a disc out of 1/4" aluminum and drill a hole radially through the edge and insert one of the fiber sensors. I will then make up a linear encoder strip which I will wrap around the quill for a 2 or 4 segment encoder. The disc with the sensor will mount to the quill cap. If this works I will make a more permanent encoder strip or may just paint it right on the quill.

Next project is to make up a drip/chip tray for the base for when I start to use flood coolant. I have a electrical panel cover from an old promass board loader that is almost perfect for that. I marked it out last night and will take the plasma cutter to it tonight and make it fit. I have a couple holes to plug up when some of the controls were also.

64

General Mach Discussion / Re: Wont home with scale attached

« on: December 30, 2006, 12:12:11 AM »

ahhh... forget it.

I moved the X home to another port and the problem went away. Must of been some cross talk in the interface board.

65

General Mach Discussion / Wont home with scale attached

« on: December 29, 2006, 11:58:22 PM »

OK, I finally replaced the head in my X axis linear scale that I smushed a few weeks ago. Its a 50800 line per inch reader head. A little overkill...

 The machine has been running good up until tonight. Heres whats going on...

I went to home all axis. Z goes, Y goes, X goes a random distance and just stops and zeros.. huh? Hit home again. Z OK, Y OK, X moves randomly and stops and zero. more huh?

Disconnect scale. X homes normally. Double huh?

Reconnect scale... X only moves randoms distance towards home. If I keep hitting x ref it will eventually get there an hit the home switch and comes off.

Any ideas? I am watching the input leds when it moves and stops and none come on.

66

General Mach Discussion / Re: Swapping axis'

« on: December 28, 2006, 12:14:19 PM »

Did what I said last night and clone the profile and modified the pin setting. I think this is going to work. I was just hoping there was a way to swap all of this in mach and not have to re-do my profile or edit gcode.

Thanks

67

General Mach Discussion / Re: Swapping axis'

« on: December 27, 2006, 04:44:29 PM »

Currently my plan is to clone the profie file and then swap all parameter between x and z, limits included. This will allow me to home and everything.

68

General Mach Discussion / Re: Swapping axis'

« on: December 27, 2006, 03:24:48 PM »

I think that is only for circular interpolation.

-Jerry

69

Show"N"Tell ( Your Machines) / Re: Supermax VCM-16VS retrofit

« on: December 27, 2006, 02:45:27 PM »

Also a couple pics of the harmonic gear reducer I plan on using for a fourth axis. It has a 101:1 gear ratio and absolutely no backlash. I figured out the pinout for the encoder and now just need to hook it to a counter and figure out its ppr.

70

Show"N"Tell ( Your Machines) / Re: Supermax VCM-16VS retrofit

« on: December 27, 2006, 02:40:01 PM »

Got my second set of bearings. Bridgeport sent out the second set next day air. I installed the bearings and also changed the x drive belt while I had it apart. What a difference! The control consold no longer shakes when I rapid!

Finally cut some steel with the mill. I got tired of my touchscreen moving away from me every time I go to push something so I cut a hole in the panel for it. I have been slowy designing my new control panel for the mill in solidworks. I exported it to a .dxf and popped it into lazycam and deleted everything except for the mounting holes and the hole for the LCD. I set up the panel in the mill, ran a couple air cuts to make sure everything is where they should be and then laid into it. Worked great, only I had the feedrate too high nd by the time I was done I had toasted the bit. Oh well...

Now if only I had measured all four mounting holes to make sure they were the same distance apart. Who would of thought they would be 10" apart a 11" on the top?

The touch screen is much easier to use now with it mounted rigidly. I am reusing a lot of the buttons from the old panel, many in their original location. I ordered a piece of aluminum today for the overlay to cover all the holes and the rough cut edges.

When I was setting up the front panel I had a little accident. I crushed the reader head on my X axis Heidenhain slide. The overtravels were not working as I was still waiting for the second parallel port card. Anyone have a spare Heidenhain LS403?

I found out the computer I picked just isnt going to hack it. i cant rapid a anything past the 35khz setting im mach without it jumping around. I have an old P4 2.4 SFF pc that I was going to use for another project. Its kind of like a shuttle PC. One PCI, One AGP and not much more. I had gone to urn it on a month or so ago and the power supply blew up. I called FIC about a new power supply and they wanted $65+ shipping. Forget that!

I endup just getting a generic P4 ATX type power supply at goodwill for $2 nd set it on top of the machine. I got a dual port PCI card from ebay and installed that. Reinstalled windows and all the drivers and replaced the old computer. This made quite a difference. Not only can I run in the 45khz setting but going into wizards dosent kick in the driver watchdog. Also I can rapid much faster now. I was limited to about 120 ipm and now I can do 180 on X and 150 on Y.

Now that I have the second parallel port installed I also have my home switches and overtravels working. The mill has some nice switches installed. So far they are totally repeatable and have hit the exact same spot everytime I have home the machine.

I also hooked up the linear slides to the second port... Well, the two that are left... So far it looks like my Y axis is ending up where it should be withing a couple tenths everytime and I have about .0008" backlash. I also found out I had my Z setting way wrong! by 20%. I had thought the Z ball screw was .2" pitch like the others but it is actually .25 pitch. Also the Z screw is showing quite a bit of wear as it seems a little drunk. I will have to try the screwmapping and see if that helps.

My next project is to add spindle feedback. I picked up some Keyence retroreflective fiber optic sensors that I am hoping to be able to pick off a mark on the spindle and get it to stop in a certian position to do the back boing canned cycles. Also to compensate for load while cutting.

At this point the panel is mostly designed. The only thing I am waiting for is I need to come up with something to do mouse clicks. The toucscreen driver does have an option fot right clicks but does not work very well. I think i am just going to take a cheap mouse and gut it for the circuit board and mount some panel switches in place of the old switches.

Here are a couple more pics of getting ready to cut the hole for the display and the finished prouct.