Hold the phone - I made a mistake
When I wrote up the subject of this thread I made a mistake. The mistake is in the calculation of the scoping torque required to engrave brass. The error is in my selection of the feed per tooth. I used 0.18 mm per tooth. I should have used 0.01 mm per tooth!!!!!
I found this out in a conversation with the gentleman that wrote the article which had the torque equation. I found the initial value of 0.18 mm per tooth in another referance. I only read one page and should have read the other 65 pages.
Backing up - I was calculating the torque required to engrave brass with a pointed engraving bit. The bit has a 60 degree included angle, and the depth of cut is 1 mm. Assume a rpm of 20,000. So re calculating:
1 mm depth of cut
1.16 mm width of cut ( up 1 mm from the point )
0.01 mm per tooth feed per tooth
2 teeth number of teeth
0.29 machinability factor for brass
0.0077 N-m Torque
0.77 cN-m Torque
462 mm per min Feed rate
18.2 inches per minute
Big difference in the resulting torque required. I guess the PROXXON might work. But may not hold up to a continous duty cycle, as Tokyocrow pointed out. But for the money, Tokyocrow has found better alternatives.
I got the new feed per tooth of 0.01 mm from the assumption of 1 percent of the tool diameter (1.16 mm) per tooth.
Whelen
Have you made your high speed spindle yet?
I have just found this forum and fairly new to the mini cnc scene. I also have been trying to come up with a high speed spinde for my mini-mill. I have the grizzly version of the Seig x2 which I have converted to cnc last year.
I have been engraving some small items and I cant do a very good job with small cutters at the 2500 rpm the mill tops out at. I read the entire thread and looked at most of the links.
I find the mini air spindle an intriguing possibility, except for drilling a hole in the drawbar (although if a long hollow bolt could be purchased, it may be easier to set up).
I have a harbor frieght trim router that I had thought about using, but it is too long to fit under the mill head and mounting it on the side would be ok, except for the loss of working area.
Has anyone considered mounting a DREMEL high speed grinder, using either: the flexible shaft attachment (maybe it could be fed through the spindle?) or the right angle attachment, mounted under the millhead?
Since it is mainly for engraving, I would think that the power would be sufficient and the speed is adjustable (usually 0-35,000 rpm).
If anyone has thought about this, or something similar, any help would be appreciated.
I found my high speed spindle solution
Halfnutz, I found my high speed spindle solution. Or I should say KDN Tool found it. I wrote it up on 8-2-06 in Benchtop Mills titled - High Speed Spindle for SIEG X2 - I found it.
8-2-06 "High Speed Spindle for SIEG X2 - I found it". 5,000 to 20,000 rpm with six collets 1/32" to 1/8" - for $170, which includes the mounting bracket for the SIEG X2. You will find it on [url]www.kdntool.com[/url]
Bill Perun
Need advice w/minitech mill
I recently bought a minitech mill, used. i haven't been able to get it to respond to any software. I'm pretty green to the cnc world here, that's why I'm here.
i've connected the mill and can here the fans running, but i'm unable to get mach 2 or mach 3 to respond or jog any of the axis.
Can anyone help me determine if i have a driver problem or if it's just my misuse of the software.
This mill checks out mechanically and looks to have been hardly used,according to the ball screws and the overall condition. Mecahnically everythting moves and appears to be in good condition.
i have entertained the option of replacing the controler and the steppers, which will still leave me under what i could buy one of these mills for.
I really don't want to spend unecessary cash for parts i don't need , if i don't have too.
Remember, I'm a novice and very green. So please be easy and help me .
Thanks
mark
Wolfgang Spindle /Minitech Mill
Thanks for the reply...
Since I posted that- about the spindle, I have ordered a spindle from Wolfgang, I have not incorporateded it into the mill yet. I am constucting a small mill to use it with. The spindle lookg stout enough to do some serious machining of small metal parts. I think the X2 will be too loose to get good work, but I have a small bracket, I may mount it up to do some engraving.
If anyone has used this Wolfgang spindle- please share your experiences.
About the minitech mill, since you are new, my suggestion is you investigate the type of controll the mill has-
Is it a PC type Parallel port ? or a serial Port? sometimes the 25 pin d-sub type connector is used for either one. a 9 pin is usually a serial port and rarely a parallel port.
Second- if it is a parallel port, you need to determine the step pin and direction pin for each motor axis.
Mach 2,3 use two pin signals for each motor axis. You can configure which ones are used within the software in order to match up to your machine.
The best way to get this information, about your machine, is to get the original documentation. Without that- it will be difficult.
If you cant get documentaion, you could examine the connector to see which of the 25 pins are used- sometimes the non-connected pins will be missing from the housing. If it is connected to a pc board- you can see if they are connected to circuit traces or not. Check this with the power off of course.
Good luck.
MiniTech don't sell CNC machines
Hi Mark,
MiniTech only sell the base, manual machine. What you have is one that has been modified by someone.
You don't need 'minitech drivers' there is no such thing. So the Minitech guys, even though they are very helpful, cannot help you at all.:(
Get onto the Artsoft Mach3 site ([URL]http://www.machsupport.com[/URL]) and check out their tutorials, they will give you information on how to set Mach3 up and also info on setting up the port pins etc.
If your steppers are locking up when you have power to the drivers then it sounds like you're half way there, you just need to get the PC/Mach3/Driver interface working - which should not be too hard (I note you are a complete noob, but trust me) :).
Whatever you do, do not rush into this, take the time to ask as many questions as it takes before you know what you are doing or you may fry your driver(s) and/or PC.:nono:
What driver(s) do you have to drive the stepper motors (I'm assuming they are steppers and not servo motors). Some common ones are Xylotex and Gecko - or in your case someone may have built a driver from an Oatley Electronics kit (check out [URL="http://www.oatleyelectronics.com"]www.oatleyelectronics.com[/URL] and look for stepper motors/kits).
Mach3 does some things that Windows doesn't know about, so look on the Artsoft web site for instructions about optimising XP to let Mach3 run correctly - if you have other things running that clash with Mach3 Windows won't know what is going on. Basically you can't have anything else (even a screen saver) running while you have Mach3 running, it's best to have a dedicated PC for Mach3 (ie don't use the PC for anything else). Also check out the minimum PC requirements for running Mach3, you'll find that on the Artsoft site too.
Getting back to your question, it sounds like XP has detected that signals are getting to the PC from the driver board(s) and thinks you have some sort of printer attached, this indicates that it may require rewiring the connection between driver and parallel cable - one thing to check is that you have a straight through parallel cable with all pins connected, some cables don't have all wires connected and some cross a wire or two getting from one end to the other. Check for continuity with a multimeter (set on Ohms) between pin one of one end to pin one of the other end - do that for all pins, you should see zero Ohms in each case - if you don't, get another cable.
You will need to get info from the driver maker to be sure that the connections to the parallel cable are correct, if they are OK and your cable is OK then it should be easy to set up the port pins in Mach3 - and away you go. ;)
Good luck and Cheers,
Dave.
drivers[quote=gone4pepsi;229254]When i booted up my pc, xp told me I had new hardware and was looking for the drivers. i unplugged the paralell cable, rebooted, and now i don't see xp looking for the drivers. any ideas? Does minitech require it's own drivers,or do you think this is a glitch in mach3 or my pc?
Thanks
Mark[/quote]
Minitech mystery machine-
Mark,
If what finance says is correct, you are left with no other choice than to open up the controller box and look at the circuit board. Hopefully you will find a name on it, maybe also a model number, and you can "Google" it to get information on the internet.
Then maybe you can get the manual. Just be sure to unplug it first and groung yourself by keeping one hand on the metal of the box, or by not touching anything- basically the same static electricity precautions you would have while working on your PC.
If you cannot fins a name - you can take a good picture of it and post it on this thread- or start a new one.
Rustfinger.
Minitech Does support their machines
[quote=finance;238000]Hi Mark,
MiniTech only sell the base, manual machine. What you have is one that has been modified by someone.
You don't need 'minitech drivers' there is no such thing. So the Minitech guys, even though they are very helpful, cannot help you at all.:(
Get onto the Artsoft Mach3 site ([URL]http://www.machsupport.com[/URL]) and check out their tutorials, they will give you information on how to set Mach3 up and also info on setting up the port pins etc.
If your steppers are locking up when you have power to the drivers then it sounds like you're half way there, you just need to get the PC/Mach3/Driver interface working - which should not be too hard (I note you are a complete noob, but trust me) :).
Whatever you do, do not rush into this, take the time to ask as many questions as it takes before you know what you are doing or you may fry your driver(s) and/or PC.:nono:
What driver(s) do you have to drive the stepper motors (I'm assuming they are steppers and not servo motors). Some common ones are Xylotex and Gecko - or in your case someone may have built a driver from an Oatley Electronics kit (check out [URL="http://www.oatleyelectronics.com"]www.oatleyelectronics.com[/URL] and look for stepper motors/kits).
Mach3 does some things that Windows doesn't know about, so look on the Artsoft web site for instructions about optimising XP to let Mach3 run correctly - if you have other things running that clash with Mach3 Windows won't know what is going on. Basically you can't have anything else (even a screen saver) running while you have Mach3 running, it's best to have a dedicated PC for Mach3 (ie don't use the PC for anything else). Also check out the minimum PC requirements for running Mach3, you'll find that on the Artsoft site too.
Getting back to your question, it sounds like XP has detected that signals are getting to the PC from the driver board(s) and thinks you have some sort of printer attached, this indicates that it may require rewiring the connection between driver and parallel cable - one thing to check is that you have a straight through parallel cable with all pins connected, some cables don't have all wires connected and some cross a wire or two getting from one end to the other. Check for continuity with a multimeter (set on Ohms) between pin one of one end to pin one of the other end - do that for all pins, you should see zero Ohms in each case - if you don't, get another cable.
You will need to get info from the driver maker to be sure that the connections to the parallel cable are correct, if they are OK and your cable is OK then it should be easy to set up the port pins in Mach3 - and away you go. ;)
Good luck and Cheers,
Dave.
drivers[/quote]
I beg to differ. Yuo are wrong, everything on this mill is minitech.
Jack has contatced me everyday since i posted at the forum for mach 3 software. Art tried to help, but had no idea about Jack's machines.
Jack walked me throuhg everything and after trouble shooting, we have come to realize that the board was bad.
FYI the board says Mini tech right on it.
After configuring the pins, it came down to me isolating the drives whith each motor..
There was no one at the mach 3 forum that was of any help , with the exception Of Jack from Minitech.
Art tried to help, but had no idea where the problem could have been..
The original problem was in the software.
Jack researched it for me and emailed me the information , and finally after days of deliberating we unchecked all of the active lows to all the axis and bingo we had a response.
Jack offered to salvage a board from an older machine.
I've decided that i'm just going to upgrade to a bipolar controller and higher torque motors.
If anyone is inteested, These motors are the oriiginal and have been tested. I've have no idea what the holding torque is, but they are all equal and in excellent condition
They are unipolar, six wire and i'll let them go real cheap.
If anyone needs help with an older minitech, i'm sure Jack will be more than happy to hear from you. Just email him.
Mark
