Machsupport Forum
General CNC Chat => Show"N"Tell ( What you have made with your CNC machine.) => Topic started by: davepag on August 08, 2008, 11:30:13 AM
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It's getting there!!! Finally getting movement -- thanks to Mach3.
Consider it a Green Machine...(with the exception of the controller components and the router) it's made of recycled parts from scrapped machinery and materials.
(http://emxdesigns.com/cnc_router/Aug01_0001.jpg)
(http://emxdesigns.com/cnc_router/Aug01_0002.jpg)
(http://emxdesigns.com/cnc_router/Aug01_0003.jpg)
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Looking good Dave, looking good. Look forward to seeing a video of it whiping around automagicaly. ;D
Brett
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Nice machine Dave - looks like you have built it to last.
What diameter are the Y axis rails please ?.
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Nice machine Dave - looks like you have built it to last.
What diameter are the Y axis rails please ?.
I'll say, it's a beast! Nice looking work, Dave-
Dave
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Looking good, but it will even feel better when the first work of art is removed from the machine.
RICH
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The Y axis rails are 1" diameter. Got the Y ball screw and drive installed and running yesterday. Initial tests are going nicely! Mach3 is running smooth on Windows Server 2003.
Question to the masses...any reason why bringing the proximity output voltage (12VDC) down to 5VDC with a potentiometer is a bad idea?
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The Y axis rails are 1" diameter. Got the Y ball screw and drive installed and running yesterday. Initial tests are going nicely! Mach3 is running smooth on Windows Server 2003.
Question to the masses...any reason why bringing the proximity output voltage (12VDC) down to 5VDC with a potentiometer is a bad idea?
Using a potentiometer set up as a voltage divider is OK as long as the switch can supply enough current for the potentiometer. You could use a couple of resistors instead, that way you won't accidentally move the pot and supply too high a voltage to you 5V input. you could make a voltage divider from a 6.8K and 4.7K resistor. At the junction you would get 4.9V when feeding it with 12V.
The higher the voltage you use for switches sensor the better. Well to a limit. :-) A system using a higher voltage is usually less susceptible to noise as the noise is a smaller percentage of the overall signal. Also for mechanical switches, there is some voltage loss across the switch due to resistance in the switch contacts. Additionally, a higher voltage cleans the switch contacts better when it closes.
There is a reason why industrial systems use 24Vdc for their signalling. In the end you need to get it down to 5V to get in/out of the parallel port, and it is best to do this close to the PC.
Cheers,
Peter.
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hello, your work is very intersting and you can be proud. just a thought on the recommended voltage devider, consider the wattage rating for the resisitors, I always tend to over build, so what ever the current to flow through them, i would step to a higher rating for them.. from an old man from the days of tube type computers, etc. :D
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I wonder what 'tube type computers' are exactly ?.
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They used vacuum tubes instead of transistors/chips etc. Tubes looked like miniature inverted milk bottles. From an old guy who remembers glass milk bottles and chips were from a deep fryer.