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Wasnt really sure where to put this but its related to the spindle so ill try here. Seems that edge finders like to run somewhere around 1k to 2k rpm. Obviously not an option for these chinese spindles that dont like to run under 6k. What are some other options? A haimer would be sweet but i think thats just way too much tool for me this early on. Suggestions?
I was going to say a Haimer. I want one. But you can try a electronic edge finder. I have one by Fowler. Simply lights up when you touch. Takes weird batteries though.
There are a few options,Quote:
Originally Posted by QuinnSjoblom
Laser https://lasercenteredgefinder.com/
Led Beep Led Beep Touch Point Sensor Precision Electronic Edge Finder CNC Machine Milling | eBay
Probing there are some really good probes now available here is one
https://www.youtube.com/watch?v=HeiRGc0eJUA
Why would you think it is an issue to run the spindle at less than 6krpm? I mean seriously, don't believe everything you read on the Internet. NOTHING will happen if you run the spindle slower. It will not have a lot of torque but it is not really needed here, so why worry? In any case, you can always use electronic edge finders, touch plate types are the simplest, or many other types which are more complicated and expensive.Quote:
Originally Posted by QuinnSjoblom
I think a simple touch probe is a cheap alternative that works very well. You don't say what driver software you are using, but if it's Mach or UCCNC both have great probing routines available with options for a number of different probing types.
Interesting. Yeah I'm just going off of everything I'm reading and the common recommendation for minimum frequency setting is 100hz. Makes sense that it would only apply if spindle is under load. So I'm fine to drop it to 1k or so as long as I'm not cutting?Quote:
Originally Posted by A_Camera
I have a 1.5kw air cooled spindle and I run at 2000 rpm no problem with a 3/8 edge finder
Ok. Good to know. I think eventually I will get a haimer just because it's useful for so much but for now I'll just throw a regular edge finder on and slow the spindle downQuote:
Originally Posted by sparkness
And you should to be safe, the photo below is what happens when run to a speed that you could use an edge finder, which is 800-1000 RPM and edge finder would be not accurate above this speedQuote:
Originally Posted by QuinnSjoblom
You don't have to be cutting, they draw a lot of current when running slow and over heat very quickly, and before you know it they are damaged, the manufacturers has a written specification as to how slow they can run safely and if you look at the Manufacturers site ( not the Sales site ) you will find the minimum RPM for your spindle, almost all that run with a Max of 24,000 RPM only have a minimum of 6,000 RPMQuote:
Originally Posted by QuinnSjoblom
I only run at low speed for a very short time to edge find .Get within a thou, spindle never gets warm. I use this mainly when I put the vise on the router table and set a G55. I will look at the amp draw next time I need to zero
Seems like the easy solution that won’t stress your spindle is the electronic edge finder
They aren’t expensive either.
I just finished peck drilling a huge number of 3.2mm and 4mm diameter 18mm deep holes in aluminium at 9krpm. OK, that's more than 100Hz, but I am normally happily drilling in POM (Delrin) at 5k as well with my 1.5kW air cooled spindle and the spindle is well below 40C all the time. 6k is the minimum specified speed but nothing will happen if you spin it slower. All you need is the torque to rotate the probe, which I guess is considerably less than drilling in plastic needs, so I am pretty sure you are safe to spin at 1k, assuming the motor can rotate that slow. I think that depends not only on the motor but also on the VFD, but you will easily see if the motor rotates or not, double the speed if it is not rotating.Quote:
Originally Posted by QuinnSjoblom
Certainly that didn't happen with no load rotation, or the motor was crap already even before.Quote:
Originally Posted by mactec54
That's nonsense. They draw practically NOTHING at slow speed unless you run in vector mode.Quote:
Originally Posted by mactec54
Definitely the best solution. Not because of the "stress of the spindle" but because it is better.Quote:
Originally Posted by ianagos
It happens almost every day, that one happened on startup, less then 20 seconds run time, when they set the minimum Hz Parameters incorrect, go through some of the post on smoked spindles and VFD DrivesQuote:
Originally Posted by A_Camera
I run some tests after I posted those comments yesterday. It was very late so I only run a few minutes tests with several RPM and never ever got the current above 0.6A. There is no way I believe that after a few seconds at low RPM you can burn any motor. Something else must have gone wrong in your case, but of course, if the VFD is wrongly configured then that may fry the spindle. My VFD is configured for 10Hz minimum frequency but it will not start rotating below around 200 RPM. Anyway, I run tests yesterday at 500, 1000 and 2000 RPM for several minutes and nothing happened. I am monitoring the VFD and the spindle, so I have the data for several critical parameters, which means that I know the health of both. The spindle was luke warm (30 degrees C), but remember that I drilled a lot of holes and milled aluminium for several hours before the test. I guess that if I would have started at room temperature it would have stayed there for hours.Quote:
Originally Posted by mactec54
One thing you have to remember you have a high quality VFD Drive, Not all VFD Drives are created equal, what works for you won't work, the same for others, that was not my spindle that was smoked, I could show you lots that look just like it, the main problem when this happens, is they have the wrong parameter's set and when they run it lower than the manufacturers minimum speed, this is when this happens and on startupQuote:
Originally Posted by A_Camera
I make a habit of testing stuff when i buy them. With my 6040 i received those water cooled spindles and cheap Chinese drives. Used to run the spindle without cooling and at slow speed....no issues, no overheating. However i did not like the drive, looked like it came out of a toy factory. Replaced the spindle with a router (Kress). My old drive and spindle went to a mate, both his drive and spindle burn't out very soon after he started using his 6040. He had no problems with my stuff. Seems its just hit and miss with these Chinese drives and spindles:)