Machsupport Forum
Mach Discussion => Mach3 under Vista => Topic started by: sbloom67 on December 21, 2019, 11:02:09 PM
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So forever I have been trying to get my cnc machine working. I am using mach 3. I have tried setting up the spped of the movement of the access of anywhere between 800 and 1200mm per minute. I have also made my acceloration between 5 and 10% the speed. When I manually tell the x or the x or the z to move it all seems fine. But when I run a small program with lots of moves the machines has lots of problems and I loose steps and the machine seems to shutter. I am running the steppers at 1/2 step and have the step and dir pulse set at 15 each. I have 3 power supplies,1 for each y and 1 total for the x and z. I also have a separate 24 volt one for the Break out board, I do notice that the voltage starts to go down on the powere supples as they go on. Any ideas ????
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1/2 step is not good for smooth movement - it is more usual to use 1/8 or 1/10.
Could you post more details of your machine and controller - a couple of pictures would be good.
Tweakie.
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It is a custom machine. I built from scratch. It has 425oz motors and 4 controller that are set at 4.2amp. It has one of those inexpensive break out boards that attached to my parallel port. I am running win 7 32 bit.
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But when I run a small program with lots of moves the machines has lots of problems and I loose steps and the machine seems to shutter.
Post the following:
1. Stepper motor information - from who, model number, motor curve, etc
2. Drive information
3. Screw information
3. Power supply information
4. XMl file you are currently using
5. The program you are using ( complete not snippet of code )
The above information will save us a lot of time. I'll refrain from making comments until the above is posted.
RICH
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Motor is Act motor model 23HS2442
Driver is HY-DIV268N-5A. It is set at 1/2 step and 4.2A
screw is 8mm screw. one turn moves it 8mm
https://openbuildspartstore.com/8mm-metric-acme-lead-screw/
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Power supplies are DROK Adjustable DC Power Voltage Converter AC 110V-220V to DC 0-48V Module 48V 10A
https://www.amazon.com/gp/product/B01MV4249T/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
XML FILE - I have no idea on what you mean by this
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and finally the code
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XML FILE - I have no idea on what you mean by this
The profile you use or created to run Mach3 is located in the Mach3 directory on your computer
and is saved as an XML document. It contains all the settings etc. you defined for the machine.
Make a copy of that file and rename it to have a unique name ie; NEED HELP and post it.
RICH
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I believe this is it.
Thanks Steven
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has one of those inexpensive break out boards
Post info on the break out board
Can you post a link to where you purchased the stepper motors from.
The ACT company does not list that particular model stepper.
RICH
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This is the instructions for the BOB.
I don't have the info anymore about the purchase of the motors
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found this. hope it helps
https://es.aliexpress.com/item/32793492142.html
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Hi,
those steppers have 3.8mH inductance, its too high for reliable operation at speed, look for steppers with half, or less if poss,
inductance.
Craig
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Do you have a suggestion for motors that are similar but fit the need on inductance.
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Hi,
there are many manufacturers most of whom will have very similar steppers....all you have to do is select the low
inductance ones.
Typically low inductance steppers have a high current rating for the torque they produce because they use fewer turns but a larger diameter wire.
This tends to result in high current but comensurately low inductance.
First time buyers look for the highest holding torque but overlook inductance, manufacturers know this and produce high torque motors
but have high inductance and consequently lose steps or stall above a few hundred rpm.
Its common to have from one manufacturer a 570 oz.in stepper say, and a 450 oz.in one say, both the same size. The stronger one is better right?
Well maybe not...the lower torque unit has low inductance and will still be producing useful torque at 1000 rpm whereas the high torque unit
will have stalled at 400-500 rpm.
The main way to counteract the adverse effects of inductance is to have the highest possible voltage drivers and power supply. At the current time the
highest voltage drivers readily available are 80V. I would recommend them. You need to match it to an 80V power supply, a transformer type is
preferred over cheaper switch mode supplies.
Craig
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Hi,
this is an example:
http://www.leadshine.com/productdetail.aspx?type=products&category=stepper-products&producttype=stepper-motors&series=CM&model=D57CM31 (http://www.leadshine.com/productdetail.aspx?type=products&category=stepper-products&producttype=stepper-motors&series=CM&model=D57CM31)
439 oz.in at 6A but only 1.18mH. This will produce good torque right out to 1000 rpm or higher.
You might look at Leadshine's AM882 driver while your'e there, 80V and up to 8.2A
Craig
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I finally got it working. I went from 1/2 step to 1/8 step and slowed down the speed to 500. No more issues !!!!!!!!!!!!!!!!!!!!!!!!!!!!!
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Happy you got it working. :)
If as is, the machine provides the quality of machining for whatever work you will do with it, then that is what matters.
For a test do a simple square and triangle with the sides equal to 0.7 mm in length running at F500 and see what happens.
RICH