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Buba b
23-06-2020, 09:14 PM
So i finally had enough of Mach 3 and while sitting with a broken collar bone i got carried away ! So i splashed the cash on new Adtech 9640 controller while on pain killers and this turned up a month later . Some months later i decided to use it and then got confused again !.

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So my problem is making it count to 10 , its a recurring problem I've had with all the systems I've ever put together :numbness:.
The Am882 are set to 8 micro stepping on 5mm pitch screws , I test cut at 55mm long and get 58mm at the moment .....so

Gear numerator / Gear denominator = P ( L x 1000 ) = a magic number

5x1000=5000/1600 =3.20

Its just that I cant get a decimal point into the Gear denominator parameter which means I've messed up some where !

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Anyone have experience of setting these controllers up
Someday this will cut metal ........... just not today !
Thanks :tennis:

dazp1976
23-06-2020, 10:24 PM
Is 8 micro stepping equivelent to 1600? Can't remember.

Well in Mach3 for example you'd:
1. Have 1600 per rev on the drive.
2. Then divide that by the pitch (5)..
3. Mach = 320 per unit.

How that system you have now works is beyond me.
Do you have any documentation for setting it up?


Is that power drawbar custom built?
Looks good and I wouldn't mind having the drawings for future reference if poss :)

johngoodrich
23-06-2020, 10:32 PM
I agree with daz above. I had a look at the manual and it doesn't say what the numerator and denominator are meant to be or for that matter P and L in your equation above. I would presume the numerator would be the steps per rev(1600) and the denominator would be the pitch of your screw(5). What figures have you got in there already to make it move 58mm?

Buba b
23-06-2020, 10:56 PM
So I've just sorted my duff maths in first post ! And it proves I can't make tea and post at the same time , anyways the manual gives an example of a servo :
Motor rotates one cycle every 5000 pulses and tool moves 10mm
CMR/CMD = 5000/(10x1000) = 1/2
CMR : Gear ratio numerator
CMD : Gear rato denominator

I'm running at 1/3 which gives me the 3mm over run , if your right and I need to put in 1600/5 then that would be great as I wouldn't have to frazzle my brain with maths. They just look big numbers compared to the manual and I never thought about it that way . Il try tomorrow see what happens .... Can't be that easy , it's Chinese !
Thanks

johngoodrich
23-06-2020, 11:02 PM
So I've just sorted my duff maths in first post ! And it proves I can't make tea and post at the same time , anyways the manual gives an example of a servo :
Motor rotates one cycle every 5000 pulses and tool moves 10mm
CMR/CMD = 5000/(10x1000) = 1/2
CMR : Gear ratio numerator
CMD : Gear rato denominator

I'm running at 1/3 which gives me the 3mm over run , if your right and I need to put in 1600/5 then that would be great as I wouldn't have to frazzle my brain with maths. They just look big numbers compared to the manual and I never thought about it that way . Il try tomorrow see what happens .... Can't be that easy , it's Chinese !
Thanks

I would say yes it seems that would be right from their example, apart from where they put =1/2 because that doesn't add up but that could just be because its Chinese translation give it a try and let us know

JAZZCNC
24-06-2020, 01:12 AM
I haven't seen the manual but I think you may be using the wrong parameter. Usually, Numerator/Denominator relates to gearing, it's often used in servos for electronic gearing.
So in your case, if you have no gearing then it will be 1/1. The actual pulse setting I'd expect to be in another parameter, often it's the encoder pulse parameters that dictate the output pulses per unit(mm) so it could be you need to enter 320 into the encoder parameters.? (might need to divide this by 4 if the parameter expects encoder base count as it will multiply x4 as it will assume your using quadrature encoders.!)

But without seeing the manual I could be way off.!!

johngoodrich
24-06-2020, 07:18 AM
Listen to jazz. He knows what hes talking about

dazp1976
24-06-2020, 03:39 PM
I haven't seen the manual but I think you may be using the wrong parameter. Usually, Numerator/Denominator relates to gearing, it's often used in servos for electronic gearing.
So in your case, if you have no gearing then it will be 1/1. The actual pulse setting I'd expect to be in another parameter, often it's the encoder pulse parameters that dictate the output pulses per unit(mm) so it could be you need to enter 320 into the encoder parameters.? (might need to divide this by 4 if the parameter expects encoder base count as it will multiply x4 as it will assume your using quadrature encoders.!)

But without seeing the manual I could be way off.!!

I was thinking that last night.
The gearing is for if you are driving your motors/screws with reduction such as 2/1 belt & pulley. 1/1 being direct drive with no pulleys.

m_c
24-06-2020, 07:22 PM
I think you need to change the encoder wire parameter (2-29)

I did try attaching the PDF, but I think it's too big for the forum to accept :-/

Buba b
24-06-2020, 07:25 PM
So I've had a little play and its still not playing ball but its hotter than the sun in my garage at the moment and il have wait until its cooler then hit it.
By memory in the Fanuc manual the numerator and denominator are used for gear reduction and in the Adtech the manual states :

" When screws of different pitches and motors of different step angles or servo motors of different pulses are matched or connected through gears it allows keeping the program and actual motion distance consistent through electronic gear ratio setting of the system. "

So I've thought this meant by the first part of the statement that the motors and pitch ( with the calculation ) would be needed for the setup but you could also read into the second part , that this setting is for gearing the motion . Even reading Fanuc manuals usually leaves you scratching your head if you overthink the use of English and this manual is no better.
With the quick go the 1/1 its not even close to measurement and 1600/320 was interesting until it didn't move at all , but i need to get in and play more when cooler and have another scan through the manual .
Thanks

JAZZCNC
24-06-2020, 08:51 PM
With the quick go the 1/1 its not even close to measurement and 1600/320 was interesting until it didn't move at all , but i need to get in and play more when cooler and have another scan through the manual .
Thanks

That's about what I would expect with using steppers because the Encoder parameters will be much higher, probably something like 2500 by default, which is a standard Encoder base count. This could also easily be x4 because encoders are quadrature and it probably uses the base pulse rate.

If you can point me to the manual I'll take a look.

m_c
24-06-2020, 08:59 PM
Jazz, YGM (or you should have, unless it's gets bounced back for being too big!)

JAZZCNC
24-06-2020, 09:29 PM
Jazz, YGM (or you should have, unless it's gets bounced back for being too big!)

Cheers M i'll take a look later.

JAZZCNC
24-06-2020, 10:20 PM
I think you need to change the encoder wire parameter (2-29)

I did try attaching the PDF, but I think it's too big for the forum to accept :-/

Ok I agree with M_C try setting parameter (P2) 29 to = 80. This is 320 / 4

Buba b
25-06-2020, 09:27 PM
I changed the 2-29 to 80 and the Num / Denom to 1/1 and no change still out but I'm going to have a look when I've got time at the weekend .
So just for interest I found a blog with a guy setting up a Newker control , cant believe it much different and he's setting up a 4th axis with a stepper motor

https://mightyshiz.blogspot.com/2018/01/parameter-setup-for-4th-axis-newker-cnc.html

He says :

"The units are important too. I have 2000 steps per turn set up on the stepper driver and the controller seems to generate 4 pulses per "step", so I need 8000 on the numerator and 1900 on the denominator (# in "axis" parameters). Not clear quite how all that works but certainly, the indicated units for the A axis correspond with degrees movement on the table."

Now i haven't got into reading too much yet but it was interesting that he's got the big numbers in numerator and denominator rather than the 1/1 .
So I'm going to bash google as I cant be the only muppet running one of these with steppers ......or can I .....hmmm!
Thanks

Some guy called Muzzer ?? .....now where have I seen that name before !