Brother TC-211

mblaszkiewicz wrote: I was wondering if it could be a metric ball screw

I would be amazed if it wasn't a metric ballscrew.

Doing some basic math on the results I got in my checking it appears that the pitch is based on metric dimensions. It is written as a 5 tpi ball screw, but if I use 25mm instead of 1 inch (.4 mm) difference. I found my .015 error. .4mm equals. 0157 my present error. How would I adjust my encoder count to fix this? ???

if this is a metric ballscrew it will be 25mm x5mm pitch , what encoder is fitted and it will have x counts per turn either in the part number or in the manual
are you setting the machine in Imperial or Metric , the easyiest way is if the machine is metric then set the machine units in metric also

can you give details of encoder fitted ?

the confusion will arise if you try to set up the machine in imperial inch when it is a metric machine , their will always be an error due to rounding

It is a 1024 count ppr for the encoder. As with a few other things the manual is off a little. It says it is a 5 tpi.
With the metric ball screw and imperial measuring how would I adjust the encoder count so it is correct. I'm really not would about making everything metric or re writing the whole Hal file.

the encoder will look after it's self as it's based on turns and not distance it knows nothing , i cant see it being a metric ballscrew and having turns per inch ,so it will be a typo in the manual
the standard ballscrew at 25mm will be either 5mm or 10mm pitch ( or per turn etc ) just set the machine up as metric , so the scale would be per mm as against per inch ,
so 1024 per rev ,@ 5mm per rev , so divide 1024 by 5 so scale = 204.8 ( per mm ) if you find the distance is out just add a small amount to the scale , or juggle the encoder or scale to suit , after checkiing distances traveled over say 200 mm or more
to get an idea of accumulated error

doing this in imperial would give you
would make it 5.08 tpi (25.4mm per inch / 5)

mblaszkiewicz wrote: I'm really not would about making everything metric or re writing the whole Hal file.

You can display positions in either unit, and use G-code in either units, so it doesn't make an enormous difference what the "native" units of the machine are.

But, if you have set it up for 5tpi and 1024 count encoders then the ENCODER_SCALE in the INI file is probably 5120.
It might well actually be 20480 if the spec is slots rather than edges.

If it is actually 5mm pitch then it takes 5.08 turns (exactly) to move one inch, so you need to change the ENCODER_SCALE for each axis to 5201.92 (or 20807.68 )

Because the inch is now defined to be exactly 25.4mm these should work out exactly right, and no danger of accumulated error.

Ok thanks to everyone. My machine now moves exactly like it is suppose to. And Back lash is good. Under .0002. now I just need a little help to make sure everything is tuned (servo's) I haven't been able to get it figured out yet, so any help would be great. Also I really would like the machine to speed up alittle. It maxes at 60 ipm. looking for closer to 600 ipm rapids and 200 ipm cutting

mblaszkiewicz wrote: Ok thanks to everyone. My machine now moves exactly like it is suppose to. And Back lash is good. Under .0002. now I just need a little help to make sure everything is tuned (servo's) I haven't been able to get it figured out yet, so any help would be great. Also I really would like the machine to speed up alittle. It maxes at 60 ipm. looking for closer to 600 ipm rapids and 200 ipm cutting

Is that speed limit where you get following errors, or where it maxes out?

It is where it Maxes right now. I still have following error at one inch

mblaszkiewicz wrote: It is where it Maxes right now. I still have following error at one inch

What happens if you increase the max velocity? (I am still not sure what problem you are describing)