Digital read out interface

[black85vette]

I noticed on my digital calipers that there is a little door and an electrical connection. It looks like the DRO scales and digital calipers can feed a remote display. Now the geek question; anybody know what the output is?? I am guessing serial data but 5 volts, RS232 or ??? Have not had a chance to hook up a scope and see what it looks like. Thinking maybe someone already had the answer.

 

[ke7hr]

I have looked at this project, but not taken it on yet...

http://www.compendiumarcana.com/caliper/

I bought three cheap calipers thinking I will make a homebrew DRO for my little three in one machine. Maybe the way the link did it or use a PIC.

 

[techonehundred]

Try this link and see if the information is here.

http://www.piclist.com/images/boards/guage/index.htm

 

[ke7hr]

Another link with good information:
http://www.shumatech.com/support/chinese_scales.htm

 

[black85vette]

Thanks to both. The info is about the same but the second link has the schematic with it. This is exactly what I was looking for.

I was also interested in this:

http://www.littlemachineshop.com/products/product_view.php?ProductID=2222&category=-1536942993

Go to the web page and hit "Chris's Tips" This appears to have a rotary encoder and display in a single unit. Rather than a linear encoder measuring movement it measures rotation of the handle and computes the distance. They have this for the 7x10 lathe but I have not seen anything like it for the mills. Looks like it would be a good set up with no wires or brackets.

 

[ke7hr]

I looked at the DRO from Little Machine Shop but wonder about how it handles the backlash problem. With external scales that only respond to table (quill, cross slide, etc.) actual movement, I think it would be more accurate.

 

[black85vette]

ke7hr; that is a good site also. Got it bookmarked. Thanks


Looks like engines might get delayed to fit in an electronics project.

Re: backlash. I am pretty sure you would use the rotary DRO more like the dial mounted to the table and read it in the same direction every time. I would take that drawback over the cables and price of a remote readout.