Author Topic: DIY bluetooth DRO for my mill  (Read 1456 times)

Offline PekkaNF

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Re: DIY bluetooth DRO for my mill
« Reply #25 on: April 25, 2022, 09:08:43 AM »
Thanks Pekka. I do have a big micrometer, I was thinking I'd have to make a bar up with it, but if I have a cal rod with it, I'll use that. In mounting, I've been very careful not to bind the scales in any way, but we'll see.

I think friction or binding error would show up as scale reader backlash, in other words not returning to the same point after a traverse and then reversal, vs calibration error which would show up as a one directional measurement error.

The main thing I'll be looking for, after calibration adjustment would be inconsistencies for traverses of varying lengths and their returns. That should show what the limits are.

I think I remember reading something somewhere that the leadscrews on these mills is actually a metric approximation of inches, and the inch dials will show some error, but I'll figure out -- will also check my DTI, out of curiosity.

"Chinese universal" leadscrew definately could be one possible culprit. I have one in lathe....dial has metric and imperial markings (that are not really that accurate) and later I found out that the leadscrew on the cross slide is not really metric, nor really imperial. I have been miking a diameter a lot and usually mount DTI onto cross slide to positively keep track on last few mm of diameter when I try make last few passes to hit the target and keep DOC fairly constant.

Offline vtsteam

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Re: DIY bluetooth DRO for my mill
« Reply #26 on: May 08, 2022, 05:52:40 PM »
I just happened to find that there are TouchDRO videos for the various functions of the bluetooth DRO software. This one illustrates drilling multiple holes in a sequence, but the really cool thing about it is the graphical interface showing the layout of the holes, which can give a preview and zoom and move with your machining. This is a big step up from just getting the numbers for locations.  :coffee:

There are a number of other videos in this series.

I love it when a Plan B comes together!
Steve
https://www.youtube.com/watch?v=4sDubB0-REg

Offline tom osselton

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Re: DIY bluetooth DRO for my mill
« Reply #27 on: May 08, 2022, 06:45:19 PM »
That is a nice feature.

Offline vtsteam

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Re: DIY bluetooth DRO for my mill
« Reply #28 on: May 08, 2022, 06:53:22 PM »
I don't know if I mentioned it before, but you can also build one of these very simply from an Arduino Uno ($10 for a clone) and an HC-05 bluetooth adapter, and a few resistors. See here:

https://www.yuriystoys.com/2012/09/arduino-bluetooth-module-wireless-dro.html
https://www.yuriystoys.com/2013/07/arduino-dro-build-instructions.html

Firmware:
http://rysium.com/projects/196-arduino-dro

TouchDRO software for phones or tablets is an Android app available from the play store.

Of course if you want one fully wired, that's available on the TouchDro website. That one does all sorts of scales.
« Last Edit: May 08, 2022, 07:22:20 PM by vtsteam »
I love it when a Plan B comes together!
Steve
https://www.youtube.com/watch?v=4sDubB0-REg