DRO for mini lathe (part 2)

[@winandd8649]

You're the second person on youtube having troubles with this DRO / scales combination. Another video about these bad scales prevented me from buying them. I'm glad I bought a regular big screen DRO. Z axis uses glass scale, X axis uses a magnetic scale (had to because of size), and it's working reliably. Thank you for the warning to other people, because it's better to spend a bit more money on the first buy, than having to spend money two times

[@isidoromaich7226]

Looks awesome! I saw many people giving 5 stars on Aliexpress as soon on arrival without trying first the product. Thanks to honest tests and reviews from people like you is possible to be aware from which product is ok and what is a nono

[@parentpatrick780]

Hello and thank you for this video. On aliexpress, it is indicated that these magnetic rulers are intended for working with wood and stone. Don't steel shavings stick to the magnetic strip?

[@zhadlun]

There is rubber cleaners connected to sensors. It's common for metal working machines to use magnetic scales.

[@njkotzur]

Thanks for the video. I have two thoughts on why the mini DRO was inaccurate. The sensors work by creating an electromagnetic field at the reading surface and then detecting changes in this field due to the magnetic zones in the strip. My best guess about the inaccuracy is this. The aluminium , while not magnetic, is still a conductor and will distort the sensor's electromagnetic field. Because the aluminium is close to the sensor on three sides, i think this would be a worst-case scenario for distorting the field. Also possible is that the magnetic strip has manufacturing faults. Note that replacing the electronics and sensors won't fix either of these faults. I bought one of these mini DRO devices and mine works fine on the bench. I think your original mounting arrangement was good. I am going to copy your design but use pvc channel instead of aluminium.

[@zhadlun]

I made so much tests there, and only one think is a firmware itself. I was even change sensor on a board, and still the same channel was wrong on a same places of magnetic strip. So a problem exactly with a board itself or firmware on a board.

[@pulidoggy]

@zhadlun Hi Volodymyr, I'm an absolute beginner in turning, so my question is possibly naive... I'm interested in implementing a DRO for my small lathe, so I was watching your interesting video, but some doubts arised. About the positioning of the Z axis sensor, I understand this is the standard choice, but this leaves undetected all movements made with the compound cross-slide. And yes, I understand that a diagonal arrangement of the cross slide implies a combination of X and Z travel, and this could be tricky to show (and to read) But in my case, I don't do tapers (not yet...) and thus I keep the cross slide exactly aligned to the Z direction, and I'm using it for small Z movements since I find it more precise and smooth compared to the Z handweel, but this would obviously defeat the Z readout, thus it looks like I'll have to refrain from using the cross slide in DRO mode... So, is there a possible workaround for this, like using a third sensor for the cross slide and a 3-axis DRO? Could it make sense, or am I overlooking / overcomplicating something? ☺ Thank you! Roberto

[@zhadlun]

Yes it's possible to use 3 axis DRO. And even some displays could combine values from both sensors and show them as 1. And if you have a place for 3rd sensor, go for it.

[@bobweiram6321]

You shouldn't pay return shipping for a defective product. That's nuts! Is the gauge on the lathe off due to backlash?

[@zhadlun]

That's all you need to know about aliexpress (( But sometimes there is no other options than to buy stuff there. The gauge is that because of screw geometry, it's the case for all small lathe of this days...

[@borisdesdorf7194]

Do you have a link please Nice video