Miniature DRO made from a digital tire tread depth guage

[Jwest7788]

Check it out! (Turn your speakers down, sorry youtube song to cover up the shop chatting)

 

[Mphenley]

I've seen numerous home-made DRO mods that use readily available digital calipers, but they have several drawbacks. Foremost among them is usually the auto-off feature that can't be disabled. They lose their setting when they turn off, making them only useful for a small time window of inactivity. Bit of a pain, really.

Also, they are somewhat limited in size, so while useful for most desktop size machines (at least on the cross slide and/or quill) they don't have the range needed for a larger machine like a 3-in-1's cross slide or even a desktop lathe's full bed length.

It appears most of the chinese DRO offerings use the same capacitive measurement, and you could take advantage of this and use a particular circuit to increase the length, but at some point your time is better spent making money to buy a full-scale DRO instead.

Ingenuity FTW, however!

 

[Jwest7788]

For sure. This little guy isn't going to fit all of my needs. But it's perfect for the type of project I've been working on lately!

Do you have a DRO solution in place?

 

[Mphenley]

Nope, but I've done some extensive reading. Because my machine has two large axes instead of just one, it increases the cost quite a bit. I'd been looking at making my own hybrid CNC conversion so I could use CNC operations, still have manual control, and then pull a feed from the electronics to make a DRO display. Might be a bit of a long project though.

 

[Jwest7788]

That's a slick method, Setup CNC, then extract a DRO. Smarter than the other way around actually.

 

[Mphenley]

Really depends how good you are with custom electronics and programming. And if you take your DRO from a rotary encoder on the screws, you'll introduce some backlash error in the displays, where a straight DRO setup won't have that issue. Might do a hybrid of the two, use a typical linear capacitive encoder to tell the CNC system how much backlash there is, and display the readout after that.

 

[kylemp]

In case you haven't seen this.. http://www.yuriystoys.com/p/android-dro.html
You can get the cheap igauging "scales" from busy bee and adapt them, or just use those as a DRO.. this is just a nicer interface.

 

[Jwest7788]

Thanks for passing that along. Pretty slick indeed.

I'll have to add the Igaging to the shopping list. Haha

 

[Rick Runciman]

Tons of great ideas. I saw some dro's that mounted on the machine dials and probably worked from a tachometer. I don't use them,, I apprenticed years ago, and learned old school,, good to go with knobs and dials.

 

[Tom O]

you know the shopping list gets bigger not smaller!

 

[Rick Runciman]

The trick is not to break your bank, learn to work with less.

 

[Jwest7788]

The trick is not to break your bank, learn to work with less.

This is 100% the reason I am using a tire tread depth gauge as a DRO. lol

 

[Rick Runciman]

I'm using a 25 year old tekloc dial indicator that's pretty beat up. I put a magnetic back on it, and just stick it to the ways. Mitutoyo made a digital indicator about 17 years ago, but it didn't do too well, as it's easier to see an analog dial approaching it's zero coordinate. And you have a good grasp on the essence of machining, tooling and accessories cost a small fortune. He who does the most, with less, has the biggest bank account. For my small mill, maybe a cheap Chinese digital vernier would make a good dro.