Poor mans lathe DRO's

**bobs409** · Mar 27, 2017, 07:09 PM

Just a shot of some cheap Harbor Freight digital calipers I adapted to my mini lathe. I will be adding similar to the tail stock and possibly even the compound slide. It's about the cheapest DRO you'll find and they are quite accurate! They repeat everytime too.

**DIYer** · Mar 28, 2017, 06:43 AM

Thanks bobs409! We've added your Lathe DRO to our Digital Readouts category,
as well as to your builder page: bobs409's Homemade Tools. Your receipt:

Lathe DRO by bobs409

tags: DRO

**C-Bag** · Mar 28, 2017, 08:22 AM

I likeee, sure would be nice some closer pic of the mounts as I am lazy!

Thanks for posting.

**Frank S** · Mar 28, 2017, 11:13 AM

I will agree that a digital caliper can be reasonably accurate. I've owned dozens of them over the years but none of them seem to last for very long at least not for me that is. I once owned an 18" Mitutoyo very pricey. Far too pricey for no longer than it lasted in my opinion
At least whit the HF ones they are inexpensive enough that one doesn't mind modifying them to fit the desired application I just wish that someone would come up with a way to hare wire any of them into the machine's power And I may have just thought of a way to do just that by removing the batteries and soldering ina pair of leads to connect to a DC converter with the correct output voltage

**C-Bag** · Mar 28, 2017, 12:44 PM

Originally Posted by Frank S

I will agree that a digital caliper can be reasonably accurate. I've owned dozens of them over the years but none of them seem to last for very long at least not for me that is. I once owned an 18" Mitutoyo very pricey. Far too pricey for no longer than it lasted in my opinion
At least whit the HF ones they are inexpensive enough that one doesn't mind modifying them to fit the desired application I just wish that someone would come up with a way to hare wire any of them into the machine's power And I may have just thought of a way to do just that by removing the batteries and soldering ina pair of leads to connect to a DC converter with the correct output voltage

Different calipers seem to work differently with battery life. I have an igaging DRO on the z axis on my mill drill that is basically the bar and the slide without the caliper jaws and it's 4yrs old now and still has the same lo buck button battery that came with it. Meanwhile I bought a digital 4" caliper from a well know supplier and even though I seldom use it, it eats batteries and is always dead every time I pick it up and with good expensive buttons even though it turns itself off like they all do. Igaging also has a USB port and a little charge port for some of its series of DRO's.

I personally like my dial calipers just fine and have had good luck with them.

So bobs409 how have your HF calipers been holding up battery wise? Do they have any ports like USB or charging?

**olderdan** · Mar 28, 2017, 12:53 PM

Originally Posted by bobs409

Just a shot of some cheap Harbor Freight digital calipers I adapted to my mini lathe. I will be adding similar to the tail stock and possibly even the compound slide. It's about the cheapest DRO you'll find and they are quite accurate! They repeat everytime too.

Nice work Bobs,
I also use this method for occasional use on the lathe saddle, in my case the calliper is not modified.
I mostly use it when coordinate drilling and it is mounted on the thread dial spigot, very useful and accurate.

**Woodgeezr** · Mar 28, 2017, 05:26 PM

digital calipers that use the LR44/A76 battery will last a lot longer if you use an SR44/357/303 battery. they are all the same size, but the LR44 is an alkaline battery. the SR44 is a silver oxide based battery. silver oxide will last for years. alkaline - months.

**C-Bag** · Mar 28, 2017, 05:56 PM

Thanks for the info. Just checked it and I was using the SR44 because that's what was in it originally and I'm not smart enough to know those crossover #'s, but I do now

still eats the SR's in no time. There's obviously something wrong with it so it's out of the lineup.

**Frank S** · Mar 28, 2017, 06:07 PM

Originally Posted by Woodgeezr

digital calipers that use the LR44/A76 battery will last a lot longer if you use an SR44/357/303 battery. they are all the same size, but the LR44 is an alkaline battery. the SR44 is a silver oxide based battery. silver oxide will last for years. alkaline - months.

Thanks I have 3 dead calipers now I will have to see if I can find a silver oxide replacement for them
I've had several over the years that would cease to function in minutes after replacing the batteries. My temperament is not such that affords me with rational thinking when I grab a DRO caliper expecting it to function properly and doesn't. If it fails to switch on that's fine I just figure the battery is dead but when it gives me erratic readings while I am using it due to a low battery or something else I usually fold it before thinking

**bobs409** · Mar 29, 2017, 12:21 PM

Originally Posted by C-Bag

I likeee, sure would be nice some closer pic of the mounts as I am lazy!

Thanks for posting.

Alrighty. Here's a few. I made U shaped bracket that clamps onto the cross slide at the back. One cap screw on the left side holds it in place. At the front side of the cross slide I added an attaching block. There was 2 existing holes there so I took advantage of those. The last one is actually one of two stop blocks I made for the ways. I used one of them to attach the end of the caliper and made a knurled knob to so no tools are needed to remove it.

Of course every machine will be different. Mine is a 7 X 16 Microlux.

Hope this helps.