Thread: This is clever and cheap - digital readout for lathe - 25mm travel

Micro Digital Read Out

and digital gauges available here for $5.73 and free postage in Australia

LCD Digital Depth Gauge Tire Tyre Tread Brake 0 25 4mm Metric 0 1" NEW | eBay

I suppose there must be thread somewhere around where somebody has done the same thing with a 150mm digital caliper ?

Bill

Originally Posted by steamingbill

Micro Digital Read Out

and digital gauges available here for $5.73 and free postage in Australia

LCD Digital Depth Gauge Tire Tyre Tread Brake 0 25 4mm Metric 0 1" NEW | eBay

I suppose there must be thread somewhere around where somebody has done the same thing with a 150mm digital caliper ?

Bill

The one on your link is a particularly cheap model of depth gauge designed to measure tyre threads (and other soft objects). I do NOT recommend you buy this for something like a lathe carriage indicator. The feeler and the scale beam and the anvil are all made of a softish moulded plastic, it would melt if hit by a hot chip and if not it will wear quickly. They (the Chinese) also make better models of this digital depth gauge design, using metal parts (looks almost the same from afar, but its stainless and naturally costs a little more).

Been using a 200mm caliper as a carriage readout for ages now. (Edit: I'd seen the idea eslewhere.)
The mag base just slides along when it runs out of travel.
Cheap, crude, but very effective.

Originally Posted by steamingbill

Micro Digital Read Out

and digital gauges available here for $5.73 and free postage in Australia

LCD Digital Depth Gauge Tire Tyre Tread Brake 0 25 4mm Metric 0 1" NEW | eBay

I suppose there must be thread somewhere around where somebody has done the same thing with a 150mm digital caliper ?

Bill

Hi Bill, in a recent edition of MEW, they had how this was done. PM me if you would like a printed copy posted to you.
Sorry but dunno how to put it on here, maybe you could be so kind as to do it, if I sent it to you.
Kryn

Originally Posted by cba_melbourne

I do NOT recommend you buy this for something like a lathe carriage indicator. The feeler and the scale beam and the anvil are all made of a softish moulded plastic, it would melt if hit by a hot chip and if not it will wear quickly.

Yes - I once bought a 4" plastic digital caliper for those occasional jobs where nothing else will do and was disappointed because although it was listed as carbon fibre, I've yet to see where the fibre has been put. It is soft and the slide is sloppy and won't repeat to within 0.5mm. Waste of money.
Cavat emptor.

Michael

Originally Posted by Michael G

Yes - I once bought a 4" plastic digital caliper for those occasional jobs where nothing else will do and was disappointed because although it was listed as carbon fibre, I've yet to see where the fibre has been put. It is soft and the slide is sloppy and won't repeat to within 0.5mm. Waste of money.
Cavat emptor.

Michael

I did the project as in that web page.. I found the plastic version is accurate to .002" not any better . Mine will not repeat , it always goes back to a different value when you release the spring loaded probe . Mike

Originally Posted by KBs PensNmore

Hi Bill, in a recent edition of MEW, they had how this was done. PM me if you would like a printed copy posted to you.
Sorry but dunno how to put it on here, maybe you could be so kind as to do it, if I sent it to you.
Kryn

Article Attached,

Bill

Originally Posted by steamingbill

Article Attached,

Bill

I've been using a digital tyre depth gauge on my Myford tail stock for some time now.
I use a pair of magnets from an old 2.5" hard disk drive to secure it and have glued a couple of tiny magnets, also
from hard drives, onto the end of the stylus. I made a perspex/plexiglass collar that fits around the tail stock piston
with a small piece of 1/4" steel rod glued in to a hole so that the depth gauge stylus can grab onto it.
The only other things that I did was to reduce the tension on the guide spring to allow smooth movement of the stylus
and wiped the spring surface with an oily finger.

I'll take some photos and post them.

Baron.

Originally Posted by BaronJ

I've been using a digital tyre depth gauge on my Myford tail stock for some time now.
I use a pair of magnets from an old 2.5" hard disk drive to secure it and have glued a couple of tiny magnets, also
from hard drives, onto the end of the stylus. I made a perspex/plexiglass collar that fits around the tail stock piston
with a small piece of 1/4" steel rod glued in to a hole so that the depth gauge stylus can grab onto it.
The only other things that I did was to reduce the tension on the guide spring to allow smooth movement of the stylus
and wiped the spring surface with an oily finger.

I'll take some photos and post them.

Baron.

As Promised.

On the page linked to by Steamingbill Micro Digital Read Out is the following

both.jpg

The DRO is a 3 volt unit and has a noticeably faster refresh rate than the 1.5 volt caliper seen above. Lag is minimal.

Can anybody make a comment on this. Why would a tyre gauge have a faster refresh rate or is this just coincidence?

I would like to make a DRO of this type for my tailstock but 14mm or 18mm is way too short. I would prefer to use a 150mm caliper as per the pic above.

Dean

Originally Posted by Oldneweng

On the page linked to by Steamingbill Micro Digital Read Out is the following



Can anybody make a comment on this. Why would a tyre gauge have a faster refresh rate or is this just coincidence?

I would like to make a DRO of this type for my tailstock but 14mm or 18mm is way too short. I would prefer to use a 150mm caliper as per the pic above.

Dean

The tread depth gauge I have will easily do 2" any more and the slide tends to risk pulling out of the gauge. I don't seem to have to drill holes deeper than this
gauge can handle. As far as refresh rate is concerned, I can't see any difference between this and my expensive digital vernier. Nor can I see any difference
between the cheap one that I used for my hight gauge.

As a bonus I also use this on my "Fobco Star" drill. The magnets neatly stick to the head and the stylus magnet sticks onto the depth column. But again I
have not found the need to drill deep holes.

Originally Posted by Oldneweng

On the page linked to by Steamingbill Micro Digital Read Out is the following



Can anybody make a comment on this. Why would a tyre gauge have a faster refresh rate or is this just coincidence?

I would like to make a DRO of this type for my tailstock but 14mm or 18mm is way too short. I would prefer to use a 150mm caliper as per the pic above.

Dean

Because the new type calipers with circuit boards that use the 3V lithium battery instead of the silver cell are a 15 years newer design.

The old ones were clones from the Swiss Sylvac, which in the late 90's made the bad mistake to manufacture their scale boards in China. They did steal the circuit as well as the patent to the capacitive caliper. Since then, Sylvac keeps production in Switzerland.

I bought a cheap ($12.69) 150mm digital caliper from EBay and it arrived today. I bought it for a particular reason and if that did not work then I would use it on the mill quill or lathe tailstock. The quality of this caliper is rather suspect. The main shaft edges and the inside of the jaws are smooth. All the rest of the edges are rough including the internal jaws measuring face. It does not slide as smooth as I am used to. Luckily this does not concern me.

I have a 200mm digital caliper that I have had for many years. It stopped working earlier this year. I threw it in the scrap bin but then took it out again. I was looking at the price of these recently and at the time they were not very cheap and not very plentiful. I unscrewed the back of the new caliper and managed to fit it to the old one with just a little trim on the edge by the external jaw because it was a bit wider. It worked perfectly. The only problem is that this digital head will not read to 200mm. It will only go to 199.99mm then goes back to zero! Measures to 8.15 inches tho.

I am happy with the result and now I am going to get another one for the mill/lathe but I hope to get one that is finished a bit better.

Dean