XARO: Putting Yesterday's Technology to Work

All discussion about lathes including but not limited to: South Bend, Hardinge, Logan, Monarch, Clausing and other HSM lathes, including imports

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Steggy
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Re: XARO: Putting Yesterday's Technology to Work

Post by Steggy »

Harold_V wrote: Mon Dec 14, 2020 2:57 amIn regards to the lathe's "exhaust"...Coolant and long travel indicators don't get along real well, so I used to slip a plastic bag over the indicator, one that completely covered the stem and the entire indicator body.
Hmm...I wonder if my wife would notice that the one gallon food storage bags are missing. :D
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Music isn’t at all difficult.  All you gotta do is play the right notes at the right time!  :D
pete
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Re: XARO: Putting Yesterday's Technology to Work

Post by pete »

Pre invention of electronic dro's all the jig boring and grinder manufacturer's were fighting a constant battle of lead / lag errors in there feed screws and nuts. Wear as the machine was used was also a factor when your shooting for 10ths or less. And extremely costly to heat treat, grind and then lap the screws and nuts to those levels of accuracy. You can still see there solution on some of those older machines. They changed the casting patterns to allow recesses to be cast into the cast iron parts that allowed high precision 1" travel indicators to be mounted dead in line with the table travels. Anything requiring over that 1" of travel they added half circular mounts at the indicators end and at the ground stop end the indicators tip would register against. They then produced to a much higher accuracy level what are basically what we have today for micrometer setting standards in increments of 1". Today those same jig boring / grinding rod sets can sometimes be found on Ebay if you know what to look for. Since almost no one today still use that method they usually sell for not very much. So your method has a fairly long and proven history BDD. At jig boring / grinding accuracy's, temperatures would have a measurable effect on a purely mechanical system. But most places would have had temperature controlled rooms for equipment like this to operate in.

Since those indicators were so expensive, those recesses usually had a pivoting mount for a glass cover that swung into place over the indicator with a rubber seal the door rested on and protected it. Some machines had that as well as a partial cut out in the casting to allow re-zeroing the indicators dial without moving those glass covers. And as already mentioned, indicators do not get along well with contamination. Any chips, fine swarf, coolant etc drastically reduces there life span and accuracy. Some metrolgy company's offer a light weight very flexible rubber bellow that snugly fits the indicator stem and it's plunger shaft. Mitutoyo is at least one who make these rubber bellows. But it's tough to find any supplier who carries them or I would have provided a link. But this shows an indicator with one. https://www.flexbar.com/products/waterp ... -indicator There designed for use in areas that may have high amounts of fluids or contamination exactly like a lathe might have.
earlgo
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Re: XARO: Putting Yesterday's Technology to Work

Post by earlgo »

BDD. Nice job I may steal your idea. I used a similar idea for the Z axis on my ancient mill.
Z ARO
Z ARO
Z ARO with warning
Z ARO with warning
But mine has a home made warning light because ..... well, replacement DIs are pricey.
By the way, SHARS tool sells a small DRO but the one I have lags behind a fast handle crank so one has to sneak up on things to maintain a good reading. Here is the link to the 6" model but there are different sizes available. https://www.shars.com/products/machiner ... inum-scale
--earlgo
Before you do anything, you must do something else first. - Washington's principle.
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Steggy
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Re: XARO: Putting Yesterday's Technology to Work

Post by Steggy »

earlgo wrote: Wed Dec 16, 2020 10:49 amBDD. Nice job I may steal your idea.
Wasn't my idea, though. I recall this sort of thing on lathes back when I was in high school (chronological hint: JFK was president when I was a senior). I'm always "borrowing" ideas from others. :D The impetus to make it came from my buddy Carl's lathe, which too has one.

In any case, glad you like it.
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Music isn’t at all difficult.  All you gotta do is play the right notes at the right time!  :D
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