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Optical comparator

ARB

Titanium
Joined
Dec 7, 2002
Location
Granville,NY,USA
Now that I am on the far side of 45 my eyesight is taking a nose dive.
Many many moons ago I used an Optical Comparator when working for GE.
I find myself wishing I had one on a regular basis nowadays. Mostly for measuring small details or checking angles and such. The occasional radius.

After watching a vid from Suburban with them using the quadra check DRO I can say that I would like one of those. If for nothing else the cool factor.

I'm looking for some does and don'ts for buying a used machine.
What brands to stay away from and what things to look at.

I'm thinking a 14" unit would do what I need.

Anyone have a nice one they want a new home for?

Thanks
Adam
 
Now that I am on the far side of 45 my eyesight is taking a nose dive.
Thanks
Adam

Off track but maybe this will cheer you up. About 3 or 4 years ago what I saw through my glasses (use them when driving and watching TV) started to get a wee bit blurry. Came to the conclusion I needed new glasses and went to my optician. Long story short. My vision is as good as perfect now and I no longer need glasses. Surprised the hell out of my optician :)

Forgot to add - I'm 74.
 
74 ? I think you are older than me… Where is my calculator? Darn out of batteries,


Jones & lamsom, XLo and Starrett were good names .. Likely most are good. .I always like a floating table that could simply push off one end stop where there might be a micrometer dial so one could come out on a jo block stack and also turn the micrometer dial to see the off gauge amount.
Screen might be a choice factor also, I liked a screen with radius and basic angles.
We have a few local guys who pick then up at auction and rehab them.
 
The Quadra Chek is great! With some care, even short segments of radii can be measured by checking 3 points. Lots of canned commands to check common features. Mitutoyo used to run package specials on comparators with these units.
 
Try to buy one that has enough lens so the image you view is rightside up, not reversed and upside down. Some to keep the optic cost down don't do this, but it can be a pain on a complex part. You can get used to it but it offers a challenge.
 
I have a tumico 14". I have not used it much but plan to start because i am in your same boat. I had an idea- i bought a celestron usb microscope. These are qbout the size of a toilet paper roll. I think it would be real handy to pair the usb microscope with the optical comparator. The microscope has a cross hair that can be turned on and off.
 
A 14 is the universal size. For sure 30's are nicer but take up a lot of floor space. Hard to beat a 30 J&L with power lens change.
I'd stay away form anything under a 14 unless you have a special application.
Some different lenses are nice to have and expensive to buy later. Sometimes you need a big view, other times you need tight.
Good surface illumination is very important to some people, make it more like a microscope .Much can not be seen from the back light alone. Does not work well at 50-100x.
Stage centers if you do such things
Any DRO is nice, fancy ones do 3 point rad sizes but cost a lot. Auto edge detect is questionable IMO.
Mirror condition can be a yes/no. Clean these with paper towel and glass cleaner a few times and they are junk and big bucks to replace. Stage ways condition also important and expensive to fix.
A nice smooth protractor ring counts, screen with makings you like but you can print overlays on a ink-jet.
Most people like a horizontal better than a vertical.
Once your eyes start to go you will still need reading glasses when using one. I wear +1.0 around the shop but have +2.0 sitting on top of the comparator for when I need to get down there and it makes a big difference.
I know some that use 20-32x in the machine but have a big magnifying glass on a swivel arm mounted out front to look at the image.
I've seen old Covels at $200 that were golden, old J&Ls at $7000 that were junk.

I consider this machine a must have for any shop, right after you buy a six inch scale and before your digital mics.
I'm sure this all above helps....not.
 
Thanks for the replies guys.
Just the kind of info I was looking for.

Back in the day at GE I used a 30" J&L most of the time. I don't have the room for one.

I like the idea of the USB microscope.
 
....

I like the idea of the USB microscope.
If you once had a 30 you will not like a USB microscope. Useful guys and I have 6 but not the same animals.
If you do get one make sure it is USB3.0 or higher and you want super high pixel count.
A whole series of added problems here with camera sensor, resolution, flat optics and frame rates.
 
Carbide Bob is right about cleaning the mirror. I used to work for American Optical and we were cautioned about cleaning anything like this as it's (if applicable....) a First-Surface mirror. It's takes very little pressure to rub streaks in the mirror and diminish or ruin it. I will say that for almost all microscope lenses we used Sparkle glass cleaner without ill effect. That was the 70's and they're using coated optics now, this may suffer detrimental effect if using Sparkle glass cleaner. Always check with the factory before fooling with expensive optic components.
 
Wrong cleaning could wash off he ink lines or make then soft so soon getting thin. Taking the out the glasses they could get broken so we tried to never touch and had a curtain to cover when not in use to keep room air dust off..
 
Many optical comparators have stages on ball bearings. For moving the stage should be removed or separated from the lower stage to prevent the balls from brinneling the races.
 
I have a Starret HB400 with a Quadra Chek unit. I bought it off a PM member about 6 or 7 yrs ago. It's a little dirty and dusty now, but it was absolutely pristine when I got it. I don't use it a lot, but when I need it, it's the cat's meow. The Quadra Chek is slick. Measuring angles, multiple locations, and radii are a snap.
 








 
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