Jump to content
 

Help needed with a digital caliper


burgundy

Recommended Posts

My apologies if this is in the wrong area, but it seemed the most likely forum in which to ask for advice.

I have a digital caliper which has started generating erratic readings. post-9472-0-70495400-1320180859_thumb.jpg

post-9472-0-39740900-1320180904_thumb.jpg

I suspect that this may be because the battery is running out. The label on the back indicates that it takes a SR44 battery, which implies that it is a replaceable item. However, it is not obvious how to remove the battery or which bit of the caliper opens to allow access. Since the caliper is designed to read to 0.1mm accuracy, I am a bit reluctant to simply apply brute force. Can anyone advise, please, how I should open it up?

Many thanks

Eric

Link to post
Share on other sites

Guest baldrick25

Mine, which is of a similar , but different design, the battery cover is located above the word "zero" (in photo 1) and is serrated ( stripes in the plastic) . To open, slide slide the cover towards the CE in photograph 1. It clicks first , then slides, and inside is not one but two batteries, but mine is the 12inch version. Hope that helps.

 

Edit. I have just imported your pic into a graphics package and brightened it, the battery cover is there and is the serrated arrow head in the moulding above the 'zero' in picture 1.

Link to post
Share on other sites

Remember before you use it to zero the caliper and hold it up to the light with the jaws closed. There should be no gap between the jaws. If there is simply clean the face of the jaws with a cloth or tissue. I used to clean mine by gripping my shirt cuff in the jaws and slide the caliper off the cuff while maintaining light pressure. Check again for a gap between the jaws. If it is still there do a check for a burr at the tip of the jaws. Open the jaws and test for a burr by using your fingernail. Usually this will only be on the tip of one jaw. Very carefully grip a piece of fine wet and dry paper with the abrasive side on the burr. Close the jaws and pull the paper out of the jaws whilst maintaining pressure. This should remove the burr. Clean the jaws and do the light/gap check, which should now be OK. It takes longer to explain than to perform, but you will get used to looking after your caliper to avoid these little burrs. Please do not be tempted to to remove burrs with a file. With a little care your tools should last a lifetime.

Link to post
Share on other sites

Thanks to Halfwit and Ohmisterporter for their suggestions and I have checked for any dirt - using both kitchen towel and shirt cuff!

However, the problem was solved by the purchase of a new battery and it is all working perfectly.

Just for the sake of clarity, when I said "erratic readings" it was not a case of the gauge producing an inaccurate figure. The gauge was showing a sequence of numbers which kept changing so that it did not actually register any usable reading.

However, problem now solved and thanks to all.

Best wishes

Eric

Link to post
Share on other sites

  • RMweb Premium

This website may be of interest to users of digital vernier calipers, with respect to battery life and battery part numbers:

 

http://www.davehylan...iper-Batteries/

 

HTH

 

Brian

 

Thanks for that, looks almost as much 'fun' as finding a suitable battery for old film cameras!

 

Edit: At least the measurement accuracy of the Chinese calipers looks reasonable, more accurate than my modelling anyway.

Link to post
Share on other sites

The battery thing is interesting as i've normally just bought using the "CR2032" descriptor.

 

I had to buy a new one of these cheap calipers in the past when the numbers started showing up at random, Although the battery had been replaced it seemed any pressure on the circuit board was setting it off at random. The new one has been fine for a few years now though and £8 wasn't too big an issue.

Link to post
Share on other sites

Guest baldrick25

The battery thing is interesting as i've normally just bought using the "CR2032" descriptor.

 

I had to buy a new one of these cheap calipers in the past when the numbers started showing up at random, Although the battery had been replaced it seemed any pressure on the circuit board was setting it off at random. The new one has been fine for a few years now though and £8 wasn't too big an issue.

The trick there is to switch on the caliper so the display is working, remove the battery or batteries, whilst still switched on, or after removing the batteries , short circuit the pairs of connectors inside the caliper for at least a minute or more. leave without batteries in , for half an hour ( overnight is better ) , remove the short circuit from where the batteries fit , replace batteries and power up/ reset / zero the unit. Its often the little CMOS processor that gets corrupted as the battery voltage falls.

Link to post
Share on other sites

  • RMweb Premium

 

Thanks for that, looks almost as much 'fun' as finding a suitable battery for old film cameras!

 

 

 

 

I was in the bank one day, depositing some coins from my club. The teller had trouble with the battery powered scales giving odd (inconsistent & impossible) results - easily proven of course, by taking the coins out of the bag & counting them.

She mentioned that she will have send them back for re-calibration, I suggested that they merely replaced the battery.

 

Kevin Martin

Link to post
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...