A video showing how simple it is zero a dial caliper after an "oops" moment, no, not that sort ofone!
|chris stephens||25/08/2018 14:41:28|
|1045 forum posts|
As promised on another thread here is the video, I have put the link here as a new thread in case the other thread is not followed by all.
I have come across calipers marked Mitutoyo that do not have the feature, whether they are cheap knock-offs or older versions I cannot say.
|Clive Foster||25/08/2018 15:30:53|
|2157 forum posts|
That's the older style of Mitutoyo dial caliper with single gear movement. No springs or anti-backlash gears but generally works well. Weakness is that the gear can jump a tooth on the rack which is why a re-setting tool is provided.
Later versions have a more complex movement, can't be fixed in this manner and (allegedly) don't have problems.
Fairly sure that skinny hand and Made in Japan on the dial mean its an old type movement. Had one with a thick hand and Made in Brazil on the dial which certainly was the later movement. Swopped it out for older version in equivalent (new, only unpacked) condition so I had Imperial and Metric ones in same style. I personally don't care for the new movement and dial style.
|Martin Johnson 1||25/08/2018 17:30:34|
|129 forum posts|
The video refers to the later style. The older style Mitutoyo (1974 I think mine is) was supplied with a little tool in thin copper beryllium sheet. There is a round end to grip and a thin bit which you push along the rack from the left hand side of the dial, when the calipers are open a bit. You are then basically hooking under the pinion wheel to lift it off the rack, move along one tooth and drop the pinion back into engagement. It is a fiddly operation and rather hit and miss, but you can get there after a few tries.
A lovely tool, though and worth getting it to work. You need some decent eyesight to discern parts of thou's though!
|Clive Foster||25/08/2018 19:14:27|
|2157 forum posts|
You live and learn. Looks like there are at least three types of movement then. The Made in Brazil 8" one I didn't like was new in 2012 - 2014 or thereabouts if memory serves me right. No tool in the box no details on resetting. Very chunky hand and graduations along with heavy action with poor feel. Wanted to reject it but Mitutoyo and supplier didn't want to know. Sold it for around quarter new price, buyer happy.
The Made in Japan that replaced it would have been of similar vintage. I'm pretty sure you could still find both Made in Japan and Made in Brazil styles on sale then so must have been close to the model changeover period.
Just been out to look at mine. Shoulda done that in the first place rather than trusted memory 'cos tuns out I have one Made in Japan and one Made in Brazil with same movement having much nicer action than the one I rejected. Thought I'd ended up with two Japanese ones. Same adjuster tool in box of similar shape to the one in the video with the same square loop to hold it with but made from flat copper beryllium rather than round wire. Slot under the dial opposite the rack for the tool to go in so no need to remove the bezel lock clip and screw. I imagine the pinion is spring loaded against the rack so the tool can lift it clear. Interestingly the ranks are on opposite sides of the bar. Metric, Brazilian, one on top i.e. same side as the internal jaws and imperial, Japanese one, on bottom.
|Michael Gilligan||25/08/2018 19:17:07|
15484 forum posts
Visible on the leaflet, in the picture on the other thread: **LINK**
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