it does take a delicate touch when measuring , have to use the end of thumbscrew when measuring it will click on the ratchet when it starts to get tight, don’t overtighten and all you are looking for is a sliding fit as you move it over the diameter. If it’s warm it will expand the diameter a small amount
Sometimes when you get a mic it will have the slip gauge in it to check it’s exactly 50.00mm which can be adjusted if it’s a bit out
Hopefully you can see Marjons figures and see them on the mic
Top scale is mm bottom scale is 0.5mm and one full rotation is 0.5mm
So if the edge is past the 0.5mm mark and you get a reading of 58.5 + 0.25 then you get the 58.75mm

If you set it to 63.49 it should fit on the mains while 63.47 should not fit without force but very small margins
 
it does take a delicate touch when measuring , have to use the end of thumbscrew when measuring it will click on the ratchet when it starts to get tight, don’t overtighten and all you are looking for is a sliding fit as you move it over the diameter. If it’s warm it will expand the diameter a small amount
Sometimes when you get a mic it will have the slip gauge in it to check it’s exactly 50.00mm which can be adjusted if it’s a bit out
Hopefully you can see Marjons figures and see them on the mic
Top scale is mm bottom scale is 0.5mm and one full rotation is 0.5mm
So if the edge is past the 0.5mm mark and you get a reading of 58.5 + 0.25 then you get the 58.75mm

If you set it to 63.49 it should fit on the mains while 63.47 should not fit without force but very small margins
Yes it does have the 50.00mm bar to set zero, think this is where I was going wrong, as when setting, then trying again most times it was out again which would be putting those final readings out to. Dont think I got it bang on, gonna have another try tomorrow , one thing I aint got is a delicate touch .
Did you do the Plasitigauge on yours ?
 
Nit used that, there is a procedure detailed in the manual to nip up main bearing caps and slacken one bolt off to measure gaps with feelers
 
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I read it as first pic 63.55
Second as 58.75

But I could be wrong, as the first 1 doesn’t make sense.

J
Trying again don't think this bloody micrometer is zeroing right. Can you make this reading out ?
 

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That might be 63.47 or 63.97 depends on how thimble matches with top mil mark or bottom half mil mark
What does it look like with the 50mm slip gauge inserted
 
Think this thing has to be faulty, can set it to zero as in first pic, but when go to use again to measure, it goes way out as second pic. Probably me doing something wrong, got my bloody head done in, then to top that ordered honing tool from amazon yesterday and they sent the wrong size so stuck again.
 

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Think this thing has to be faulty, can set it to zero as in first pic, but when go to use again to measure, it goes way out as second pic. Probably me doing something wrong, got my bloody head done in, then to top that ordered honing tool from amazon yesterday and they sent the wrong size so stuck again.
I can only look at that and say the “test piece” is wonky.

As I said earlier an accurate adjustable spanner is what I would use.
I personally don’t understand the use of a micrometer on a round journal, it is so hard to get it straight.
Did you use the little ratchet knob on the end to get the same pressure?

I am going to ask somebody here who may help with some pointers, may even point out my mistaken views.

@My Old Landy views on measuring stuff :). He might be away in his new caravan at the moment.

J
 
Thanks
I can only look at that and say the “test piece” is wonky.

As I said earlier an accurate adjustable spanner is what I would use.
I personally don’t understand the use of a micrometer on a round journal, it is so hard to get it straight.
Did you use the little ratchet knob on the end to get the same pressure?

I am going to ask somebody here who may help with some pointers, may even point out my mistaken views.

@My Old Landy views on measuring stuff :). He might be away in his new caravan at the moment.

J

I can only look at that and say the “test piece” is wonky.

As I said earlier an accurate adjustable spanner is what I would use.
I personally don’t understand the use of a micrometer on a round journal, it is so hard to get it straight.
Did you use the little ratchet knob on the end to get the same pressure?

I am going to ask somebody here who may help with some pointers, may even point out my mistaken views.

@My Old Landy views on measuring stuff :). He might be away in his new caravan at the moment.

J
Thanks. Trust me to get a faulty one. Yes used the ratchet kmob, think it is near enough though and within tolerances, not sure whether to take a gamble and just start building back together with the new bearings and rings or order some plastigauge too to try that for measure .
 
Trying again don't think this bloody micrometer is zeroing right. Can you make this reading out ?

I had another look and it is really deceiving.
As I can see the .5 mark and add the .47.
But I can only just see the .5 mark which really should be more showing.
So all I can really say is, your zero is out or I don’t know.

J
 
Plastigauge should tell you all you need to know.
If crank is std and shells say std then I would say it should be okay, but still needs checking, rest you can billy b**** your way through but crank is quite important.
 
I can only look at that and say the “test piece” is wonky.

As I said earlier an accurate adjustable spanner is what I would use.
I personally don’t understand the use of a micrometer on a round journal, it is so hard to get it straight.
Did you use the little ratchet knob on the end to get the same pressure?

I am going to ask somebody here who may help with some pointers, may even point out my mistaken views.

@My Old Landy views on measuring stuff :). He might be away in his new caravan at the moment.

J
I agree that it is technique and practice to get the reading correct.
If it won't hold tolerance on multiple readings (a different result each time) then I would say it is the user.
I (used to before getting sick) use a micrometer to measure round things on the lathe. With practice it is far better than a vernier.
For a larger unit hold the micrometer lightly in one hand and use the ratchet to get the same pressure.
The thing being measured should be held securely in a vice (or some other work holding device!).
Smaller mics are easy to use single handed.

I hope that helps @border ?
 

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