Starrett 98/12 inches Vial replacement expert advice needed

[thorens]

the base will be send to Ewan to grind .
Peter

[jhovel]

Grind??? What do mean, 'grind'???

The base needs to be scraped - properly - to within a few micro inches or so and 40 points pre square inch bearing.....
If you just want a ground one, buy a Chinese one

[thorens]

Grind??? What do mean, 'grind'???

The base needs to be scraped - properly - to within a few micro inches or so and 40 points pre square inch bearing.....
If you just want a ground one, buy a Chinese one

Thanks for your comment.
I thought set it up on the surface grinder and clock it proberly will be just as good as it can get ? no ?
Peter

[jhovel]

It's probably just fine - but I think precision tools should have the 'right' finish and 'look'....

[cba_melbourne]

Thanks for your comment.
I thought set it up on the surface grinder and clock it proberly will be just as good as it can get ? no ?
Peter

The level is probably going to be used on ground surfaces? If so I see no advantage in scraping the level.

Also, I believe that standard Starrett model 98 "machinist" levels were not scraped from factory. The Starrett clone from Rabone that I have is not scraped either. It could be that the much more sensitive (and expensive) Starrett 199 "Master Precision" levels are/were scraped, I do not know?

[thorens]

The level is probably going to be used on ground surfaces? If so I see no advantage in scraping the level.

Also, I believe that standard Starrett model 98 "machinist" levels were not scraped from factory. The Starrett clone from Rabone that I have is not scraped either. It could be that the much more sensitive (and expensive) Starrett 199 "Master Precision" levels are/were scraped, I do not know?

yes it will be used for lathe set up so i would say it will be used in a grounded surface . please see the picture of the base of my 98 level condition . it have some rust and when i clean the rust it leave some pitting so i thought send it to surface grinder to re-ground the base is a good idea . i don't know about the 199 model so i have no comment.
regards
Peter

[azzrock]

I understand what joes saying but u think grinding would be a good start and maybe scraped at a later date.
aaron

[Stustoys]

If so I see no advantage in scraping the level.

Wouldnt that depend on the grinder? Both how the level is clamped and how good the grinder itself is?

Which brings me to my point.... how you going to hold it Ewan?

Stuart

[Ueee]

No need to worry about the grinder.....It will hold .001mm over that size with ease.

As for holding, without having the level in my hands it is a bit hard but am guessing that putting both ends in a vice would be the best, we shall see.

Ew

[Stustoys]

No need to worry about the grinder.....It will hold .001mm over that size with ease.

Says who?(or what?)
Now it may well grind parallel within 0.001mm but that's not flat*.

Stuart

*of course it might be that flat... but how would you know?

[Ueee]

Says the rock, my millimess and a holding meathod that does not stress the test piece at all.

Ew

[Techo1]

As this is not a high precision level there is no need for micron precision on the base. It really is not even suitable for setting up a lathe when trying to remove or introduce twist in the bed as the vial is calibrated to .005"/foot/division.

[thorens]

As this is not a high precision level there is no need for micron precision on the base. It really is not even suitable for setting up a lathe when trying to remove or introduce twist in the bed as the vial is calibrated to .005"/foot/division.

Thanks.
so what do you use those Starrett 98/12" level for ? you worry me now
regards
Peter

[PDW]

Thanks.
so what do you use those Starrett 98/12" level for ?

Rough carpentry. I should know, I've got a 6" Starrett.

PDW

[Bryan]

Thanks.
so what do you use those Starrett 98/12" level for ? you worry me now
regards
Peter

They're great for getting you within range of a finer level. 'Roughing in' if you like. The 98 series is described as a 'mechanic's level'. I think that word used to mean fitter/machinist. I guess they were considered ok for setting up run-of-the-mill machines doing ordinary work. Which probably means most of us here. The finer ones are needed for rebuilding work.