Over the last week have I had a quick course in finding out about grinding techniques and finishes, the hard way
A job I have recently finished, some disks 20mm thick, 400 mm in diameter with two big lifting eyes welded on have been specified by the company to be ground flat and to a 8 micron finish.
In the last week I have found out that Lumsden grinders can't get to an 8 micron finish and the only grinders capable of getting this finish can only do these plates 1 at a time and no one will quote me times / prices other than hint they will be expensive due to the welded on lugs not allowing them to be clamped down without a lot of messing. I have literally spent two days pulling hens teeth.
Well today on another matter of collecting some R8 tooling I called into Arc Euro Trade in Leicester. Whist I was there Katon showed me some lines that were coming in. One item that caught my eye was a swivel table about 6" x 8". Nothing new they have been around for ages. The base bolts to the bed and the table swivels on a semi circular saddle with a scale on the end.
I have one of these I bought a couple of years ago from Chronos, same design. The table top has been planed and is a matt gray colour, marking on the side are not quite even and obvious Chinese type numerals, still satisfactory and does the job.
The one I saw at Arc today is full ground, even on the ends. Numerals even precise and clear. The best bit is the finish. Without a comparison gauge this has got to be finished to 8 micron or possibly even better. Ten minutes with a tin of brasso and you would have been able to see your face in it and I mean that.
It is obvious that these rather mundane items are being produced on grinders the like of which we haven't seen here but more importantly we can't afford.
-- Regards,
John Stevenson Nottingham, England.
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