After finishing off with the 400 and being back to a pristine blank I started with the new 600 and everything went well until the first was off where I found a small skid mark(no giggles please) near the edge.not 100% sure how it happened as I had thoroughly cleaned the tile and mirror beforehand but there it was.
the scratch isn't very deep and doesn't really catch when you run a nail(finger) across the blank so I went and carried on for 1 1/2 half hour with the 600 to see if it would start coming out.Unfortunately the scratch didn't seem to lessen at all so back to 400 grit and after about 1 1/2 hours the blank is back to a great starting point.This time ive learned a few things with finer grit.irstly don't just wet the blank when starting off, also wet the tile tool too as this gets rid of most of the initial sticktion with finer grits.secondly on the first wet from a clean mirror I alwals sprinkly the grit onto the blank and spread it out with my hand for even coverage and I think this will really help avoid edge scratches with the 600 as I think a lot are caused applying and removing the tile tool.I don't remove the tool inbetween wets I just add more grit and keep going.This lessens the tile removal times from once every few minutes to once every half an hour with the way I do it.I then turn the blank half a turn,clean it off and inspect my progress then start again for another half an hour.hopefullythis technique will work as with the near 2 hours of 600 last time I only picked up a scratch at the very beginning and no others after using the new technique.
This afternoon I will thoroughly clean the tile tool, the blank,change the carpet on the grinding table and I even remove old grits to the floor and change clothes to avoid contamination.This will be really important when I come to polishing!!
On a non asto related note I have just bought my first bike in about 10 years as im going to be doing a job that's about 2.5 miles away from my house.
Its the first non mountain bike ive had since I was about 12 so its amazing how much lighter and quicker it picks up speed and also how bumpy those 700cx28 tyres are!!its not a mega expensive one but I looked at a few bikes and the boardman ones semed well specced for the price and I love the look of the thing.first ride out the other was 4 miles and I was averaging 16mph and topped 20mph a few times on the flat.I wasn't hammering it but making a good pace to me but my normal taking it steady average today was 12.6mph.luckily round here its pretty flat and has good cycle lanes so its perfect for bikes.Another job im after is 4 miles away so 8 miles a day will be a nice way of keeping fit and saving wear and tear on the car and if its really bad weather I have the car to fall back on anyway as I don't fancy 700c tyres in the rain.
hopefully another update midweek
one thing to note,now im living on the southcoast rather than west yorks I can see Sagittarius from my bedroom window.It never rose high enough to see from west yorks so when my scope is ready next year is going to be a new beginning with many further south objects in my reach.
clear skies Rich