OK - so all the equipment was setup as shown in previous pictures. I also centered the cutter to the wheel centre and also leveled it square with the wheel blank.
The first issue arose as I started taking the second cut, I didn`t get a picture of it but the teeth seem bent and not straight! The first tooth to form looked more bent than the others so I don`t know why this happened! Perhaps my cutter is profiled at an angle and is therefore cutting wonky teeth? OR, and I could check this, is the cutters cutting area, i.e the cutter tooth, not at 90 deg to the arbor? I think this is most possible but will need to check it again tomorrow. This will explain why the teeth are at a little angle but not why the teeth look a little bent!
Well I know this wasn`t going to be used in my clock but I wanted to finish it to see what other problems arise:
Tooth form looks quite good so far!
Look at the first tooth and how bent it is ... obviously it is the furthest one away from the current cut in the next photo:
Then I finally got back to the start and that was just using 6 deg divisions on my RT, soon I`ll need to use a dividing plate and that should help a lot with spacing.
Next problem is the brass and how the cut is being taken. The brass is being bent rather than shaved or cut off. Notice how the teeth look a little convex ... not sure why this is happening BUT this is a scrap piece of brass and not the recommended CZ120 for clock wheels. Could this be the reason but look at the little bits that have been pushed forward and back instead of cut off. This is a major problem and needs sorting.
Notice the two teeth that a very close together at the top, this is where I made my final cut to come back around to the finish. I a dividing head will help here but I`m a little unsure why this happened as the error was not carried forward as I was simply cutting every 6 deg rather than adding up any errors...if that makes sense? Also the first tooth being bent doesn`t help the issue...
Then I had a brain wave, popped it back in the lathe to skim off these bits off the front of the teeth gap. What an idiot :bang: I caught the teeth tips with the cutting tool and stripped off the nice radius....[b]from now on in the pics the top of the tooth profile looks flat, that is my fault![/b]
Then it was time to strip off the wooden support. WOW the brass really had just been pushed back and not cut off! It was literally bent into the wood:
Then tidied it up a little more and now it looks like this:
Like I said, not a total failure, I learnt a lot but I have a lot of issues to sort out as this would be nowhere near good enough. I wonder if the brass type has a lot to do with it, maybe using the cz120 would cut rather than bend back? Have I used the cutter correctly feeding into the work on the Y-axis?
Some thinking time required.....
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