Stressing over numbers

Objectively the combination of inexpensive DRO systems, affordable inserts and at least reasonably accurate dials on affordable new and most decent used machines are game changers for Model Engineering. But the way we look at things and standard newbie teachings haven't caught up.

Back in the day Model Engineering was very much a craft. You made things to fit with caliper and rule based measurements. In post war years maybe a vernier or micrometer would have been affordable. If really posh perhaps a Unique "dial gauge" too. Which was about the state of play in the mid 1970's when I caught the machine bug. But I got lucky with a shop clearance sale for a dial gauge.

Hard saving needed if you wanted a machine with reliable dials but used Myfords, Boxfords, SouthBends et al could be found. Even more hard saving to get a new machine. I recall my then boss mimbling hard over a new Boxford ME 10 or a new Portass, cheaper but no dials, to replace his Zyto. He got the ME10, I suspect the quotation from Portass was one of the last they ever issued.

Over the years affordability, availability and capability of machines and tools have steadily increased and experienced folk work the tool-room way relying on accurate machines and accurate measuring equipment. I guess I'm now rather better equipped than the local section workshop was when I worked at RARDE / DERA / DRA / Qinetiq. Maybe not toolroom but high precision expected. 45 years in I still haven't the experience to use what I have to its full abilities.

When you have a good DRO set-up and reliable dials the approach is different. Much closer to the old production line operator working to stops on the machine set by the tool setter. Except you are both tool setter and operator. The basic modern way is to take a cleanup cut, set DRO to zero, measure, work out how much there is to come off, reset DRO so it will read zero when the job is to size and have at it with a check measurement before the last cut on the first part. It should come out right. If not adjust the final zero position and all the rest will be right. If they are not then more practice needed. Learn to love the many memory registers on the DRO.

I don't have a DRO on either lathes so I set the dials to be zero at finish size. Same thing, different equipment. If I did have a DRO I'd still set the dials too as I find it much easier to control cuts by handle angle rotation rather than watching flicking numbers. My view is dogtal is great for getting start and end points, not so good running in between.

Rant mode on. Why can't I get a DRO that makes it easy to connect a switch integrated into a stop so the machine turns off auto feed or threading when the DRO hits zero!

Clive

Gents thank you very much for sharing your knowledge and thoughts. I feel alot more educated and happier now with my machining.

Ive been told many a time that "I dont just scratch my a**e hole, I tear a new one" and I suppose its true. Because I never know when to stop. I'm very rarely satisfied with anything I do I always pick faults in it.

Thank you all again

Regards and stay safe

Mike

Ok, thanks. Seems a bit rude to me, even if I agree with the underlying point. But what do I know!

Andrew