Andrew,
A bit of advice?
What you buy today may not end up all that useful later on. If you have full intensions of doing machining as a hobby long term, Then it's a real good idea to preplan for that. Most people end up after a certain ammount of time adding DROs to their equipment. If you buy a decent accurate DRO, You'll want tooling that's repetable when doing parts. Anything you can add to ensure that repetabilty is a good idea. I'd buy the wedge system and Phase 2 for the minimum quality. Maybe it's a fairly unknown technique with DROs and hobby machining? But the ability to index your tooling projection so that each tool has exactly the same zero depth is really useful. Simplified? All tools and quick change tool holders would machine a shaft to the exact or as close as possible to the same diameter according to the same DRO readings. That's certainly not possible for every lathe tool. But when it is, It's far faster to set up what tooling you can that's pre set to a zero condition, For as and when your building multiple parts to the same dimensions. Your DRO would have to be fairly high quality and repetable accuracy to use that technique. But a decent accurate two axis lathe DRO really isn't all that expensive. Just one more opinion and your thoughts may vary.
Obviously presetting your tools can be done with normal accurate lathe dials and a good QCTP system too. Real high end DROs like Newalls come with a tool numbering system. This saves pre setting your tools, But the projection still needs to be measured and verified under cutting conditions then minor adjustments get made till the tool agrees with the DRO.
Pete
