I can't exactly say what parts are, sorry.
Stainless steel high temperature resistant.
Tubular and flat shapes with several grooves. Outside and inside threads. Parts must perfectly match each others.
Tubulares around 120mm long and squares around 150*200*45.
Thank you.
We / I have very similar application requirements (superficially).
Without knowing more about your form tolerances and how one set of surfaces may have to relate to another set orthogonally or on weird angles it's hard to give 'Accurate" advice. So in sense more randomly applied advice is given (no change there lol).
First thoughts that comes to mind are...
1. Cycle time and automation-ish / multitasking ?
i.e. ---> How many of these in a year do you have to make and what kinds of efficiencies are required to make what you are producing viable from a business point of view ?
2. Are vertical mills really the answer ? [ what a bout B axis mill turn machine ? (sim 5 axis capable ?)].
Something like a 5 axis (B axis) mill turn machine can be very accurate . Typically for turned surfaces a turning operation on a good turning center can be sub-micron roundness and form tolerances of the order of 5 micron or less.
Also where you have
circular or tapered features that have to be
orthogonal to referenced accurate
longitudinal milled features;, depending on skill , fixturing and general process awareness high part accuracies can be achieved in an efficient manner. Same / similar for large bore threaded features and precision threads that may be part of a more complex mill-turn type geometry. Those being good reasons for a 5 axis B axis mill turn machine.
IMO form tolerance of turned features is much higher than that of vertical mills that aim to 'Do" turning operations for the part sizes you are talking about here.
3. Different types of grinding (to finish and fit to size) come to mind (for harder materials) … Particular jig grinding... With a Moore (tool company) level spin table and precision sine plate that external radii of interrupted cuts and even external short tapers can be brought to high tolerances.
4. Hand work / fixes / artful design and builds and various hacks... WHY 'cuz not everything can be delivered by CNC milling or turning. For example with air spindle can you can execute some grinding operations on a Hermle but "They" don't recommend it as it will bugger the machine (ultimately)… Other machines can be hacked into bastard jig grinders. There may be other techniques that employ hand lapping of certain surface or various kinds of lapping jigs that could be built to make your high tolerance components fit ----> For example if you are making precision assemblies that resemble bearings of one kind or another that both have linear and rotational elements.
5. In other words Kern or Yasda may not be the answer, just a different process or set of processes, depends on application + actual functional surfaces and tolerences and how they reference each other. Set up time and number of precision set ups and actual cycle time are a major consideration IMO and hence a B axis mill turn machine can be very efficient and accurate. Otherwise a part has to walk around the shop between 5 machines and numerous set ups... Lot of fiddly set ups that require a steady hand and Ritalin (they don't go together very well lol), and plenty of opportunities to screw up OR you design elements into your parts for precision fixturing.
With some B axis mill-turn machines in cycle gauging can be applied (using 3d probes like from Renishaw to map out the topography of a gear or fan blade to plan final cuts) … That's a whole different set of rock throwing and set of arguments.
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@ricardo_gt can you give any idea of form tolerances ? And what needs to relate to what and to what degree (especially angular tolerances.).