Puma P240 CNC Machine: How to Judge a Shop Running One
A 2002 Puma P240 CNC machine still turns plenty of work, but only inside a narrow window. This guide is for engineers and buyers who find a shop quoting on this lathe and need to know what it can hold, what it cannot, and which questions to ask before releasing a purchase order. Read it and you can sort a real capability claim from a copy-pasted spec sheet in one call.
In this article
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Key takeaways
Where a Puma P240 lathe fits and where it does not
Use this as a first filter before you send a drawing.
| Part type | Fits well | Marginal | Move elsewhere |
|---|---|---|---|
| Shafts Ø10–120 mm | Yes, with a steady rest | Long L/D over 10:1 | Shafts over 500 mm |
| Bushings and sleeves | Yes, bar feed friendly | Thin wall under 1 mm | Very thin, chatter-prone walls |
| Small housings | Yes, if OD is under 250 mm | Interrupted cuts in hard steel | Housings over 300 mm OD |
| Prototype runs | Yes, 1 to 50 pieces | Mixed material trials | Production over 10,000 pieces |
| Hardened steel parts | Only under 45 HRC | 45–55 HRC with CBN | Over 55 HRC, grind instead |
| Tight bore tolerances | ±0.005 mm achievable | Under 6 mm bore | Micro bores below 2 mm |
What a 2002 Puma P240 CNC machine can actually hold
The Puma P240 is a slant-bed turning center from the early 2000s. Original specs put it in the 8-inch chuck class with a 2-axis turret and a tailstock. That means a bar capacity around 50 mm and a maximum turning diameter near 250 mm, depending on the specific build. If a shop quotes a 400 mm diameter flange on this machine, ask which one they really mean.
Tolerance is where age shows up. A maintained machine can hold ±0.005 mm on diameter for short parts in aluminum or free-machining steel. Push the length-to-diameter ratio past 6:1 without a steady rest and that number drifts. Thermal growth over a long run adds another 0.01 mm to 0.02 mm if the shop does not warm the spindle first.
Surface finish is more forgiving. Ra 0.8–1.6 μm is routine with a sharp insert and the right feed. Ra 0.2–0.8 μm needs a wiper insert, low feed and a rigid setup. If the drawing calls for Ra 0.4 μm across a long shaft, plan a second op or a different machine.
The turret is the weak point on older units. Index repeatability of ±0.005 mm is the target after rebuild. Beyond that, tool offsets start chasing themselves and bores go oval. Ask for a turret index test, not just a spindle runout number.
Maintenance signals that separate a runner from a relic
Two Puma P240 lathes from the same year can behave like different machines. The gap is almost always maintenance, not hours. A lathe with 60,000 spindle hours and fresh bearings will out-turn one with 20,000 hours and original grease. So the first question is not how old, it is what was replaced.
Ballscrew backlash is the number that matters most. New screws hold 0.005 mm backlash. Worn ones run 0.03 mm or worse and the control has to compensate. Compensation is fine until the wear becomes uneven along the screw, then the middle of the travel is loose and the ends are tight. Parts made at different Z positions come out different sizes.
Spindle runout should sit under 0.005 mm TIR at the taper. Above 0.01 mm, every part gets a taper you cannot cut out. Check the spindle taper for fretting and blue marks. A scored taper means the tool holder is not seating, and no amount of programming fixes that.
Way lubrication and turret clamping are the cheap checks. Dry ways wear the slide faces and kill finish. A lazy turret clamp shows up as position drift after a heavy cut. Both are visible in ten minutes with a dial indicator and a flashlight. Ask for the readings, not a verbal yes.
Why the hourly rate is not the real price
Older machines often carry a lower hourly rate. That looks good on the quote and can be worse on the invoice. A worn lathe runs slower, needs more in-process checks, and produces more scrap. If the shop passes that scrap back to you as a rework charge, the cheap rate disappears.
Setup time is where small batches live or die. A 2-axis lathe with a quick-change turret can be set up in 30 to 60 minutes. Add a steady rest, a custom soft jaw, or a bar puller and that climbs. For a 10-piece order, setup can be half the price. Ask how setup is billed and whether it is shared across repeat orders.
Programming matters too. A shop with a proven post-processor and a tool library will get first-part-good faster. A shop that programs at the control will burn hours proving a simple profile. Ask whether they program offline and whether they simulate before the first cut.
Lead time on a maintained lathe is usually short because the machine is free. The risk is the opposite: an old lathe that breaks mid-run has long downtime for parts. Ask what spare turret and spindle parts they keep on the shelf. If the answer is none, add slack to your schedule.
Six questions that expose a weak capability claim
Anyone can list a machine model on a website. The difference is whether the shop can show you the machine doing your kind of work. Start with a first-article report from a similar part. Not a sample from five years ago. A report with the drawing, the measured values and the gauge used. If they cannot produce one, that tells you something.
Second, ask for the machine's last calibration or ballbar test. A ballbar plot shows circularity and backlash in one picture. A shop that tracks this knows its machines. A shop that does not is guessing at capability the same way you would be.
Third, ask who runs the lathe. A dedicated turner who has run the same machine for years is worth more than a new model. Fourth, ask about tooling. Carbide inserts from a known grade and a real tool presetter beat a drawer of unlabeled holders.
Fifth, ask about inspection. In-process checks with a micrometer on every tenth part, plus a final report, is the minimum. Sixth, ask what happens when a part is out of tolerance. A shop that reruns it without argument is easier to work with than one that negotiates. Get the answer before the PO, not after.
Step by step: qualifying a shop with a Puma P240 CNC machine
Run these in order. Each step is cheap and filters out the wrong shops fast.
- 1Send one representative partPick the part with the tightest tolerance and the worst L/D ratio in your batch. Send the 2D drawing with GD&T, not a STEP file alone. A shop that quotes without asking about datums is guessing.
- 2Ask for the machine's maintenance recordRequest spindle runout, ballscrew backlash and turret index repeatability. Target values: under 0.005 mm TIR, under 0.01 mm backlash, ±0.005 mm turret repeatability. Anything above that needs a plan.
- 3Request a first-article reportThe report should list each critical dimension, the nominal, the actual and the gauge used. A CMM report with no gauge list is not enough for a ±0.005 mm feature.
- 4Check the setup plan for your batch sizeFor 1–50 pieces, confirm the bar feeder or chuck jaws, the steady rest if L/D exceeds 6:1, and whether setup is billed once or per order. Ask about soft jaws for thin-wall parts.
- 5Confirm material and heat treat handlingTurning 4140 pre-hard or 17-4PH is different from 6061. Ask for the insert grade and the surface speed they plan to run. Above 45 HRC, expect a grind step, not a turned finish.
- 6Agree on inspection and rework termsSet the sampling rate and the report format before the run. Confirm the rework policy in writing. A shop that offers free rework on genuine quality problems is easier to hold to a schedule.
- 7Start with a small pilot orderRun 5 to 20 pieces before releasing the full batch. Use the pilot to measure cycle time and real tolerance spread. Then scale. This step costs less than one scrapped production run.
Common questions
Can a 2002 Puma P240 still hold ±0.005 mm?
Yes, on short parts in aluminum or easy-to-cut steel, if the spindle, ballscrews and turret were rebuilt and the shop warms the machine before the first cut.
On long shafts or hard materials, expect ±0.01 mm unless the shop adds a steady rest and checks thermal drift.
What is the maximum part size for this lathe?
Roughly 250 mm turning diameter and about 50 mm bar capacity, depending on the chuck and spindle bore of the specific build.
Parts beyond that envelope should be quoted on a larger turning center. Ask the shop to confirm the actual machine envelope, not the brochure number.
Is an old lathe cheaper than a new one?
The hourly rate is often lower, but setup, scrap and inspection can erase the difference on tight parts.
For simple parts in small batches, an older machine is usually the better value. For high-volume or hard-material work, a newer machine with live tooling wins.
What should I ask before sending a purchase order?
Ask for spindle runout, backlash, turret repeatability, a first-article report from a similar part, the setup charge, the inspection plan and the rework policy.
Get the answers in writing. A verbal yes on tolerance is not a capability statement.
Does an older machine limit the surface finish I can get?
Ra 0.8–1.6 μm is realistic with a sharp insert and the right feed. Finer finishes need a wiper insert and a rigid setup.
If the drawing calls for Ra 0.2–0.4 μm across a long surface, plan a second operation or a different process.
How do I check the shop, not just the machine?
Ask who runs the lathe, how parts are programmed, and what gauges are used on the floor.
A shop that tracks its own machine data and shows you the numbers is a better bet than one that only talks about the brand.
Send your drawing and get a real capability answer
We quote turning work against the actual machine envelope, not a brochure. Send a drawing with tolerances and we will tell you if the job fits a Puma-class lathe or belongs on a bigger center. Quotation and DFM feedback within 12 hours. Parts ship in 3–5 days.
12-hour quote100% inspectionNo MOQNDA on request
More from the shop floor
We publish setup notes, tooling trials and inspection data from the factory floor.
