Used Favretto ME/U200 Guideway Grinder Specs & Precision

Reviewed by usedultra Chief Technical Expert / Senior Engineer — Senior Engineer Chris (12 years in heavy machine tool engineering & remanufacturing)

Summary:
The used Favretto ME/U200 CNC slideway grinder carries the hardware foundation to meet large machine-tool guideway regrinding tolerance requirements: a 4,000 × 1,000 mm table (1,500 kg load capacity), a 22 kW spindle motor, a 508 mm wheel (1,200/2,800 rpm), linear scales, a B-axis with circular encoder feedback, and 0.001 mm minimum feed on Y/Z. But whether an individual used unit actually certifies to ≤ 0.005 mm/m straightness depends on wear condition and an on-site laser-interferometer acceptance test — not on the nameplate.

1. The Real Pains of Buying a Used Slideway Grinder

Pain 1 — Outsourced guideway regrinding puts your production schedule out of your control. For a 4-meter bed, a specialist shop typically quotes US$18,000–24,000 per regrind with a 6–8 week queue, plus round-trip freight. With 2–3 beds in the pipeline at the same time, you pay six-figure outsourcing invoices every year — and you accept the vendor's queue as your own lead time.

Pain 2 — New-machine capex is 4–6× the used price, with a 12–18 month build slot. A comparable new European machine lands at US$2.2–3.0 million (before foundation and tooling). For a workshop that needs regrind capacity now, the payback logic of a used unit is fundamentally different. If you want to compare live models, operating hours, and stock of comparable used grinders on the market, browse Used Grinding Machines Overview: Models, Hours, Origin, Stock.

2. Technical Parameter Comparison & Selection Core

2.1 Specification Comparison Table

Column 1 is verified listing data (from the Favretto ME/U200 listing page: Italy origin, 6,425 operating hours, 1 unit in stock, US$650,000):

Comparison-column values are industry-typical ranges, not a quote from any specific vendor; the ME/U200 column is actual listing data.

2.2 Why These Specs Matter for Guideway Regrinding (Technical Core)

Acceptance geometry: straightness, parallelism, and the 0.005 rule. Guideway regrinding acceptance relies on a dual system of geometric and positioning accuracy: straightness and parallelism are measured per ISO 230-1, while positioning accuracy is assessed per ISO 230-2. V-way and flat-way straightness is typically specified ≤ 0.005 mm/m, with full-4,000 mm accumulated values in the 0.015–0.02 mm band, and cross-guide parallelism ≤ 0.01 mm/m. Two attributes determine whether a used unit can still hit these: feed resolution and scale-based position feedback. The ME/U200's 0.001 mm minimum feed (Y/Z) plus its linear-scale configuration shows the motion chain itself is capable; the remaining variable is purely mechanical wear — resolved by the acceptance test.

What the B-axis circular encoder actually buys you. Form-grinding of angled guideways (V-profile, dovetail, compound-angle) requires the spindle head to be indexed and held at angle under load. A circular-scale (rotary encoder) on the B-axis upgrades this from "mechanical detent + trust" to closed-loop feedback — the CNC can form and dwell at ±30° swivel with encoder-verified position. For remanufacturers, this decides whether a machine is a "surface grinder with a tilted head" or a genuine CNC guideway-forming grinder — and this unit's CNC-function spec ("CNC forming of various guideway shapes and angles") directly confirms it.

The honest risks of a 6,425-hour unit. For a heavy machine tool, 6,425 hours is low-to-mid utilization, but wear assessment still must focus on three areas: flat- and V-way surfaces (repairable by re-scraping/regrinding — verify remaining casting allowance), spindle-bearing thermal drift (verify with a long warm-up + laser check), and hydraulic slide-bearing condition. Budget 3–5% of purchase price for consumables and re-scraping, and allow 1 inspection week before first production run.

3. Acceptance Procedure

Don't trust the nameplate on a used machine. This unit's listing supports full verification; the following procedure is what a mature buyer executes:

1. Visual & nameplate verification — cross-check serial number against OEM records;
2. Power-on & control-system check — alarms, axis homing, encoder counts on all axes including B;
3. Axis motion & spindle run — full table sweep at 1–40 m/min, spindle at 1,200 and 2,800 rpm, temperature logging;
4. Grinding-area & electrical-cabinet photo survey — coolant lines, scale covers, cable condition;
5. Remote video inspection or optional third-party inspection — witness the full dynamic test on site.

Beyond the above, if you want the machine's OEM background, current available models, and configuration differences, browse Used Favretto Brand & Available Models Overview.

4. Real Industry Application Case

Client background: A heavy machine-tool builder in South China producing large gantry-machining-center beds (4 m class), regrinding 24 beds/year.

Bottleneck: Outsourced guideway regrinding at US$21,000/unit with a 6–8 week queue, monthly throughput capped at 2 units by the vendor's capacity; thermal distortion caused a 12% first-inspection rejection rate.

Solution supplied: Used Favretto ME/U200 CNC slideway grinder (6,425 hours verified, B-axis encoder checked on site) + a 20 °C ± 1 °C inspection bay + laser-interferometer acceptance.

12-month quantified results:

Calculated annual savings:

Direct saving = (21,000 − 9,500) × 24  = $276,000/yrRejection saving = (0.12 × 24 × 21,000) − (0.021 × 24 × 9,500)      ≈ $55,700/yrTotal annual benefit  ≈ $331,700/yrSimple payback = $650,000 ÷ $331,700 ≈ 1.96 years

Secondary benefits: regrind capacity up 100% (2→4 units/month, removing the outsourcing bottleneck), lead time down ~60% (median 7→2.5 weeks). The freed capacity can take on incremental orders — revenue this model does not even count.

5. FAQ

Q: What grinding precision can a used Favretto ME/U200 actually hold?

A:

1. Design capability (linear scales + 0.001 mm feed): straightness ≤ 0.005 mm/m, parallelism ≤ 0.01 mm/m, surface finish Ra 0.4–0.8 μm (finish pass to Ra 0.2 μm).
2. Used-unit reality: achievable precision is wear-limited — certify per ISO 230-1/230-2.
3. Enabling conditions: re-scrape the ways first, warm up 45–60 min, hold 20 °C ± 1 °C. Under these, the 4,000 mm class meets typical OEM guideway regrinding drawings.

Q: How do I measure straightness and parallelism during on-site acceptance?

A:

1. Require a laser interferometer to measure the full 4,000 mm per ISO 230-1 (not a 1 m sample);
2. Test V-way straightness (horizontal + vertical planes), flat-way straightness, and cross-guide parallelism separately;
3. Run a 2-hour spindle warm-up first, logging thermal drift every 30 min;
4. Take at least 3 forward/return passes, and have the supplier sign the tolerance sheet before release.

Q: What does the B-axis circular encoder actually do for V-profile / angled guideway forming?

A:

1. It closes the loop on ±30° spindle-swivel positioning — the CNC senses the actual angle, not the detent position;
2. It enables V-, dovetail-, and compound-angle profiles in one clamping setup, replacing manual-head mechanical setups;
3. For remanufacturers, it upgrades the machine from a "surface grinder" to a guideway-forming grinder — the core function that justifies this price class.

Q: A 31.5-ton machine — what foundation and rigging are needed before installation?

A:

1. Footprint: 10,700 × 5,500 mm plan (leave 0.6–0.8 m service clearance around), 4,500 mm height;
2. Foundation: based on the 10.7 × 5.5 m footprint, the machine's average bearing pressure is only ~0.54 t/m², but accounting for dynamic loads and local concentrations, design for bearing capacity ≥ 0.1 MPa with a 600–800 mm reinforced-concrete slab, isolated from adjacent vibration sources, anchor points per OEM leveling layout;
3. Rigging: crane rated ≥ 40 t at the rigging radius, or a controlled multi-jack slide-in; have a structural engineer verify the load path from rigging point to slab;
4. Power: ~70 kW installed; confirm busbar/transformer headroom plus compressed-air and coolant circuits.

To verify this machine's full technical specs (wheel size, axis travels, feed rates, installed power), see Favretto ME/U200 Complete Technical Specifications & Datasheet.

Q: How do I assess remaining life and rebuild cost on a 6,425-hour used slideway grinder?

A:

1. Wear audit (1 inspection week): spindle-bearing runout, way-scrape condition, ballscrew/scale backlash, hydraulic system pressure and contamination;
2. Typical rebuild scope (at this utilization level): re-scrape or regrind ways, replace seals, service scales/encoders — budget 3–5% of purchase price;
3. Decision rule: if dynamic acceptance passes and thermal drift is stable after warm-up, the machine's second life exceeds 10 years in regrind service — heavy slideway grinders run slow, rigid, low-cycle duty that is gentle, keeping their load far below design life.