- 98% satisfied customers
- 72h delivery
- 30 dni na zwrot
Description
Taper shank roughing reamer Ø19.7 for metal — technical data
NRTa — shank-type roughing reamer, Morse taper shank, HSS
| Technical Data | |
|---|---|
| Cutting diameter D (h8) | Ø19.7 mm (19.667–19.700 mm) |
| Morse taper | MT2 |
| Flute length l | 44 mm |
| Overall length L | 203 mm |
| Type | NRTa — shank-type roughing reamer, Morse taper shank |
| Material | HSS (high-speed steel) |

Manufacturing tolerance h8 for a diameter of 19.7 mm
| Class | Deviations [mm] | Dimension [mm] | |
|---|---|---|---|
| h8 | 0 / −0.033 | 19.667 – 19.700 | VERSION |
Cutting diameter 19.7 mm prepares the hole for a finishing reamer Ø20 H7 — the roughing reamer leaves an allowance of approx. 0.3 mm on the diameter for finish reaming.
Cutting data for the roughing reamer Ø19.7
Indicative values for Ø19.7 mm
| Material group (ISO 513) | Vc [m/min] | fz [mm/tooth] | n [rpm] Ø19.7 |
|---|---|---|---|
| PStructural and carbon steel | 8–10 | 0.16–0.20 | 129 |
| MStainless steel | 2–3 | 0.16–0.20 | 32 |
| KCast iron | 3–5 | 0.16–0.20 | 48 |
| NAluminum and light alloys | 12–16 | 0.20–0.24 | 194 |
Vc — cutting speed, fz — feed per tooth (catalog values for HSS, selected for a diameter of Ø19.7 mm). Spindle speeds were calculated for the lower end of the range: n = (Vc × 1000) ÷ (π × D). Start with the lower values and adjust according to the material and clamping rigidity.
You may also need: Cutting parameters calculator
Applications of the roughing reamer Ø19.7 for metal
Rough machining of holes before finish reaming
Taper shank roughing reamer Ø19.7 for metal Morse MT2 — NRTa shank-type roughing reamer made of high-speed steel (HSS) HSS. Used for preliminary reaming of drilled holes — it removes a larger allowance, corrects the hole axis, and prepares the hole for a finishing reamer. The tool face has a ~45° lead-in chamfer for centered entry, while the guide margins on the cutting edges keep the tool aligned with the hole axis.
The Ø19.7 roughing reamer for metal straightens the hole after drilling: it corrects form errors, aligns the hole axis, and leaves a uniform stock allowance for finishing. Diameter 19.7 mm corresponds to a finished hole of Ø20 H7 (allowance of approx. 0.3 mm on the diameter). Cutting edges with large flutes efficiently evacuate chips when removing a larger allowance, while HSS withstands heavy cutting conditions. This diameter range is common in sliding fits: pins, shafts, plain bushings, and dowel pin holes in housings.
Workpiece materials
Guidelines for correct reaming
- After rough reaming, ream to final size with a finishing reamer Ø20 H7 — stock allowance of 0.3 mm on the diameter.
- Use coolant (emulsion or cutting oil); cast iron can be machined dry.
- Withdraw the tool without reversing its rotation — reverse rotation damages the cutting edges.
Frequently asked questions — roughing reamer Ø19.7
A roughing reamer removes a large allowance after drilling, straightens the axis, and improves hole shape, but does not provide H7 tolerance. The hole is brought to final size with a finishing reamer.
The 19.7 mm diameter is selected for a finished hole of Ø20 H7 — after rough reaming, an allowance of approx. 0.3 mm remains on the diameter for the finishing reamer.
The short NRTa is more rigid — better for standard holes when clamped close to the spindle. The long NRTb with spiral flutes reaches deeper and evacuates chips from deep holes more efficiently.
Reviews
No customer reviews for the moment.
Shipping
All orders are delivered by courier company GLS. For orders exceeding 369 PLN gross shipping is FREE
| Courier GLS | Przelew24 / Prepayment | 14,76 zł gross | Delivery time 1 working day |
| Courier GLS | Cash on delivery | 17,26 zł gross | Lead time 1 working day |
Recommended for you
Użyj strzałek, aby zmieniać zdjęcia. Powiększaj przyciskami albo gestem szczypania. Zamknij galerię klawiszem Escape.
This website uses its own and third-party cookies to improve our services and show you advertising related to your preferences by analyzing your browsing habits. To give your consent to its use, press the Accept button.