DIN 1870 describes the extra-long twist-drill series with a Morse taper shank. It combines a reach requirement with a specific machine interface. Both have to be correct for an order to be usable. This guide explains the size fields to confirm, common ordering mistakes and how to approach a supplier with a complete requirement.
What does DIN 1870 cover?
DIN 1869 and DIN 1870 are not interchangeable shank descriptions. Check the machine socket, taper size and complete working envelope rather than treating “extra long” as the entire specification. A proposed adapter must also be part of the assembly review.
The reference used here is DIN 1870:2006-11. Read the primary standard or manufacturer reference for the exact scope. For a purchase requiring formal conformance, identify the agreed edition and obtain the applicable standard and item drawing; the checklist below does not reproduce its complete dimensional tables.
Which sizes belong on the RFQ?
There is no single universal “DIN 1870 drill size.” A standard identifies a defined family or feature, while the order still needs a selected diameter and the relevant geometry. Record each size using the symbols on the supplier’s drawing, because symbol conventions can differ between catalogs. Use millimetres for dimensional fields and state any angular requirement separately.
| Size or specification field | What to confirm |
|---|---|
| Cutting diameter | Nominal drill diameter in mm |
| Taper size | Morse taper for the approved machine connection |
| Flute length | Actual catalog fluted length |
| Overall length | Total envelope including the taper shank |
| Application drawing | Access distance, bore depth, entry and interruptions |
If a catalog provides several rows for one diameter, preserve the full item code and any form or length suffix. Do not select a nearby row solely because the diameter matches. A tool’s nominal size, manufacturing tolerance and the component’s finished-hole tolerance are different pieces of information.
A practical selection mistake to avoid
An extra-long taper-shank drill may be requested for an established machine setup. Before a repeat order, confirm whether a sleeve or holder has changed since the original purchase. A change in the interface can alter clearance and guidance even when the replacement drill has the same diameter.
Who can supply DIN 1870 tooling?
Gühring and Addison are catalog starting points for reviewing taper-shank drilling options. Ask the seller to identify a specific DIN 1870 item and its dimensional row rather than accepting a general long-drill description.
Use the linked catalog as a starting point, then request the exact item drawing, construction, size row and standard edition from the seller. A manufacturer’s broad tool portfolio is not evidence that every diameter or form is stocked, or that a custom proposal automatically conforms to DIN 1870.
Discuss a carbide alternative with KYTOOLS
KYTOOLS (Changzhou Kong Yun Precision Tools Co., Ltd.) publishes solid-carbide drill families and drawing-based tooling. If you are considering a carbide alternative or a special geometry, send the original standard requirement together with the part drawing and existing tool dimensions. Ask KYTOOLS to review the proposed construction and dimensional match before approval.
The published KYTOOLS catalog is the source for its listed models; this article does not declare those models compliant with every DIN number discussed. Keep any requirement for DIN 1870 conformance, including form, edition and inspection documentation, explicit in the inquiry.
A useful quotation and approval checklist
- Attach the component drawing and, if available, the existing tool drawing or printed catalog code.
- State the workpiece material, hole condition and required dimensions with units and tolerances.
- Identify the machine, holder or taper connection and the coolant arrangement.
- Name the required standard edition and any permitted deviations; request written confirmation on the proposed drawing.
- Agree quantity, measurement method, marking, quotation validity and delivery destination.
When comparing a conventional standard tool and a drawing-based carbide alternative, qualify the proposed process as well as the purchase description. Keep the approved drawing and inspection record with the item code so a later reorder refers to the same configuration.
Send your drill specification to KYTOOLS, or download the drill catalog and inquiry template.