Published: 25 October 2026
Separate the steel grade from the coating
HSS describes a family of high-speed tool steels. M35 and M42 identify cobalt-alloyed grades; cobalt is part of the steel, not a gold-colored surface coating. Erasteel identifies E M35 as AISI M35 / HS 6-5-2-5 and E M42 as AISI M42 / HS 2-9-1-8. Its M42 sheet emphasizes hot hardness. These grade sheets describe steel, not a performance certificate for an offered FLUTEX drill.
When an offer says HSS-Co or HSS-E, ask for the actual grade designation. Keep substrate, coating or finish, and manufacturing method as separate fields. Do not infer grade from color or from a hardness label alone.
Build a specification that can be compared
| Decision | Information to confirm |
|---|---|
| Workpiece | Alloy/steel grade, condition, thickness and interrupted features. |
| Hole | Diameter, depth, through or blind, tolerance, burr limit and finish. |
| Drill | Grade, standard/reference, flute length, overall length, shank and point geometry. |
| Setup | Hand-held or fixed machine, chuck/holder, available lubrication and workholding. |
For a replacement, include the full marking and drawing. DIN 338, DIN 340 and DIN 345 identify different drill forms; a similar diameter does not make them interchangeable. Check the actual dimensions and shank against the required holder.
Is M42 automatically better for aluminum?
No. Treat that as a selection question, not a ranking by grade number. For an aluminum-profile job, tell the supplier the known alloy, hole depth, exit condition and machine. Ask for the drill geometry and chip-clearance arrangement intended for that application.
For a hand-held job, state that explicitly. A result obtained in a rigid production machine does not establish the same result in a portable drill. Compare the complete offered tools rather than changing only the steel name on a quotation.
When a different tool material is proposed
If the supplier proposes carbide, request the exact tool reference and a recommendation for the machine, holder and operation. Do not substitute a carbide drill using only the dimensions of the previous HSS drill. Confirm reach, clamping length, coolant arrangement and the allowed application together.
For stainless or other demanding materials, include the material condition and the observed failure: edge wear, chipping, poor chip evacuation or hole-quality loss. This gives the application team a useful starting point; it does not by itself diagnose the cause.
Record a repeatable trial
Before comparing two drills, agree on the acceptance criteria. Record the drill reference, machine, work material, lubrication, actual programmed values and number of acceptable holes. Keep burrs, hole size and tool condition as separate observations.
Change one documented variable at a time where the approved process permits it. Ask the manufacturer for operating values for the exact tool; this guide supplies no universal drilling speed or feed. The linked FLUTEX calculator is for milling formulas, not a drilling-cycle recommendation.
Send a clear Saudi Arabia RFQ
Send the specification, current tool marking, required quantity and delivery city. Ask the quotation to identify the offered grade and geometry, any alternative, availability and lead time. A listed product family is an enquiry route, not confirmation that every grade or diameter is stocked.
References and scope
Technical references do not establish approval, partnership or certification of a FLUTEX product. The checklists organize selection and evidence; operating instructions come from the tool and machine manufacturers.
