Machining inserts part numbers

[JAParticipant @ja]

Please could someone explain, or give a reference to understanding, insert part numbers. I am sure there is rhythm and reason in system, probably an ISO one, but I am about to order some specialist inserts and feel that I could drop down a rabbit hole.

JA

[Andrew EntwistleParticipant @andrewentwistle]

https://www.cutwel.co.uk/blog/learn-the-turning-tool-iso-code-system

[JA]

On 18 September 2026 at 14:16 JA Said:

Please could someone explain, or give a reference to understanding, insert part numbers. I am sure there is rhythm and reason in system, probably an ISO one, but I am about to order some specialist inserts and feel that I could drop down a rabbit hole.

JA

ISO may not be specialist, there’s lots of proprietary codes for odd  inserts. Also there are codes that relate to material designed for, toughness etc.

APT  will sell you a single insert if you are buying the tool holder as well

[JAParticipant @ja]

Andrew, many thanks.

Before reading your reply I ordered what I thought I wanted from Cutwel. Thankfully I did not mess-up.

Their guide is going to be downloaded and safely stored on the computer.

JA

[old martParticipant @oldmart]

We have at least a dozen different sizes and shapes for most uses, if starting out, it depends what size of lathe you have.

APT are excellent for home users, as already mentioned they sell a limited range of inserts in small quantities so the home user won’t be stuck with a box of ten that don’t work well.

When you do decide, it pays to get some inserts for aluminium, often designated H0 they work well on steel when taking small and tiny finishing cuts. I used one on a hardened drill blank carefully and got excellent results.

[bernard towersParticipant @bernardtowers37738]

Sandviks catalogue is very good and has pages explaining the letters and numbers for inserts.

[DalboyParticipant @dalboy]

I found this very helpful. It is from the MSC catalouge.

[JAParticipant @ja]

Thanks all.

Just an aside. Inserts ordered at 3.20pm yesterday afternoon and should arrive in an hours time by DPD electric van.

JA

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