Have you asked Chester after all they sell the cutter they should know the type of inserts it will take.

Look again they are square

There is a useful guide to decoding inserts here:

https://www.cutwel.co.uk/blog/learn-the-turning-insert-iso-code.html

You need the first seven fields of the code.

Given that they are square, with no hole, that reduces the possible codes considerably.

Any codes you cannot positively identify, guess at a letter and type the result into Google. If there is no-one supplying inserts with that code, cross that possiblity off the list.

Just from observation, the first letter of the code is S.

Measure as best you can the second one.

In practice, the third one will be M.

The next easiest to identify is the fourth field: it will be F, N or R.

Fields five and six from measurement.

Field seven, try 02, 04 and 08.

Edited By DC31k on 25/07/2023 07:12:40

The insert type doesn't seem to be mentioned on the appropriate Chester product page. That's a red flag and means I'd avoid the cutter like the plague. The inserts are probably not standard and/or not common. So you have to buy them from Chester.

Andrew

Chester do list them, they are in the OP's original link.

There are several of the hobby suppliers who don't give the codes for the inserts, in many cases it is so people go back to them for inserts rather than sourcing from elsewhere

It's a stock code, not an ISO insert type. Which is why i said the insert type wasn't mentioned. Fine if one wants to order from Chester, useless if one wants to order from elsewhere.

Andrew

This one, labelled Clarke, looks identical:

https://www.clarketooling.co.uk/product/clarke-2-mill-cutter/

clarketooling is one of Chronos' many aliases.

https://www.chronos.ltd.uk/product/milling-cutter-2-2/

Clarke stuff is available from Machine Mart.

https://www.machinemart.co.uk/p/2in-mill-cutter-2/ (Note clearance price compared to other suppliers full price).

Machine Mart's spares email or phone might be a possibility for a lead.

I assume you have this mill and are looking for replacements?

This guide should help:

https://littlemachineshop.com/info/insert_charts.php

1. First letter is shape (S for square)
2. Relief angle, you need to measure that (or choose another one more to your liking).
3. Tolerances, should be irrelevant for our needs. Pick the cheapest one.
4. Mounting, looks to be an N (no hole or breaker)
5. Size, again something you need to measure (I'm guessing 12 or 15)
6. Thickness, same (04 0r 06?)
7. Nose radius, same (or pick your own, perhaps 04 for fine cuts and 08 for rougher work?)

I think they are an iso insert SPKN is the geometry which is an older style of insert so similar to Sandvik SPKN 1204 ED R or L

SPKN =geometry

12 = size of the square

04 = thickness this can vary 03, 04, 05

ED = makers designation for the ground facets ( I think)

R or L = right or left hand

then add the ISO grade of carbide you require eg K20, P40, P20, etc

if you cant get the correct thickness you can always shim between the clamp screw and the insert, you can also use any square insert that will fit in the pocket of the cutter including turning inserts which are much cheaper than ground facet milling inserts hope this helps

Colin

Possibly something like this: SEKN1203AFTN-M14,

SEKN1203AFTN-M14 T25M | Secotools.com

Have you never turned any square or hex material Dave? I don't find it a problem with cabide and have also used a turning tool in a flycutter with no problem.

Like Dave Halford, I find that brazed carbides seem to chip very easily (More easily than inserted carbide tips, and are very difficult to hold to sharpen with a diamond wheel ) so avoid them wherever possible.

Howard