On 98s and Siamese, do any have to have an extractor cut? I have several and none have extractor cuts and with what I have see no need for them. Am I missing something or which of these need it?

I do believe the ones with the extractor cuts are referred to as "safety breached", mainly the Yugos.

Costa Rican Model 1910 as well.

Standard 98s have no extractor cut. As stated, some do, but 99% of them do not. You aren't missing anything. Siamese do have cuts as the extractor is for a rimmed cartridge and the Yugo uses the safety breech (as stated above), which places the ammo farther into the barrel. Germans, Czechs, Polish, and most everyone else, use the standard 98 bolt which the extractor is flush with the bolt nose. Makes for a thin extractor lip though. When the US stole the design for the Springfield (from a Mauser 93), we decided to use a cone barrel breech to insure better feeding (it doesn't), so we needed to put a cut into that cone. Other actions use cuts; I can list them if you want.

butch i set my barrels as tight to the extractor as possible and on 80 plus builds have never had a problem. i might be wrong but in what i have built no blown cases or extracting problems
Preacher Jim

In speaking with a gentleman in Florida who has over 1100 Mausers, I guess maybe some 98S and the Siamese may need extractor cuts. I have never personally had to do it. I have learned never to say never.
One that he mentioned is a Lithuanian and certain Peruvians.

I have had two Yugos and a 1909 Peruvian (Oberndorf) rebarelled. All three had extractor cuts originally, none needed the cut when the barrels were replaced.

For discussion. Rimmed cartridges that have to headspace off the rim? 98 and Siamese action differences?

Siam Mausers differ from the rest of the military Mausers in that they were designed to use a rimmed cartridge.