I'm being told by a welding engineer that I just don't need to exceed 35,000 Rpms with the carbide burrs.  Apparently size 1/4, 5/8, etc, doesn't matter.   I've read from a few catalogues that 1/4 shouldn't exceed 22,000?  Something like 15k rpm for 5/8. Weld base metal is 4130. Apparently they only have standard cut carbides... Even though in production ... some clean up is with carbides, I would think fine would be better than standard fluting.  I've only seen 25,000 dye grinders around the shop.  I've been using the carbides, getting the job done, but I'm wondering what's correct?  The abrasive disks are 13,500 (za-36).. Being used on 25k die grinders as well.  Any info/insight is appreciated.

1/4 shank, 1/4 flute/burr sc-1, sa-1, sd-1, etc