Hi,

In JEE Mains Paper 2, which is for B.Arch or B.Planning courses, the cut-off can be around 30-45 marks. Around, 2-3 lakh candidates sit for Paper 2 every year. 

In JEE Mains Paper 1, an SC candidate can expect a cut-off of 31-36 marks. Around, 9,65,000 students appeared for JEE Mains Phase 1 this year. A percentile of 60+ can be considered safe in the SC category.

Hope this helps.

Cheers!