8 on Mon....08 8 on Tue.....16 8 on Wed....24 8 on Thu.....32 8 on Fri.......40 14 on Sat...54 14 on Sun..68 8 on Mon...76 8 on Tue.....76 8 on Wed....76 8 on Thu.....76 8 on Fri.......76 14 on Sat...80 Someone correct me if I'm wrong. Like I said earlier, it's been a while since I used paper. 70 in 8 days is the rule right?
Your math is right. Only problem is we don't know anything about OPs hours on his day job. Legally once you start driving a CMV (defined as ANY commercial vehicle over 10,001) you are subject to the HOS rules regardless of local or OTR. If OP stays 100% legal until we know how many hours are on duty on this day job we can't advise the weekend available hours.
My advice has all been on the assumption of working 40 hours. The OP has not refuted that in any way. So, assume, assume, assume.
In this case the OP would have 20 hours left. To stay 100% legal OP would not be on a 70 hours 8 days schedule. It would be 60 hours in 7 days. In all honestly though a sit down with the weekend company should happen so everybody is on the same page. Edited to add. Before everybody gets all excited and lets me know it is up to the carrier what schedule a driver runs under. I know most use the 70 in 8 days. Just be advised a carrier has to operate 7 days a week to use the 70 in 8 days. Chances are driver will be OK to go the full 70 legally. (grey area again) the FMCSA might interpret a weekend only driver to be on a 60 in 7 days. If I were doing this I would specifically want to know what schedule I was operating under.
Sorry op, there are other things you can do without getting into trucking. Just getting the license will cost you time and money.
For what it's worth, I wasn't trying to get ya. Just trying to make sure I was thinking about it correctly.