The one with the grips is definitely an Iver Johnson. The other could be any of a dozen different "suicide specials" (old cop term for these inexpensive revolvers that were produced by the ton until 1968).
It's difficult to fix this type of gun. They were not designed to disassemble (and especially not to REASSEMBLE) easily and even if you nail down the make and model, some companies made several variations of the same model with few, if any interchangeable parts. Further, parts were fitted to the individual gun and sometimes will not fit in another identical piece. Repair, repolish and re-nickel plating might make your friend's $5.00 clunkers into $80.00 clunkers...after you spent untold hours and cash hunting down the parts, reworking them to fit and work properly.
After all that, if you're doing the work for fun and information, go for it. I'd drag the little revolvers to gunsmiths (beg or buy spare parts from their scrap bins) and the parts guys at gun shows.
Alternatively, you could save a lot of time, money and aggravation by just picking up a couple of working Iver Johnsons, Harrington and Richardsons, Forehand & Wadsworths or Hopkins and Allens in working condition. A couple of local gunshops here in Pa. usually have a few lying around for not a lot of money.
The ones you have could be cleaned up and hung on the wall or put into a shadowbox for display.