Hot plate for reflowing BGA balls?

[zero9]

I am lately repairing units which uses 4-6 bga IC and i reball using non-direct heat stencils and hot air afterwards to melt solder balls.
That process is a bit time consuming and i am looking ways to bit speed up that process.
I was thinking to buy hot plate and after all IC have their solder balls aligned on their pads - use hot plate to re-flow solder for all of them rather than go one-by-one with hot air.

Question - someone use this method with hot plate and it might be faster than using hot air and its usable method? Even with low air flow i sometimes manage to move balls off the pads.

[sn4k3]

I have one of this: https://www.banggood.com/100x100mm-946C-110-220V-450W-Hot-Plate-Preheat-Preheating-Desoldering-Station-for-PCB-SMD-Heating-p-1348274.html

Cheap and make it service

The way to keep balls in place with hot air is use a good sticky flux and low airflow, is all a matter of pratice

[masterx81]

I have problems also if there is too much flux, or also when in a spot there is a bit more flux, that when become liquid due to heat, move some balls due to superficial tension 
The air of my station in low setting not move the balls enough to create problems.
In any case i preheat the chip and do only the final weld with hot air. Maybe doing all the work with big bga and heating all the package with only low aiflow may cause some problem

[sn4k3]

I have problems also if there is too much flux, or also when in a spot there is a bit more flux, that when become liquid due to heat, move some balls due to superficial tension 
The air of my station in low setting not move the balls enough to create problems.
In any case i preheat the chip and do only the final weld with hot air. Maybe doing all the work with big bga and heating all the package with only low aiflow may cause some problem

You just need a thin coat of flux, with a sticky one apply with a brush a even thin coat. Works for me.
Preheater and low airflow will also help. There's also people who put them on the PCB oven, which works best
It's all a matter of practice.