service, effects and ball contact

Hi Mr. Rosario

I saw your video about service, it is excellent. I have some questions:
Which is the appropriate point of contact for each service? Is it the one you show in the video? Is it generates greater effect the closer to the tip of the bat hits the ball? In  a spin service,  how far the ball travels attached to the blade?inches? millimeters?

What do you think about a service that in Spain we name "bomba" (bomb)? It is a long service, with non effect, (zero spin) by stroking the ball flat, trying to be explosive, very long and very fast. Phillippe Gatien talks about this serve in his book "Tennis de table". 

Excuse me for my english, I hope you can understand me. 

Thank you.

Hi Carlos,

The faster your bat is travelling when you hit the ball the more chance you have of generating spin.  The outer tip of the arc has to be moving faster.

The other key factor is the contact of the bat on the ball.  The more brushing effect you can get on the ball the better the spin will be.

The long fast serve can be effective as a surprise, especially if the opponent is good at the short game and is starting to move in when you are serving.