Here is a video of a bending exercise that might help you out.
Here is an excellent video (from Harmonica express) that people working on those low draw bends can use with a variety of harps in several different positions. Actually it can be used with any key harp, but to play along with the video and be in tune then only several different harps work (they are noted in the video itself). One advantage to this video is that it uses a melody (tabs are in the video) that many people already know, so that makes it more fun as well as easier to tell if you are making the bends accurately.
@Slim I hadn’t got to that video yet, thanks for posting.
Here is a good practice/play along video that helps perfecting low-end bends. It not only uses a melody that most people know well, it also provides the notational score, tabs for a C blues harp, an example of her playing this on her blues harp, and finally the backing track without her playing so that each viewer can play their own harp to the track. Madame Florence Gacoin-Marks has various similar videos and is a highly talented musician.
@Slim cheers, just what I need. A tune full of 3". I need the practice.
Who doesn’t ?