What sort of backlash can I expect? 40µm is plenty. These days IC's have pin pitches down to 0.5mm. I'm not looking for an automated solution. I tend to use a lot of the same parts so it would save a lot of time just to load one BOM line at a time so that the machine can automatically pick each part up once told where the first one on the tape is and be driven to the location where it is set down. My plan would be to feed it the coordinates of each part on the board but that I give it the OK before placing a part so that I can make a manual adjustment if required. So for the average passive that there are a lot of and that do not require too much precision it will probably work automatically and quickly but the IC's that I won't be able to pick up reliably anyway I can move precisely into position by hand after it goes to about the right location.