Let me see if I can explain the problem with your original solution. You have six unbound controls on the form which may or may not hold a value. Usually, we see the problem you are having on continuous forms where the problem is more obvious. We would only see it on a single record form if the schema violated first normal form which yours does as was alluded to by Gasman. So, although the suggestion made by
@theDBguy gets around the issue, it still leaves you with an incorrect table schema and potential future problems if your product line changes to include products with more gages.
Anyway, each unbound control is a property of the form because it is not bound to the underlying data source. As such, each control can only hold a single value at one time. What you are seeing is "bleed" through. Record 1 has 5 gages, you scroll to record 2 which has 3 gages. You see the first three gages but you also see gages 4 and 5 from the previous record.
Although I prefer
@theDBguy 's solution, a different way to solve the problem would be to add code to the form's Current event which clears all 6 controls. Then, if this is an existing record, repopulates the unbound controls for the gages that are populated.
The best solution, however, is to always normalize your schema. In the long run, you will have fewer "challenges" going forward and will NOT require application modification if you use the proper many-side table structure for your gages. Show them in a subform. with a combo and an unbound control using the technique
@theDBguy suggested. The subform will show 0 - n rows for each device depending on how many gages are defined. There will be no bleed through because only the correct number of records ever show.