Aha interesting, thanks Bevan. I may have recalled the wrong numbers - I was there when we made our calibration weights but it was a while ago! Time to get the scales out!
Always make sure you don’t let it actually hit the treadle (by using a clip). The DoC guy we did a course with had a string with a base weight stainless nut and some others so you could calibrate various weights. Good to engrave the weight on it in them case someone else needs a refresh.
For the DOC200s, use a safety catch then 50g and 100g on a string and gently lower them on to fire at 100g. However, I did note recently that female weasels are typically <100g so if you’re targeting them then you may want to adjust for lower?
I tried calibrating the 250s but it became quite fiddly to get a precise calibration so I just make sure they’re going off above 100g but not much more.
@tui_kraal - we are like you and use a weight combination of washers (far cheaper than purchasing actual weights) - we can keep adding washers onto the initial weight until it fires (see picture).
Earlier this year we ordered some new traps and requested that they all fire at between 80-100 gms. We recently caught 2x weasels in a DOC200 (they are now flat fat weasels).