How can I stop two Chest Carts, pulled by a Locomotive, at two adjacent Item Loaders until they have fully emptied the contents of the double-wide Chest attached to the Loaders?
I'm using a train to collect output from my Quarries. The train consists of a Locomotive pulling two Chest Carts (with a passenger Cart "caboose"---oh! CovertJaguar! Caboose Cart!). My Quarries output into a double-wide Chest attached to two Item Loaders, with two Train Lockdown Tracks below them. The Item Loaders are configured in T ("Transfer") mode, with a "Chest Cart" filter (so they don't stop the Locomotive). Ideally, the Locomotive would drive past, then the Lockdown Tracks would stop the Chest Carts while the Item Loaders emptied the Chest contents into them before sending everything on its way.
However, the Chest Carts don't stop. At all. I think the problem is that, when the Item Loaders unlock the Train Lockdown Tracks for the Locomotive, they don't have enough time to lock up again before the Chest Carts have also gone past. I've tried everything I can think of --- using only one Lockdown Track, using Wait mode on the Loaders, removing the Chest Cart filter, etc. None of it works (or if it does, it causes other problems). I'm starting to consider setups that strike me as a little overcomplicated (like using Detector Rails and Timers and State Cells and Item Detectors and ...), but I figure I've got to be missing something, as Item Loaders are supposed to work with trains according to the wiki.
Anyone know what I'm doing wrong? Thanks in advance!