Purchased Dual Extruder V2 for TAZ5, and now seem to be skipping steps

Hello,

So my TAZ5 was printing awesomely with the normal tool head. I recently installed Piercet’s X- and Y- Open Rail axis modifications, and once I got them dialed in I was able to crank out several prints beautifully (and fast!).

So I ordered a Dual Extruder V2 and installed it, and I’m trying to print ABS using HIPS support… and it’s not going well. I probably just need to keep fiddling with my settings to try to fix most of the problems… The big thing I’m concerned about is that the printer now appears to be skipping steps, mostly in the X direction.

So far what I’m seeing is the type of thing where each layer is offset from the next by a tiny amount, so the whole print is sorta sliding off in one direction. Then every now and then, maybe every 10 to 50 layers, I’ll get a big jump (big being like 1 or 2 mm) in one direction.

I didn’t change anything apart from installing the dual extruder and flashing the firmware. Any ideas?

Thanks!

Check your set screws on the motor shaft and the belt tension. Plus you might want to add a heat sink to the driver chip with that extra load it has now(dual head).

Yeah I was thinking this morning maybe with the extra weight the belt tension would need to be a little higher. I will check set screws as well.

As far as your heat sink suggestion, I’m looking in to it and it seems like people have a lot of opinions on how this should be done. Have you tried it? I was looking here: http://forum.seemecnc.com/viewtopic.php?t=6910 and am thinking about getting some taller standoffs for the board and putting some heat sinks on the back, and maybe one for the ATMEL too since that should help with keep the entire board cool.

Anyway thanks for the tips!