12" I3V Build

[Dustin B]

Two votes for ABL and only Colin and one other guy I've seen in my browsing on this forum against it. Might end up happening sooner than later then :P

Any thoughts on passive heat sinks on the axis steppers? They are pretty cheap online so can't see how they'd hurt.

Might start with that on the extruder too and go active if I notice them getting too hot.

[Chadd]

Are you talking about heat sinks for the motors or stepper drivers? My kit came with small heat sinks for the drivers, my motors have never gotten hot enough that I would consider cooling for them.

Two votes for ABL and only Colin and one other guy I've seen in my browsing on this forum against it. Might end up happening sooner than later then :P

Any thoughts on passive heat sinks on the axis steppers? They are pretty cheap online so can't see how they'd hurt.

Might start with that on the extruder too and go active if I notice them getting too hot.

[printbus]

Thanks for posting a pic of the relay. A few have mentioned the built-in relay, but I believe you're the first to provide a picture of it. This reveals the heat bed is using the same 30-amp G8QN Omron mechanical relay that is used on the standalone relay board.

To go the PID route, you'd first want to remove the two small black wires from the heat bed. You might be able to reuse the wires to control the SSR, but the SSR will require you to keep the polarity straight between the electronics board and the SSR. The mechanical relay didn't care.

After that, removing the relay depends on how comfortable you are in attempting to remove it. The two pins that solder to the wide traces would be a problem for some. I'd probably just jumper across those two pins with some heavy wire, leaving the relay there in case you roll back to using it. There'd be two options to jumpering across the pins. You could move the heavy gauge wire from the wide trace just going to the relay to the relay pin connecting to the other wide trace, but the solder pad there is smaller. The other option would be to scrape away the soldermask on the two wide traces where they are the closest and build a solder bridge to short the two traces together.

[printbus]

I'd argue that something is wrong if tightening the wheel mounting bolt changes how freely the wheel spins. The only way it should make a difference is if the nut is backed off enough that the inner race isn't held tight and it's spinning on the bolt. IMO that's way too loose; I prefer for the bolt to tighten solidly on the inner races. That said, there's a few things to note.

These are greased bearings, which do require some run time to loosen up.

The OD of the inner races are pretty small, and don't clear the rotating part of the bearing by much. Make sure the nut, bolt head, spacer, or anything else mating with the inner race ONLY touches the inner race. You don't want anything rubbing on the rotating part of the bearing beyond the inner race. Add some shims if there's a doubt.

Did your wheels come preassembed? It might be worth taking one apart to make sure there's a proper shim washer installed between the two bearings. The problem here is that the wheels are wider than the two bearings are, and the shim washer is required to make up the difference between the two bearings. If there's no shim washer installed, the bearings aren't fully seated in the wheels, or the shim washer isn't thick enough, tightening the wheel mounting bolt puts axial pressure on the inner and outer parts of the bearing, which will cause binding in the bearings. Note that openBuildsPartsStore has precision washers for this - http://openbuildspartstore.com/precision-shim-10x5x1mm/