Two Extruders with arbitrary offsets = MASSIVE DITTO Prints!


A few months ago, I sent you an idea for two single extruders on the same X rail that could have their x offsets adjusted (from each other) arbitrarily so objects could be Ditto printed close to 50% of the bed width and not be limited in size by the distance of the two nozzles as they are on a typical dual extruder. I had just built Phat Freddy (custom gMax) as a single extruder, upgraded him to a dual and did not want to strip him back down to two singles to do this. But I had been thinking about this for a long time since I do a lot of ditto printing and continue to think about the best design for ease of use that will produce quality Dittos.

To the best of my knowledge, nobody has created a printer that has ditto printing capabilities with arbitrary offsets and I thought the gMax would be perfect for it due to it's generous build volumes. It's a whole lot better to ditto on a 16" wide print area than a cocktail napkin sized print bed.

I am glad to see that this was taken into consideration. The image in the gallery is very exciting. I am hoping the Ditto printing features I reworked into the firmware provide some inspiration for this to move forward.

I think if ditto printing was exposed to more people, they would see the true power in it. It's definitely not a novelty and if it can be industrial sized (arbitrary offsets) it would be a total game changer. Even now, there are many duplicate parts I need to print. Print times are cut in half. Now supersize the objects and it makes the gMax a ridiculous powerhouse of a printer (it already is but you get my point). I am not sure how Reddit would do the math, but you guys would crush even more than you just did.

If this is indeed the direction you're going, a suggestion I would like to make is to have the main belt connected to just the left extruder and have the right extruder connected to the left via a quick release turnbuckle/adjustable bolt(s) to adjust the offsets. This would accomplish three things.

1) It would make taking the second carriage on and off a breeze as there are no belts to undo or tighten. The carriages ride on the rails so the bolt would basically be pushing and pulling the right carriage with

2) It would remove any lag or tension difference between the two belts. My first thought was you would have to have the tension very similar if not the same on the two belts as a change in direction at higher heights may cause a shifting issue or give the appearance of one. A stiffer/more rigid connector like a threaded bolt between the two would keep them mechanically in synch.

3) You never have to mess with the left extruders belt so if you decided to remove the second (extruder) you wouldn't have to go through belt tensioning or calibration again so if you have your printer dialed in and don't want to mess with the belt, you wouldn't have to.

Again, I'm really stoked to see that image. Can't wait to see what's next.