Experimentation: Print Pausing, Part Insertion, Techniques.

[RobH2]

I'm starting a thread about something I'm interested in and have not experimented with much. That's stopping the print and inserting things, wires, nuts, reinforcements, etc., and then resuming the print to encapsulate them. Member "beerdart" mentioned that Cura has a plugin that handles that. I'm going to move his post over here and open the floor. It's the first thread above this one.

[beerdart]

Cura comes with a "Plug-In" called pause at height where you tell it when to pause and where to park the head,

[beerdart]

I have yet to play with it but may try on this part to change filament color for the raised letters. Just waiting on some red filament to show up Im going with a black ring and red letters.

[RobH2]

I look forward to seeing it. I've been thinking about going "dual" head. Until then, I might try doing what you are doing a bit. Post some photos after you get it going.

I want to make a part, insert some wires and reinforcement, and then seal it in. It's not brain surgery I don't think. I need to find the Cura plugin you are talking about. It might turn out to be pretty simple. I worry about the already laid down layers cooling off too much and then the new layers not sticking. Is that an issue do you think?

[RobH2]

I'm assuming you have a one head printer and you are going to stop it, change to red, let it do the letters? Is that the plan?

It looks like the highest part of the letters it the height of the main body. But, the base of the letters is some number of layers lower. Are you going to have the head just go into the letter area and print? If the head moves too far the wrong way it will hit the higher print and mess things up. Maybe it's a shadow in the photo and the letters bases are the height of the rest of the ring.

I'm curious about this...

[beerdart]

Yes its a single head my plan is to stop for the change after the first or second layer of the letters above the part.

[beerdart]

http://wiki.ultimaker.com/CuraPlugin:_Pauseatz

https://github.com/daid/Cura/tree/SteamEngine/plugins

[RobH2]

Excellent. Thanks. I'm glad to see things like "plugins" being offered. I didn't realize those options were available. The best part about all of this is you can learn something new every day.

Edit: There is still one issue I'd like to experiment with and solve. This warning was attached to the Cura plugin: "Always make sure the object is not sticking out above the plane print head moves in, otherwise it may cause damage to your product. ."

I'd like to find a way to stop the print, insert something that does stick up, and then encapsulate it. I wonder of GCode is robust enough to allow you to stay away from an area or to build around an area if you have very, very good measurements? I guess that would not work unless the object that protruded had a lot of curvature, like a marble. Otherwise, the tip of the hotend would bump the object. You'd always have to stay as far away as the physical extrusion tip diameter, at least till you got high enough to bridge and fill over. Then you have a potential non-sticking problem and other issues arise. This is going to be a tricky task for a 3d printer in it's current configuration to perform. I haven't dived in and written much GCode yet. I've inserted a command here and there but have not created any truly custom code to do a lengthy task.

So for now, for RepRappers anyway, pausing is good if you bury the insert and or just want to swap colors.

[3dkarma]

If you plan on inserting something into your print, you'll need to build a cavity for it into your design. You'll only be able to insert something once the print head has reached a point at least as high as the highest point of the inserted part, once it's been inserted. You won't be able to insert something that ends up sitting higher than the layer you're currently printing at or the chances are very high your print head will collide with it.

[RobH2]

You are exactly correct and that's what I see in the current state of things as being a limitation. It would be really nice if you didn't have to bury it and make sure it was at or lower then the next level. I don't doubt someone, somewhere is working on a workaround. That's just one of the features of really high end commercial printers, the ability to insert objects without such limitations. I saw a video of one printer for a project I did where we were animating 3d printing and sintering technologies for Oakridge National Laboratories. They were able to insert all kinds of things into a print and not bury them. I hope that functionality can trickle down to we users on the lower end of that totem pole.