Flying extruder with 4th axis

ander

Hi there!
I made some calculations, and having a 300mm teflon tube and 400mm diameter printing area, when the effector goes to the corner the effector needs to go down 75 mm aproximately, maybe a little bit less taking in mind that the motor also turns. i think that once having the firmware i will need to do many tests and play with those numbers

dc42

Are you sure that screw drive will be able to move the extruder fast enough? The screw pitch looks very fine in the photo.

ander

I´m not sure at all....we need to test for that, but i didnt wanted to put a belt because it will move down when switching off the printer bending the teflon tube. i think test is needed to see how works and then modify if is needed

timcurtis67

@dc42 said in Flying extruder with 4th axis:

Are you sure that screw drive will be able to move the extruder fast enough? The screw pitch looks very fine in the photo.

I agree, it looks really fine pitched. I would be using a 4 lead screw that turns 8mm per revolution. I use them on my big printer and can move my heavy table really fast.

I like the design though. Great job on it.

ander

Thanks mate!! I also thought on puting this 4 lead screw but keep in mind that there is 1m long...i had hard time looking for the ones that make 8mm per revolution being 1m long. i did some tests with this configuration and moves really well but you have to push hard in order to gain some speed. another fast option would be to put belts with some counterweight in the other end so there would be no problem when switching off AND it would be more quiet.

ander

Here goes another picture of the whole system

ander

By the way the pitch i´m using is 1.25mm. It is a regular M8 thread

Alexander Mundy

Details of the firmware settings for this? Sorry if I didn't understand. I would like to do something similar on my delta but for a camera that follows the Z height of the print but offset by a set amount.

Danal

@alexander-mundy said in Flying extruder with 4th axis:

Details of the firmware settings for this? Sorry if I didn't understand. I would like to do something similar on my delta but for a camera that follows the Z height of the print but offset by a set amount.

Would you be interested in an $10 for the parts (not including stepper or servo) external box that "polls" the printer and does this? It could drive a stepper or a servo (angle, not movement). I've been thinking about creating one, and am curious if others would find it interesting.

ander

@alexander-mundy This system was also built thinking on putting a camera to the moveable arm...i designed some holes to attach a camera in a future

timcurtis67

@ander said in Flying extruder with 4th axis:

By the way the pitch i´m using is 1.25mm. It is a regular M8 thread

You can always use a lower microstep setting (1/4 or 1/2) or just use full steps but you will have much more stepper motor noise that way. It will move faster though.

ander

I just found and ordered 4 lead screw of 1m long, is going to move so much faster, and this way i don´t have to change anything to the original setup for now....after uploading the firmware we will see if aditional features are needed when testing like some system to help the motor not to be super bowncy

ander

Hi there!!
I just received the lead screw, tomorrow i will change it so the 4th axis can move so much faster.

@dc42 , did you have any chance of working on the firmware?
i had to cut the 1.2m teflon tube that was going from the motor to the hotend to make the modification and now the printer is not working ever since.

dc42

@ander said in Flying extruder with 4th axis:

Hi there!!
I just received the lead screw, tomorrow i will change it so the 4th axis can move so much faster.

@dc42 , did you have any chance of working on the firmware?
i had to cut the 1.2m teflon tube that was going from the motor to the hotend to make the modification and now the printer is not working ever since.

I'm sorry, I won't have time to look at this until the 2.02 release is finished.

ander

Hi there!!
Did you have any chance to look at the 4th axis firmware? My delta is stopped since then

dc42

Yes, I have a build of RRF that supports up to 6 axes on a delta. Still some testing to do, but maybe you can help me with that?

ander

Hi There!
Of course i can help, my printer is ready for testing, tell me what to do and i will tell the results.

dc42

Please follow the instructions at https://duet3d.dozuki.com/Wiki/ConfiguringRepRapFirmwareDeltaPrinter?revisionid=HEAD#Section_Adding_additional_towers_to_carry_flying_extruders and use the binary at https://www.dropbox.com/s/fyvibzm0zl92hiy/Duet2CombinedFirmware.bin?dl=0. Caution: this is mostly untested! I suggest you test it at low speeds and reduced motor currents, and that you do not mount the extruder on the 4th carriage yet.

Monster Delta

which motor output would i use on the duet wifi or would i have to use a duex 5

dc42

Use M584 to create a U axis using any available motor output.

EDIT: I've just added some more to that new section on the page I linked to earlier.