nanoDLP

rob

Member

Registered: 2017-09-28

Posts: 54

Help with bottom-up setup and few concepts clarification

Dear all,

I've been visiting the forum for a few months now and I finally registered to ask for some help and hopefully give back to the community.
I'm working on porting an existing custom bottom-up printer (projector below the VAT) to NanoDLP.
I would like to check if I got some basic concepts right.

My first step was change proprietary electronics to a RAMPS-compatible RUMBA board. I installed patched Marlin firmware.
Muve patched firmware is stuck at version 1.0. I saw there is also a patched version 1.0.2 by user WheresWaldo with less changes from original firmware.
1) What are necessary modifications to original Marlin to work with NanoDLP? I guess the main one is "Z_move_comp" message after G0/G1 Z axis move. Are there any other necessary or suggested?
2) Is there any chance to contribute this changes back to original Marlin as a configuration option? This way they might be inherited by newer versions (1.1.5 is out and many functions has been added/improved).

3) Was NanoDLP originally developed for top-down or bottom-up setup? I ask it to understand in which case modification have to be taken into account (Z axis and homing direction, etc).
4) What should be correct Z axis configuration for a bottom-up setup. Current config is Z+ direction downwards, Z- upwards, with a Z-min endstop placed at the top. It means moving Z in positive direction (i.e. G1 Z100) lowers the lift downward toward the VAT.
Not sure if this might generate confusion (seems counter-intuitive), so I would ask if is there any standard about Z axis definition. I know you can have same results flipping all settings, but I would like to follow the standard (if any).

Thanks in advance to all contributions. Hope I didn't mix too many questions in one post.

Shahin

Administrator

Registered: 2016-02-17

Posts: 3,546

Re: Help with bottom-up setup and few concepts clarification

1) Z_move_comp is not necessary you can handle movement synchronization using delay keyword too so you do not need patched firmware and any firmware will be usable. But majority of users prefer to have patched firmware.
2) You should ask on marlin repo, see if they accept it back.
3) bottom up
4) For RAMPS it depends mostly on firmware as nanodlp supports both directions.