Tiny update to purge bucket mod macros.

[edwardyeeks]

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Which mods/configurations/profiles are added by this PR?

Decontaminator purge bucket mod.

How was it tested?

No comment.

Any background context you want to provide?

Simply updating the macro. Some variables for brush and bucket dimensions were initially hidden away under the 'advanced' section, but it makes more sense to have them easily accessible along with the other variables and parameters. Minor readme update along the way. Did a previous PR which had problems due to unresolved conflicts in my own fork, so I closed that one and am simply resubmitting this. Pardon the crazy number of commit counts; I'm puzzled by it and am not sure what happened.

Screenshots (if appropriate)

None.

Further notes

None.

[edwardyeeks]

Looks like I must have fudged it up when I merged my feature branch into master at some point in the past. 🤦‍♀️ Let me know if this causes any issues.

Edward

[KiloQubit]

LGTM

Modification of existing mod. Checked:

• top level README already updated
• directory names have no spaces
• no stls modified
• configuration contains no keys or other secrets

[endurance1968]

Hi I think the left/right position calculation misses the half if the left bucket it should look like
G1 X{bucket_start + (bucket_left_width / 2) + (bucket_pos * (bucket_left_width / 2)) + (bucket_pos * bucket_gap) + (bucket_pos * (bucket_right_width / 2))}
otherwise it purges the filament onto the brush.

Further more a short retraction to release some pressure in the nozzle would make sense like
G1 E{purge_len} F{purge_spd}
G1 E-2 F{purge_spd} ;retract 2mm filament

to avoid that filament flows out of the nozzle immediately after cleaning and rehoming is again srewed up.

[edwardyeeks]

@endurance1968 this has been fixed as well as the retract feature added in the latest PR for the purge bucket here #218. It's still waiting to be merged into the main repo.

Edward